Programs & Examples On #Segments

Get Path from another app (WhatsApp)

protected void onCreate(Bundle savedInstanceState) { /* * Your OnCreate */ Intent intent = getIntent(); String action = intent.getAction(); String type = intent.getType();

//VIEW"
if (Intent.ACTION_VIEW.equals(action) && type != null) {viewhekper(intent);//Handle text being sent}

The response content cannot be parsed because the Internet Explorer engine is not available, or

It is sure because the Invoke-WebRequest command has a dependency on the Internet Explorer assemblies and are invoking it to parse the result as per default behaviour. As Matt suggest, you can simply launch IE and make your selection in the settings prompt which is popping up at first launch. And the error you experience will disappear.

But this is only possible if you run your powershell scripts as the same windows user as whom you launched the IE with. The IE settings are stored under your current windows profile. So if you, like me run your task in a scheduler on a server as the SYSTEM user, this will not work.

So here you will have to change your scripts and add the -UseBasicParsing argument, as ijn this example: $WebResponse = Invoke-WebRequest -Uri $url -TimeoutSec 1800 -ErrorAction:Stop -Method:Post -Headers $headers -UseBasicParsing

How to get current route

An easier way if you can't access router.url (for instance if you used skipLocationChange) you can use the following :

constructor(private readonly location: Location) {}

ngOnInit(): void {
  console.log(this.location.path());
}

How to customize the configuration file of the official PostgreSQL Docker image?

The postgres:9.4 image you've inherited from declares a volume at /var/lib/postgresql/data. This essentially means you can't copy any files to that path in your image; the changes will be discarded.

You have a few choices:

  • You could just add your own configuration files as a volume at run-time with docker run -v postgresql.conf:/var/lib/postgresql/data/postgresql.conf .... However, I'm not sure exactly how that will interact with the existing volume.

  • You could copy the file over when the container is started. To do that, copy your file into the build at a location which isn't underneath the volume then call a script from the entrypoint or cmd which will copy the file to correct location and start postgres.

  • Clone the project behind the Postgres official image and edit the Dockerfile to add your own config file in before the VOLUME is declared (anything added before the VOLUME instruction is automatically copied in at run-time).

  • Pass all config changes in command option in docker-compose file

like:

services:
  postgres:
    ...  
    command:
      - "postgres"
      - "-c"
      - "max_connections=1000"
      - "-c"
      - "shared_buffers=3GB"
      - "-c"
      ...

How to SSH into Docker?

These files will successfully open sshd and run service so you can ssh in locally. (you are using cyberduck aren't you?)

Dockerfile

FROM swiftdocker/swift
MAINTAINER Nobody

RUN apt-get update && apt-get -y install openssh-server supervisor
RUN mkdir /var/run/sshd
RUN echo 'root:password' | chpasswd
RUN sed -i 's/PermitRootLogin without-password/PermitRootLogin yes/' /etc/ssh/sshd_config

# SSH login fix. Otherwise user is kicked off after login
RUN sed 's@session\s*required\s*pam_loginuid.so@session optional pam_loginuid.so@g' -i /etc/pam.d/sshd

ENV NOTVISIBLE "in users profile"
RUN echo "export VISIBLE=now" >> /etc/profile

COPY supervisord.conf /etc/supervisor/conf.d/supervisord.conf

EXPOSE 22
CMD ["/usr/bin/supervisord"]

supervisord.conf

[supervisord]
nodaemon=true

[program:sshd]
command=/usr/sbin/sshd -D

to build / run start daemon / jump into shell.

docker build -t swift3-ssh .  
docker run -p 2222:22 -i -t swift3-ssh
docker ps # find container id
docker exec -i -t <containerid> /bin/bash

enter image description here

resize2fs: Bad magic number in super-block while trying to open

After reading about LVM and being familiar with PV -> VG -> LV, this works for me :

0) #df -h

Filesystem               Size  Used Avail Use% Mounted on
devtmpfs                 1.9G     0  1.9G   0% /dev
tmpfs                    1.9G     0  1.9G   0% /dev/shm
tmpfs                    1.9G  824K  1.9G   1% /run
tmpfs                    1.9G     0  1.9G   0% /sys/fs/cgroup
/dev/mapper/fedora-root   15G  2.1G   13G  14% /
tmpfs                    1.9G     0  1.9G   0% /tmp
/dev/md126p1             976M  119M  790M  14% /boot
tmpfs                    388M     0  388M   0% /run/user/0

1) # vgs

  VG     #PV #LV #SN Attr   VSize   VFree   
  fedora   1   2   0 wz--n- 231.88g 212.96g

2) # vgdisplay

  --- Volume group ---
  VG Name               fedora
  System ID
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  3
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               2
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               231.88 GiB
  PE Size               4.00 MiB
  Total PE              59361
  Alloc PE / Size       4844 / 18.92 GiB
  Free  PE / Size       54517 / 212.96 GiB
  VG UUID               9htamV-DveQ-Jiht-Yfth-OZp7-XUDC-tWh5Lv

3) # lvextend -l +100%FREE /dev/mapper/fedora-root

  Size of logical volume fedora/root changed from 15.00 GiB (3840 extents) to 227.96 GiB (58357 extents).
  Logical volume fedora/root successfully resized.

4) #lvdisplay

5) #fd -h

6) # xfs_growfs /dev/mapper/fedora-root

meta-data=/dev/mapper/fedora-root isize=512    agcount=4, agsize=983040 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=1 spinodes=0 rmapbt=0
         =                       reflink=0
data     =                       bsize=4096   blocks=3932160, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal               bsize=4096   blocks=2560, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 3932160 to 59757568

7) #df -h

Filesystem               Size  Used Avail Use% Mounted on
devtmpfs                 1.9G     0  1.9G   0% /dev
tmpfs                    1.9G     0  1.9G   0% /dev/shm
tmpfs                    1.9G  828K  1.9G   1% /run
tmpfs                    1.9G     0  1.9G   0% /sys/fs/cgroup
/dev/mapper/fedora-root  228G  2.3G  226G   2% /
tmpfs                    1.9G     0  1.9G   0% /tmp
/dev/md126p1             976M  119M  790M  14% /boot
tmpfs                    388M     0  388M   0% /run/user/0

Best Regards,

Problems using Maven and SSL behind proxy

A quick solution is add this code in your pom.xml:

<repositories>
    <repository>
        <id>central</id>
        <name>Maven Plugin Repository</name>
        <url>http://repo1.maven.org/maven2</url>
        <layout>default</layout>
        <snapshots>
            <enabled>false</enabled>
        </snapshots>
        <releases>
            <updatePolicy>never</updatePolicy>
        </releases>
    </repository>
</repositories>

Where never is for avoid the search a certified.

upstream sent too big header while reading response header from upstream

This is still the highest SO-question on Google when searching for this error, so let's bump it.

When getting this error and not wanting to deep-dive into the NGINX settings immediately, you might want to check your outputs to the debug console. In my case I was outputting loads of text to the FirePHP / Chromelogger console, and since this is all sent as a header, it was causing the overflow.

It might not be needed to change the webserver settings if this error is caused by just sending insane amounts of log messages.

How to add label in chart.js for pie chart

It is not necessary to use another library like newChart or use other people's pull requests to pull this off. All you have to do is define an options object and add the label wherever and however you want it in the tooltip.

var optionsPie = {
    tooltipTemplate: "<%= label %> - <%= value %>"
}

If you want the tooltip to be always shown you can make some other edits to the options:

 var optionsPie = {
        tooltipEvents: [],
        showTooltips: true,
        onAnimationComplete: function() {
            this.showTooltip(this.segments, true);
        },
        tooltipTemplate: "<%= label %> - <%= value %>"
    }

In your data items, you have to add the desired label property and value and that's all.

data = [
    {
        value: 480000,
        color:"#F7464A",
        highlight: "#FF5A5E",
        label: "Tobacco"
    }
];

Now, all you have to do is pass the options object after the data to the new Pie like this: new Chart(ctx).Pie(data,optionsPie) and you are done.

This probably works best for pies which are not very small in size.

Pie chart with labels

Drawing Circle with OpenGL

Here is a code to draw a fill elipse, you can use the same method but replacing de xcenter and y center with radius

void drawFilledelipse(GLfloat x, GLfloat y, GLfloat xcenter,GLfloat ycenter) {
    int i;
    int triangleAmount = 20; //# of triangles used to draw circle

    //GLfloat radius = 0.8f; //radius
    GLfloat twicePi = 2.0f * PI;

    glBegin(GL_TRIANGLE_FAN);
    glVertex2f(x, y); // center of circle
    for (i = 0; i <= triangleAmount; i++) {
        glVertex2f(
            x + ((xcenter+1)* cos(i * twicePi / triangleAmount)),
            y + ((ycenter-1)* sin(i * twicePi / triangleAmount))
        );
    }
    glEnd();
}

how to get the base url in javascript

Let's say you have your global scripts file and you don't want to define that URL repeatedly in other files. That's the point where BASE_URL kicks in.

In your global_script.js file, do this

<script>
 var BASE_URL = "http://localhost:8000";
</script>

Then you can use that variable anywhere else to call your URL. For example...

<script>
   fetch(`{{BASE_URL}}/task-create/`,{
         ..............
            
        }).then((response) => {
            .............
   })
</script>

Overlay normal curve to histogram in R

This is an implementation of aforementioned StanLe's anwer, also fixing the case where his answer would produce no curve when using densities.

This replaces the existing but hidden hist.default() function, to only add the normalcurve parameter (which defaults to TRUE).

The first three lines are to support roxygen2 for package building.

#' @noRd
#' @exportMethod hist.default
#' @export
hist.default <- function(x,
                         breaks = "Sturges",
                         freq = NULL,
                         include.lowest = TRUE,
                         normalcurve = TRUE,
                         right = TRUE,
                         density = NULL,
                         angle = 45,
                         col = NULL,
                         border = NULL,
                         main = paste("Histogram of", xname),
                         ylim = NULL,
                         xlab = xname,
                         ylab = NULL,
                         axes = TRUE,
                         plot = TRUE,
                         labels = FALSE,
                         warn.unused = TRUE,
                         ...)  {

  # https://stackoverflow.com/a/20078645/4575331
  xname <- paste(deparse(substitute(x), 500), collapse = "\n")

  suppressWarnings(
    h <- graphics::hist.default(
      x = x,
      breaks = breaks,
      freq = freq,
      include.lowest = include.lowest,
      right = right,
      density = density,
      angle = angle,
      col = col,
      border = border,
      main = main,
      ylim = ylim,
      xlab = xlab,
      ylab = ylab,
      axes = axes,
      plot = plot,
      labels = labels,
      warn.unused = warn.unused,
      ...
    )
  )

  if (normalcurve == TRUE & plot == TRUE) {
    x <- x[!is.na(x)]
    xfit <- seq(min(x), max(x), length = 40)
    yfit <- dnorm(xfit, mean = mean(x), sd = sd(x))
    if (isTRUE(freq) | (is.null(freq) & is.null(density))) {
      yfit <- yfit * diff(h$mids[1:2]) * length(x)
    }
    lines(xfit, yfit, col = "black", lwd = 2)
  }

  if (plot == TRUE) {
    invisible(h)
  } else {
    h
  }
}

Quick example:

hist(g)

enter image description here

For dates it's bit different. For reference:

#' @noRd
#' @exportMethod hist.Date
#' @export
hist.Date <- function(x,
                      breaks = "months",
                      format = "%b",
                      normalcurve = TRUE,
                      xlab = xname,
                      plot = TRUE,
                      freq = NULL,
                      density = NULL,
                      start.on.monday = TRUE,
                      right = TRUE,
                      ...)  {

  # https://stackoverflow.com/a/20078645/4575331
  xname <- paste(deparse(substitute(x), 500), collapse = "\n")

  suppressWarnings(
    h <- graphics:::hist.Date(
      x = x,
      breaks = breaks,
      format = format,
      freq = freq,
      density = density,
      start.on.monday = start.on.monday,
      right = right,
      xlab = xlab,
      plot = plot,
      ...
    )
  )

  if (normalcurve == TRUE & plot == TRUE) {
    x <- x[!is.na(x)]
    xfit <- seq(min(x), max(x), length = 40)
    yfit <- dnorm(xfit, mean = mean(x), sd = sd(x))
    if (isTRUE(freq) | (is.null(freq) & is.null(density))) {
      yfit <- as.double(yfit) * diff(h$mids[1:2]) * length(x)
    }
    lines(xfit, yfit, col = "black", lwd = 2)
  }

  if (plot == TRUE) {
    invisible(h)
  } else {
    h
  }
}

Redirect all to index.php using htaccess

To redirect everything that doesnt exist to index.php , you can also use the FallBackResource directive

FallbackResource /index.php

It works same as the ErrorDocument , when you request a non-existent path or file on the server, the directive silently forwords the request to index.php .

If you want to redirect everything (including existant files or folders ) to index.php , you can use something like the following :

RewriteEngine on

RewriteRule ^((?!index\.php).+)$ /index.php [L]

Note the pattern ^((?!index\.php).+)$ matches any uri except index.php we have excluded the destination path to prevent infinite looping error.

Where in memory are my variables stored in C?

A popular desktop architecture divides a process's virtual memory in several segments:

  • Text segment: contains the executable code. The instruction pointer takes values in this range.

  • Data segment: contains global variables (i.e. objects with static linkage). Subdivided in read-only data (such as string constants) and uninitialized data ("BSS").

  • Stack segment: contains the dynamic memory for the program, i.e. the free store ("heap") and the local stack frames for all the threads. Traditionally the C stack and C heap used to grow into the stack segment from opposite ends, but I believe that practice has been abandoned because it is too unsafe.

A C program typically puts objects with static storage duration into the data segment, dynamically allocated objects on the free store, and automatic objects on the call stack of the thread in which it lives.

On other platforms, such as old x86 real mode or on embedded devices, things can obviously be radically different.

What are the retransmission rules for TCP?

There's no fixed time for retransmission. Simple implementations estimate the RTT (round-trip-time) and if no ACK to send data has been received in 2x that time then they re-send.

They then double the wait-time and re-send once more if again there is no reply. Rinse. Repeat.

More sophisticated systems make better estimates of how long it should take for the ACK as well as guesses about exactly which data has been lost.

The bottom-line is that there is no hard-and-fast rule about exactly when to retransmit. It's up to the implementation. All retransmissions are triggered solely by the sender based on lack of response from the receiver.

TCP never drops data so no, there is no way to indicate a server should forget about some segment.

Adding an arbitrary line to a matplotlib plot in ipython notebook

Using vlines:

import numpy as np
np.random.seed(5)
x = arange(1, 101)
y = 20 + 3 * x + np.random.normal(0, 60, 100)
p =  plot(x, y, "o")
vlines(70,100,250)

The basic call signatures are:

vlines(x, ymin, ymax)
hlines(y, xmin, xmax)

How can I split a string into segments of n characters?

Here's a way to do it without regular expressions or explicit loops, although it's stretching the definition of a one liner a bit:

const input = 'abcdefghijlkm';

// Change `3` to the desired split length.
const output = input.split('').reduce((s, c) => {let l = s.length-1; (s[l] && s[l].length < 3) ? s[l] += c : s.push(c); return s;}, []);

console.log(output);  // output: [ 'abc', 'def', 'ghi', 'jlk', 'm' ]

It works by splitting the string into an array of individual characters, then using Array.reduce to iterate over each character. Normally reduce would return a single value, but in this case the single value happens to be an array, and as we pass over each character we append it to the last item in that array. Once the last item in the array reaches the target length, we append a new array item.

How to list processes attached to a shared memory segment in linux?

Use ipcs -a: it gives detailed information of all resources [semaphore, shared-memory etc]

Here is the image of the output:

image

How can I check if two segments intersect?

Calculate the intersection point of the lines laying on your segments (it means basically to solve a linear equation system), then check whether is it between the starting and ending points of your segments.

Downloading a picture via urllib and python

All the above codes, do not allow to preserve the original image name, which sometimes is required. This will help in saving the images to your local drive, preserving the original image name

    IMAGE = URL.rsplit('/',1)[1]
    urllib.urlretrieve(URL, IMAGE)

Try this for more details.

LINQ Joining in C# with multiple conditions

Your and should be a && in the where clause.

where epl.DepartAirportAfter >  sd.UTCDepartureTime 
and epl.ArriveAirportBy > sd.UTCArrivalTime

should be

where epl.DepartAirportAfter >  sd.UTCDepartureTime 
&& epl.ArriveAirportBy > sd.UTCArrivalTime

What resources are shared between threads?

Threads share the code and data segments and the heap, but they don't share the stack.

Spring schemaLocation fails when there is no internet connection

I had the same problem when I'm using spring-context version 4.0.6 and spring-security version 4.1.0.

When changing spring-security version to 4.0.4 (because 4.0.6 of spring-security not available) in my pom and security xml-->schemaLocation, it gets compiled without internet.

So that mean you can also solve this by:

  • changing spring-security to a older or same version than spring-context.

  • changing spring-context to a newer or same version than spring-security.

(any way spring-context to be newer or same version to spring-security)

maven compilation failure

i have an error like this, but after

1/

 mvn eclipse:clean
    mvn eclipse:eclipse -Dwtpversion=2.0

2/ run eclipse, and open the project

3/

mvn package

it's work

Understanding Linux /proc/id/maps

Each row in /proc/$PID/maps describes a region of contiguous virtual memory in a process or thread. Each row has the following fields:

address           perms offset  dev   inode   pathname
08048000-08056000 r-xp 00000000 03:0c 64593   /usr/sbin/gpm
  • address - This is the starting and ending address of the region in the process's address space
  • permissions - This describes how pages in the region can be accessed. There are four different permissions: read, write, execute, and shared. If read/write/execute are disabled, a - will appear instead of the r/w/x. If a region is not shared, it is private, so a p will appear instead of an s. If the process attempts to access memory in a way that is not permitted, a segmentation fault is generated. Permissions can be changed using the mprotect system call.
  • offset - If the region was mapped from a file (using mmap), this is the offset in the file where the mapping begins. If the memory was not mapped from a file, it's just 0.
  • device - If the region was mapped from a file, this is the major and minor device number (in hex) where the file lives.
  • inode - If the region was mapped from a file, this is the file number.
  • pathname - If the region was mapped from a file, this is the name of the file. This field is blank for anonymous mapped regions. There are also special regions with names like [heap], [stack], or [vdso]. [vdso] stands for virtual dynamic shared object. It's used by system calls to switch to kernel mode. Here's a good article about it: "What is linux-gate.so.1?"

