Programs & Examples On #Clientform

Argument of type 'X' is not assignable to parameter of type 'X'

This problem basically comes when your compiler gets failed to understand the difference between cast operator of the type string to Number.

you can use the Number object and pass your value to get the appropriate results for it by using Number(<<<<...Variable_Name......>>>>)

How to format a date using ng-model?

I've created a simple directive to enable standard input[type="date"] form elements to work correctly with AngularJS ~1.2.16.

Look here: https://github.com/betsol/angular-input-date

And here's the demo: http://jsfiddle.net/F2LcY/1/

Inconsistent Accessibility: Parameter type is less accessible than method

parameter type 'support.ACTInterface' is less accessible than method    
'support.clients.clients(support.ACTInterface)' 

The error says 'support.ACTInterface' is less accessible because you have made the interface as private, at least make it internal or make it public.

How do I filter ForeignKey choices in a Django ModelForm?

ForeignKey is represented by django.forms.ModelChoiceField, which is a ChoiceField whose choices are a model QuerySet. See the reference for ModelChoiceField.

So, provide a QuerySet to the field's queryset attribute. Depends on how your form is built. If you build an explicit form, you'll have fields named directly.

form.rate.queryset = Rate.objects.filter(company_id=the_company.id)

If you take the default ModelForm object, form.fields["rate"].queryset = ...

This is done explicitly in the view. No hacking around.

Subset a dataframe by multiple factor levels

Here's another:

data[data$Code == "A" | data$Code == "B", ]

It's also worth mentioning that the subsetting factor doesn't have to be part of the data frame if it matches the data frame rows in length and order. In this case we made our data frame from this factor anyway. So,

data[Code == "A" | Code == "B", ]

also works, which is one of the really useful things about R.

Python script header

From the manpage for env (GNU coreutils 6.10):

env - run a program in a modified environment

In theory you could use env to reset the environment (removing many of the existing environment variables) or add additional environment variables in the script header. Practically speaking, the two versions you mentioned are identical. (Though others have mentioned a good point: specifying python through env lets you abstractly specify python without knowing its path.)

How to print last two columns using awk

You can make use of variable NF which is set to the total number of fields in the input record:

awk '{print $(NF-1),"\t",$NF}' file

this assumes that you have at least 2 fields.

Can't get Python to import from a different folder

I believe you need to create a file called __init__.py in the Models directory so that python treats it as a module.

Then you can do:

from Models.user import User

You can include code in the __init__.py (for instance initialization code that a few different classes need) or leave it blank. But it must be there.

Programmatically change the height and width of a UIImageView Xcode Swift

Hey i figured it out shortly after. For some reason I was just having a brain fart.

image.frame = CGRectMake(0 , 0, self.view.frame.width, self.view.frame.height * 0.2)

Is there something like Codecademy for Java

Check out CodingBat! It really helped me learn java way back when (although it used to be JavaBat back then). It's a lot like Codecademy.

Where do I download JDBC drivers for DB2 that are compatible with JDK 1.5?

Right here: http://jt400.sourceforge.net/

This is what I use for that exact purpose.

EDIT: Usage Examples (minus exceptions):

// Driver initialization
AS400JDBCDriver driver = new com.ibm.as400.access.AS400JDBCDriver();
DriverManager.registerDriver(driver);

// JDBC Connection URL
String url = "jdbc:as400://10.10.10.10" + ";promt=false" // disable GUI prompting by jt400 library

// Get a Connection object (this is used to create statements, etc)
Connection conn = DriverManager.getConnection(url, UserString, PassString);

Hope that helps!

How do I import an existing Java keystore (.jks) file into a Java installation?

You can bulk import all aliases from one keystore to another:

keytool -importkeystore -srckeystore source.jks -destkeystore dest.jks

Generate Json schema from XML schema (XSD)

Copy your XML schema here & get the JSON schema code to the online tools which are available to generate JSON schema from XML schema.

Counter increment in Bash loop not working

This is a simple example

COUNTER=1
for i in {1..5}
do   
   echo $COUNTER;
   //echo "Welcome $i times"
   ((COUNTER++));    
done

How do I declare a 2d array in C++ using new?

I presume from your static array example that you want a rectangular array, and not a jagged one. You can use the following:

int *ary = new int[sizeX * sizeY];

Then you can access elements as:

ary[y*sizeX + x]

Don't forget to use delete[] on ary.

How can I get a list of all classes within current module in Python?

I frequently find myself writing command line utilities wherein the first argument is meant to refer to one of many different classes. For example ./something.py feature command —-arguments, where Feature is a class and command is a method on that class. Here's a base class that makes this easy.

The assumption is that this base class resides in a directory alongside all of its subclasses. You can then call ArgBaseClass(foo = bar).load_subclasses() which will return a dictionary. For example, if the directory looks like this:

  • arg_base_class.py
  • feature.py

Assuming feature.py implements class Feature(ArgBaseClass), then the above invocation of load_subclasses will return { 'feature' : <Feature object> }. The same kwargs (foo = bar) will be passed into the Feature class.

#!/usr/bin/env python3
import os, pkgutil, importlib, inspect

class ArgBaseClass():
    # Assign all keyword arguments as properties on self, and keep the kwargs for later.
    def __init__(self, **kwargs):
        self._kwargs = kwargs
        for (k, v) in kwargs.items():
            setattr(self, k, v)
        ms = inspect.getmembers(self, predicate=inspect.ismethod)
        self.methods = dict([(n, m) for (n, m) in ms if not n.startswith('_')])

    # Add the names of the methods to a parser object.
    def _parse_arguments(self, parser):
        parser.add_argument('method', choices=list(self.methods))
        return parser

    # Instantiate one of each of the subclasses of this class.
    def load_subclasses(self):
        module_dir = os.path.dirname(__file__)
        module_name = os.path.basename(os.path.normpath(module_dir))
        parent_class = self.__class__
        modules = {}
        # Load all the modules it the package:
        for (module_loader, name, ispkg) in pkgutil.iter_modules([module_dir]):
            modules[name] = importlib.import_module('.' + name, module_name)

        # Instantiate one of each class, passing the keyword arguments.
        ret = {}
        for cls in parent_class.__subclasses__():
            path = cls.__module__.split('.')
            ret[path[-1]] = cls(**self._kwargs)
        return ret

How to add comments into a Xaml file in WPF?

You cannot put comments inside UWP XAML tags. Your syntax is right.

TO DO:

<xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:System="clr-namespace:System;assembly=mscorlib"/>
<!-- Cool comment -->

NOT TO DO:

<xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    <!-- Cool comment -->
xmlns:System="clr-namespace:System;assembly=mscorlib"/>

SQL Server : error converting data type varchar to numeric

SQL Server 2012 and Later

Just use Try_Convert instead:

TRY_CONVERT takes the value passed to it and tries to convert it to the specified data_type. If the cast succeeds, TRY_CONVERT returns the value as the specified data_type; if an error occurs, null is returned. However if you request a conversion that is explicitly not permitted, then TRY_CONVERT fails with an error.

Read more about Try_Convert.

SQL Server 2008 and Earlier

The traditional way of handling this is by guarding every expression with a case statement so that no matter when it is evaluated, it will not create an error, even if it logically seems that the CASE statement should not be needed. Something like this:

SELECT
   Account_Code =
      Convert(
         bigint, -- only gives up to 18 digits, so use decimal(20, 0) if you must
         CASE
         WHEN X.Account_Code LIKE '%[^0-9]%' THEN NULL
         ELSE X.Account_Code
         END
      ),
   A.Descr
FROM dbo.Account A
WHERE
   Convert(
      bigint,
      CASE
      WHEN X.Account_Code LIKE '%[^0-9]%' THEN NULL
      ELSE X.Account_Code
      END
   ) BETWEEN 503100 AND 503205

However, I like using strategies such as this with SQL Server 2005 and up:

SELECT
   Account_Code = Convert(bigint, X.Account_Code),
   A.Descr
FROM
   dbo.Account A
   OUTER APPLY (
      SELECT A.Account_Code WHERE A.Account_Code NOT LIKE '%[^0-9]%'
   ) X
WHERE
   Convert(bigint, X.Account_Code) BETWEEN 503100 AND 503205

What this does is strategically switch the Account_Code values to NULL inside of the X table when they are not numeric. I initially used CROSS APPLY but as Mikael Eriksson so aptly pointed out, this resulted in the same error because the query parser ran into the exact same problem of optimizing away my attempt to force the expression order (predicate pushdown defeated it). By switching to OUTER APPLY it changed the actual meaning of the operation so that X.Account_Code could contain NULL values within the outer query, thus requiring proper evaluation order.