You might notice a lot of anonymous regions. These are usually created by mmap but are not attached to any file. They are used for a lot of miscellaneous things like shared memory or buffers not allocated on the heap. For instance, I think the pthread library uses anonymous mapped regions as stacks for new threads.

How do you detect where two line segments intersect?

A C++ program to check if two given line segments intersect

#include <iostream>
using namespace std;

struct Point
{
    int x;
    int y;
};

// Given three colinear points p, q, r, the function checks if
// point q lies on line segment 'pr'
bool onSegment(Point p, Point q, Point r)
{
    if (q.x <= max(p.x, r.x) && q.x >= min(p.x, r.x) &&
        q.y <= max(p.y, r.y) && q.y >= min(p.y, r.y))
       return true;

    return false;
}

// To find orientation of ordered triplet (p, q, r).
// The function returns following values
// 0 --> p, q and r are colinear
// 1 --> Clockwise
// 2 --> Counterclockwise
int orientation(Point p, Point q, Point r)
{
    // See 10th slides from following link for derivation of the formula
    // http://www.dcs.gla.ac.uk/~pat/52233/slides/Geometry1x1.pdf
    int val = (q.y - p.y) * (r.x - q.x) -
              (q.x - p.x) * (r.y - q.y);

    if (val == 0) return 0;  // colinear

    return (val > 0)? 1: 2; // clock or counterclock wise
}

// The main function that returns true if line segment 'p1q1'
// and 'p2q2' intersect.
bool doIntersect(Point p1, Point q1, Point p2, Point q2)
{
    // Find the four orientations needed for general and
    // special cases
    int o1 = orientation(p1, q1, p2);
    int o2 = orientation(p1, q1, q2);
    int o3 = orientation(p2, q2, p1);
    int o4 = orientation(p2, q2, q1);

    // General case
    if (o1 != o2 && o3 != o4)
        return true;

    // Special Cases
    // p1, q1 and p2 are colinear and p2 lies on segment p1q1
    if (o1 == 0 && onSegment(p1, p2, q1)) return true;

    // p1, q1 and p2 are colinear and q2 lies on segment p1q1
    if (o2 == 0 && onSegment(p1, q2, q1)) return true;

    // p2, q2 and p1 are colinear and p1 lies on segment p2q2
    if (o3 == 0 && onSegment(p2, p1, q2)) return true;

     // p2, q2 and q1 are colinear and q1 lies on segment p2q2
    if (o4 == 0 && onSegment(p2, q1, q2)) return true;

    return false; // Doesn't fall in any of the above cases
}

// Driver program to test above functions
int main()
{
    struct Point p1 = {1, 1}, q1 = {10, 1};
    struct Point p2 = {1, 2}, q2 = {10, 2};

    doIntersect(p1, q1, p2, q2)? cout << "Yes\n": cout << "No\n";

    p1 = {10, 0}, q1 = {0, 10};
    p2 = {0, 0}, q2 = {10, 10};
    doIntersect(p1, q1, p2, q2)? cout << "Yes\n": cout << "No\n";

    p1 = {-5, -5}, q1 = {0, 0};
    p2 = {1, 1}, q2 = {10, 10};
    doIntersect(p1, q1, p2, q2)? cout << "Yes\n": cout << "No\n";

    return 0;
}

Checking length of dictionary object

var c = {'a':'A', 'b':'B', 'c':'C'};
var count = 0;
for (var i in c) {
   if (c.hasOwnProperty(i)) count++;
}

alert(count);

Get index of current item in a PowerShell loop

.NET has some handy utility methods for this sort of thing in System.Array:

PS> $a = 'a','b','c'
PS> [array]::IndexOf($a, 'b')
1
PS> [array]::IndexOf($a, 'c')
2

Good points on the above approach in the comments. Besides "just" finding an index of an item in an array, given the context of the problem, this is probably more suitable:

$letters = { 'A', 'B', 'C' }
$letters | % {$i=0} {"Value:$_ Index:$i"; $i++}

Foreach (%) can have a Begin sciptblock that executes once. We set an index variable there and then we can reference it in the process scripblock where it gets incremented before exiting the scriptblock.

Python: Total sum of a list of numbers with the for loop

x=[1,2,3,4,5]
sum=0
for s in range(0,len(x)):
   sum=sum+x[s]
print sum   

Write to .txt file?

Well, you need to first get a good book on C and understand the language.

FILE *fp;
fp = fopen("c:\\test.txt", "wb");
if(fp == null)
   return;
char x[10]="ABCDEFGHIJ";
fwrite(x, sizeof(x[0]), sizeof(x)/sizeof(x[0]), fp);
fclose(fp);

Opening XML page shows "This XML file does not appear to have any style information associated with it."

This XML file does not appear to have any style information associated with it. The document tree is shown below.

You will get this error in the client side when the client (the webbrowser) for some reason interprets the HTTP response content as text/xml instead of text/html and the parsed XML tree doesn't have any XML-stylesheet. In other words, the webbrowser incorrectly parsed the retrieved HTTP response content as XML instead of as HTML due to the wrong or missing HTTP response content type.

In case of JSF/Facelets files which have the default extension of .xhtml, that can in turn happen if the HTTP request hasn't invoked the FacesServlet and thus it wasn't able to parse the Facelets file and generate the desired HTML output based on the XHTML source code. Firefox is then merely guessing the HTTP response content type based on the .xhtml file extension which is in your Firefox configuration apparently by default interpreted as text/xml.

You need to make sure that the HTTP request URL, as you see in browser's address bar, matches the <url-pattern> of the FacesServlet as registered in webapp's web.xml, so that it will be invoked and be able to generate the desired HTML output based on the XHTML source code. If it's for example *.jsf, then you need to open the page by /some.jsf instead of /some.xhtml. Alternatively, you can also just change the <url-pattern> to *.xhtml. This way you never need to fiddle with virtual URLs.

See also:


Note thus that you don't actually need a XML stylesheet. This all was just misinterpretation by the webbrowser while trying to do its best to make something presentable out of the retrieved HTTP response content. It should actually have retrieved the properly generated HTML output, Firefox surely knows precisely how to deal with HTML content.

Getting the value of an attribute in XML

This is more of an xpath question, but like this, assuming the context is the parent element:

<xsl:value-of select="name/@attribute1" />

How to write a comment in a Razor view?

This comment syntax should work for you:

@* enter comments here *@

Call parent method from child class c#

To follow up on the comment by suhendri to Rory McCrossan answer. Here is an Action delegate example:

In child add:

public Action UpdateProgress;  // In place of event handler declaration
                               // declare an Action delegate
.
.
.
private LoadData() {
    this.UpdateProgress();    // call to Action delegate - MyMethod in
                              // parent
}

In parent add:

// The 3 lines in the parent becomes:
ChildClass child = new ChildClass();
child.UpdateProgress = this.MyMethod;  // assigns MyMethod to child delegate

How to avoid soft keyboard pushing up my layout?

To solve this simply add android:windowSoftInputMode="stateVisible|adjustPan to that activity in android manifest file. for example

<activity 
    android:name="com.comapny.applicationname.activityname"
    android:screenOrientation="portrait"
    android:windowSoftInputMode="stateVisible|adjustPan"/>

Extract month and year from a zoo::yearmon object

The lubridate package is amazing for this kind of thing:

> require(lubridate)
> month(date1)
[1] 3
> year(date1)
[1] 2012

How to implement Android Pull-to-Refresh

Very interesting Pull-to-Refresh by Yalantis. Gif for iOS, but you can check it :)

<com.yalantis.pulltorefresh.library.PullToRefreshView
android:id="@+id/pull_to_refresh"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
    android:id="@+id/list_view"
    android:divider="@null"
    android:dividerHeight="0dp"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

Check string for palindrome

Try this out :

import java.util.*;
    public class str {

        public static void main(String args[])
        {
          Scanner in=new Scanner(System.in);
          System.out.println("ENTER YOUR STRING: ");
          String a=in.nextLine();
          System.out.println("GIVEN STRING IS: "+a);
          StringBuffer str=new StringBuffer(a);
          StringBuffer str2=new StringBuffer(str.reverse());
          String s2=new String(str2);
          System.out.println("THE REVERSED STRING IS: "+str2);
            if(a.equals(s2))    
                System.out.println("ITS A PALINDROME");
            else
                System.out.println("ITS NOT A PALINDROME");
            }
    }

No module named _sqlite3

My _sqlite3.so is in /usr/lib/python2.5/lib-dynload/_sqlite3.so. Judging from your paths, you should have the file /usr/local/lib/python2.5/lib-dynload/_sqlite3.so.

Try the following:

find /usr/local -name _sqlite3.so

If the file isn't found, something may be wrong with your Python installation. If it is, make sure the path it's installed to is in the Python path. In the Python shell,

import sys
print sys.path

In my case, /usr/lib/python2.5/lib-dynload is in the list, so it's able to find /usr/lib/python2.5/lib-dynload/_sqlite3.so.

Restoring database from .mdf and .ldf files of SQL Server 2008

Yes, it is possible. The steps are:

  1. First Put the .mdf and .ldf file in C:\Program Files\Microsoft SQL Server\MSSQL.1\MSSQL\DATA\ folder

  2. Then go to sql software , Right-click “Databases” and click the “Attach” option to open the Attach Databases dialog box

  3. Click the “Add” button to open and Locate Database Files From C:\Program Files\Microsoft SQL Server\MSSQL.1\MSSQL\DATA\folder

  4. Click the "OK" button. SQL Server Management Studio loads the database from the .MDF file.

Passing environment-dependent variables in webpack

You can directly use the EnvironmentPlugin available in webpack to have access to any environment variable during the transpilation.

You just have to declare the plugin in your webpack.config.js file:

var webpack = require('webpack');

module.exports = {
    /* ... */
    plugins = [
        new webpack.EnvironmentPlugin(['NODE_ENV'])
    ]
};

Note that you must declare explicitly the name of the environment variables you want to use.

How do I conditionally apply CSS styles in AngularJS?

One more (in the future) way to conditionally apply style is by conditionally creating scoped style

<style scoped type="text/css" ng-if="...">

</style>

But nowadays only FireFox supports scoped styles.

Transpose a matrix in Python

If we wanted to return the same matrix we would write:

return [[ m[row][col] for col in range(0,width) ] for row in range(0,height) ]

What this does is it iterates over a matrix m by going through each row and returning each element in each column. So the order would be like:

[[1,2,3],
[4,5,6],
[7,8,9]]

Now for question 3, we instead want to go column by column, returning each element in each row. So the order would be like:

[[1,4,7],
[2,5,8],
[3,6,9]]

Therefore just switch the order in which we iterate:

return [[ m[row][col] for row in range(0,height) ] for col in range(0,width) ]

Difference between Grunt, NPM and Bower ( package.json vs bower.json )

Npm and Bower are both dependency management tools. But the main difference between both is npm is used for installing Node js modules but bower js is used for managing front end components like html, css, js etc.

A fact that makes this more confusing is that npm provides some packages which can be used in front-end development as well, like grunt and jshint.

These lines add more meaning

Bower, unlike npm, can have multiple files (e.g. .js, .css, .html, .png, .ttf) which are considered the main file(s). Bower semantically considers these main files, when packaged together, a component.

Edit: Grunt is quite different from Npm and Bower. Grunt is a javascript task runner tool. You can do a lot of things using grunt which you had to do manually otherwise. Highlighting some of the uses of Grunt:

  1. Zipping some files (e.g. zipup plugin)
  2. Linting on js files (jshint)
  3. Compiling less files (grunt-contrib-less)

There are grunt plugins for sass compilation, uglifying your javascript, copy files/folders, minifying javascript etc.

Please Note that grunt plugin is also an npm package.

Question-1

When I want to add a package (and check in the dependency into git), where does it belong - into package.json or into bower.json

It really depends where does this package belong to. If it is a node module(like grunt,request) then it will go in package.json otherwise into bower json.

Question-2

When should I ever install packages explicitly like that without adding them to the file that manages dependencies

It does not matter whether you are installing packages explicitly or mentioning the dependency in .json file. Suppose you are in the middle of working on a node project and you need another project, say request, then you have two options:

  • Edit the package.json file and add a dependency on 'request'
  • npm install

OR

  • Use commandline: npm install --save request

--save options adds the dependency to package.json file as well. If you don't specify --save option, it will only download the package but the json file will be unaffected.

You can do this either way, there will not be a substantial difference.

SELECT * FROM multiple tables. MySQL

In order to get rid of duplicates, you can group by drinks.id. But that way you'll get only one photo for each drinks.id (which photo you'll get depends on database internal implementation).

Though it is not documented, in case of MySQL, you'll get the photo with lowest id (in my experience I've never seen other behavior).

SELECT name, price, photo 
FROM drinks, drinks_photos 
WHERE drinks.id = drinks_id
GROUP BY drinks.id

How to serve up images in Angular2?

In angular only one page is requested from server, that is index.html. And index.html and assets folder are on same directory. while putting image in any component give src value like assets\image.png. This will work fine because browser will make request to server for that image and webpack will be able serve that image.

How do I force a favicon refresh?

Also make sure you put the full image URL not just its relative path:

http://www.example.com/images/favicon.ico

And not:

images/favicon.ico

Maximum call stack size exceeded error

Check the error details in the Chrome dev toolbar console, this will give you the functions in the call stack, and guide you towards the recursion that's causing the error.

How to get unique values in an array

If you don't need to worry so much about older browsers, this is exactly what Sets are designed for.

The Set object lets you store unique values of any type, whether primitive values or object references.

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set

const set1 = new Set([1, 2, 3, 4, 5, 1]);
// returns Set(5) {1, 2, 3, 4, 5}

How to hide a navigation bar from first ViewController in Swift?

In Swift 3, you can use isNavigationBarHidden Property also to show or hide navigation bar

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    // Hide the navigation bar for current view controller
    self.navigationController?.isNavigationBarHidden = true;
}

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    // Show the navigation bar on other view controllers
   self.navigationController?.isNavigationBarHidden = false;
}

Throwing exceptions in a PHP Try Catch block

function _modulename_getData($field, $table) {
  try {
    if (empty($field)) {
      throw new Exception("The field is undefined."); 
    }
    // rest of code here...
  }
  catch (Exception $e) {
    /*
        Here you can either echo the exception message like: 
        echo $e->getMessage(); 

        Or you can throw the Exception Object $e like:
        throw $e;
    */
  }
}

DateTime.ToString("MM/dd/yyyy HH:mm:ss.fff") resulted in something like "09/14/2013 07.20.31.371"

Convert Date To String

Use name Space

using System.Globalization;

Code

string date = DateTime.ParseExact(datetext.Text, "dd-MM-yyyy", CultureInfo.InstalledUICulture).ToString("yyyy-MM-dd");

How can I change the app display name build with Flutter?

For Android, change the app name from the Android folder. In the AndroidManifest.xml file, in folder android/app/src/main, let the android label refer to the name you prefer, for example,

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    <application
        `android:label="myappname"`
        // The rest of the code
    </application>
</manifest>

Git command to show which specific files are ignored by .gitignore

While generally correct your solution does not work in all circumstances. Assume a repo dir like this:

# ls **/*                                                                                                       
doc/index.html  README.txt  tmp/dir0/file0  tmp/file1  tmp/file2

doc:
index.html

tmp:
dir0  file1  file2

tmp/dir0:
file0

and a .gitignore like this:

# cat .gitignore
doc
tmp/*

This ignores the doc directory and all files below tmp. Git works as expected, but the given command for listing the ignored files does not. Lets have a look at what git has to say:

# git ls-files --others --ignored --exclude-standard                                                            
tmp/file1
tmp/file2

Notice that doc is missing from the listing. You can get it with:

# git ls-files --others --ignored --exclude-standard --directory                                                
doc/

Notice the additional --directory option.

From my knowledge there is no one command to list all ignored files at once. But I don't know why tmp/dir0 does not show up at all.

python NameError: name 'file' is not defined

file is not defined in Python3, which you are using apparently. The package you're instaling is not suitable for Python 3, instead, you should install Python 2.7 and try again.

See: http://docs.python.org/release/3.0/whatsnew/3.0.html#builtins

Using the slash character in Git branch name

Are you sure branch labs does not already exist (as in this thread)?

You can't have both a file, and a directory with the same name.

You're trying to get git to do basically this:

% cd .git/refs/heads
% ls -l
total 0
-rw-rw-r-- 1 jhe jhe 41 2009-11-14 23:51 labs
-rw-rw-r-- 1 jhe jhe 41 2009-11-14 23:51 master
% mkdir labs
mkdir: cannot create directory 'labs': File exists

You're getting the equivalent of the "cannot create directory" error.
When you have a branch with slashes in it, it gets stored as a directory hierarchy under .git/refs/heads.

Foreach with JSONArray and JSONObject

Apparently, org.json.simple.JSONArray implements a raw Iterator. This means that each element is considered to be an Object. You can try to cast:

for(Object o: arr){
    if ( o instanceof JSONObject ) {
        parse((JSONObject)o);
    }
}

This is how things were done back in Java 1.4 and earlier.

Quicksort with Python

Easy implementation from grokking algorithms

def quicksort(arr):
    if len(arr) < 2:
        return arr #base case
    else:
        pivot = arr[0]
        less = [i for i in arr[1:] if i <= pivot] 
        more = [i for i in arr[1:] if i > pivot]
        return quicksort(less) + [pivot] + quicksort(more)

Could not instantiate mail function. Why this error occurring

In Ubuntu (at least 12.04) it seems sendmail is not installed by default. You will have to install it using the command sudo apt-get install sendmail-bin

You may also need to configure the proper permissions for it as mentioned above.

How can I get the corresponding table header (th) from a table cell (td)?

Solution that handles colspan

I have a solution based on matching the left edge of the td to the left edge of the corresponding th. It should handle arbitrarily complex colspans.

I modified the test case to show that arbitrary colspan is handled correctly.

Live Demo

JS

$(function($) {
  "use strict";

  // Only part of the demo, the thFromTd call does the work
  $(document).on('mouseover mouseout', 'td', function(event) {
    var td = $(event.target).closest('td'),
        th = thFromTd(td);
    th.parent().find('.highlight').removeClass('highlight');
    if (event.type === 'mouseover')
      th.addClass('highlight');
  });

  // Returns jquery object
  function thFromTd(td) {
    var ofs = td.offset().left,
        table = td.closest('table'),
        thead = table.children('thead').eq(0),
        positions = cacheThPositions(thead),
        matches = positions.filter(function(eldata) {
          return eldata.left <= ofs;
        }),
        match = matches[matches.length-1],
        matchEl = $(match.el);
    return matchEl;
  }

  // Caches the positions of the headers,
  // so we don't do a lot of expensive `.offset()` calls.
  function cacheThPositions(thead) {
    var data = thead.data('cached-pos'),
        allth;
    if (data)
      return data;
    allth = thead.children('tr').children('th');
    data = allth.map(function() {
      var th = $(this);
      return {
        el: this,
        left: th.offset().left
      };
    }).toArray();
    thead.data('cached-pos', data);
    return data;
  }
});

CSS

.highlight {
  background-color: #EEE;
}

HTML

<table>
    <thead> 
        <tr>
            <th colspan="3">Not header!</th>
            <th id="name" colspan="3">Name</th>
            <th id="address">Address</th>
            <th id="address">Other</th>
        </tr>
    </thead> 
    <tbody>
        <tr>
            <td colspan="2">X</td>
            <td>1</td>
            <td>Bob</td>
            <td>J</td>
            <td>Public</td>
            <td>1 High Street</td>
            <td colspan="2">Postfix</td>
        </tr>
    </tbody>
</table>

Converting double to string

Use StringBuilder class, like so:

StringBuilder meme = new StringBuilder(" ");

// Convert and append your double variable
meme.append(String.valueOf(doubleVariable));

// Convert string builder to string
jTextField9.setText(meme.toString());

You will get you desired output.

How do I make the scrollbar on a div only visible when necessary?

try

<div id="boxscroll2" style="overflow: auto; position: relative;" tabindex="5001">

Get UserDetails object from Security Context in Spring MVC controller

You can use below code to find out principal (user email who logged in)

  org.opensaml.saml2.core.impl.NameIDImpl principal =  
  (NameIDImpl) SecurityContextHolder.getContext().getAuthentication().getPrincipal();

  String email = principal.getValue();

This code is written on top of SAML.

Reading PDF documents in .Net

PDFClown might help, but I would not recommend it for a big or heavy use application.

How to use random in BATCH script?

Let's say you want a number 1-5; you could use the following:

    :LOOP
    set NUM=%random:~-1,1%
    if %NUM% GTR 5 (
    goto LOOP )
    goto NEXT

Or you could use :~1,1 in place of :~-1,1. The :~-1,1 is not needed, but it greatly reduces the amount of time it takes to hit the right range. Let's say you want a number 1-50, we need to decide between 2 digits and 1 digit. Use:

    :LOOP
    set RAN1=%random:~-1,1%
    if %RAN1% GTR 5 (
    goto 1 )
    if %RAN1%==5 (
    goto LOOP )
    goto 2

    :1
    set NUM=%random:~-1,1%
    goto NEXT

    :2
    set NUM=%random:~-1,2%
    goto NEXT

You can add more to this algorithm to decide between large ranges, such as 1-1000.

How to get second-highest salary employees in a table

This query display all the details of the Employees with second highest salary

SELECT
    *
FROM
    Employees
WHERE
    salary IN (
        SELECT
            max(salary)
        FROM
            Employees
        WHERE
            salary NOT IN (
                SELECT
                    max(salary)
                FROM
                    Employees
            )
    );

How do I format a date as ISO 8601 in moment.js?

If you just want the date portion (e.g. 2017-06-27), and you want it to work regardless of time zone and also in Arabic, here is code I wrote:

function isoDate(date) {
    if (!date) {
        return null
    }
    date = moment(date).toDate()

    // don't call toISOString because it takes the time zone into
    // account which we don't want.  Also don't call .format() because it
    // returns Arabic instead of English

    var month = 1 + date.getMonth()
    if (month < 10) {
        month = '0' + month
    }
    var day = date.getDate()
    if (day < 10) {
        day = '0' + day
    }
    return date.getFullYear() + '-' + month + '-' + day
}

Android: remove left margin from actionbar's custom layout

It would be better to add a background item into the style of the app actionbar to consistent with the background color of the customized actionbar:

<item name="android:background">@color/actionbar_bgcolor</item>

After android 6.0, the actionbar even has a margin-right space and cannot be set. Add a right margin adjusting in the activity like this: (the view is the customized actionbar or a right button in it)

int rightMargin = Build.VERSION.SDK_INT>=Build.VERSION_CODES.M ? 0 : 8; // may the same with actionbar leftMargin in px
ViewGroup.MarginLayoutParams p = (ViewGroup.MarginLayoutParams) view.getLayoutParams();
p.setMargins(p.leftMargin, p.topMargin, rightMargin, p.bottomMargin);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1){
    p.setMarginEnd(rightMargin);
}
view.setLayoutParams(p);

The actionbar machenism is just supported after Android 3.0+ app. If we use a toolbar (of support lib v7) instead, we should layout it in each xml of each activity, and take care of the issue of overlapping with system status bar in the Android 5.0 or later device.

Why std::cout instead of simply cout?

It seems possible your class may have been using pre-standard C++. An easy way to tell, is to look at your old programs and check, do you see:

#include <iostream.h>

or

#include <iostream>

The former is pre-standard, and you'll be able to just say cout as opposed to std::cout without anything additional. You can get the same behavior in standard C++ by adding

using std::cout;

or

using namespace std;

Just one idea, anyway.

CentOS: Copy directory to another directory

cp -r /home/server/folder/test /home/server/

What does principal end of an association means in 1:1 relationship in Entity framework

In one-to-one relation one end must be principal and second end must be dependent. Principal end is the one which will be inserted first and which can exist without the dependent one. Dependent end is the one which must be inserted after the principal because it has foreign key to the principal.

In case of entity framework FK in dependent must also be its PK so in your case you should use:

public class Boo
{
    [Key, ForeignKey("Foo")]
    public string BooId{get;set;}
    public Foo Foo{get;set;}
}

Or fluent mapping

modelBuilder.Entity<Foo>()
            .HasOptional(f => f.Boo)
            .WithRequired(s => s.Foo);

Uploading Laravel Project onto Web Server

All of your Laravel files should be in one location. Laravel is exposing its public folder to server. That folder represents some kind of front-controller to whole application. Depending on you server configuration, you have to point your server path to that folder. As I can see there is www site on your picture. www is default root directory on Unix/Linux machines. It is best to take a look inside you server configuration and search for root directory location. As you can see, Laravel has already file called .htaccess, with some ready Apache configuration.

How do you do the "therefore" (?) symbol on a Mac or in Textmate?

From System Preferences, turn on the "Show Keyboard & Character Viewer in menu bar" setting.

Then, the "Character Viewer" menu will pop up a tool that will let you search for any unicode character (by name) and insert it ? you're all set.

this is error ORA-12154: TNS:could not resolve the connect identifier specified?

run the below command in command prompt

tnsping Datasource

This should give a response like below

C:>tnsping *******

TNS Ping Utility for *** Windows: Version *** - Production on *****

Copyright (c) 1997, 2014, Oracle. All rights reserved.

Used parameter files: c:\oracle*****

Used **** to resolve the alias Attempting to contact (description=(address_list=(address=(protocol=tcp)(host=)(port=)))(connect_data=(server=)(service_name=)(failover_mode=(type=)(method=)(retries=)(delay=))))** OK (**** msec)

Add the text 'Datasource=' in beginning and credentials at the end. the final string should be

Data Source=(description=(address_list=(address=(protocol=tcp)(host=)(port=)))(connect_data=(server=)(service_name=)(failover_mode=(type=)(method=)(retries=)(delay=))));User Id=;Password=;**

Use this as the connection string to connect to oracle db.

$.focus() not working

Found a solution elsewhere on the net...

$('#id').focus();

did not work.

$('#id').get(0).focus();

did work.

Accessing dict_keys element by index in Python3

Try this

keys = [next(iter(x.keys())) for x in test]
print(list(keys))

The result looks like this. ['foo', 'hello']

You can find more possible solutions here.

VBA: How to display an error message just like the standard error message which has a "Debug" button?

First the good news. This code does what you want (please note the "line numbers")

Sub a()
 10:    On Error GoTo ErrorHandler
 20:    DivisionByZero = 1 / 0
 30:    Exit Sub
 ErrorHandler:
 41: If Err.Number <> 0 Then
 42:    Msg = "Error # " & Str(Err.Number) & " was generated by " _
         & Err.Source & Chr(13) & "Error Line: " & Erl & Chr(13) & Err.Description
 43:    MsgBox Msg, , "Error", Err.HelpFile, Err.HelpContext
 44:    End If
 50:    Resume Next
 60: End Sub

When it runs, the expected MsgBox is shown:

alt text

And now the bad news:
Line numbers are a residue of old versions of Basic. The programming environment usually took charge of inserting and updating them. In VBA and other "modern" versions, this functionality is lost.

However, Here there are several alternatives for "automatically" add line numbers, saving you the tedious task of typing them ... but all of them seem more or less cumbersome ... or commercial.

HTH!

Why use the INCLUDE clause when creating an index?

There is a limit to the total size of all columns inlined into the index definition. That said though, I have never had to create index that wide. To me, the bigger advantage is the fact that you can cover more queries with one index that has included columns as they don't have to be defined in any particular order. Think about is as an index within the index. One example would be the StoreID (where StoreID is low selectivity meaning that each store is associated with a lot of customers) and then customer demographics data (LastName, FirstName, DOB): If you just inline those columns in this order (StoreID, LastName, FirstName, DOB), you can only efficiently search for customers for which you know StoreID and LastName.

On the other hand, defining the index on StoreID and including LastName, FirstName, DOB columns would let you in essence do two seeks- index predicate on StoreID and then seek predicate on any of the included columns. This would let you cover all possible search permutationsas as long as it starts with StoreID.

How can I send an HTTP POST request to a server from Excel using VBA?

Set objHTTP = CreateObject("MSXML2.ServerXMLHTTP")
URL = "http://www.somedomain.com"
objHTTP.Open "POST", URL, False
objHTTP.setRequestHeader "User-Agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)"
objHTTP.send("")

Alternatively, for greater control over the HTTP request you can use WinHttp.WinHttpRequest.5.1 in place of MSXML2.ServerXMLHTTP.

Correct way to select from two tables in SQL Server with no common field to join on

You can (should) use CROSS JOIN. Following query will be equivalent to yours:

SELECT 
   table1.columnA
 , table2.columnA
FROM table1 
CROSS JOIN table2
WHERE table1.columnA = 'Some value'

or you can even use INNER JOIN with some always true conditon:

FROM table1 
INNER JOIN table2 ON 1=1

git diff between cloned and original remote repository

Another reply to your questions (assuming you are on master and already did "git fetch origin" to make you repo aware about remote changes):

1) Commits on remote branch since when local branch was created:

git diff HEAD...origin/master

2) I assume by "working copy" you mean your local branch with some local commits that are not yet on remote. To see the differences of what you have on your local branch but that does not exist on remote branch run:

git diff origin/master...HEAD

3) See the answer by dbyrne.

Laravel migration table field's type change

2018 Solution, still other answers are valid but you dont need to use any dependency:

First you have to create a new migration:

php artisan make:migration change_appointment_time_column_type

Then in that migration file up(), try:

    Schema::table('appointments', function ($table) {
        $table->string('time')->change();
    });

If you donot change the size default will be varchar(191) but If you want to change size of the field:

    Schema::table('appointments', function ($table) {
        $table->string('time', 40)->change();
    });

Then migrate the file by:

php artisan migrate

more info from doc.

RegEx: How can I match all numbers greater than 49?

Next matches all greater or equal to 11100:

^([1-9][1-9][1-9]\d{2}\d*|[1-9][2-9]\d{3}\d*|[2-9]\d{4}\d*|\d{6}\d*)$

For greater or equal 50:

^([5-9]\d{1}\d*|\d{3}\d*)$

See pattern and modify to any number. Also it would be great to find some recursive forward/backward operators for large numbers.

Javascript date regex DD/MM/YYYY

For people who needs to validate years earlier than year 1900, following should do the trick. Actually this is same as the above answer given by [@OammieR][1] BUT with years including 1800 - 1899.

/^(((0[1-9]|[12]\d|3[01])\/(0[13578]|1[02])\/((19|[2-9]\d)\d{2}))|((0[1-9]|[12]\d|3[01])\/(0[13578]|1[02])\/((18|[2-9]\d)\d{2}))|((0[1-9]|[12]\d|30)\/(0[13456789]|1[012])\/((19|[2-9]\d)\d{2}))|((0[1-9]|[12]\d|30)\/(0[13456789]|1[012])\/((18|[2-9]\d)\d{2}))|((0[1-9]|1\d|2[0-8])\/02\/((19|[2-9]\d)\d{2}))|(29\/02\/((1[6-9]|[2-9]\d)(0[48]|[2468][048]|[13579][26])|((16|[2468][048]|[3579][26])00))))$/

Hope this helps someone who needs to validate years earlier than 1900, such as 01/01/1855, etc.

Thanks @OammieR for the initial idea.

Determining the last row in a single column

I realise this is quite an old thread but it's one of the first results when searching for this problem.

There's a simple solution to this which afaik has always been available... This is also the "recommended" way of doing the same task in VBA.

var lastCell = mySheet.getRange(mySheet.getLastRow(),1).getNextDataCell(
  SpreadsheetApp.Direction.UP
);

This will return the last full cell in the column you specify in getRange(row,column), remember to add 1 to this if you want to use the first empty row.

What does <a href="#" class="view"> mean?

I felt like replying as well, explaining the same thing as the others a bit differently. I am sure you know most of this, but it might help someone else.

<a href="#" class="view">

The

href="#"

part is a commonly used way to make sure the link doesn't lead anywhere on it's own. the #-attribute is used to create a link to some other section in the same document. For example clicking a link of this kind:

<a href="#news">Go to news</a>

will take you to wherever you have the

<a name="news"></a>

code. So if you specify # without any name like in your case, the link leads nowhere.

The

class="view"

part gives it an identifier that CSS or javascript can use. Inside the CSS-files (if you have any) you will find specific styling procedures on all the elements tagged with the "view"-class.

To find out where the URL is specified I would look in the javascript code. It is either written directly in the same document or included from another file.

Search your source code for something like:

<script type="text/javascript"> bla bla bla </script>

or

<script> bla bla bla </script>

and then search for any reference to your "view"-class. An included javascript file can look something like this:

<script type="text/javascript" src="include/javascript.js"></script>

In that case, open javascript.js under the "include" folder and search in that file. Most commonly the includes are placed between <head> and </head> or close to the </body>-tag.

A faster way to find the link is to search for the actual link it goes to. For example, if you are directed to http://www.google.com/search?q=html when you click it, search for "google.com" or something in all the files you have in your web project, just remember the included files.

In many text editors you can open all the files at once, and then search in them all for something.

transform object to array with lodash

_.toArray(obj);

Outputs as:

[
  {
    "name": "Ivan",
    "id": 12,
    "friends": [
      2,
      44,
      12
    ],
    "works": {
      "books": [],
      "films": []
    }
  },
  {
    "name": "John",
    "id": 22,
    "friends": [
      5,
      31,
      55
    ],
    "works": {
      "books": [],
      "films": []
    }
  }
]"

NoClassDefFoundError - Eclipse and Android

If you prefer to know which files the workaround is related to here's what I found. Simple change the .classpath file to

<?xml version="1.0" encoding="UTF-8"?>
<classpath>
    <classpathentry kind="src" path="src"/>
    <classpathentry kind="src" path="gen"/>
    <classpathentry exported="true" kind="con" path="com.android.ide.eclipse.adt.ANDROID_FRAMEWORK"/>
    <classpathentry exported="true" kind="con" path="com.android.ide.eclipse.adt.LIBRARIES"/>
    <classpathentry exported="true" kind="con" path="com.android.ide.eclipse.adt.DEPENDENCIES"/>
    <classpathentry kind="output" path="bin/classes"/>
</classpath>

Replace the .classpath file in all library projects and in main android project. The .classpath file is in the root folder of the eclipse project. Of cause don't forget to add your own classpath entries, should you have any (so compare with your current version of .classpath).

I believe this is the same result as going through the eclipse menus as componavt-user explained above (Eclipse / Configure Build Path / Order and Export).

How to error handle 1004 Error with WorksheetFunction.VLookup?

From my limited experience, this happens for two main reasons:

  1. The lookup_value (arg1) is not present in the table_array (arg2)

The simple solution here is to use an error handler ending with Resume Next

  1. The formats of arg1 and arg2 are not interpreted correctly

If your lookup_value is a variable you can enclose it with TRIM()

cellNum = wsFunc.VLookup(TRIM(currName), rngLook, 13, False)

How to solve 'Redirect has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header'?

In addition to what awd mentioned about getting the person responsible for the server to reconfigure (an impractical solution for local development) I use a change-origin chrome plugin like this:

Moesif Orign & CORS Changer

You can make your local dev server (ex: localhost:8080) to appear to be coming from 172.16.1.157:8002 or any other domain.

Working with TIFFs (import, export) in Python using numpy

Using cv2

import cv2
image = cv2.imread(tiff_file.tif)
cv2.imshow('tif image',image)

Loop through all the rows of a temp table and call a stored procedure for each row

Try returning the dataset from your stored procedure to your datatable in C# or VB.Net. Then the large amount of data in your datatable can be copied to your destination table using a Bulk Copy. I have used BulkCopy for loading large datatables with thousands of rows, into Sql tables with great success in terms of performance.

You may want to experiment with BulkCopy in your C# or VB.Net code.

Is it possible to override / remove background: none!important with jQuery?

div { background: none !important }
div { background: red; }

Is transparent.

div { background: none !important }
div { background: red !important; }

Is red.

An !important can override another !important.

If you can't edit the CSS file you can still add another one, or a style tag in the head tag.

How do I delete all the duplicate records in a MySQL table without temp tables

If you are not using any primary key, then execute following queries at one single stroke. By replacing values:

# table_name - Your Table Name
# column_name_of_duplicates - Name of column where duplicate entries are found

create table table_name_temp like table_name;
insert into table_name_temp select distinct(column_name_of_duplicates),value,type from table_name group by column_name_of_duplicates;
delete from table_name;
insert into table_name select * from table_name_temp;
drop table table_name_temp
  1. create temporary table and store distinct(non duplicate) values
  2. make empty original table
  3. insert values to original table from temp table
  4. delete temp table

It is always advisable to take backup of database before you play with it.