You may be interested to read Erland Sommarskog's Microsoft Connect request about this evaluation order issue. He in fact calls it a bug.

There are additional issues here but I can't address them now.

P.S. I had a brainstorm today. An alternate to the "traditional way" that I suggested is a SELECT expression with an outer reference, which also works in SQL Server 2000. (I've noticed that since learning CROSS/OUTER APPLY I've improved my query capability with older SQL Server versions, too--as I am getting more versatile with the "outer reference" capabilities of SELECT, ON, and WHERE clauses!)

SELECT
   Account_Code =
      Convert(
         bigint,
         (SELECT A.AccountCode WHERE A.Account_Code NOT LIKE '%[^0-9]%')
      ),
   A.Descr
FROM dbo.Account A
WHERE
   Convert(
      bigint,
      (SELECT A.AccountCode WHERE A.Account_Code NOT LIKE '%[^0-9]%')
   ) BETWEEN 503100 AND 503205

It's a lot shorter than the CASE statement.

Twitter Bootstrap - full width navbar

Just change the class container to container-fullwidth like this :

<div class="container-fullwidth">

expected assignment or function call: no-unused-expressions ReactJS

For me the error occured when using map. And I didn't use the return Statement inside the map.

{cart.map((cart_products,index) => {
    <span>{cart_products.id}</span>; 
})};

Above code produced error.

{cart.map((cart_products,index) => {
    return (<span>{cart_products.id}</span>); 
})};

Simply adding return solved it.

Error: Could not find or load main class in intelliJ IDE

In my case the problem seemed to be related to upgrading IntelliJ. When I did this I overwrote the files from the old IntelliJ with the files from the new IntelliJ (2017 community to 2018 community). After that all of my projects were broken. I tried everything in this thread and none of them worked. I tried upgrading gradle to the latest version (4 to 4.8) and that didn't work. The only thing that worked for me was deleting the entire IntelliJ folder and reinstalling it. All of my projects worked after that.

Uses for the '&quot;' entity in HTML

As other answers pointed out, it is most likely generated by some tool.

But if I were the original author of the file, my answer would be: Consistency.

If I am not allowed to put double quotes in my attributes, why put them in the element's content ? Why do these specs always have these exceptional cases .. If I had to write the HTML spec, I would say All double quotes need to be encoded. Done.

Today it is like In attribute values we need to encode double quotes, except when the attribute value itself is defined by single quotes. In the content of elements, double quotes can be, but are not required to be, encoded. (And I am surely forgetting some cases here).

Double quotes are a keyword of the spec, encode them. Lesser/greater than are a keyword of the spec, encode them. etc..

How can I disable the UITableView selection?

For me, the following worked fine:

tableView.allowsSelection = false

This means didSelectRowAt# simply won't work. That is to say, touching a row of the table, as such, will do absolutely nothing. (And hence, obviously, there will never be a selected-animation.)

(Note that if, on the cells, you have UIButton or any other controls, of course those controls will still work. Any controls you happen to have on the table cell, are totally unrelated to UITableView's ability to allow you to "select a row" using didSelectRowAt#.)

Another point to note is that: This doesn't work when the UITableView is in editing mode. To restrict cell selection in editing mode use the code as below:

tableView.allowsSelectionDuringEditing = false 

How to delete multiple files at once in Bash on Linux?

Use a wildcard (*) to match multiple files.

For example, the command below will delete all files with names beginning with abc.log.2012-03-.

rm -f abc.log.2012-03-*

I'd recommend running ls abc.log.2012-03-* to list the files so that you can see what you are going to delete before running the rm command.

For more details see the Bash man page on filename expansion.

How to ignore a property in class if null, using json.net

You can write: [JsonProperty("property_name",DefaultValueHandling = DefaultValueHandling.Ignore)]

It also takes care of not serializing properties with default values (not only null). It can be useful for enums for example.

Could not find method compile() for arguments Gradle

In my case I had to remove some files that were created by gradle at some point in my study to make things work. So, cleaning up after messing up and then it ran fine ...

If you experienced this issue in a git project, do git status and remove the unrevisioned files. (For me elasticsearch had a problem with plugins/analysis-icu).

Gradle Version : 5.1.1

C/C++ NaN constant (literal)?

In C, NAN is declared in <math.h>.

In C++, std::numeric_limits<double>::quiet_NaN() is declared in <limits>.

But for checking whether a value is NaN, you can't compare it with another NaN value. Instead use isnan() from <math.h> in C, or std::isnan() from <cmath> in C++.

How to return a resultset / cursor from a Oracle PL/SQL anonymous block that executes Dynamic SQL?

You can write a PL/SQL function to return that cursor (or you could put that function in a package if you have more code related to this):

CREATE OR REPLACE FUNCTION get_allitems
  RETURN SYS_REFCURSOR
AS
  my_cursor SYS_REFCURSOR;
BEGIN
  OPEN my_cursor FOR SELECT * FROM allitems;
  RETURN my_cursor;
END get_allitems;

This will return the cursor.

Make sure not to put your SELECT-String into quotes in PL/SQL when possible. Putting it in strings means that it can not be checked at compile time, and that it has to be parsed whenever you use it.


If you really need to use dynamic SQL you can put your query in single quotes:

  OPEN my_cursor FOR 'SELECT * FROM allitems';

This string has to be parsed whenever the function is called, which will usually be slower and hides errors in your query until runtime.

Make sure to use bind-variables where possible to avoid hard parses:

  OPEN my_cursor FOR 'SELECT * FROM allitems WHERE id = :id' USING my_id;

How to let PHP to create subdomain automatically for each user?

In addition to configuration changes on your WWW server to handle the new subdomain, your code would need to be making changes to your DNS records. So, unless you're running your own BIND (or similar), you'll need to figure out how to access your name server provider's configuration. If they don't offer some sort of API, this might get tricky.

Update: yes, I would check with your registrar if they're also providing the name server service (as is often the case). I've never explored this option before but I suspect most of the consumer registrars do not. I Googled for GoDaddy APIs and GoDaddy DNS APIs but wasn't able to turn anything up, so I guess the best option would be to check out the online help with your provider, and if that doesn't answer the question, get a hold of their support staff.

Check if element found in array c++

C++ has NULL as well, often the same as 0 (pointer to address 0x00000000).

Do you use NULL or 0 (zero) for pointers in C++?

So in C++ that null check would be:

 if (!foo)
    cout << "not found";

converting a base 64 string to an image and saving it

Here is an example, you can modify the method to accept a string parameter. Then just save the image object with image.Save(...).

public Image LoadImage()
{
    //data:image/gif;base64,
    //this image is a single pixel (black)
    byte[] bytes = Convert.FromBase64String("R0lGODlhAQABAIAAAAAAAAAAACH5BAAAAAAALAAAAAABAAEAAAICTAEAOw==");

    Image image;
    using (MemoryStream ms = new MemoryStream(bytes))
    {
        image = Image.FromStream(ms);
    }

    return image;
}

It is possible to get an exception A generic error occurred in GDI+. when the bytes represent a bitmap. If this is happening save the image before disposing the memory stream (while still inside the using statement).

Remove "Using default security password" on Spring Boot

On spring boot 2 with webflux you need to define a ReactiveAuthenticationManager

Streaming via RTSP or RTP in HTML5

The spirit of the question, I think, was not truly answered. No, you cannot use a video tag to play rtsp streams as of now. The other answer regarding the link to Chromium guy's "never" is a bit misleading as the linked thread / answer is not directly referring to Chrome playing rtsp via the video tag. Read the entire linked thread, especially the comments at the very bottom and links to other threads.

The real answer is this: No, you cannot just put a video tag on an html 5 page and play rtsp. You need to use a Javascript library of some sort (unless you want to get into playing things with flash and silverlight players) to play streaming video. {IMHO} At the rate the html 5 video discussion and implementation is going, the various vendors of proprietary video standards are not interested in helping this move forward so don't count of the promised ease of use of the video tag unless the browser makers take it upon themselves to somehow solve the problem...again, not likely.{/IMHO}

error LNK2019: unresolved external symbol _WinMain@16 referenced in function ___tmainCRTStartup

Thats a linker problem.

Try to change Properties -> Linker -> System -> SubSystem (in Visual Studio).

from Windows (/SUBSYSTEM:WINDOWS) to Console (/SUBSYSTEM:CONSOLE)

This one helped me

How to add item to the beginning of List<T>?

Update: a better idea, set the "AppendDataBoundItems" property to true, then declare the "Choose item" declaratively. The databinding operation will add to the statically declared item.

<asp:DropDownList ID="ddl" runat="server" AppendDataBoundItems="true">
    <asp:ListItem Value="0" Text="Please choose..."></asp:ListItem>
</asp:DropDownList>

http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.listcontrol.appenddatabounditems.aspx

-Oisin

How to remove the last character from a string?

We can use substring. Here's the example,

public class RemoveStringChar 
{
    public static void main(String[] args) 
    {   
        String strGiven = "Java";
        System.out.println("Before removing string character - " + strGiven);
        System.out.println("After removing string character - " + removeCharacter(strGiven, 3));
    }

    public static String removeCharacter(String strRemove, int position)
    {   
        return strRemove.substring(0, position) + strRemove.substring(position + 1);    
    }
}

Using Enum values as String literals

As Benny Neugebauer mentions, you could overwrite the toString(). However instead overwriting the toString for each enum field I like more something like this:

public enum Country{
    SPAIN("España"),
    ITALY("Italia"),
    PORTUGAL("Portugal");


    private String value;

    Country(final String value) {
        this.value = value;
    }

    public String getValue() {
        return value;
    }

    @Override
    public String toString() {
        return this.getValue();
    }
}

You could also add a static method to retrieve all the fields, to print them all, etc. Simply call getValue to obtain the string associated to each Enum item

IntelliJ - Convert a Java project/module into a Maven project/module

A visual for those that benefit from it.

enter image description here

After right-clicking the project name ("test" in this example), select "Add framework support" and check the "Maven" option.

SQL Inner join 2 tables with multiple column conditions and update

UPDATE T1,T2 
INNER JOIN T1 ON  T1.Brands = T2.Brands
SET 
T1.Inci = T2.Inci
WHERE
    T1.Category= T2.Category
AND
    T1.Date = T2.Date

Failed linking file resources

Error is associated with some issue with .xml file. Manually open each xml format file to check for error. I had same issue. Had to manually open each file. There was an error in @string call.

text-align: right; not working for <label>

As stated in other answers, label is an inline element. However, you can apply display: inline-block to the label and then center with text-align.

#name_label {
    display: inline-block;
    width: 90%;
    text-align: right;
}

Why display: inline-block and not display: inline? For the same reason that you can't align label, it's inline.

Why display: inline-block and not display: block? You could use display: block, but it will be on another line. display: inline-block combines the properties of inline and block. It's inline, but you can also give it a width, height, and align it.

Adding items to an object through the .push() method

This is really easy: Example

//my object
var sendData = {field1:value1, field2:value2};

//add element
sendData['field3'] = value3;

IDENTITY_INSERT is set to OFF - How to turn it ON?

Shouldn't you be setting identity_Insert ON, inserting the records and then turning it back off?

Like this:

set ANSI_NULLS ON
set QUOTED_IDENTIFIER ON
SET IDENTITY_INSERT tbl_content ON
GO

ALTER procedure [dbo].[spInsertDeletedIntoTBLContent]
@ContentID int, 
SET IDENTITY_INSERT tbl_content ON
...insert command...
SET IDENTITY_INSERT tbl_content OFF

Angular 2 select option (dropdown) - how to get the value on change so it can be used in a function?

You need to use an Angular form directive on the select. You can do that with ngModel. For example

@Component({
  selector: 'my-app',
  template: `
    <h2>Select demo</h2>
    <select [(ngModel)]="selectedCity" (ngModelChange)="onChange($event)" >
      <option *ngFor="let c of cities" [ngValue]="c"> {{c.name}} </option>
    </select>
  `
})
class App {
  cities = [{'name': 'SF'}, {'name': 'NYC'}, {'name': 'Buffalo'}];
  selectedCity = this.cities[1];

  onChange(city) {
    alert(city.name);
  }
}

The (ngModelChange) event listener emits events when the selected value changes. This is where you can hookup your callback.

Note you will need to make sure you have imported the FormsModule into the application.

Here is a Plunker

A required class was missing while executing org.apache.maven.plugins:maven-war-plugin:2.1.1:war

Make sure your Java version matches the project's Java version requirement. This could be an another cause for such kinds of issues.

ASP.NET MVC get textbox input value

You may use jQuery:

<input type="text" name="IP" id="IP" value=""/>
@Html.ActionLink(@Resource.ButtonTitleAdd, "Add", "Configure", new { ipValue ="xxx", TypeId = "1" }, new {@class = "link"})

<script>
  $(function () {
    $('.link').click(function () {
      var ipvalue = $("#IP").val();
      this.href = this.href.replace("xxx", ipvalue);
    });
  });
</script>

Turn off enclosing <p> tags in CKEditor 3.0

I'm doing something I'm not proud of as workaround. In my Python servlet that actually saves to the database, I do:

if description.startswith('<p>') and description.endswith('</p>'):
    description = description[3:-4]

Edit and Continue: "Changes are not allowed when..."

I ran into this today - turns out that having Debug Info set to pdb-only (or none, I'd imagine) will prevent Edit and Continue from working.

Make sure your Debug Info is set to "full" first!

Project Properties > Build > Advanced > Output > Debug Info

break statement in "if else" - java

The issue is that you are trying to have multiple statements in an if without using {}. What you currently have is interpreted like:

if( choice==5 )
{
    System.out.println( ... );
}
break;
else
{
    //...
}

You really want:

if( choice==5 )
{
    System.out.println( ... );
    break;
}
else
{
    //...
}

Also, as Farce has stated, it would be better to use else if for all the conditions instead of if because if choice==1, it will still go through and check if choice==5, which would fail, and it will still go into your else block.

if( choice==1 )
    //...
else if( choice==2 )
    //...
else if( choice==3 )
    //...
else if( choice==4 )
    //...
else if( choice==5 )
{
    //...
}
else
    //...

A more elegant solution would be using a switch statement. However, break only breaks from the most inner "block" unless you use labels. So you want to label your loop and break from that if the case is 5:

LOOP:
for(;;)
{
    System.out.println("---> Your choice: ");
    choice = input.nextInt();
    switch( choice )
    {
        case 1:
            playGame();
            break;
        case 2:
            loadGame();
            break;
        case 2:
            options();
            break;
        case 4:
            credits();
            break;
        case 5:
            System.out.println("End of Game\n Thank you for playing with us!");
            break LOOP;
        default:
            System.out.println( ... );
    }
}

Instead of labeling the loop, you could also use a flag to tell the loop to stop.

bool finished = false;
while( !finished )
{
    switch( choice )
    {
        // ...
        case 5:
            System.out.println( ... )
            finished = true;
            break;
        // ...
    }
}

Get all unique values in a JavaScript array (remove duplicates)

Now using sets you can remove duplicates and convert them back to the array.

_x000D_
_x000D_
var names = ["Mike","Matt","Nancy", "Matt","Adam","Jenny","Nancy","Carl"];_x000D_
_x000D_
console.log([...new Set(names)])
_x000D_
_x000D_
_x000D_

Another solution is to use sort & filter

_x000D_
_x000D_
var names = ["Mike","Matt","Nancy", "Matt","Adam","Jenny","Nancy","Carl"];_x000D_
var namesSorted = names.sort();_x000D_
const result = namesSorted.filter((e, i) => namesSorted[i] != namesSorted[i+1]);_x000D_
console.log(result);
_x000D_
_x000D_
_x000D_

How many socket connections possible?

I achieved 1600k concurrent idle socket connections, and at the same time 57k req/s on a Linux desktop (16G RAM, I7 2600 CPU). It's a single thread http server written in C with epoll. Source code is on github, a blog here.

Edit:

I did 600k concurrent HTTP connections (client & server) on both the same computer, with JAVA/Clojure . detail info post, HN discussion: http://news.ycombinator.com/item?id=5127251

The cost of a connection(with epoll):

  • application need some RAM per connection
  • TCP buffer 2 * 4k ~ 10k, or more
  • epoll need some memory for a file descriptor, from epoll(7)

Each registered file descriptor costs roughly 90 bytes on a 32-bit kernel, and roughly 160 bytes on a 64-bit kernel.

Creating and Update Laravel Eloquent

like @JuanchoRamone posted above (thank @Juancho) it's very useful for me, but if your data is array you should modify a little like this:

public static function createOrUpdate($data, $keys) {
    $record = self::where($keys)->first();
    if (is_null($record)) {
        return self::create($data);
    } else {
        return $record->update($data);
    }
}

Remove a JSON attribute

Simple:

delete myObj.test.key1;

Where is git.exe located?

Just to add to a couple of answers already here:

On Windows, you can use the built in "where" instead of "which" (which is for Linux). So, where git will tell you the location of git assuming that it is in the system path.