Phone number formatting an EditText in Android

If you're only interested in international numbers and you'd like to be able to show the flag of the country that matches the country code in the input, I wrote a small library for that:

https://github.com/tfcporciuncula/phonemoji

Here's how it looks:

library demo

Select count(*) from result query

This counts the rows of the inner query:

select count(*) from (
    select count(SID) 
    from Test 
    where Date = '2012-12-10' 
    group by SID
) t

However, in this case the effect of that is the same as this:

select count(distinct SID) from Test where Date = '2012-12-10'

jQuery ajax success error

I had the same problem;

textStatus = 'error'
errorThrown = (empty)
xhr.status = 0

That fits my problem exactly. It turns out that when I was loading the HTML-page from my own computer this problem existed, but when I loaded the HTML-page from my webserver it went alright. Then I tried to upload it to another domain, and again the same error occoured. Seems to be a cross-domain problem. (in my case at least)

I have tried calling it this way also:

var request = $.ajax({
url: "http://crossdomain.url.net/somefile.php", dataType: "text",
crossDomain: true,
xhrFields: {
withCredentials: true
}
});

but without success.

This post solved it for me: jQuery AJAX cross domain

Using HTML5/JavaScript to generate and save a file

Take a look at Doug Neiner's Downloadify which is a Flash based JavaScript interface to do this.

Downloadify is a tiny JavaScript + Flash library that enables the generation and saving of files on the fly, in the browser, without server interaction.

Simple state machine example in C#?

I've just contributed this:

https://code.google.com/p/ysharp/source/browse/#svn%2Ftrunk%2FStateMachinesPoC

Here's one of the examples demoing direct and indirect sending of commands, with states as IObserver(of signal), thus responders to a signal source, IObservable(of signal):

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Test
{
    using Machines;

    public static class WatchingTvSampleAdvanced
    {
        // Enum type for the transition triggers (instead of System.String) :
        public enum TvOperation { Plug, SwitchOn, SwitchOff, Unplug, Dispose }

        // The state machine class type is also used as the type for its possible states constants :
        public class Television : NamedState<Television, TvOperation, DateTime>
        {
            // Declare all the possible states constants :
            public static readonly Television Unplugged = new Television("(Unplugged TV)");
            public static readonly Television Off = new Television("(TV Off)");
            public static readonly Television On = new Television("(TV On)");
            public static readonly Television Disposed = new Television("(Disposed TV)");

            // For convenience, enter the default start state when the parameterless constructor executes :
            public Television() : this(Television.Unplugged) { }

            // To create a state machine instance, with a given start state :
            private Television(Television value) : this(null, value) { }

            // To create a possible state constant :
            private Television(string moniker) : this(moniker, null) { }

            private Television(string moniker, Television value)
            {
                if (moniker == null)
                {
                    // Build the state graph programmatically
                    // (instead of declaratively via custom attributes) :
                    Handler<Television, TvOperation, DateTime> stateChangeHandler = StateChange;
                    Build
                    (
                        new[]
                        {
                            new { From = Television.Unplugged, When = TvOperation.Plug, Goto = Television.Off, With = stateChangeHandler },
                            new { From = Television.Unplugged, When = TvOperation.Dispose, Goto = Television.Disposed, With = stateChangeHandler },
                            new { From = Television.Off, When = TvOperation.SwitchOn, Goto = Television.On, With = stateChangeHandler },
                            new { From = Television.Off, When = TvOperation.Unplug, Goto = Television.Unplugged, With = stateChangeHandler },
                            new { From = Television.Off, When = TvOperation.Dispose, Goto = Television.Disposed, With = stateChangeHandler },
                            new { From = Television.On, When = TvOperation.SwitchOff, Goto = Television.Off, With = stateChangeHandler },
                            new { From = Television.On, When = TvOperation.Unplug, Goto = Television.Unplugged, With = stateChangeHandler },
                            new { From = Television.On, When = TvOperation.Dispose, Goto = Television.Disposed, With = stateChangeHandler }
                        },
                        false
                    );
                }
                else
                    // Name the state constant :
                    Moniker = moniker;
                Start(value ?? this);
            }

            // Because the states' value domain is a reference type, disallow the null value for any start state value : 
            protected override void OnStart(Television value)
            {
                if (value == null)
                    throw new ArgumentNullException("value", "cannot be null");
            }

            // When reaching a final state, unsubscribe from all the signal source(s), if any :
            protected override void OnComplete(bool stateComplete)
            {
                // Holds during all transitions into a final state
                // (i.e., stateComplete implies IsFinal) :
                System.Diagnostics.Debug.Assert(!stateComplete || IsFinal);

                if (stateComplete)
                    UnsubscribeFromAll();
            }

            // Executed before and after every state transition :
            private void StateChange(IState<Television> state, ExecutionStep step, Television value, TvOperation info, DateTime args)
            {
                // Holds during all possible transitions defined in the state graph
                // (i.e., (step equals ExecutionStep.LeaveState) implies (not state.IsFinal))
                System.Diagnostics.Debug.Assert((step != ExecutionStep.LeaveState) || !state.IsFinal);

                // Holds in instance (i.e., non-static) transition handlers like this one :
                System.Diagnostics.Debug.Assert(this == state);

                switch (step)
                {
                    case ExecutionStep.LeaveState:
                        var timeStamp = ((args != default(DateTime)) ? String.Format("\t\t(@ {0})", args) : String.Empty);
                        Console.WriteLine();
                        // 'value' is the state value that we are transitioning TO :
                        Console.WriteLine("\tLeave :\t{0} -- {1} -> {2}{3}", this, info, value, timeStamp);
                        break;
                    case ExecutionStep.EnterState:
                        // 'value' is the state value that we have transitioned FROM :
                        Console.WriteLine("\tEnter :\t{0} -- {1} -> {2}", value, info, this);
                        break;
                    default:
                        break;
                }
            }

            public override string ToString() { return (IsConstant ? Moniker : Value.ToString()); }
        }

        public static void Run()
        {
            Console.Clear();

            // Create a signal source instance (here, a.k.a. "remote control") that implements
            // IObservable<TvOperation> and IObservable<KeyValuePair<TvOperation, DateTime>> :
            var remote = new SignalSource<TvOperation, DateTime>();

            // Create a television state machine instance (automatically set in a default start state),
            // and make it subscribe to a compatible signal source, such as the remote control, precisely :
            var tv = new Television().Using(remote);
            bool done;

            // Always holds, assuming the call to Using(...) didn't throw an exception (in case of subscription failure) :
            System.Diagnostics.Debug.Assert(tv != null, "There's a bug somewhere: this message should never be displayed!");

            // As commonly done, we can trigger a transition directly on the state machine :
            tv.MoveNext(TvOperation.Plug, DateTime.Now);

            // Alternatively, we can also trigger transitions by emitting from the signal source / remote control
            // that the state machine subscribed to / is an observer of :
            remote.Emit(TvOperation.SwitchOn, DateTime.Now);
            remote.Emit(TvOperation.SwitchOff);
            remote.Emit(TvOperation.SwitchOn);
            remote.Emit(TvOperation.SwitchOff, DateTime.Now);

            done =
                (
                    tv.
                        MoveNext(TvOperation.Unplug).
                        MoveNext(TvOperation.Dispose) // MoveNext(...) returns null iff tv.IsFinal == true
                    == null
                );

            remote.Emit(TvOperation.Unplug); // Ignored by the state machine thanks to the OnComplete(...) override above

            Console.WriteLine();
            Console.WriteLine("Is the TV's state '{0}' a final state? {1}", tv.Value, done);

            Console.WriteLine();
            Console.WriteLine("Press any key...");
            Console.ReadKey();
        }
    }
}

Note : this example is rather artificial and mostly meant to demo a number of orthogonal features. There should seldomly be a real need to implement the state value domain itself by a full blown class, using the CRTP ( see : http://en.wikipedia.org/wiki/Curiously_recurring_template_pattern ) like this.

Here's for a certainly simpler and likely much more common implementation use case (using a simple enum type as the states value domain), for the same state machine, and with the same test case :

https://code.google.com/p/ysharp/source/browse/trunk/StateMachinesPoC/WatchingTVSample.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Test
{
    using Machines;

    public static class WatchingTvSample
    {
        public enum Status { Unplugged, Off, On, Disposed }

        public class DeviceTransitionAttribute : TransitionAttribute
        {
            public Status From { get; set; }
            public string When { get; set; }
            public Status Goto { get; set; }
            public object With { get; set; }
        }

        // State<Status> is a shortcut for / derived from State<Status, string>,
        // which in turn is a shortcut for / derived from State<Status, string, object> :
        public class Device : State<Status>
        {
            // Executed before and after every state transition :
            protected override void OnChange(ExecutionStep step, Status value, string info, object args)
            {
                if (step == ExecutionStep.EnterState)
                {
                    // 'value' is the state value that we have transitioned FROM :
                    Console.WriteLine("\t{0} -- {1} -> {2}", value, info, this);
                }
            }

            public override string ToString() { return Value.ToString(); }
        }

        // Since 'Device' has no state graph of its own, define one for derived 'Television' :
        [DeviceTransition(From = Status.Unplugged, When = "Plug", Goto = Status.Off)]
        [DeviceTransition(From = Status.Unplugged, When = "Dispose", Goto = Status.Disposed)]
        [DeviceTransition(From = Status.Off, When = "Switch On", Goto = Status.On)]
        [DeviceTransition(From = Status.Off, When = "Unplug", Goto = Status.Unplugged)]
        [DeviceTransition(From = Status.Off, When = "Dispose", Goto = Status.Disposed)]
        [DeviceTransition(From = Status.On, When = "Switch Off", Goto = Status.Off)]
        [DeviceTransition(From = Status.On, When = "Unplug", Goto = Status.Unplugged)]
        [DeviceTransition(From = Status.On, When = "Dispose", Goto = Status.Disposed)]
        public class Television : Device { }

        public static void Run()
        {
            Console.Clear();

            // Create a television state machine instance, and return it, set in some start state :
            var tv = new Television().Start(Status.Unplugged);
            bool done;

            // Holds iff the chosen start state isn't a final state :
            System.Diagnostics.Debug.Assert(tv != null, "The chosen start state is a final state!");

            // Trigger some state transitions with no arguments
            // ('args' is ignored by this state machine's OnChange(...), anyway) :
            done =
                (
                    tv.
                        MoveNext("Plug").
                        MoveNext("Switch On").
                        MoveNext("Switch Off").
                        MoveNext("Switch On").
                        MoveNext("Switch Off").
                        MoveNext("Unplug").
                        MoveNext("Dispose") // MoveNext(...) returns null iff tv.IsFinal == true
                    == null
                );

            Console.WriteLine();
            Console.WriteLine("Is the TV's state '{0}' a final state? {1}", tv.Value, done);

            Console.WriteLine();
            Console.WriteLine("Press any key...");
            Console.ReadKey();
        }
    }
}

'HTH

Testing pointers for validity (C/C++)

It's unbelievable how much misleading information you can read in articles above...

And even in microsoft msdn documentation IsBadPtr is claimed to be banned. Oh well - I prefer working application rather than crashing. Even if term working might be working incorrectly (as long as end-user can continue with application).

By googling I haven't found any useful example for windows - found a solution for 32-bit apps,

http://www.codeproject.com/script/Content/ViewAssociatedFile.aspx?rzp=%2FKB%2Fsystem%2Fdetect-driver%2F%2FDetectDriverSrc.zip&zep=DetectDriverSrc%2FDetectDriver%2Fsrc%2FdrvCppLib%2Frtti.cpp&obid=58895&obtid=2&ovid=2

but I need also to support 64-bit apps, so this solution did not work for me.

But I've harvested wine's source codes, and managed to cook similar kind of code which would work for 64-bit apps as well - attaching code here:

#include <typeinfo.h>   

typedef void (*v_table_ptr)();   

typedef struct _cpp_object   
{   
    v_table_ptr*    vtable;   
} cpp_object;   



#ifndef _WIN64
typedef struct _rtti_object_locator
{
    unsigned int signature;
    int base_class_offset;
    unsigned int flags;
    const type_info *type_descriptor;
    //const rtti_object_hierarchy *type_hierarchy;
} rtti_object_locator;
#else

typedef struct
{
    unsigned int signature;
    int base_class_offset;
    unsigned int flags;
    unsigned int type_descriptor;
    unsigned int type_hierarchy;
    unsigned int object_locator;
} rtti_object_locator;  

#endif

/* Get type info from an object (internal) */  
static const rtti_object_locator* RTTI_GetObjectLocator(void* inptr)  
{   
    cpp_object* cppobj = (cpp_object*) inptr;  
    const rtti_object_locator* obj_locator = 0;   

    if (!IsBadReadPtr(cppobj, sizeof(void*)) &&   
        !IsBadReadPtr(cppobj->vtable - 1, sizeof(void*)) &&   
        !IsBadReadPtr((void*)cppobj->vtable[-1], sizeof(rtti_object_locator)))  
    {  
        obj_locator = (rtti_object_locator*) cppobj->vtable[-1];  
    }  

    return obj_locator;  
}  

And following code can detect whether pointer is valid or not, you need probably to add some NULL checking:

    CTest* t = new CTest();
    //t = (CTest*) 0;
    //t = (CTest*) 0x12345678;

    const rtti_object_locator* ptr = RTTI_GetObjectLocator(t);  

#ifdef _WIN64
    char *base = ptr->signature == 0 ? (char*)RtlPcToFileHeader((void*)ptr, (void**)&base) : (char*)ptr - ptr->object_locator;
    const type_info *td = (const type_info*)(base + ptr->type_descriptor);
#else
    const type_info *td = ptr->type_descriptor;
#endif
    const char* n =td->name();

This gets class name from pointer - I think it should be enough for your needs.

One thing which I'm still afraid is performance of pointer checking - in code snipet above there is already 3-4 API calls being made - might be overkill for time critical applications.

It would be good if someone could measure overhead of pointer checking compared for example to C#/managed c++ calls.

Typescript: React event types

I have the following in a types.ts file for html input, select, and textarea:

export type InputChangeEventHandler = React.ChangeEventHandler<HTMLInputElement>
export type TextareaChangeEventHandler = React.ChangeEventHandler<HTMLTextAreaElement>
export type SelectChangeEventHandler = React.ChangeEventHandler<HTMLSelectElement>

Then import them:

import { InputChangeEventHandler } from '../types'

Then use them:


const updateName: InputChangeEventHandler = (event) => {
  // Do something with `event.currentTarget.value`
}
const updateBio: TextareaChangeEventHandler = (event) => {
  // Do something with `event.currentTarget.value`
}
const updateSize: SelectChangeEventHandler = (event) => {
  // Do something with `event.currentTarget.value`
}

Then apply the functions on your markup (replacing ... with other necessary props):

<input onChange={updateName} ... />
<textarea onChange={updateName} ... />
<select onChange={updateSize} ... >
  // ...
</select>

jQuery autocomplete with callback ajax json

My issue was that end users would start typing in a textbox and receive autocomplete (ACP) suggestions and update the calling control if a suggestion was selected as the ACP is designed by default. However, I also needed to update multiple other controls (textboxes, DropDowns, etc...) with data specific to the end user's selection. I have been trying to figure out an elegant solution to the issue and I feel the one I developed is worth sharing and hopefully will save you at least some time.

WebMethod (SampleWM.aspx):

  • PURPOSE:

    • To capture SQL Server Stored Procedure results and return them as a JSON String to the AJAX Caller
  • NOTES:

    • Data.GetDataTableFromSP() - Is a custom function that returns a DataTable from the results of a Stored Procedure
    • < System.Web.Services.WebMethod(EnableSession:=True) > _
    • Public Shared Function GetAutoCompleteData(ByVal QueryFilterAs String) As String

 //Call to custom function to return SP results as a DataTable
 // DataTable will consist of Field0 - Field5
 Dim params As ArrayList = New ArrayList
 params.Add("@QueryFilter|" & QueryFilter)
 Dim dt As DataTable = Data.GetDataTableFromSP("AutoComplete", params, [ConnStr])

 //Create a StringBuilder Obj to hold the JSON 
 //IE: [{"Field0":"0","Field1":"Test","Field2":"Jason","Field3":"Smith","Field4":"32","Field5":"888-555-1212"},{"Field0":"1","Field1":"Test2","Field2":"Jane","Field3":"Doe","Field4":"25","Field5":"888-555-1414"}]
 Dim jStr As StringBuilder = New StringBuilder

 //Loop the DataTable and convert row into JSON String
 If dt.Rows.Count > 0 Then
      jStr.Append("[")
      Dim RowCnt As Integer = 1
      For Each r As DataRow In dt.Rows
           jStr.Append("{")
           Dim ColCnt As Integer = 0
           For Each c As DataColumn In dt.Columns
               If ColCnt = 0 Then
                   jStr.Append("""" & c.ColumnName & """:""" & r(c.ColumnName) & """")
               Else
                   jStr.Append(",""" & c.ColumnName & """:""" & r(c.ColumnName) & """")
                End If
                ColCnt += 1
            Next

            If Not RowCnt = dt.Rows.Count Then
                jStr.Append("},")
            Else
                jStr.Append("}")
            End If

            RowCnt += 1
        Next

        jStr.Append("]")
    End If

    //Return JSON to WebMethod Caller
    Return jStr.ToString

AutoComplete jQuery (AutoComplete.aspx):

  • PURPOSE:
    • Perform the Ajax Request to the WebMethod and then handle the response

    $(function() {
      $("#LookUp").autocomplete({                
            source: function (request, response) {
                $.ajax({
                    type: "POST",
                    contentType: "application/json; charset=utf-8",
                    url: "SampleWM.aspx/GetAutoCompleteData",
                    dataType: "json",
                    data:'{QueryFilter: "' + request.term  + '"}',
                    success: function (data) {
                        response($.map($.parseJSON(data.d), function (item) {                                
                            var AC = new Object();

                            //autocomplete default values REQUIRED
                            AC.label = item.Field0;
                            AC.value = item.Field1;

                            //extend values
                            AC.FirstName = item.Field2;
                            AC.LastName = item.Field3;
                            AC.Age = item.Field4;
                            AC.Phone = item.Field5;

                            return AC
                        }));       
                    }                                             
                });
            },
            minLength: 3,
            select: function (event, ui) {                    
                $("#txtFirstName").val(ui.item.FirstName);
                $("#txtLastName").val(ui.item.LastName);
                $("#ddlAge").val(ui.item.Age);
                $("#txtPhone").val(ui.item.Phone);
             }                    
        });
     });

How to get Top 5 records in SqLite?

select price from mobile_sales_details order by price desc limit 5

Note: i have mobile_sales_details table

syntax

select column_name from table_name order by column_name desc limit size.  

if you need top low price just remove the keyword desc from order by

Using Exit button to close a winform program

If you only want to Close the form than you can use this.Close(); else if you want the whole application to be closed use Application.Exit();

pandas: How do I split text in a column into multiple rows?

Can also use groupby() with no need to join and stack().

Use above example data:

import pandas as pd
import numpy as np


df = pd.DataFrame({'ItemQty': {0: 3, 1: 25}, 
                   'Seatblocks': {0: '2:218:10:4,6', 1: '1:13:36:1,12 1:13:37:1,13'}, 
                   'ItemExt': {0: 60, 1: 300}, 
                   'CustomerName': {0: 'McCartney, Paul', 1: 'Lennon, John'}, 
                   'CustNum': {0: 32363, 1: 31316}, 
                   'Item': {0: 'F04', 1: 'F01'}}, 
                    columns=['CustNum','CustomerName','ItemQty','Item','Seatblocks','ItemExt']) 
print(df)

   CustNum     CustomerName  ItemQty Item                 Seatblocks  ItemExt
0  32363    McCartney, Paul  3        F04  2:218:10:4,6               60     
1  31316    Lennon, John     25       F01  1:13:36:1,12 1:13:37:1,13  300  


#first define a function: given a Series of string, split each element into a new series
def split_series(ser,sep):
    return pd.Series(ser.str.cat(sep=sep).split(sep=sep)) 
#test the function, 
split_series(pd.Series(['a b','c']),sep=' ')
0    a
1    b
2    c
dtype: object

df2=(df.groupby(df.columns.drop('Seatblocks').tolist()) #group by all but one column
          ['Seatblocks'] #select the column to be split
          .apply(split_series,sep=' ') # split 'Seatblocks' in each group
         .reset_index(drop=True,level=-1).reset_index()) #remove extra index created

print(df2)
   CustNum     CustomerName  ItemQty Item  ItemExt    Seatblocks
0    31316     Lennon, John       25  F01      300  1:13:36:1,12
1    31316     Lennon, John       25  F01      300  1:13:37:1,13
2    32363  McCartney, Paul        3  F04       60  2:218:10:4,6

Why am I getting "Unable to find manifest signing certificate in the certificate store" in my Excel Addin?

When the project was originally created, the click-once signing certificate was added on the signing tab of the project's properties. This signs the click-once manifest when you build it. Between then and now, that certificate is no longer available. Either this wasn't the machine you originally built it on or it got cleaned up somehow. You need to re-add that certificate to your machine or chose another certificate.

Is the sizeof(some pointer) always equal to four?

Size of pointer and int is 2 bytes in Turbo C compiler on windows 32 bit machine.

So size of pointer is compiler specific. But generally most of the compilers are implemented to support 4 byte pointer variable in 32 bit and 8 byte pointer variable in 64 bit machine).

So size of pointer is not same in all machines.

Find a value in an array of objects in Javascript

As per ECMAScript 6, you can use the findIndex function.

array[array.findIndex(x => x.name == 'string 1')]

Default value of function parameter

In C++ the requirements imposed on default arguments with regard to their location in parameter list are as follows:

  1. Default argument for a given parameter has to be specified no more than once. Specifying it more than once (even with the same default value) is illegal.

  2. Parameters with default arguments have to form a contiguous group at the end of the parameter list.

Now, keeping that in mind, in C++ you are allowed to "grow" the set of parameters that have default arguments from one declaration of the function to the next, as long as the above requirements are continuously satisfied.

For example, you can declare a function with no default arguments

void foo(int a, int b);

In order to call that function after such declaration you'll have to specify both arguments explicitly.

Later (further down) in the same translation unit, you can re-declare it again, but this time with one default argument

void foo(int a, int b = 5);

and from this point on you can call it with just one explicit argument.

Further down you can re-declare it yet again adding one more default argument

void foo(int a = 1, int b);

and from this point on you can call it with no explicit arguments.

The full example might look as follows

void foo(int a, int b);

int main()
{
  foo(2, 3);

  void foo(int a, int b = 5); // redeclare
  foo(8); // OK, calls `foo(8, 5)`

  void foo(int a = 1, int b); // redeclare again
  foo(); // OK, calls `foo(1, 5)`
}

void foo(int a, int b)
{
  // ...
}

As for the code in your question, both variants are perfectly valid, but they mean different things. The first variant declares a default argument for the second parameter right away. The second variant initially declares your function with no default arguments and then adds one for the second parameter.

The net effect of both of your declarations (i.e. the way it is seen by the code that follows the second declaration) is exactly the same: the function has default argument for its second parameter. However, if you manage to squeeze some code between the first and the second declarations, these two variants will behave differently. In the second variant the function has no default arguments between the declarations, so you'll have to specify both arguments explicitly.

DataGridView.Clear()

Try this Method

dataGridView1.DataSource = dt;
dt.Rows.Clear();

How to handle static content in Spring MVC?

I solved it this way:

<servlet-mapping>
    <servlet-name>Spring MVC Dispatcher Servlet</servlet-name>
    <url-pattern>/</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>default</servlet-name>
    <url-pattern>*.jpg</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>default</servlet-name>
    <url-pattern>*.png</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>default</servlet-name>
    <url-pattern>*.gif</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>default</servlet-name>
    <url-pattern>*.js</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>default</servlet-name>
    <url-pattern>*.css</url-pattern>
</servlet-mapping>

This works on Tomcat and ofcourse Jboss. However in the end I decided to use the solution Spring provides (as mentioned by rozky) which is far more portable.

How to send an object from one Android Activity to another using Intents?

You'll need to serialize your object into some kind of string representation. One possible string representation is JSON, and one of the easiest ways to serialize to/from JSON in android, if you ask me, is through Google GSON.

In that case you just put the string return value from (new Gson()).toJson(myObject); and retrieve the string value and use fromJson to turn it back into your object.

If your object isn't very complex, however, it might not be worth the overhead, and you could consider passing the separate values of the object instead.

How to get Last record from Sqlite?

Also, if your table has no ID column, or sorting by id doesn't return you the last row, you can always use sqlite schema native 'rowid' field.

SELECT column 
FROM table 
WHERE rowid = (SELECT MAX(rowid) FROM table);

Pandas: convert dtype 'object' to int

pandas >= 1.0

convert_dtypes

The (self) accepted answer doesn't take into consideration the possibility of NaNs in object columns.

df = pd.DataFrame({
     'a': [1, 2, np.nan], 
     'b': [True, False, np.nan]}, dtype=object) 
df                                                                         

     a      b
0    1   True
1    2  False
2  NaN    NaN

df['a'].astype(str).astype(int) # raises ValueError

This chokes because the NaN is converted to a string "nan", and further attempts to coerce to integer will fail. To avoid this issue, we can soft-convert columns to their corresponding nullable type using convert_dtypes:

df.convert_dtypes()                                                        

      a      b
0     1   True
1     2  False
2  <NA>   <NA>

df.convert_dtypes().dtypes                                                 

a      Int64
b    boolean
dtype: object

If your data has junk text mixed in with your ints, you can use pd.to_numeric as an initial step:

s = pd.Series(['1', '2', '...'])
s.convert_dtypes()  # converts to string, which is not what we want

0      1
1      2
2    ...
dtype: string 

# coerces non-numeric junk to NaNs
pd.to_numeric(s, errors='coerce')

0    1.0
1    2.0
2    NaN
dtype: float64

# one final `convert_dtypes` call to convert to nullable int
pd.to_numeric(s, errors='coerce').convert_dtypes() 

0       1
1       2
2    <NA>
dtype: Int64

Multiline input form field using Bootstrap

The answer by Nick Mitchinson is for Bootstrap version 2.

If you are using Bootstrap version 3, then forms have changed a bit. For bootstrap 3, use the following instead:

<div class="form-horizontal">
    <div class="form-group">
        <div class="col-md-6">
            <textarea class="form-control" rows="3" placeholder="What's up?" required></textarea>
        </div>
    </div>
</div>

Where, col-md-6 will target medium sized devices. You can add col-xs-6 etc to target smaller devices.

Bootstrap: how do I change the width of the container?

Set your own content container class with 1000px width property and then use container-fluid boostrap class instead of container.

Works but might not be the best solution.

How do I give PHP write access to a directory?

Simple 3-Step Solution

Abstract: You need to set the owner of the directory to the user that PHP uses (web server user).


Step 1: Determine PHP User

Create a PHP file containing the following:

<?php echo `whoami`; ?>

Upload it to your web server. The output should be similar to the following:

www-data

Therefore, the PHP user is www-data.


Step 2: Determine Owner of Directory

Next, check the details of the web directory via the command line:

ls -dl /var/www/example.com/public_html/example-folder

The result should be similar to the following:

drwxrwxr-x 2 exampleuser1 exampleuser2 4096 Mar 29 16:34 example-folder

Therefore, the owner of the directory is exampleuser1.


Step 3: Change Directory Owner to PHP User

Afterwards, change the owner of the web directory to the PHP user:

sudo chown -R www-data /var/www/example.com/public_html/example-folder

Verify that the owner of the web directory has been changed:

ls -dl /var/www/example.com/public_html/example-folder

The result should be similar to the following:

drwxrwxr-x 2 www-data exampleuser2 4096 Mar 29 16:34 example-folder

Therefore, the owner of example-folder has successfully been changed to the PHP user: www-data.


Done! PHP should now be able to write to the directory.

WHERE IS NULL, IS NOT NULL or NO WHERE clause depending on SQL Server parameter value

WHERE MyColumn = COALESCE(@value,MyColumn) 
  • If @value is NULL, it will compare MyColumn to itself, ignoring @value = no where clause.

  • IF @value has a value (NOT NULL) it will compare MyColumn to @value.

Reference: COALESCE (Transact-SQL).

Auto Scale TextView Text to Fit within Bounds

You can use the android.text.StaticLayout class for this. That's what TextView uses internally.

C# - Print dictionary

There's more than one way to skin this problem so here's my solution:

  1. Use Select() to convert the key-value pair to a string;
  2. Convert to a list of strings;
  3. Write out to the console using ForEach().
dict.Select(i => $"{i.Key}: {i.Value}").ToList().ForEach(Console.WriteLine);

OpenSSL Verify return code: 20 (unable to get local issuer certificate)

this error messages means that CABundle is not given by (-CAfile ...) OR the CABundle file is not closed by a self-signed root certificate.

Don't worry. The connection to server will work even you get theis message from openssl s_client ... (assumed you dont take other mistake too)

Unable to verify leaf signature

If you come to this thread because you're using the node postgres / pg module, there is a better solution than setting NODE_TLS_REJECT_UNAUTHORIZED or rejectUnauthorized, which will lead to insecure connections.

Instead, configure the "ssl" option to match the parameters for tls.connect:

{
  ca: fs.readFileSync('/path/to/server-ca.pem').toString(),
  cert: fs.readFileSync('/path/to/client-cert.pem').toString(),
  key: fs.readFileSync('/path/to/client-key.pem').toString(),
  servername: 'my-server-name' // e.g. my-project-id/my-sql-instance-id for Google SQL
}

I've written a module to help with parsing these options from environment variables like PGSSLROOTCERT, PGSSLCERT, and PGSSLKEY:

https://github.com/programmarchy/pg-ssl

append multiple values for one key in a dictionary

You would be best off using collections.defaultdict (added in Python 2.5). This allows you to specify the default object type of a missing key (such as a list).

So instead of creating a key if it doesn't exist first and then appending to the value of the key, you cut out the middle-man and just directly append to non-existing keys to get the desired result.

A quick example using your data:

>>> from collections import defaultdict
>>> data = [(2010, 2), (2009, 4), (1989, 8), (2009, 7)]
>>> d = defaultdict(list)
>>> d
defaultdict(<type 'list'>, {})
>>> for year, month in data:
...     d[year].append(month)
... 
>>> d
defaultdict(<type 'list'>, {2009: [4, 7], 2010: [2], 1989: [8]})

This way you don't have to worry about whether you've seen a digit associated with a year or not. You just append and forget, knowing that a missing key will always be a list. If a key already exists, then it will just be appended to.

How to access PHP session variables from jQuery function in a .js file?

You can pass you session variables from your php script to JQUERY using JSON such as

JS:

jQuery("#rowed2").jqGrid({
    url:'yourphp.php?q=3', 
    datatype: "json", 
    colNames:['Actions'], 
    colModel:[{
                name:'Actions',
                index:'Actions', 
                width:155,
                sortable:false
              }], 
    rowNum:30, 
    rowList:[50,100,150,200,300,400,500,600], 
    pager: '#prowed2', 
    sortname: 'id',
    height: 660,        
    viewrecords: true, 
    sortorder: 'desc',
    gridview:true,
    editurl: 'yourphp.php', 
    caption: 'Caption', 
    gridComplete: function() { 
        var ids = jQuery("#rowed2").jqGrid('getDataIDs'); 
        for (var i = 0; i < ids.length; i++) { 
            var cl = ids[i]; 
            be = "<input style='height:22px;width:50px;' `enter code here` type='button' value='Edit' onclick=\"jQuery('#rowed2').editRow('"+cl+"');\" />"; 
            se = "<input style='height:22px;width:50px;' type='button' value='Save' onclick=\"jQuery('#rowed2').saveRow('"+cl+"');\" />"; 
            ce = "<input style='height:22px;width:50px;' type='button' value='Cancel' onclick=\"jQuery('#rowed2').restoreRow('"+cl+"');\" />"; 
            jQuery("#rowed2").jqGrid('setRowData', ids[i], {Actions:be+se+ce}); 
        } 
    }
}); 

PHP

// start your session
session_start();

// get session from database or create you own
$session_username = $_SESSION['John'];
$session_email = $_SESSION['[email protected]'];

$response = new stdClass();
$response->session_username = $session_username;
$response->session_email = $session_email;

$i = 0;
while ($row = mysqli_fetch_array($result)) { 
    $response->rows[$i]['id'] = $row['ID']; 
    $response->rows[$i]['cell'] = array("", $row['rowvariable1'], $row['rowvariable2']); 
    $i++; 
} 

echo json_encode($response);
// this response (which contains your Session variables) is sent back to your JQUERY 

How do I format a String in an email so Outlook will print the line breaks?

If you can add in a '.' (dot) character at the end of each line, this seems to prevent Outlook ruining text formatting.

How to start a stopped Docker container with a different command?

Find your stopped container id

docker ps -a

Commit the stopped container:

This command saves modified container state into a new image user/test_image

docker commit $CONTAINER_ID user/test_image

Start/run with a different entry point:

docker run -ti --entrypoint=sh user/test_image

Entrypoint argument description: https://docs.docker.com/engine/reference/run/#/entrypoint-default-command-to-execute-at-runtime

Note:

Steps above just start a stopped container with the same filesystem state. That is great for a quick investigation. But environment variables, network configuration, attached volumes and other staff is not inherited, you should specify all these arguments explicitly.

Steps to start a stopped container have been borrowed from here: (last comment) https://github.com/docker/docker/issues/18078

PHP Warning: PHP Startup: ????????: Unable to initialize module

This is an old thread, but I stumbled across it when trying to solve a similar problem.

For me, I got this particular error relating to the php_wincache.dll. I was in the process of updating PHP from 5.5.38 to 5.6.31 on a Windows server. For some reason, not all of the DLL files updated with the newest versions. Most did, but some didn't.

So, if you get an error similar to this, make sure all the extensions are in place and updated.

Toad for Oracle..How to execute multiple statements?

I prefer the Execute via SQL*Plus option. It's in the little down-arrow menu under the "Execute as script" toolbar button.

Determine which element the mouse pointer is on top of in JavaScript

DEMO

There's a really cool function called document.elementFromPoint which does what it sounds like.

What we need is to find the x and y coords of the mouse and then call it using those values:

var x = event.clientX, y = event.clientY,
    elementMouseIsOver = document.elementFromPoint(x, y);

document.elementFromPoint

jQuery event object

Keylistener in Javascript

Did you check the small Mousetrap library?

Mousetrap is a simple library for handling keyboard shortcuts in JavaScript.

How can I query a value in SQL Server XML column

declare @T table(Roles xml)

insert into @T values
('<root>
   <role>Alpha</role>
   <role>Beta</role>
   <role>Gamma</role>
</root>')

declare @Role varchar(10)

set @Role = 'Beta'

select Roles
from @T
where Roles.exist('/root/role/text()[. = sql:variable("@Role")]') = 1

If you want the query to work as where col like '%Beta%' you can use contains

declare @T table(Roles xml)

insert into @T values
('<root>
   <role>Alpha</role>
   <role>Beta</role>
   <role>Gamma</role>
</root>')

declare @Role varchar(10)

set @Role = 'et'

select Roles
from @T
where Roles.exist('/root/role/text()[contains(., sql:variable("@Role"))]') = 1

Package signatures do not match the previously installed version

In my case the issue was I had installed an app with the package name let's say com.example.package using android studio on my device. I created another app with the same package name and was trying to install it on my device. That is what was causing the problem. So just check on your device whether another app with the same package name already exists or not.

importing external ".txt" file in python

As you can't import a .txt file, I would suggest to read words this way.

list_ = open("world.txt").read().split()

make html text input field grow as I type?

For those strictly looking for a solution that works for input or textarea, this is the simplest solution I've came across. Only a few lines of CSS and one line of JS.

The JavaScript sets a data-* attribute on the element equal to the value of the input. The input is set within a CSS grid, where that grid is a pseudo-element that uses that data-* attribute as its content. That content is what stretches the grid to the appropriate size based on the input value.

DOS: find a string, if found then run another script

As the answer is marked correct then it's a Windows Dos prompt script and this will work too:

find "string" status.txt >nul && call "my batch file.bat"

Set and Get Methods in java?