If it is not in the system path, and you want a native (no downloads or installations), reasonable time command to find it, use dir /s git.exe

Jersey Exception : SEVERE: A message body reader for Java class

In my case, I'm using POJO. And I forgot configure POJOMappingFeature as true. Maycon has pointed it out in an early answer. However some guys might have trouble to configure it in web.xml correctly, here is my example.

<servlet>
    <servlet-name>Jersey Servlet</servlet-name>
    <servlet-class>com.sun.jersey.spi.spring.container.servlet.SpringServlet</servlet-class>
    <init-param>
        <param-name>com.sun.jersey.api.json.POJOMappingFeature</param-name>
        <param-value>true</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
</servlet>

SQL Server: Invalid Column Name

with refresh table or close and open sql server this work

How do I read from parameters.yml in a controller in symfony2?

In Symfony 4, you can use the ParameterBagInterface:

use Symfony\Component\DependencyInjection\ParameterBag\ParameterBagInterface;

class MessageGenerator
{
    private $params;

    public function __construct(ParameterBagInterface $params)
    {
        $this->params = $params;
    }

    public function someMethod()
    {
        $parameterValue = $this->params->get('parameter_name');
        // ...
    }
}

and in app/config/services.yaml:

parameters:
    locale: 'en'
    dir: '%kernel.project_dir%'

It works for me in both controller and form classes. More details can be found in the Symfony blog.

open read and close a file in 1 line of code

I think the most natural way for achieving this is to define a function.

def read(filename):
    f = open(filename, 'r')
    output = f.read()
    f.close()
    return output

Then you can do the following:

output = read('pagehead.section.htm')

Maven:Failed to execute goal org.apache.maven.plugins:maven-resources-plugin:2.7:resources

From official documentation

Warning: Do not filter files with binary content like images! This will most likely result in corrupt output.

If you have both text files and binary files as resources it is recommended to have two separated folders. One folder src/main/resources (default) for the resources which are not filtered and another folder src/main/resources-filtered for the resources which are filtered.

<project>
  ...
  <build>
    ...
    <resources>
      <resource>
        <directory>src/main/resources-filtered</directory>
        <filtering>true</filtering>
      </resource>
      ...
    </resources>
    ...
  </build>
  ...
</project>

Now you can put those files into src/main/resources which should not filtered and the other files into src/main/resources-filtered.

As already mentioned filtering binary files like images,pdf`s etc. could result in corrupted output. To prevent such problems you can configure file extensions which will not being filtered.

Most certainly, You have in your directory files that cannot be filtered. So you have to specify the extensions that has not be filtered.

Run a PostgreSQL .sql file using command line arguments

Of course, you will get a fatal error for authenticating, because you do not include a user name...

Try this one, it is OK for me :)

psql -U username -d myDataBase -a -f myInsertFile

If the database is remote, use the same command with host

psql -h host -U username -d myDataBase -a -f myInsertFile

WPF MVVM ComboBox SelectedItem or SelectedValue not working

I solved the problem by adding dispatcher in UserControl_Loaded event

 Dispatcher.BeginInvoke(DispatcherPriority.Loaded, new Action(() =>
 {
     combobox.SelectedIndex = 0;
 }));

How to view instagram profile picture in full-size?

replace "150x150" with 720x720 and remove /vp/ from the link.it should work.

Making heatmap from pandas DataFrame

If you don't need a plot per say, and you're simply interested in adding color to represent the values in a table format, you can use the style.background_gradient() method of the pandas data frame. This method colorizes the HTML table that is displayed when viewing pandas data frames in e.g. the JupyterLab Notebook and the result is similar to using "conditional formatting" in spreadsheet software:

import numpy as np 
import pandas as pd


index= ['aaa', 'bbb', 'ccc', 'ddd', 'eee']
cols = ['A', 'B', 'C', 'D']
df = pd.DataFrame(abs(np.random.randn(5, 4)), index=index, columns=cols)
df.style.background_gradient(cmap='Blues')

enter image description here

For detailed usage, please see the more elaborate answer I provided on the same topic previously and the styling section of the pandas documentation.

Div height 100% and expands to fit content

I'm not entirely sure that I've understood the question because this is a fairly straightforward answer, but here goes... :)

Have you tried setting the overflow property of the container to visible or auto?

#some_div {
    height:100%;
    background:black; 
    overflow: visible;
    }

Adding that should push the black container to whatever size your dynamic container requires. I prefer visible to auto because auto seems to come with scroll bars...

Using Excel OleDb to get sheet names IN SHEET ORDER

I have created the below function using the information provided in the answer from @kraeppy (https://stackoverflow.com/a/19930386/2617732). This requires the .net framework v4.5 to be used and requires a reference to System.IO.Compression. This only works for xlsx files and not for the older xls files.

    using System.IO.Compression;
    using System.Xml;
    using System.Xml.Linq;

    static IEnumerable<string> GetWorksheetNamesOrdered(string fileName)
    {
        //open the excel file
        using (FileStream data = new FileStream(fileName, FileMode.Open))
        {
            //unzip
            ZipArchive archive = new ZipArchive(data);

            //select the correct file from the archive
            ZipArchiveEntry appxmlFile = archive.Entries.SingleOrDefault(e => e.FullName == "docProps/app.xml");

            //read the xml
            XDocument xdoc = XDocument.Load(appxmlFile.Open());

            //find the titles element
            XElement titlesElement = xdoc.Descendants().Where(e => e.Name.LocalName == "TitlesOfParts").Single();

            //extract the worksheet names
            return titlesElement
                .Elements().Where(e => e.Name.LocalName == "vector").Single()
                .Elements().Where(e => e.Name.LocalName == "lpstr")
                .Select(e => e.Value);
        }
    }

Javascript use variable as object name

I think Shaz's answer for local variables is hard to understand, though it works for non-recursive functions. Here's another way that I think it's clearer (but it's still his idea, exact same behavior). It's also not accessing the local variables dynamically, just the property of the local variable.

Essentially, it's using a global variable (attached to the function object)

// Here's  a version of it that is more straight forward.
function doIt() {
    doIt.objname = {};
    var someObject = "objname";
    doIt[someObject].value = "value";    
    console.log(doIt.objname);
})();

Which is essentially the same thing as creating a global to store the variable, so you can access it as a property. Creating a global to do this is such a hack.

Here's a cleaner hack that doesn't create global variables, it uses a local variable instead.

function doIt() {
  var scope = {
     MyProp: "Hello"
  };
  var name = "MyProp";
  console.log(scope[name]);
}

See Javascript: interpret string as object reference?

How to convert array into comma separated string in javascript

You can simply use JavaScripts join() function for that. This would simply look like a.value.join(','). The output would be a string though.

Removing black dots from li and ul

There you go, this is what I used to fix your problem:

CSS CODE

nav ul { list-style-type: none; }

HTML CODE

<nav>
<ul>
<li><a href="#">Milk</a>
   <ul>
   <li><a href="#">Goat</a></li>
   <li><a href="#">Cow</a></li>
   </ul>
</li>
<li><a href="#">Eggs</a>
   <ul>
   <li><a href="#">Free-range</a></li>
   <li><a href="#">Other</a></li>
   </ul>
</li>
<li><a href="#">Cheese</a>
   <ul>
   <li><a href="#">Smelly</a></li>
   <li><a href="#">Extra smelly</a></li>
   </ul>
</li>
</ul>
</nav>

How do I decompile a .NET EXE into readable C# source code?

Reflector and the File Disassembler add-in from Denis Bauer. It actually produces source projects from assemblies, where Reflector on its own only displays the disassembled source.

ADDED: My latest favourite is JetBrains' dotPeek.

How to manage startActivityForResult on Android?

From your FirstActivity call the SecondActivity using startActivityForResult() method

For example:

int LAUNCH_SECOND_ACTIVITY = 1
Intent i = new Intent(this, SecondActivity.class);
startActivityForResult(i, LAUNCH_SECOND_ACTIVITY);

In your SecondActivity set the data which you want to return back to FirstActivity. If you don't want to return back, don't set any.

For example: In SecondActivity if you want to send back data:

Intent returnIntent = new Intent();
returnIntent.putExtra("result",result);
setResult(Activity.RESULT_OK,returnIntent);
finish();

If you don't want to return data:

Intent returnIntent = new Intent();
setResult(Activity.RESULT_CANCELED, returnIntent);
finish();

Now in your FirstActivity class write following code for the onActivityResult() method.

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if (requestCode == LAUNCH_SECOND_ACTIVITY) {
        if(resultCode == Activity.RESULT_OK){
            String result=data.getStringExtra("result");
        }
        if (resultCode == Activity.RESULT_CANCELED) {
            //Write your code if there's no result
        }
    }
}//onActivityResult

To implement passing data between two activities in much better way in Kotlin please go through this link 'A better way to pass data between Activities'

npm not working - "read ECONNRESET"

Our company firewall will stop installing node hence connect to the personal network and install, it worked for me.

Using multiple IF statements in a batch file

IF EXIST "somefile.txt" (
  IF EXIST "someotherfile.txt" (
    SET var="somefile.txt","someotherfile.txt"
  )
) ELSE (
  CALL :SUB
)
:SUB
ECHO Sorry... nothin' there.
GOTO:EOF

Is this feasible?

SETLOCAL ENABLEDELAYEDEXPANSION
IF EXIST "somefile.txt" (
  SET var="somefile.txt"
  IF EXIST "someotherfile.txt" (
    SET var=!var!,"someotherfile.txt"
  )
) ELSE (
  IF EXIST "someotherfile.txt" (
    SET var="someotherfile.txt"
  ) ELSE (
  GOTO:EOF
  )
)

How can I find the dimensions of a matrix in Python?

m = [[1, 1, 1, 0],[0, 5, 0, 1],[2, 1, 3, 10]]

print(len(m),len(m[0]))

Output

(3 4)

How to merge 2 List<T> and removing duplicate values from it in C#

Union has not good performance : this article describe about compare them with together

var dict = list2.ToDictionary(p => p.Number);
foreach (var person in list1)
{
        dict[person.Number] = person;
}
var merged = dict.Values.ToList();

Lists and LINQ merge: 4820ms
Dictionary merge: 16ms
HashSet and IEqualityComparer: 20ms
LINQ Union and IEqualityComparer: 24ms

React Native android build failed. SDK location not found

In your Project Directory there is a folder called "android" and inside it there is the local.properties file . Delete the file and the build should run successfully

SELECT with a Replace()

You are creating an alias P and later in the where clause you are using the same, that is what is creating the problem. Don't use P in where, try this instead:

SELECT Replace(Postcode, ' ', '') AS P FROM Contacts
WHERE Postcode LIKE 'NW101%'

show dbs gives "Not Authorized to execute command" error

There are two things,

1) You can run the mongodb instance without username and password first.

2) Then you can add the user to the system database of the mongodb which is default one using the query below.

db.createUser({
  user: "myUserAdmin",
  pwd: "abc123",
  roles: [ { role: "userAdminAnyDatabase", db: "admin" } ]
})

Thanks.

Print string to text file

With using pathlib module, indentation isn't needed.

import pathlib
pathlib.Path("output.txt").write_text("Purchase Amount: {}" .format(TotalAmount))

As of python 3.6, f-strings is available.

pathlib.Path("output.txt").write_text(f"Purchase Amount: {TotalAmount}")

What IDE to use for Python?

Results

Spreadsheet version

spreadsheet screenshot

Alternatively, in plain text: (also available as a a screenshot)

                         Bracket Matching -.  .- Line Numbering
                          Smart Indent -.  |  |  .- UML Editing / Viewing
         Source Control Integration -.  |  |  |  |  .- Code Folding
                    Error Markup -.  |  |  |  |  |  |  .- Code Templates
  Integrated Python Debugging -.  |  |  |  |  |  |  |  |  .- Unit Testing
    Multi-Language Support -.  |  |  |  |  |  |  |  |  |  |  .- GUI Designer (Qt, Eric, etc)
   Auto Code Completion -.  |  |  |  |  |  |  |  |  |  |  |  |  .- Integrated DB Support
     Commercial/Free -.  |  |  |  |  |  |  |  |  |  |  |  |  |  |  .- Refactoring
   Cross Platform -.  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |     
                  +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
Atom              |Y |F |Y |Y*|Y |Y |Y |Y |Y |Y |  |Y |Y |  |  |  |  |*many plugins
Editra            |Y |F |Y |Y |  |  |Y |Y |Y |Y |  |Y |  |  |  |  |  |
Emacs             |Y |F |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |  |  |  |
Eric Ide          |Y |F |Y |  |Y |Y |  |Y |  |Y |  |Y |  |Y |  |  |  |
Geany             |Y |F |Y*|Y |  |  |  |Y |Y |Y |  |Y |  |  |  |  |  |*very limited
Gedit             |Y |F |Y¹|Y |  |  |  |Y |Y |Y |  |  |Y²|  |  |  |  |¹with plugin; ²sort of
Idle              |Y |F |Y |  |Y |  |  |Y |Y |  |  |  |  |  |  |  |  |
IntelliJ          |Y |CF|Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |
JEdit             |Y |F |  |Y |  |  |  |  |Y |Y |  |Y |  |  |  |  |  |
KDevelop          |Y |F |Y*|Y |  |  |Y |Y |Y |Y |  |Y |  |  |  |  |  |*no type inference
Komodo            |Y |CF|Y |Y |Y |Y |Y |Y |Y |Y |  |Y |Y |Y |  |Y |  |
NetBeans*         |Y |F |Y |Y |Y |  |Y |Y |Y |Y |Y |Y |Y |Y |  |  |Y |*pre-v7.0
Notepad++         |W |F |Y |Y |  |Y*|Y*|Y*|Y |Y |  |Y |Y*|  |  |  |  |*with plugin
Pfaide            |W |C |Y |Y |  |  |  |Y |Y |Y |  |Y |Y |  |  |  |  |
PIDA              |LW|F |Y |Y |  |  |  |Y |Y |Y |  |Y |  |  |  |  |  |VIM based
PTVS              |W |F |Y |Y |Y |Y |Y |Y |Y |Y |  |Y |  |  |Y*|  |Y |*WPF bsed
PyCharm           |Y |CF|Y |Y*|Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |*JavaScript
PyDev (Eclipse)   |Y |F |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |  |  |  |
PyScripter        |W |F |Y |  |Y |Y |  |Y |Y |Y |  |Y |Y |Y |  |  |  |
PythonWin         |W |F |Y |  |Y |  |  |Y |Y |  |  |Y |  |  |  |  |  |
SciTE             |Y |F¹|  |Y |  |Y |  |Y |Y |Y |  |Y |Y |  |  |  |  |¹Mac version is
ScriptDev         |W |C |Y |Y |Y |Y |  |Y |Y |Y |  |Y |Y |  |  |  |  |    commercial
Spyder            |Y |F |Y |  |Y |Y |  |Y |Y |Y |  |  |  |  |  |  |  |
Sublime Text      |Y |CF|Y |Y |  |Y |Y |Y |Y |Y |  |Y |Y |Y*|  |  |  |extensible w/Python,
TextMate          |M |F |  |Y |  |  |Y |Y |Y |Y |  |Y |Y |  |  |  |  |    *PythonTestRunner
UliPad            |Y |F |Y |Y |Y |  |  |Y |Y |  |  |  |Y |Y |  |  |  |
Vim               |Y |F |Y |Y |Y |Y |Y |Y |Y |Y |  |Y |Y |Y |  |  |  |
Visual Studio     |W |CF|Y |Y |Y |Y |Y |Y |Y |Y |? |Y |? |? |Y |? |Y |
Visual Studio Code|Y |F |Y |Y |Y |Y |Y |Y |Y |Y |? |Y |? |? |? |? |Y |uses plugins
WingIde           |Y |C |Y |Y*|Y |Y |Y |Y |Y |Y |  |Y |Y |Y |  |  |  |*support for C
Zeus              |W |C |  |  |  |  |Y |Y |Y |Y |  |Y |Y |  |  |  |  |
                  +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
   Cross Platform -'  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |     
     Commercial/Free -'  |  |  |  |  |  |  |  |  |  |  |  |  |  |  '- Refactoring
   Auto Code Completion -'  |  |  |  |  |  |  |  |  |  |  |  |  '- Integrated DB Support
    Multi-Language Support -'  |  |  |  |  |  |  |  |  |  |  '- GUI Designer (Qt, Eric, etc)
  Integrated Python Debugging -'  |  |  |  |  |  |  |  |  '- Unit Testing
                    Error Markup -'  |  |  |  |  |  |  '- Code Templates
         Source Control Integration -'  |  |  |  |  '- Code Folding
                          Smart Indent -'  |  |  '- UML Editing / Viewing
                         Bracket Matching -'  '- Line Numbering

Acronyms used:

 L  - Linux
 W  - Windows
 M  - Mac
 C  - Commercial
 F  - Free
 CF - Commercial with Free limited edition
 ?  - To be confirmed

I don't mention basics like syntax highlighting as I expect these by default.