Setters and getters are used to replace directly accessing member variables from external classes. if you use a setter and getter in accessing a property, you can include initialization, error checking, complex transformations, etc. Some examples:

private String x;

public void setX(String newX) {
    if (newX == null) {
        x = "";
    } else {
        x = newX;
    }
}

public String getX() {
    if (x == null) {
        return "";
    } else {
       return x;
    }
}

Setting state on componentDidMount()

The only reason that the linter complains about using setState({..}) in componentDidMount and componentDidUpdate is that when the component render the setState immediately causes the component to re-render. But the most important thing to note: using it inside these component's lifecycles is not an anti-pattern in React.

Please take a look at this issue. you will understand more about this topic. Thanks for reading my answer.

Provide an image for WhatsApp link sharing

I guess there is no white list in whatsapp, as I found a solution that worked for me. Do as follows. insert 3 meta tags:

<meta property="og:image" content="http://yourimage_with_complete_URL.png"/>  
<meta property="og:title" content="Your Title"/>  
<meta property="og:description" content="Your description."/>  

Your image must be in .png format and 600x600px dimension and must be named 'logo-yoursite.png' (once it worked for me JUST LIKE THAT)

Dont forget to insert the link to whatsapp in your website:

<a href='whatsapp://send?text=Text to send withe message: http://www.yoursite.com'>whatsApp</a>

Do this and you'll be well done!

How to Use Multiple Columns in Partition By And Ensure No Duplicate Row is Returned

I'd create a cte and do an inner join. It's not efficient but it's convenient

with table as (
SELECT DATE, STATUS, TITLE, ROW_NUMBER() 
OVER (PARTITION BY DATE, STATUS,  TITLE ORDER BY QUANTITY ASC) AS Row_Num
 FROM TABLE)

select *

from table t
join select(
max(Row_Num) as Row_Num
,DATE
,STATUS
,TITLE
from table 
group by date, status, title) t2  
on t2.Row_Num = t.Row_Num and t2
and t2.date = t.date
and t2.title = t.title

Error "can't use subversion command line client : svn" when opening android project checked out from svn

If you using windows, you can fix it via install SVN Tool. If you using Linux/MacOS, you can fix it via install subversion. After that, just select using svn command. Your problems is resolve.

How to convert char to int?

int val = '1' & 15;

The binary of the ASCII charecters 0-9 is:

0   -   00110000

1   -   00110001

2   -   00110010

3   -   00110011

4   -   00110100

5   -   00110101

6   -   00110110

7   -   00110111

8   -   00111000

9   -   00111001

and if you take in each one of them the first 4 LSB(using bitwise AND with 8'b00001111 that equels to 15) you get the actual number (0000 = 0,0001=1,0010=2,... )

Why am I getting an error "Object literal may only specify known properties"?

As of TypeScript 1.6, properties in object literals that do not have a corresponding property in the type they're being assigned to are flagged as errors.

Usually this error means you have a bug (typically a typo) in your code, or in the definition file. The right fix in this case would be to fix the typo. In the question, the property callbackOnLoactionHash is incorrect and should have been callbackOnLocationHash (note the mis-spelling of "Location").

This change also required some updates in definition files, so you should get the latest version of the .d.ts for any libraries you're using.

Example:

interface TextOptions {
    alignment?: string;
    color?: string;
    padding?: number;
}
function drawText(opts: TextOptions) { ... }
drawText({ align: 'center' }); // Error, no property 'align' in 'TextOptions'

But I meant to do that

There are a few cases where you may have intended to have extra properties in your object. Depending on what you're doing, there are several appropriate fixes

Type-checking only some properties

Sometimes you want to make sure a few things are present and of the correct type, but intend to have extra properties for whatever reason. Type assertions (<T>v or v as T) do not check for extra properties, so you can use them in place of a type annotation:

interface Options {
    x?: string;
    y?: number;
}

// Error, no property 'z' in 'Options'
let q1: Options = { x: 'foo', y: 32, z: 100 };
// OK
let q2 = { x: 'foo', y: 32, z: 100 } as Options;
// Still an error (good):
let q3 = { x: 100, y: 32, z: 100 } as Options;

These properties and maybe more

Some APIs take an object and dynamically iterate over its keys, but have 'special' keys that need to be of a certain type. Adding a string indexer to the type will disable extra property checking

Before

interface Model {
  name: string;
}
function createModel(x: Model) { ... }

// Error
createModel({name: 'hello', length: 100});

After

interface Model {
  name: string;
  [others: string]: any;
}
function createModel(x: Model) { ... }

// OK
createModel({name: 'hello', length: 100});

This is a dog or a cat or a horse, not sure yet

interface Animal { move; }
interface Dog extends Animal { woof; }
interface Cat extends Animal { meow; }
interface Horse extends Animal { neigh; }

let x: Animal;
if(...) {
  x = { move: 'doggy paddle', woof: 'bark' };
} else if(...) {
  x = { move: 'catwalk', meow: 'mrar' };
} else {
  x = { move: 'gallop', neigh: 'wilbur' };
}

Two good solutions come to mind here

Specify a closed set for x

// Removes all errors
let x: Dog|Cat|Horse;

or Type assert each thing

// For each initialization
  x = { move: 'doggy paddle', woof: 'bark' } as Dog;

This type is sometimes open and sometimes not

A clean solution to the "data model" problem using intersection types:

interface DataModelOptions {
  name?: string;
  id?: number;
}
interface UserProperties {
  [key: string]: any;
}
function createDataModel(model: DataModelOptions & UserProperties) {
 /* ... */
}
// findDataModel can only look up by name or id
function findDataModel(model: DataModelOptions) {
 /* ... */
}
// OK
createDataModel({name: 'my model', favoriteAnimal: 'cat' });
// Error, 'ID' is not correct (should be 'id')
findDataModel({ ID: 32 });

See also https://github.com/Microsoft/TypeScript/issues/3755

setTimeout or setInterval?

To look at it a bit differently: setInterval insures that a code is run at every given interval (i.e. 1000ms, or how much you specify) while setTimeout sets the time that it 'waits until' it runs the code. And since it takes extra milliseconds to run the code, it adds up to 1000ms and thus, setTimeout runs again at inexact times (over 1000ms).

For example, timers/countdowns are not done with setTimeout, they are done with setInterval, to ensure it does not delay and the code runs at the exact given interval.

How can I make a jQuery UI 'draggable()' div draggable for touchscreen?

I was struggling with a similar problem yesterday. I already had a "working" solution using jQuery UI's draggable together with jQuery Touch Punch, which are mentioned in other answers. However, using this method was causing weird bugs in some Android devices for me, and therefore I decided to write a small jQuery plugin that can make HTML elements draggable by using touch events instead of using a method that emulates fake mouse events.

The result of this is jQuery Draggable Touch which is a simple jQuery plugin for making elements draggable, that has touch devices as it's main target by using touch events (like touchstart, touchmove, touchend, etc.). It still has a fallback that uses mouse events if the browser/device doesn't support touch events.

How to return the current timestamp with Moment.js?

Try this

console.log(moment().format("MM ddd, YYYY HH:mm:ss a"));

_x000D_
_x000D_
console.log(moment().format("MM ddd, YYYY hh:mm:ss a"));
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.22.1/moment.min.js"></script>
_x000D_
_x000D_
_x000D_

Count length of array and return 1 if it only contains one element

A couple other options:

  1. Use the comma operator to create an array:

    $cars = ,"bmw"
    $cars.GetType().FullName
    # Outputs: System.Object[]
    
  2. Use array subexpression syntax:

    $cars = @("bmw")
    $cars.GetType().FullName
    # Outputs: System.Object[]
    

If you don't want an object array you can downcast to the type you want e.g. a string array.

 [string[]] $cars = ,"bmw"
 [string[]] $cars = @("bmw")

How can I output UTF-8 from Perl?

Thanks, finally got an solution to not put utf8::encode all over code. To synthesize and complete for other cases, like write and read files in utf8 and also works with LoadFile of an YAML file in utf8

use utf8;
use open ':encoding(utf8)';
binmode(STDOUT, ":utf8");

open(FH, ">test.txt"); 
print FH "something éá";

use YAML qw(LoadFile Dump);
my $PUBS = LoadFile("cache.yaml");
my $f = "2917";
my $ref = $PUBS->{$f};
print "$f \"".$ref->{name}."\" ". $ref->{primary_uri}." ";

where cache.yaml is:

---
2917:
  id: 2917
  name: Semanário
  primary_uri: 2917.xml

SQL Server : SUM() of multiple rows including where clauses

The WHERE clause is always conceptually applied (the execution plan can do what it wants, obviously) prior to the GROUP BY. It must come before the GROUP BY in the query, and acts as a filter before things are SUMmed, which is how most of the answers here work.

You should also be aware of the optional HAVING clause which must come after the GROUP BY. This can be used to filter on the resulting properties of groups after GROUPing - for instance HAVING SUM(Amount) > 0

How to set HttpResponse timeout for Android in Java

An option is to use the OkHttp client, from Square.

Add the library dependency

In the build.gradle, include this line:

compile 'com.squareup.okhttp:okhttp:x.x.x'

Where x.x.x is the desired library version.

Set the client

For example, if you want to set a timeout of 60 seconds, do this way:

final OkHttpClient okHttpClient = new OkHttpClient();
okHttpClient.setReadTimeout(60, TimeUnit.SECONDS);
okHttpClient.setConnectTimeout(60, TimeUnit.SECONDS);

ps: If your minSdkVersion is greater than 8, you can use TimeUnit.MINUTES. So, you can simply use:

okHttpClient.setReadTimeout(1, TimeUnit.MINUTES);
okHttpClient.setConnectTimeout(1, TimeUnit.MINUTES);

For more details about the units, see TimeUnit.

Is there a way to reduce the size of the git folder?

One scenario where your git repo will get seriously bigger with each commit is one where you are committing binary files that you generate regularly. Their storage won't be as efficient than text file.

Another is one where you have a huge number of files within one repo (which is a limit of git) instead of several subrepos (managed as submodules).

In this article on git space, AlBlue mentions:

Note that Git (and Hg, and other DVCSs) do suffer from a problem where (large) binaries are checked in, then deleted, as they'll still show up in the repository and take up space, even if they're not current.

If you have large binaries stored in your git repo, you may consider:

As I mentioned in "What are the file limits in Git (number and size)?", the more recent (2015, 5 years after this answer) Git LFS from GitHub is a way to manage those large files (by storing them outside the Git repository).

How do I detect what .NET Framework versions and service packs are installed?

I wanted to detect for the presence of .NET version 4.5.2 installed on my system, and I found no better solution than ASoft .NET Version Detector.

Snapshot of this tool showing different .NET versions:

Snapshot of this tool showing different .NET versions

Array formula on Excel for Mac

CTRL+SHIFT+ENTER, ARRAY FORMULA EXCEL 2016 MAC. So I arrive late into the game, but maybe someone else will. This almost drove me nuts. No matter what I searched for in Google I came up empty. Whatever I tried, no solution seemed to be in sight. Switched to Excel 2016 quite some time ago and today I needed to do some array formulas. Also sitting on a MacBook Pro 15 Touch Bar 2016. Not that it really matters, but still, since the solution was published on Youtube in 2013. The reason why, for me anyway, nothing worked, is in the Mac OS, the control key by default, for me anyway, is set to manage Mission control, which, at least for me, disabled the control button in Excel. In order to enable the key to actually control functions in Excel, you need to go to System preferences > Mission Control, and disable shortcuts for Mission control. So, let's see how long this solution will last. Probably be back to square one after the coffee break. Have a good one!

matplotlib colorbar in each subplot

Try to use the func below to add colorbar:

def add_colorbar(mappable):
    from mpl_toolkits.axes_grid1 import make_axes_locatable
    import matplotlib.pyplot as plt
    last_axes = plt.gca()
    ax = mappable.axes
    fig = ax.figure
    divider = make_axes_locatable(ax)
    cax = divider.append_axes("right", size="5%", pad=0.05)
    cbar = fig.colorbar(mappable, cax=cax)
    plt.sca(last_axes)
    return cbar

Then you codes need to be modified as:

fig , ( (ax1,ax2) , (ax3,ax4)) = plt.subplots(2, 2,sharex = True,sharey=True)
z1_plot = ax1.scatter(x,y,c = z1,vmin=0.0,vmax=0.4)
add_colorbar(z1_plot)

How to convert std::string to LPCSTR?

str.c_str() gives you a const char *, which is an LPCSTR (Long Pointer to Constant STRing) -- means that it's a pointer to a 0 terminated string of characters. W means wide string (composed of wchar_t instead of char).

How to Remove the last char of String in C#?

newString = yourString.Substring(0, yourString.length -1);

File Upload with Angular Material

Another hacked solution, though might be a little cleaner by implementing a Proxy button:

HTML:

<input id="fileInput" type="file">
<md-button class="md-raised" ng-click="upload()">
  <label>AwesomeButtonName</label>
</md-button>

JS:

app.controller('NiceCtrl', function ( $scope) {
  $scope.upload = function () {
    angular.element(document.querySelector('#fileInput')).click();
  };
};

CMake unable to determine linker language with C++

A bit unrelated answer to OP but for people like me with a somewhat similar problem.

Use Case: Ubuntu (C, Clion, Auto-completion):

I had the same error,

CMake Error: Cannot determine link language for target "hello".

set_target_properties(hello PROPERTIES LINKER_LANGUAGE C) help fixes that problem but the headers aren't included to the project and the autocompletion wont work.

This is what i had

cmake_minimum_required(VERSION 3.5)

project(hello)

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")

set(SOURCE_FILES ./)

add_executable(hello ${SOURCE_FILES})

set_target_properties(hello PROPERTIES LINKER_LANGUAGE C)

No errors but not what i needed, i realized including a single file as source will get me autocompletion as well as it will set the linker to C.

cmake_minimum_required(VERSION 3.5)

project(hello)

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")

set(SOURCE_FILES ./1_helloworld.c)

add_executable(hello ${SOURCE_FILES})

What does "fatal: bad revision" mean?

Why are you specifying myFile there?

Git revert reverts the commit(s) that you specify.

git revert HEAD~2

reverts the HEAD~2 commit

git revert HEAD~2 myfile

reverts HEAD~2 AND myFile

I take myFile is a file that you want to revert? In that case use

git checkout HEAD~2 -- myFile

How can I extract embedded fonts from a PDF as valid font files?

This is a followup to the font-forge section of @Kurt Pfeifle's answer, specific to Red Hat (and possibly other Linux distros).

  1. After opening the PDF and selecting the font you want, you will want to select "File -> Generate Fonts..." option.
  2. If there are errors in the file, you can choose to ignore them or save the file and edit them. Most of the errors can be fixed automatically if you click "Fix" enough times.
  3. Click "Element -> Font Info...", and "Fontname", "Family Name" and "Name for Humans" are all set to values you like. If not, modify them and save the file somewhere. These names will determine how your font appears on the system.
  4. Select your file name and click "Save..."

Once you have your TTF file, you can install it on your system by

  1. Copying it to folder /usr/share/fonts (as root)
  2. Running fc-cache -f /usr/share/fonts/ (as root)

What is a simple command line program or script to backup SQL server databases?

If you can find the DB files... "cp DBFiles backup/"

Almost for sure not advisable in most cases, but it's simple as all getup.

How to print a string in C++

You need #include<string> to use string AND #include<iostream> to use cin and cout. (I didn't get it when I read the answers). Here's some code which works:

#include<string>
#include<iostream>
using namespace std;

int main()
{
    string name;
    cin >> name;
    string message("hi");
    cout << name << message;
    return 0;
}

Test if object implements interface

Using the is or as operators is the correct way if you know the interface type at compile time and have an instance of the type you are testing. Something that no one else seems to have mentioned is Type.IsAssignableFrom:

if( typeof(IMyInterface).IsAssignableFrom(someOtherType) )
{
}

I think this is much neater than looking through the array returned by GetInterfaces and has the advantage of working for classes as well.

Datagridview: How to set a cell in editing mode?

Setting the CurrentCell and then calling BeginEdit(true) works well for me.

The following code shows an eventHandler for the KeyDown event that sets a cell to be editable.

My example only implements one of the required key press overrides but in theory the others should work the same. (and I'm always setting the [0][0] cell to be editable but any other cell should work)

    private void dataGridView1_KeyDown(object sender, KeyEventArgs e)
    {
        if (e.KeyCode == Keys.Tab && dataGridView1.CurrentCell.ColumnIndex == 1)
        {
            e.Handled = true;
            DataGridViewCell cell = dataGridView1.Rows[0].Cells[0];
            dataGridView1.CurrentCell = cell;
            dataGridView1.BeginEdit(true);               
        }
    }

If you haven't found it previously, the DataGridView FAQ is a great resource, written by the program manager for the DataGridView control, which covers most of what you could want to do with the control.

Ignore Duplicates and Create New List of Unique Values in Excel

There is a good guide of how to do this here.

Basically Something similar to:

=INDEX(Sheet1!$A$1:$A$20, MATCH(0, COUNTIF($B$1:B1,Sheet!$A$1:$A$20), 0))

how to release localhost from Error: listen EADDRINUSE

I created 2 servers, listening on same port 8081, running from same code, while learning

1st server creation shud have worked 2nd server creation failed with EADDRINUSE

node.js callback delays might be reason behind neither worked, or 2nd server creation had exception, and program exited, so 1st server is also closed

2 server issue hint, I got from: How to fix Error: listen EADDRINUSE while using nodejs?

Java ArrayList for integers

you should not use Integer[] array inside the list as arraylist itself is a kind of array. Just leave the [] and it should work

Remove columns from DataTable in C#

Aside from limiting the columns selected to reduce bandwidth and memory:

DataTable t;
t.Columns.Remove("columnName");
t.Columns.RemoveAt(columnIndex);

Prevent RequireJS from Caching Required Scripts

Quick Fix for Development

For development, you could just disable the cache in Chrome Dev Tools (Disabling Chrome cache for website development). The cache disabling happens only if the dev tools dialog is open, so you need not worry about toggling this option every time you do regular browsing.

Note: Using 'urlArgs' is the proper solution in production so that users get the latest code. But it makes debugging difficult because chrome invalidates breakpoints with every refresh (because its a 'new' file being served each time).