This is a just dry list reflecting your feedback and comments, I am not advocating any of these tools. I will keep updating this list as you keep posting your answers.

PS. Can you help me to add features of the above editors to the list (like auto-complete, debugging, etc.)?

We have a comprehensive wiki page for this question https://wiki.python.org/moin/IntegratedDevelopmentEnvironments

Submit edits to the spreadsheet

Clang vs GCC for my Linux Development project

I use both because sometimes they give different, useful error messages.

The Python project was able to find and fix a number of small buglets when one of the core developers first tried compiling with clang.

I'm getting an error "invalid use of incomplete type 'class map'

I am just providing another case where you can get this error message. The solution will be the same as Adam has mentioned above. This is from a real code and I renamed the class name.

class FooReader {
  public:
     /** Constructor */
     FooReader() : d(new FooReaderPrivate(this)) { }  // will not compile here
     .......
  private:
     FooReaderPrivate* d;
};

====== In a separate file =====
class FooReaderPrivate {
  public:
     FooReaderPrivate(FooReader*) : parent(p) { }
  private:
     FooReader* parent;
};

The above will no pass the compiler and get error: invalid use of incomplete type FooReaderPrivate. You basically have to put the inline portion into the *.cpp implementation file. This is OK. What I am trying to say here is that you may have a design issue. Cross reference of two classes may be necessary some cases, but I would say it is better to avoid them at the start of the design. I would be wrong, but please comment then I will update my posting.

Find out who is locking a file on a network share

The sessions are handled by the NAS device. What you are asking is dependant on the NAS device and nothing to do with windows. You would have to have a look into your NAS firmware to see to what it support. The only other way is sniff the packets and work it out yourself.

"Correct" way to specifiy optional arguments in R functions

Just wanted to point out that the built-in sink function has good examples of different ways to set arguments in a function:

> sink
function (file = NULL, append = FALSE, type = c("output", "message"),
    split = FALSE)
{
    type <- match.arg(type)
    if (type == "message") {
        if (is.null(file))
            file <- stderr()
        else if (!inherits(file, "connection") || !isOpen(file))
            stop("'file' must be NULL or an already open connection")
        if (split)
            stop("cannot split the message connection")
        .Internal(sink(file, FALSE, TRUE, FALSE))
    }
    else {
        closeOnExit <- FALSE
        if (is.null(file))
            file <- -1L
        else if (is.character(file)) {
            file <- file(file, ifelse(append, "a", "w"))
            closeOnExit <- TRUE
        }
        else if (!inherits(file, "connection"))
            stop("'file' must be NULL, a connection or a character string")
        .Internal(sink(file, closeOnExit, FALSE, split))
    }
}

Remove all html tags from php string

<?php $data = "<div><p>Welcome to my PHP class, we are glad you are here</p></div>"; echo strip_tags($data); ?>

Or if you have a content coming from the database;

<?php $data = strip_tags($get_row['description']); ?> <?=substr($data, 0, 100) ?><?php if(strlen($data) > 100) { ?>...<?php } ?>

selecting from multi-index pandas

One way is to use the get_level_values Index method:

In [11]: df
Out[11]:
     0
A B
1 4  1
2 5  2
3 6  3

In [12]: df.iloc[df.index.get_level_values('A') == 1]
Out[12]:
     0
A B
1 4  1

In 0.13 you'll be able to use xs with drop_level argument:

df.xs(1, level='A', drop_level=False) # axis=1 if columns

Note: if this were column MultiIndex rather than index, you could use the same technique:

In [21]: df1 = df.T

In [22]: df1.iloc[:, df1.columns.get_level_values('A') == 1]
Out[22]:
A  1
B  4
0  1

How do I save and restore multiple variables in python?

The following approach seems simple and can be used with variables of different size:

import hickle as hkl
# write variables to filename [a,b,c can be of any size]
hkl.dump([a,b,c], filename)

# load variables from filename
a,b,c = hkl.load(filename)

Escaping HTML strings with jQuery

You can easily do it with vanilla js.

Simply add a text node the document. It will be escaped by the browser.

var escaped = document.createTextNode("<HTML TO/ESCAPE/>")
document.getElementById("[PARENT_NODE]").appendChild(escaped)

Get MIME type from filename extension

FileExtension handle the file extension and not the Mime. The user can change the file extension, so check the Mime. The codes examples associate Mime by file extension, this is wrong and does not work.

Need to get the contenttype file and check if the table Mime contetType this file according to the file extension. Now, how to get the ContentType of the file?

Using FileUpload is thus: FileUpload.PostedFile.ContentType; Now if I already have the file, as caught your ContentType?

Meaning of numbers in "col-md-4"," col-xs-1", "col-lg-2" in Bootstrap

The Bootstrap grid system has four classes:
xs (for phones)
sm (for tablets)
md (for desktops)
lg (for larger desktops)

The classes above can be combined to create more dynamic and flexible layouts.

Tip: Each class scales up, so if you wish to set the same widths for xs and sm, you only need to specify xs.

OK, the answer is easy, but read on:

col-lg- stands for column large = 1200px
col-md- stands for column medium = 992px
col-xs- stands for column extra small = 768px

The pixel numbers are the breakpoints, so for example col-xs is targeting the element when the window is smaller than 768px(likely mobile devices)...

I also created the image below to show how the grid system works, in this examples I use them with 3, like col-lg-6 to show you how the grid system work in the page, look at how lg, md and xs are responsive to the window size:

Bootstrap grid system, col-*-6

How to programmatically open the Permission Screen for a specific app on Android Marshmallow?

It is not possible to programmatically open the permission screen. Instead, we can open the app settings screen.

Code

Intent i = new Intent(android.provider.Settings.ACTION_APPLICATION_DETAILS_SETTINGS, Uri.parse("package:" + BuildConfig.APPLICATION_ID));
startActivity(i);

Sample Output

enter image description here

How to get the android Path string to a file on Assets folder?

AFAIK the files in the assets directory don't get unpacked. Instead, they are read directly from the APK (ZIP) file.

So, you really can't make stuff that expects a file accept an asset 'file'.

Instead, you'll have to extract the asset and write it to a seperate file, like Dumitru suggests:

  File f = new File(getCacheDir()+"/m1.map");
  if (!f.exists()) try {

    InputStream is = getAssets().open("m1.map");
    int size = is.available();
    byte[] buffer = new byte[size];
    is.read(buffer);
    is.close();


    FileOutputStream fos = new FileOutputStream(f);
    fos.write(buffer);
    fos.close();
  } catch (Exception e) { throw new RuntimeException(e); }

  mapView.setMapFile(f.getPath());

Newline in JLabel

You can try and do this:

myLabel.setText("<html>" + myString.replaceAll("<","&lt;").replaceAll(">", "&gt;").replaceAll("\n", "<br/>") + "</html>")

The advantages of doing this are:

  • It replaces all newlines with <br/>, without fail.
  • It automatically replaces eventual < and > with &lt; and &gt; respectively, preventing some render havoc.

What it does is:

  • "<html>" + adds an opening html tag at the beginning
  • .replaceAll("<", "&lt;").replaceAll(">", "&gt;") escapes < and > for convenience
  • .replaceAll("\n", "<br/>") replaces all newlines by br (HTML line break) tags for what you wanted
  • ... and + "</html>" closes our html tag at the end.

P.S.: I'm very sorry to wake up such an old post, but whatever, you have a reliable snippet for your Java!

Xcode 6: Keyboard does not show up in simulator

This seems to be a bug in iOS 8. There are two fixes to this problem :

  1. Toggle between simulator keyboard and MacBook keyboard using the Command+K shortcut.

  2. Reattach keyboard to simulator :

    a. Open Simulator

    b. Select Hardware -> Keyboard

    c. Uncheck and then check 'Connect Hardware Keyboard'

Screenshot for step 2

OR simply press the Shift + Command + K shortcut

How to import a Python class that is in a directory above?

from ..subpkg2 import mod

Per the Python docs: When inside a package hierarchy, use two dots, as the import statement doc says:

When specifying what module to import you do not have to specify the absolute name of the module. When a module or package is contained within another package it is possible to make a relative import within the same top package without having to mention the package name. By using leading dots in the specified module or package after from you can specify how high to traverse up the current package hierarchy without specifying exact names. One leading dot means the current package where the module making the import exists. Two dots means up one package level. Three dots is up two levels, etc. So if you execute from . import mod from a module in the pkg package then you will end up importing pkg.mod. If you execute from ..subpkg2 import mod from within pkg.subpkg1 you will import pkg.subpkg2.mod. The specification for relative imports is contained within PEP 328.

PEP 328 deals with absolute/relative imports.

PHP convert date format dd/mm/yyyy => yyyy-mm-dd

Do this:

date('Y-m-d', strtotime('dd/mm/yyyy'));

But make sure 'dd/mm/yyyy' is the actual date.

Call to undefined function App\Http\Controllers\ [ function name ]

say you define the static getFactorial function inside a CodeController

then this is the way you need to call a static function, because static properties and methods exists with in the class, not in the objects created using the class.

CodeController::getFactorial($index);

----------------UPDATE----------------

To best practice I think you can put this kind of functions inside a separate file so you can maintain with more easily.

to do that

create a folder inside app directory and name it as lib (you can put a name you like).

this folder to needs to be autoload to do that add app/lib to composer.json as below. and run the composer dumpautoload command.

"autoload": {
    "classmap": [
                "app/commands",
                "app/controllers",
                ............
                "app/lib"
    ]
},

then files inside lib will autoloaded.

then create a file inside lib, i name it helperFunctions.php

inside that define the function.

if ( ! function_exists('getFactorial'))
{

    /**
     * return the factorial of a number
     *
     * @param $number
     * @return string
     */
    function getFactorial($date)
    {
        $fact = 1;

        for($i = 1; $i <= $num ;$i++)
            $fact = $fact * $i;

        return $fact;

     }
}

and call it anywhere within the app as

$fatorial_value = getFactorial(225);

Possible to make labels appear when hovering over a point in matplotlib?

This solution works when hovering a line without the need to click it:

import matplotlib.pyplot as plt

# Need to create as global variable so our callback(on_plot_hover) can access
fig = plt.figure()
plot = fig.add_subplot(111)

# create some curves
for i in range(4):
    # Giving unique ids to each data member
    plot.plot(
        [i*1,i*2,i*3,i*4],
        gid=i)

def on_plot_hover(event):
    # Iterating over each data member plotted
    for curve in plot.get_lines():
        # Searching which data member corresponds to current mouse position
        if curve.contains(event)[0]:
            print "over %s" % curve.get_gid()

fig.canvas.mpl_connect('motion_notify_event', on_plot_hover)           
plt.show()

What is the equivalent of "none" in django templates?

You can also use the built-in template filter default:

If value evaluates to False (e.g. None, an empty string, 0, False); the default "--" is displayed.

{{ profile.user.first_name|default:"--" }}

Documentation: https://docs.djangoproject.com/en/dev/ref/templates/builtins/#default

Difference between long and int data types

The guarantees the standard gives you go like this:

1 == sizeof(char) <= sizeof(short) <= sizeof (int) <= sizeof(long) <= sizeof(long long)

So it's perfectly valid for sizeof (int) and sizeof (long) to be equal, and many platforms choose to go with this approach. You will find some platforms where int is 32 bits, long is 64 bits, and long long is 128 bits, but it seems very common for sizeof (long) to be 4.

(Note that long long is recognized in C from C99 onwards, but was normally implemented as an extension in C++ prior to C++11.)

Delete forked repo from GitHub

select project to delete->settings->buttom click delete button->enter name of the repositories

Date formatting in WPF datagrid

Binding="{Binding YourColumn ,StringFormat='yyyy-MM-dd'}"

Archive the artifacts in Jenkins

In Jenkins 2.60.3 there is a way to delete build artifacts (not the archived artifacts) in order to save hard drive space on the build machine. In the General section, check "Discard old builds" with strategy "Log Rotation" and then go into its Advanced options. Two more options will appear related to keeping build artifacts for the job based on number of days or builds.

The settings that work for me are to enter 1 for "Max # of builds to keep with artifacts" and then to have a post-build action to archive the artifacts. This way, all artifacts from all builds will be archived, all information from builds will be saved, but only the last build will keep its own artifacts.

Discard old builds options

Cannot add a project to a Tomcat server in Eclipse

In my case, the .project file was read-only (it was pulled from the source code control system that way). Making it writable resolved the issue.

Eclipse v4.7 (Oxygen).

How is a non-breaking space represented in a JavaScript string?

The jQuery docs for text() says

Due to variations in the HTML parsers in different browsers, the text returned may vary in newlines and other white space.

I'd use $td.html() instead.

How to implement a Navbar Dropdown Hover in Bootstrap v4?

Hoverable dropdown without losing functionality of popper.js for bootstrap 4 only

Javascript

$('.dropdown-hoverable').hover(function(){
    $(this).children('[data-toggle="dropdown"]').click();
}, function(){
    $(this).children('[data-toggle="dropdown"]').click();
});

HTML

<nav class="nav">
  <li class="nav-item dropdown dropdown-hoverable">
    <a class="nav-link dropdown-toggle" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" href="#">Menu link</a>
    <ul class="dropdown-menu">
    </ul>
  </li>
</nav>

Format price in the current locale and currency

I think Google could have answered your question ;-) See http://blog.chapagain.com.np/magento-format-price/.

You can do it with

$formattedPrice = Mage::helper('core')->currency($finalPrice, true, false);

Add a CSS border on hover without moving the element

Add a border to the regular item, the same color as the background, so that it cannot be seen. That way the item has a border: 1px whether it is being hovered or not.

What is the difference between dynamic and static polymorphism in Java?

Polymorphism: Polymorphism is the ability of an object to take on many forms. The most common use of polymorphism in OOP occurs when a parent class reference is used to refer to a child class object.

Dynamic Binding/Runtime Polymorphism :

Run time Polymorphism also known as method overriding. In this Mechanism by which a call to an overridden function is resolved at a Run-Time.

public class DynamicBindingTest {

    public static void main(String args[]) {
        Vehicle vehicle = new Car(); //here Type is vehicle but object will be Car
        vehicle.start();       //Car's start called because start() is overridden method
    }
}

class Vehicle {

    public void start() {
        System.out.println("Inside start method of Vehicle");
    }
}

class Car extends Vehicle {

    @Override
    public void start() {
        System.out.println("Inside start method of Car");
    }
}

Output:

Inside start method of Car

Static Binding /compile-time polymorphism:

Which method is to be called is decided at compile-time only.

public class StaticBindingTest {

    public static void main(String args[])  {
       Collection c = new HashSet();
       StaticBindingTest et = new StaticBindingTest();
       et.sort(c);

    }

    //overloaded method takes Collection argument
    public Collection sort(Collection c){
        System.out.println("Inside Collection sort method");
        return c;
    }


   //another overloaded method which takes HashSet argument which is sub class
    public Collection sort(HashSet hs){
        System.out.println("Inside HashSet sort method");
        return hs;
    }

}

Output: Inside Collection sort metho

Send POST request with JSON data using Volley

protected Map<String, String> getParams() {
   Map<String, String> params = new HashMap<String, String>();

   JSONObject JObj = new JSONObject();

   try {
           JObj.put("Id","1");
           JObj.put("Name", "abc");

   } catch (Exception e) {
       e.printStackTrace();
   }

   params.put("params", JObj.toString());
   // Map.Entry<String,String>
   Log.d("Parameter", params.toString());
   return params;
}

Make element fixed on scroll

I wouldn't bother with jQuery or LESS. A javascript framework is overkill in my opinion.

window.addEventListener('scroll', function (evt) {

  // This value is your scroll distance from the top
  var distance_from_top = document.body.scrollTop;

  // The user has scrolled to the tippy top of the page. Set appropriate style.
  if (distance_from_top === 0) {

  }

  // The user has scrolled down the page.
  if(distance_from_top > 0) {

  }

});

How to get out of while loop in java with Scanner method "hasNext" as condition?

If you don't want to use an EOF character for this, you can use StringTokenizer :

import java.util.*;
public class Test{
   public static void main(){
      Scanner sc = new Scanner (System.in);
      System.out.print("Enter your sentence: ");
      String s=sc.nextLine();
      StringTokenizer st=new StringTokenizer(s," ");//" " is the delimiter here.
      while (st.hasMoreTokens() ) {
        String s1 = st.nextToken();
        System.out.println(s1);
      }

      System.out.println("The loop has been ended");
   }
}

Negation in Python

Python prefers English keywords to punctuation. Use not x, i.e. not os.path.exists(...). The same thing goes for && and || which are and and or in Python.