Visual studio code CSS indentation and formatting

Go to Files menu -> Preference -> Extentions Then type CSS Formatter wait for it to load and click install

Strip HTML from Text JavaScript

Below code allows you to retain some html tags while stripping all others

function strip_tags(input, allowed) {

  allowed = (((allowed || '') + '')
    .toLowerCase()
    .match(/<[a-z][a-z0-9]*>/g) || [])
    .join(''); // making sure the allowed arg is a string containing only tags in lowercase (<a><b><c>)

  var tags = /<\/?([a-z][a-z0-9]*)\b[^>]*>/gi,
      commentsAndPhpTags = /<!--[\s\S]*?-->|<\?(?:php)?[\s\S]*?\?>/gi;

  return input.replace(commentsAndPhpTags, '')
      .replace(tags, function($0, $1) {
          return allowed.indexOf('<' + $1.toLowerCase() + '>') > -1 ? $0 : '';
      });
}

Remove items from one list in another

list1.RemoveAll(l => list2.Contains(l));

create table with sequence.nextval in oracle

You can use Oracle's SQL Developer tool to do that (My Oracle DB version is 11). While creating a table choose Advanced option and click on the Identity Column tab at the bottom and from there choose Column Sequence. This will generate a AUTO_INCREMENT column (Corresponding Trigger and Squence) for you.

What is the difference between Linear search and Binary search?

Linear Search looks through items until it finds the searched value.

Efficiency: O(n)

Example Python Code:

test_list = [1, 3, 9, 11, 15, 19, 29]
test_val1 = 25
test_val2 = 15

def linear_search(input_array, search_value):
    index = 0
    while (index < len(input_array)) and (input_array[index] < search_value):
        index += 1
    if index >= len(input_array) or input_array[index] != search_value:
        return -1

    return index


print linear_search(test_list, test_val1)
print linear_search(test_list, test_val2)

Binary Search finds the middle element of the array. Checks that middle value is greater or lower than the search value. If it is smaller, it gets the left side of the array and finds the middle element of that part. If it is greater, gets the right part of the array. It loops the operation until it finds the searched value. Or if there is no value in the array finishes the search.

Efficiency: O(logn)

Example Python Code:

test_list = [1, 3, 9, 11, 15, 19, 29]
test_val1 = 25
test_val2 = 15

def binary_search(input_array, value):
    low = 0
    high = len(input_array) - 1
    while low <= high:
        mid = (low + high) / 2
        if input_array[mid] == value:
            return mid
        elif input_array[mid] < value:
            low = mid + 1
        else:
            high = mid - 1

    return -1


print binary_search(test_list, test_val1)
print binary_search(test_list, test_val2)

Also you can see visualized information about Linear and Binary Search here: https://www.cs.usfca.edu/~galles/visualization/Search.html

Are there any HTTP/HTTPS interception tools like Fiddler for mac OS X?

HTTPScoop is awesome for inspecting the web traffic on your Mac. It's been incredibly helpful for me. I didn't think twice about the $15 price tag. There is a 14 day trial.

load and execute order of scripts

If you aren't dynamically loading scripts or marking them as defer or async, then scripts are loaded in the order encountered in the page. It doesn't matter whether it's an external script or an inline script - they are executed in the order they are encountered in the page. Inline scripts that come after external scripts are held until all external scripts that came before them have loaded and run.

Async scripts (regardless of how they are specified as async) load and run in an unpredictable order. The browser loads them in parallel and it is free to run them in whatever order it wants.

There is no predictable order among multiple async things. If one needed a predictable order, then it would have to be coded in by registering for load notifications from the async scripts and manually sequencing javascript calls when the appropriate things are loaded.

When a script tag is inserted dynamically, how the execution order behaves will depend upon the browser. You can see how Firefox behaves in this reference article. In a nutshell, the newer versions of Firefox default a dynamically added script tag to async unless the script tag has been set otherwise.

A script tag with async may be run as soon as it is loaded. In fact, the browser may pause the parser from whatever else it was doing and run that script. So, it really can run at almost any time. If the script was cached, it might run almost immediately. If the script takes awhile to load, it might run after the parser is done. The one thing to remember with async is that it can run anytime and that time is not predictable.

A script tag with defer waits until the entire parser is done and then runs all scripts marked with defer in the order they were encountered. This allows you to mark several scripts that depend upon one another as defer. They will all get postponed until after the document parser is done, but they will execute in the order they were encountered preserving their dependencies. I think of defer like the scripts are dropped into a queue that will be processed after the parser is done. Technically, the browser may be downloading the scripts in the background at any time, but they won't execute or block the parser until after the parser is done parsing the page and parsing and running any inline scripts that are not marked defer or async.

Here's a quote from that article:

script-inserted scripts execute asynchronously in IE and WebKit, but synchronously in Opera and pre-4.0 Firefox.

The relevant part of the HTML5 spec (for newer compliant browsers) is here. There is a lot written in there about async behavior. Obviously, this spec doesn't apply to older browsers (or mal-conforming browsers) whose behavior you would probably have to test to determine.

A quote from the HTML5 spec:

Then, the first of the following options that describes the situation must be followed:

If the element has a src attribute, and the element has a defer attribute, and the element has been flagged as "parser-inserted", and the element does not have an async attribute The element must be added to the end of the list of scripts that will execute when the document has finished parsing associated with the Document of the parser that created the element.

The task that the networking task source places on the task queue once the fetching algorithm has completed must set the element's "ready to be parser-executed" flag. The parser will handle executing the script.

If the element has a src attribute, and the element has been flagged as "parser-inserted", and the element does not have an async attribute The element is the pending parsing-blocking script of the Document of the parser that created the element. (There can only be one such script per Document at a time.)

The task that the networking task source places on the task queue once the fetching algorithm has completed must set the element's "ready to be parser-executed" flag. The parser will handle executing the script.

If the element does not have a src attribute, and the element has been flagged as "parser-inserted", and the Document of the HTML parser or XML parser that created the script element has a style sheet that is blocking scripts The element is the pending parsing-blocking script of the Document of the parser that created the element. (There can only be one such script per Document at a time.)

Set the element's "ready to be parser-executed" flag. The parser will handle executing the script.

If the element has a src attribute, does not have an async attribute, and does not have the "force-async" flag set The element must be added to the end of the list of scripts that will execute in order as soon as possible associated with the Document of the script element at the time the prepare a script algorithm started.

The task that the networking task source places on the task queue once the fetching algorithm has completed must run the following steps:

If the element is not now the first element in the list of scripts that will execute in order as soon as possible to which it was added above, then mark the element as ready but abort these steps without executing the script yet.

Execution: Execute the script block corresponding to the first script element in this list of scripts that will execute in order as soon as possible.

Remove the first element from this list of scripts that will execute in order as soon as possible.

If this list of scripts that will execute in order as soon as possible is still not empty and the first entry has already been marked as ready, then jump back to the step labeled execution.

If the element has a src attribute The element must be added to the set of scripts that will execute as soon as possible of the Document of the script element at the time the prepare a script algorithm started.

The task that the networking task source places on the task queue once the fetching algorithm has completed must execute the script block and then remove the element from the set of scripts that will execute as soon as possible.

Otherwise The user agent must immediately execute the script block, even if other scripts are already executing.


What about Javascript module scripts, type="module"?

Javascript now has support for module loading with syntax like this:

<script type="module">
  import {addTextToBody} from './utils.mjs';

  addTextToBody('Modules are pretty cool.');
</script>

Or, with src attribute:

<script type="module" src="http://somedomain.com/somescript.mjs">
</script>

All scripts with type="module" are automatically given the defer attribute. This downloads them in parallel (if not inline) with other loading of the page and then runs them in order, but after the parser is done.

Module scripts can also be given the async attribute which will run inline module scripts as soon as possible, not waiting until the parser is done and not waiting to run the async script in any particular order relative to other scripts.

There's a pretty useful timeline chart that shows fetch and execution of different combinations of scripts, including module scripts here in this article: Javascript Module Loading.

Disable Button in Angular 2

Change ng-disabled="!contractTypeValid" to [disabled]="!contractTypeValid"

Java POI : How to read Excel cell value and not the formula computing it?

For formula cells, excel stores two things. One is the Formula itself, the other is the "cached" value (the last value that the forumla was evaluated as)

If you want to get the last cached value (which may no longer be correct, but as long as Excel saved the file and you haven't changed it it should be), you'll want something like:

 for(Cell cell : row) {
     if(cell.getCellType() == Cell.CELL_TYPE_FORMULA) {
        System.out.println("Formula is " + cell.getCellFormula());
        switch(cell.getCachedFormulaResultType()) {
            case Cell.CELL_TYPE_NUMERIC:
                System.out.println("Last evaluated as: " + cell.getNumericCellValue());
                break;
            case Cell.CELL_TYPE_STRING:
                System.out.println("Last evaluated as \"" + cell.getRichStringCellValue() + "\"");
                break;
        }
     }
 }

Numpy ValueError: setting an array element with a sequence. This message may appear without the existing of a sequence?

You're getting the error message

ValueError: setting an array element with a sequence.

because you're trying to set an array element with a sequence. I'm not trying to be cute, there -- the error message is trying to tell you exactly what the problem is. Don't think of it as a cryptic error, it's simply a phrase. What line is giving the problem?

kOUT[i]=func(TempLake[i],Z)

This line tries to set the ith element of kOUT to whatever func(TempLAke[i], Z) returns. Looking at the i=0 case:

In [39]: kOUT[0]
Out[39]: 0.0

In [40]: func(TempLake[0], Z)
Out[40]: array([ 0.,  0.,  0.,  0.])

You're trying to load a 4-element array into kOUT[0] which only has a float. Hence, you're trying to set an array element (the left hand side, kOUT[i]) with a sequence (the right hand side, func(TempLake[i], Z)).

Probably func isn't doing what you want, but I'm not sure what you really wanted it to do (and don't forget you can usually use vectorized operations like A*B rather than looping in numpy.) That should explain the problem, anyway.

How do I run a class in a WAR from the command line?

If you're using Maven, just follow the maven-war-plugin documentation about "How do I create a JAR containing the classes in my webapp?": add <attachClasses>true</attachClasses> to the <configuration> of the plugin:

<project>
  ...
  <artifactId>mywebapp</artifactId>
  <version>1.0-SNAPSHOT</version>
  ...
  <build>
    <plugins>
      <plugin>
    <artifactId>maven-war-plugin</artifactId>
    <version>2.6</version>
    <configuration>
      <attachClasses>true</attachClasses>
    </configuration>
      </plugin>
    </plugins>
  </build>
  ...
</project>

The you will have 2 products in the target/ folder:

  • The project.war itself
  • The project-classes.jar which contains all the compiled classes in a jar

Then you will be able to execute a main class using classic method: java -cp target/project-classes.jar 'com.mycompany.MainClass' param1 param2

curl: (35) SSL connect error

If you are using curl versions curl-7.19.7-46.el6.x86_64 or older. Please provide an option as -k1 (small K1).

NullPointerException: Attempt to invoke virtual method 'int java.util.ArrayList.size()' on a null object reference

This issue is due to ArrayList variable not being instantiated. Need to declare "recordings" variable like following, that should solve the issue;

ArrayList<String> recordings = new ArrayList<String>();

this calls default constructor and assigns empty string to the recordings variable so that it is not null anymore.

NGinx Default public www location?

You can simply map nginx's root folder to the location of your website:

nano /etc/nginx/sites-enabled/default

inside the default file, look for the root in the server tag and change your website's default folder, e.g. my websites are at /var/www

server {
        listen 80 default_server;
        listen [::]:80 default_server ipv6only=on;

        root /var/www; <-- Here!
...

When I was evaluating nginx, apache2 and lighttpd, I mapped all of them to my website sitting at /var/www. I found this the best way to evaluate efficiently.

Then you can start/stop the server of your choice and see which performs best.

e.g.

service apache2 stop
service nginx start

Btw, nginx actually is very fast!

Iterating over a numpy array

I see that no good desciption for using numpy.nditer() is here. So, I am gonna go with one. According to NumPy v1.21 dev0 manual, The iterator object nditer, introduced in NumPy 1.6, provides many flexible ways to visit all the elements of one or more arrays in a systematic fashion.

I have to calculate mean_squared_error and I have already calculate y_predicted and I have y_actual from the boston dataset, available with sklearn.

def cal_mse(y_actual, y_predicted):
    """ this function will return mean squared error
       args:
           y_actual (ndarray): np array containing target variable
           y_predicted (ndarray): np array containing predictions from DecisionTreeRegressor
       returns:
           mse (integer)
    """
    sq_error = 0
    for i in np.nditer(np.arange(y_pred.shape[0])):
        sq_error += (y_actual[i] - y_predicted[i])**2
    mse = 1/y_actual.shape[0] * sq_error
    
    return mse

Hope this helps :). for further explaination visit

Maven Installation OSX Error Unsupported major.minor version 51.0

I solved it putting a old version of maven (2.x), using brew:

brew uninstall maven
brew tap homebrew/versions 
brew install maven2

How to run a PowerShell script

If your script is named with the .ps1 extension and you're in a PowerShell window, you just run ./myscript.ps1 (assuming the file is in your working directory).

This is true for me anyway on Windows 10 with PowerShell version 5.1 anyway, and I don't think I've done anything to make it possible.

What are type hints in Python 3.5?

Type hints are for maintainability and don't get interpreted by Python. In the code below, the line def add(self, ic:int) doesn't result in an error until the next return... line:

class C1:
    def __init__(self):
        self.idn = 1
    def add(self, ic: int):
        return self.idn + ic

c1 = C1()
c1.add(2)

c1.add(c1)
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "<input>", line 5, in add
TypeError: unsupported operand type(s) for +: 'int' and 'C1'

Axios get in url works but with second parameter as object it doesn't

On client:

  axios.get('/api', {
      params: {
        foo: 'bar'
      }
    });

On server:

function get(req, res, next) {

  let param = req.query.foo
   .....
}

Java: Why is the Date constructor deprecated, and what do I use instead?

Date itself is not deprecated. It's just a lot of its methods are. See here for details.

Use java.util.Calendar instead.

Unfamiliar symbol in algorithm: what does ? mean?

In math, ? means FOR ALL.

Unicode character (\u2200, ?).

SQL Network Interfaces, error: 50 - Local Database Runtime error occurred. Cannot create an automatic instance

I have solved above problem Applying below steps

enter image description here

And after you made thses changes, do following changes in your web.config

 <add name="DefaultConnection" connectionString="Data Source=(LocalDb)\v12.0;AttachDbFilename=|DataDirectory|\aspnet-Real-Time-Commenting-20170927122714.mdf;Initial Catalog=aspnet-Real-Time-Commenting-20170927122714;Integrated Security=true" providerName="System.Data.SqlClient" />

Read values into a shell variable from a pipe

I wanted something similar - a function that parses a string that can be passed as a parameter or piped.

I came up with a solution as below (works as #!/bin/sh and as #!/bin/bash)

#!/bin/sh

set -eu

my_func() {
    local content=""
    
    # if the first param is an empty string or is not set
    if [ -z ${1+x} ]; then
 
        # read content from a pipe if passed or from a user input if not passed
        while read line; do content="${content}$line"; done < /dev/stdin

    # first param was set (it may be an empty string)
    else
        content="$1"
    fi

    echo "Content: '$content'"; 
}


printf "0. $(my_func "")\n"
printf "1. $(my_func "one")\n"
printf "2. $(echo "two" | my_func)\n"
printf "3. $(my_func)\n"
printf "End\n"

Outputs:

0. Content: ''
1. Content: 'one'
2. Content: 'two'
typed text
3. Content: 'typed text'
End

For the last case (3.) you need to type, hit enter and CTRL+D to end the input.

Open soft keyboard programmatically

Please follow the below code. I am sure your problem will be solved.

if (imm != null){
        imm.toggleSoftInput(InputMethodManager.SHOW_FORCED,0);
   } 

How to see which flags -march=native will activate?

It should be (-### is similar to -v):

echo | gcc -### -E - -march=native 

To show the "real" native flags for gcc.

You can make them appear more "clearly" with a command:

gcc -### -E - -march=native 2>&1 | sed -r '/cc1/!d;s/(")|(^.* - )//g'

and you can get rid of flags with -mno-* with:

gcc -### -E - -march=native 2>&1 | sed -r '/cc1/!d;s/(")|(^.* - )|( -mno-[^\ ]+)//g'

How to change line width in IntelliJ (from 120 character)

It may be useful to notice that very good answers given above may not be enough. It is because of one more tick is required here:

enter image description here

How to give ASP.NET access to a private key in a certificate in the certificate store?

In Certificates Panel, right click some certificate -> All tasks -> Manage private key -> Add IIS_IUSRS User with full control

In my case, I didnt't need to install my certificate with "Allow private key to be exported" option checked, like said in other answers.

What is the best way to prevent session hijacking?

Have you considered reading a book on PHP security? Highly recommended.

I have had much success with the following method for non SSL certified sites.

  1. Dis-allow multiple sessions under the same account, making sure you aren't checking this solely by IP address. Rather check by token generated upon login which is stored with the users session in the database, as well as IP address, HTTP_USER_AGENT and so forth

  2. Using Relation based hyperlinks Generates a link ( eg. http://example.com/secure.php?token=2349df98sdf98a9asdf8fas98df8 ) The link is appended with a x-BYTE ( preferred size ) random salted MD5 string, upon page redirection the randomly generated token corresponds to a requested page.

    • Upon reload, several checks are done.
    • Originating IP Address
    • HTTP_USER_AGENT
    • Session Token
    • you get the point.
  3. Short Life-span session authentication cookie. as posted above, a cookie containing a secure string, which is one of the direct references to the sessions validity is a good idea. Make it expire every x Minutes, reissuing that token, and re-syncing the session with the new Data. If any mis-matches in the data, either log the user out, or having them re-authenticate their session.

I am in no means an expert on the subject, I'v had a bit of experience in this particular topic, hope some of this helps anyone out there.

window.onbeforeunload and window.onunload is not working in Firefox, Safari, Opera?

I was able to get it to work in IE and FF with jQuery's:

$(window).bind('beforeunload', function(){

});

instead of: unload, onunload, or onbeforeunload

Check if AJAX response data is empty/blank/null/undefined/0

//if(data="undefined"){

This is an assignment statement, not a comparison. Also, "undefined" is a string, it's a property. Checking it is like this: if (data === undefined) (no quotes, otherwise it's a string value)

If it's not defined, you may be returning an empty string. You could try checking for a falsy value like if (!data) as well

How to sort with a lambda?

Got it.

sort(mMyClassVector.begin(), mMyClassVector.end(), 
    [](const MyClass & a, const MyClass & b) -> bool
{ 
    return a.mProperty > b.mProperty; 
});

I assumed it'd figure out that the > operator returned a bool (per documentation). But apparently it is not so.

Change text color with Javascript?

use ONLY

function init() { 
    about = document.getElementById("about");
    about.style.color = 'blue';
}

.innerHTML() sets or gets the HTML syntax describing the element's descendants., All you need is an object here.

Demo

Counting the number of option tags in a select tag in jQuery

The best form is this

$('#example option').length

If list index exists, do X

A lot of answers, not the simple one.

To check if a index 'id' exists at dictionary dict:

dic = {}
dic['name'] = "joao"
dic['age']  = "39"

if 'age' in dic

returns true if 'age' exists.

Length of a JavaScript object

_x000D_
_x000D_
   let myobject= {}
    let isempty =  !!Object.values(myobject);
    console.log(isempty);
_x000D_
_x000D_
_x000D_

round() for float in C++

It's available since C++11 in cmath (according to http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3337.pdf)

#include <cmath>
#include <iostream>

int main(int argc, char** argv) {
  std::cout << "round(0.5):\t" << round(0.5) << std::endl;
  std::cout << "round(-0.5):\t" << round(-0.5) << std::endl;
  std::cout << "round(1.4):\t" << round(1.4) << std::endl;
  std::cout << "round(-1.4):\t" << round(-1.4) << std::endl;
  std::cout << "round(1.6):\t" << round(1.6) << std::endl;
  std::cout << "round(-1.6):\t" << round(-1.6) << std::endl;
  return 0;
}

Output:

round(0.5):  1
round(-0.5): -1
round(1.4):  1
round(-1.4): -1
round(1.6):  2
round(-1.6): -2

How to list all the roles existing in Oracle database?

Got the answer :

SELECT * FROM DBA_ROLES;

Byte Array and Int conversion in Java

/*sorry this is the correct */

     public byte[] IntArrayToByteArray(int[] iarray , int sizeofintarray)
     {
       final ByteBuffer bb ;
       bb = ByteBuffer.allocate( sizeofintarray * 4);
       for(int k = 0; k < sizeofintarray ; k++)
       bb.putInt(k * 4, iar[k]);
       return bb.array();
     }

How to delete a specific file from folder using asp.net

Delete any or specific file type(for example ".bak") from a path. See demo code below -

class Program
        {
        static void Main(string[] args)
            {

            // Specify the starting folder on the command line, or in 
            TraverseTree(ConfigurationManager.AppSettings["folderPath"]);

            // Specify the starting folder on the command line, or in 
            // Visual Studio in the Project > Properties > Debug pane.
            //TraverseTree(args[0]);

            Console.WriteLine("Press any key");
            Console.ReadKey();
            }

        public static void TraverseTree(string root)
            {

            if (string.IsNullOrWhiteSpace(root))
                return;

            // Data structure to hold names of subfolders to be
            // examined for files.
            Stack<string> dirs = new Stack<string>(20);

            if (!System.IO.Directory.Exists(root))
                {
                return;
                }

            dirs.Push(root);

            while (dirs.Count > 0)
                {
                string currentDir = dirs.Pop();
                string[] subDirs;
                try
                    {
                    subDirs = System.IO.Directory.GetDirectories(currentDir);
                    }

                // An UnauthorizedAccessException exception will be thrown if we do not have
                // discovery permission on a folder or file. It may or may not be acceptable 
                // to ignore the exception and continue enumerating the remaining files and 
                // folders. It is also possible (but unlikely) that a DirectoryNotFound exception 
                // will be raised. This will happen if currentDir has been deleted by
                // another application or thread after our call to Directory.Exists. The 
                // choice of which exceptions to catch depends entirely on the specific task 
                // you are intending to perform and also on how much you know with certainty 
                // about the systems on which this code will run.
                catch (UnauthorizedAccessException e)
                    {
                    Console.WriteLine(e.Message);
                    continue;
                    }
                catch (System.IO.DirectoryNotFoundException e)
                    {
                    Console.WriteLine(e.Message);
                    continue;
                    }

                IEnumerable<FileInfo> files = null;
                try
                    {
                    //get only .bak file
                    var directory = new DirectoryInfo(currentDir);
                    DateTime date = DateTime.Now.AddDays(-15);
                    files = directory.GetFiles("*.bak").Where(file => file.CreationTime <= date);
                    }
                catch (UnauthorizedAccessException e)
                    {
                    Console.WriteLine(e.Message);
                    continue;
                    }
                catch (System.IO.DirectoryNotFoundException e)
                    {
                    Console.WriteLine(e.Message);
                    continue;
                    }

                // Perform the required action on each file here.
                // Modify this block to perform your required task.
                foreach (FileInfo file in files)
                    {
                    try
                        {
                        // Perform whatever action is required in your scenario.
                        file.Delete();
                        Console.WriteLine("{0}: {1}, {2} was successfully deleted.", file.Name, file.Length, file.CreationTime);
                        }
                    catch (System.IO.FileNotFoundException e)
                        {
                        // If file was deleted by a separate application
                        //  or thread since the call to TraverseTree()
                        // then just continue.
                        Console.WriteLine(e.Message);
                        continue;
                        }
                    }

                // Push the subdirectories onto the stack for traversal.
                // This could also be done before handing the files.
                foreach (string str in subDirs)
                    dirs.Push(str);
                }
            }
        }

for more reference - https://msdn.microsoft.com/en-us/library/bb513869.aspx

Python read in string from file and split it into values

Something like this - for each line read into string variable a:

>>> a = "123,456"
>>> b = a.split(",")
>>> b
['123', '456']
>>> c = [int(e) for e in b]
>>> c
[123, 456]
>>> x, y = c
>>> x
123
>>> y
456

Now you can do what is necessary with x and y as assigned, which are integers.

How do I get a YouTube video thumbnail from the YouTube API?

Use img.youtube.com/vi/YouTubeID/ImageFormat.jpg

Here image formats are different like default, hqdefault, maxresdefault.

Reference — What does this symbol mean in PHP?

An overview of operators in PHP:


Logical Operators:

  • $a && $b : TRUE if both $a and $b are TRUE.
  • $a || $b : TRUE if either $a or $b is TRUE.
  • $a xor $b : TRUE if either $a or $b is TRUE, but not both.
  • ! $a : TRUE if $a is not TRUE.
  • $a and $b : TRUE if both $a and $b are TRUE.
  • $a or $b : TRUE if either $a or $b is TRUE.

Comparison operators:

  • $a == $b : TRUE if $a is equal to $b after type juggling.
  • $a === $b : TRUE if $a is equal to $b, and they are of the same type.
  • $a != $b : TRUE if $a is not equal to $b after type juggling.
  • $a <> $b : TRUE if $a is not equal to $b after type juggling.
  • $a !== $b : TRUE if $a is not equal to $b, or they are not of the same type.
  • $a < $b : TRUE if $a is strictly less than $b.
  • $a > $b : TRUE if $a is strictly greater than $b.
  • $a <= $b : TRUE if $a is less than or equal to $b.
  • $a >= $b : TRUE if $a is greater than or equal to $b.
  • $a <=> $b : An integer less than, equal to, or greater than zero when $a is respectively less than, equal to, or greater than $b. Available as of PHP 7.
  • $a ? $b : $c : if $a return $b else return $c (ternary operator)
  • $a ?? $c : Same as $a ? $a : $c (null coalescing operator - requires PHP>=7)

Arithmetic Operators:

  • -$a : Opposite of $a.
  • $a + $b : Sum of $a and $b.
  • $a - $b : Difference of $a and $b.
  • $a * $b : Product of $a and $b.
  • $a / $b : Quotient of $a and $b.
  • $a % $b : Remainder of $a divided by $b.
  • $a ** $b : Result of raising $a to the $b'th power (introduced in PHP 5.6)

Incrementing/Decrementing Operators:

  • ++$a : Increments $a by one, then returns $a.
  • $a++ : Returns $a, then increments $a by one.
  • --$a : Decrements $a by one, then returns $a.
  • $a-- : Returns $a, then decrements $a by one.

Bitwise Operators:

  • $a & $b : Bits that are set in both $a and $b are set.
  • $a | $b : Bits that are set in either $a or $b are set.
  • $a ^ $b : Bits that are set in $a or $b but not both are set.
  • ~ $a : Bits that are set in $a are not set, and vice versa.
  • $a << $b : Shift the bits of $a $b steps to the left (each step means "multiply by two")
  • $a >> $b : Shift the bits of $a $b steps to the right (each step means "divide by two")

String Operators:

  • $a . $b : Concatenation of $a and $b.

Array Operators:

  • $a + $b : Union of $a and $b.
  • $a == $b : TRUE if $a and $b have the same key/value pairs.
  • $a === $b : TRUE if $a and $b have the same key/value pairs in the same order and of the same types.
  • $a != $b : TRUE if $a is not equal to $b.
  • $a <> $b : TRUE if $a is not equal to $b.
  • $a !== $b : TRUE if $a is not identical to $b.

Assignment Operators:

  • $a = $b : The value of $b is assigned to $a
  • $a += $b : Same as $a = $a + $b
  • $a -= $b : Same as $a = $a - $b
  • *$a = $b : Same as $a = $a * $b
  • $a /= $b : Same as $a = $a / $b
  • $a %= $b : Same as $a = $a % $b
  • **$a = $b : Same as $a = $a ** $b
  • $a .= $b : Same as $a = $a . $b
  • $a &= $b : Same as $a = $a & $b
  • $a |= $b : Same as $a = $a | $b
  • $a ^= $b : Same as $a = $a ^ $b
  • $a <<= $b : Same as $a = $a << $b
  • $a >>= $b : Same as $a = $a >> $b
  • $a ??= $b : The value of $b is assigned to $a if $a is null or not defined (null coalescing assignment operator - requires PHP>=7.4)

Note

and operator and or operator have lower precedence than assignment operator =.

This means that $a = true and false; is equivalent to ($a = true) and false.

In most cases you will probably want to use && and ||, which behave in a way known from languages like C, Java or JavaScript.

Converting xml to string using C#

As Chris suggests, you can do it like this:

public string GetXMLAsString(XmlDocument myxml)
{
    return myxml.OuterXml;
}

Or like this:

public string GetXMLAsString(XmlDocument myxml)
    {

        StringWriter sw = new StringWriter();
        XmlTextWriter tx = new XmlTextWriter(sw);
        myxml.WriteTo(tx);

        string str = sw.ToString();// 
        return str;
    }

and if you really want to create a new XmlDocument then do this

XmlDocument newxmlDoc= myxml

How can I remove jenkins completely from linux

First - stop Jenkins service:

sudo service jenkins stop

Next - delete:

sudo apt-get remove --purge jenkins

If you used separate server for Jenkins, some GCP or AWS - just delete this server. Here is a video how to uninstall Jenkins from GCP Compute Engine https://youtu.be/D2HUFAc_Trw

Convenient C++ struct initialisation

I know this question is old, but there is a way to solve this until C++20 finally brings this feature from C to C++. What you can do to solve this is use preprocessor macros with static_asserts to check your initialization is valid. (I know macros are generally bad, but here I don't see another way.) See example code below:

#define INVALID_STRUCT_ERROR "Instantiation of struct failed: Type, order or number of attributes is wrong."

#define CREATE_STRUCT_1(type, identifier, m_1, p_1) \
{ p_1 };\
static_assert(offsetof(type, m_1) == 0, INVALID_STRUCT_ERROR);\

#define CREATE_STRUCT_2(type, identifier, m_1, p_1, m_2, p_2) \
{ p_1, p_2 };\
static_assert(offsetof(type, m_1) == 0, INVALID_STRUCT_ERROR);\
static_assert(offsetof(type, m_2) >= sizeof(identifier.m_1), INVALID_STRUCT_ERROR);\

#define CREATE_STRUCT_3(type, identifier, m_1, p_1, m_2, p_2, m_3, p_3) \
{ p_1, p_2, p_3 };\
static_assert(offsetof(type, m_1) == 0, INVALID_STRUCT_ERROR);\
static_assert(offsetof(type, m_2) >= sizeof(identifier.m_1), INVALID_STRUCT_ERROR);\
static_assert(offsetof(type, m_3) >= (offsetof(type, m_2) + sizeof(identifier.m_2)), INVALID_STRUCT_ERROR);\

#define CREATE_STRUCT_4(type, identifier, m_1, p_1, m_2, p_2, m_3, p_3, m_4, p_4) \
{ p_1, p_2, p_3, p_4 };\
static_assert(offsetof(type, m_1) == 0, INVALID_STRUCT_ERROR);\
static_assert(offsetof(type, m_2) >= sizeof(identifier.m_1), INVALID_STRUCT_ERROR);\
static_assert(offsetof(type, m_3) >= (offsetof(type, m_2) + sizeof(identifier.m_2)), INVALID_STRUCT_ERROR);\
static_assert(offsetof(type, m_4) >= (offsetof(type, m_3) + sizeof(identifier.m_3)), INVALID_STRUCT_ERROR);\

// Create more macros for structs with more attributes...

Then when you have a struct with const attributes, you can do this:

struct MyStruct
{
    const int attr1;
    const float attr2;
    const double attr3;
};

const MyStruct test = CREATE_STRUCT_3(MyStruct, test, attr1, 1, attr2, 2.f, attr3, 3.);

It's a bit inconvenient, because you need macros for every possible number of attributes and you need to repeat the type and name of your instance in the macro call. Also you cannot use the macro in a return statement, because the asserts come after the initialization.

But it does solve your problem: When you change the struct, the call will fail at compile-time.

If you use C++17, you can even make these macros more strict by forcing the same types, e.g.:

#define CREATE_STRUCT_3(type, identifier, m_1, p_1, m_2, p_2, m_3, p_3) \
{ p_1, p_2, p_3 };\
static_assert(offsetof(type, m_1) == 0, INVALID_STRUCT_ERROR);\
static_assert(offsetof(type, m_2) >= sizeof(identifier.m_1), INVALID_STRUCT_ERROR);\
static_assert(offsetof(type, m_3) >= (offsetof(type, m_2) + sizeof(identifier.m_2)), INVALID_STRUCT_ERROR);\
static_assert(typeid(p_1) == typeid(identifier.m_1), INVALID_STRUCT_ERROR);\
static_assert(typeid(p_2) == typeid(identifier.m_2), INVALID_STRUCT_ERROR);\
static_assert(typeid(p_3) == typeid(identifier.m_3), INVALID_STRUCT_ERROR);\

Print text in Oracle SQL Developer SQL Worksheet window

You could put your text in a select statement such as...

SELECT 'Querying Table1' FROM dual;

How can I get the current class of a div with jQuery?

<div  id="my_id" class="my_class"></div>

if that is the first div then address it like so:

document.write("div CSS class: " + document.getElementsByTagName('div')[0].className);

alternatively do this:

document.write("alternative way: " + document.getElementById('my_id').className);

It yields the following results:

div CSS class: my_class
alternative way: my_class

Python equivalent of a given wget command

Let me Improve a example with threads in case you want download many files.

import math
import random
import threading

import requests
from clint.textui import progress

# You must define a proxy list
# I suggests https://free-proxy-list.net/
proxies = {
    0: {'http': 'http://34.208.47.183:80'},
    1: {'http': 'http://40.69.191.149:3128'},
    2: {'http': 'http://104.154.205.214:1080'},
    3: {'http': 'http://52.11.190.64:3128'}
}


# you must define the list for files do you want download
videos = [
    "https://i.stack.imgur.com/g2BHi.jpg",
    "https://i.stack.imgur.com/NURaP.jpg"
]

downloaderses = list()


def downloaders(video, selected_proxy):
    print("Downloading file named {} by proxy {}...".format(video, selected_proxy))
    r = requests.get(video, stream=True, proxies=selected_proxy)
    nombre_video = video.split("/")[3]
    with open(nombre_video, 'wb') as f:
        total_length = int(r.headers.get('content-length'))
        for chunk in progress.bar(r.iter_content(chunk_size=1024), expected_size=(total_length / 1024) + 1):
            if chunk:
                f.write(chunk)
                f.flush()


for video in videos:
    selected_proxy = proxies[math.floor(random.random() * len(proxies))]
    t = threading.Thread(target=downloaders, args=(video, selected_proxy))
    downloaderses.append(t)

for _downloaders in downloaderses:
    _downloaders.start()

Microsoft Visual C++ Compiler for Python 3.4

For the different python versions:

Visual C++ |CPython
--------------------
14.0       |3.5
10.0       |3.3, 3.4
9.0        |2.6, 2.7, 3.0, 3.1, 3.2

Source: Windows Compilers for py

Also refer: this answer

Centering a background image, using CSS

I use this code, it works nice

html, body {
  height: 100%;
  width: 100%;
  padding: 0;
  margin: 0;
  background: black url(back2.png) center center no-repeat;;
-webkit-background-size: cover;
-moz-background-size: cover;
-o-background-size: cover;
background-size: cover;
}

How to find all the dependencies of a table in sql server

There is builtin procedure to check dependents:
For an example ,

Execute sp_depends @objname=N'ssc.RegDash_RoutingAct'

image

The system cannot find the file specified. in Visual Studio

Oh my days!!

Feel so embarrassed but it is my first day on the C++.

I was getting the error because of two things.

  1. I opened an empty project

  2. I didn't add #include "stdafx.h"

It ran successfully on the win 32 console.

How to get current class name including package name in Java?

There is a class, Class, that can do this:

Class c = Class.forName("MyClass"); // if you want to specify a class
Class c = this.getClass();          // if you want to use the current class

System.out.println("Package: "+c.getPackage()+"\nClass: "+c.getSimpleName()+"\nFull Identifier: "+c.getName());

If c represented the class MyClass in the package mypackage, the above code would print:

Package: mypackage
Class: MyClass
Full Identifier: mypackage.MyClass

You can take this information and modify it for whatever you need, or go check the API for more information.

regex match any whitespace

The reason I used a + instead of a '*' is because a plus is defined as one or more of the preceding element, where an asterisk is zero or more. In this case we want a delimiter that's a little more concrete, so "one or more" spaces.

word[Aa]\s+word[Bb]\s+word[Cc]

will match:

wordA wordB     wordC
worda wordb wordc
wordA   wordb   wordC

The words, in this expression, will have to be specific, and also in order (a, b, then c)