Export to CSV using MVC, C# and jQuery

What happens if you get rid of the stringwriter:

        Response.Clear();
        Response.AddHeader("Content-Disposition", "attachment; filename=adressenbestand.csv");
        Response.ContentType = "text/csv";
        //write the header
        Response.Write(String.Format("{0},{1},{2},{3}", CMSMessages.EmailAddress, CMSMessages.Gender, CMSMessages.FirstName, CMSMessages.LastName));

        //write every subscriber to the file
        var resourceManager = new ResourceManager(typeof(CMSMessages));
        foreach (var record in filterRecords.Select(x => x.First().Subscriber))
        {
            Response.Write(String.Format("{0},{1},{2},{3}", record.EmailAddress, record.Gender.HasValue ? resourceManager.GetString(record.Gender.ToString()) : "", record.FirstName, record.LastName));
        }

        Response.End();

IPC performance: Named Pipe vs Socket

One problem with sockets is that they do not have a way to flush the buffer. There is something called the Nagle algorithm which collects all data and flushes it after 40ms. So if it is responsiveness and not bandwidth you might be better off with a pipe.

You can disable the Nagle with the socket option TCP_NODELAY but then the reading end will never receive two short messages in one single read call.

So test it, i ended up with none of this and implemented memory mapped based queues with pthread mutex and semaphore in shared memory, avoiding a lot of kernel system calls (but today they aren't very slow anymore).

Setting up PostgreSQL ODBC on Windows

As I see PostgreSQL installer doesn't include 64 bit version of ODBC driver, which is necessary in your case. Download psqlodbc_09_00_0310-x64.zip and install it instead. I checked that on Win 7 64 bit and PostgreSQL 9.0.4 64 bit and it looks ok:

enter image description here

Test connection:

enter image description here

jQuery Force set src attribute for iframe

Setting src attribute didn't work for me. The iframe didn't display the url.

What worked for me was:

window.open(url, "nameof_iframe");

Hope it helps someone.

How to find largest objects in a SQL Server database?

This query help to find largest table in you are connection.

SELECT  TOP 1 OBJECT_NAME(OBJECT_ID) TableName, st.row_count
FROM sys.dm_db_partition_stats st
WHERE index_id < 2
ORDER BY st.row_count DESC

Declaring abstract method in TypeScript

I use to throw an exception in the base class.

protected abstractMethod() {
    throw new Error("abstractMethod not implemented");
}

Then you have to implement in the sub-class. The cons is that there is no build error, but run-time. The pros is that you can call this method from the super class, assuming that it will work :)

HTH!

Milton

Submit form without reloading page

You can't do this using forms the normal way. Instead, you want to use AJAX.

A sample function that will submit the data and alert the page response.

function submitForm() {
    var http = new XMLHttpRequest();
    http.open("POST", "<<whereverTheFormIsGoing>>", true);
    http.setRequestHeader("Content-type","application/x-www-form-urlencoded");
    var params = "search=" + <<get search value>>; // probably use document.getElementById(...).value
    http.send(params);
    http.onload = function() {
        alert(http.responseText);
    }
}

How are people unit testing with Entity Framework 6, should you bother?

I would not unit test code I don't own. What are you testing here, that the MSFT compiler works?

That said, to make this code testable, you almost HAVE to make your data access layer separate from your business logic code. What I do is take all of my EF stuff and put it in a (or multiple) DAO or DAL class which also has a corresponding interface. Then I write my service which will have the DAO or DAL object injected in as a dependency (constructor injection preferably) referenced as the interface. Now the part that needs to be tested (your code) can easily be tested by mocking out the DAO interface and injecting that into your service instance inside your unit test.

//this is testable just inject a mock of IProductDAO during unit testing
public class ProductService : IProductService
{
    private IProductDAO _productDAO;

    public ProductService(IProductDAO productDAO)
    {
        _productDAO = productDAO;
    }

    public List<Product> GetAllProducts()
    {
        return _productDAO.GetAll();
    }

    ...
}

I would consider live Data Access Layers to be part of integration testing, not unit testing. I have seen guys run verifications on how many trips to the database hibernate makes before, but they were on a project that involved billions of records in their datastore and those extra trips really mattered.

Java string to date conversion

My humble test program. I use it to play around with the formatter and look-up long dates that I find in log-files (but who has put them there...).

My test program:

package be.test.package.time;

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.TimeZone;

public class TimeWork {

    public static void main(String[] args) {    

        TimeZone timezone = TimeZone.getTimeZone("UTC");

        List<Long> longs = new ArrayList<>();
        List<String> strings = new ArrayList<>();

        //Formatting a date needs a timezone - otherwise the date get formatted to your system time zone.
        //Use 24h format HH. In 12h format hh can be in range 0-11, which makes 12 overflow to 0.
        DateFormat formatter = new SimpleDateFormat("dd-MM-yyyy HH:mm:ss.SSS");
        formatter.setTimeZone(timezone);

        Date now = new Date();

        //Test dates
        strings.add(formatter.format(now));
        strings.add("01-01-1970 00:00:00.000");
        strings.add("01-01-1970 00:00:01.000");
        strings.add("01-01-1970 00:01:00.000");
        strings.add("01-01-1970 01:00:00.000");
        strings.add("01-01-1970 10:00:00.000");
        strings.add("01-01-1970 12:00:00.000");
        strings.add("01-01-1970 24:00:00.000");
        strings.add("02-01-1970 00:00:00.000");
        strings.add("01-01-1971 00:00:00.000");
        strings.add("01-01-2014 00:00:00.000");
        strings.add("31-12-1969 23:59:59.000");
        strings.add("31-12-1969 23:59:00.000");
        strings.add("31-12-1969 23:00:00.000");

        //Test data
        longs.add(now.getTime());
        longs.add(-1L);
        longs.add(0L); //Long date presentation at - midnight 1/1/1970 UTC - The timezone is important!
        longs.add(1L);
        longs.add(1000L);
        longs.add(60000L);
        longs.add(3600000L);
        longs.add(36000000L);
        longs.add(43200000L);
        longs.add(86400000L);
        longs.add(31536000000L);
        longs.add(1388534400000L);
        longs.add(7260000L);
        longs.add(1417706084037L);
        longs.add(-7260000L);

        System.out.println("===== String to long =====");

        //Show the long value of the date
        for (String string: strings) {
            try {
                Date date = formatter.parse(string);
                System.out.println("Formated date : " + string + " = Long = " + date.getTime());
            } catch (ParseException e) {
                e.printStackTrace();
            }
        }

        System.out.println("===== Long to String =====");

        //Show the date behind the long
        for (Long lo : longs) {
            Date date = new Date(lo);
            String string = formatter.format(date);
            System.out.println("Formated date : " + string + " = Long = " + lo);        
        }
    }
}

Test results:

===== String to long =====
Formated date : 05-12-2014 10:17:34.873 = Long = 1417774654873
Formated date : 01-01-1970 00:00:00.000 = Long = 0
Formated date : 01-01-1970 00:00:01.000 = Long = 1000
Formated date : 01-01-1970 00:01:00.000 = Long = 60000
Formated date : 01-01-1970 01:00:00.000 = Long = 3600000
Formated date : 01-01-1970 10:00:00.000 = Long = 36000000
Formated date : 01-01-1970 12:00:00.000 = Long = 43200000
Formated date : 01-01-1970 24:00:00.000 = Long = 86400000
Formated date : 02-01-1970 00:00:00.000 = Long = 86400000
Formated date : 01-01-1971 00:00:00.000 = Long = 31536000000
Formated date : 01-01-2014 00:00:00.000 = Long = 1388534400000
Formated date : 31-12-1969 23:59:59.000 = Long = -1000
Formated date : 31-12-1969 23:59:00.000 = Long = -60000
Formated date : 31-12-1969 23:00:00.000 = Long = -3600000
===== Long to String =====
Formated date : 05-12-2014 10:17:34.873 = Long = 1417774654873
Formated date : 31-12-1969 23:59:59.999 = Long = -1
Formated date : 01-01-1970 00:00:00.000 = Long = 0
Formated date : 01-01-1970 00:00:00.001 = Long = 1
Formated date : 01-01-1970 00:00:01.000 = Long = 1000
Formated date : 01-01-1970 00:01:00.000 = Long = 60000
Formated date : 01-01-1970 01:00:00.000 = Long = 3600000
Formated date : 01-01-1970 10:00:00.000 = Long = 36000000
Formated date : 01-01-1970 12:00:00.000 = Long = 43200000
Formated date : 02-01-1970 00:00:00.000 = Long = 86400000
Formated date : 01-01-1971 00:00:00.000 = Long = 31536000000
Formated date : 01-01-2014 00:00:00.000 = Long = 1388534400000
Formated date : 01-01-1970 02:01:00.000 = Long = 7260000
Formated date : 04-12-2014 15:14:44.037 = Long = 1417706084037
Formated date : 31-12-1969 21:59:00.000 = Long = -7260000

How to do a deep comparison between 2 objects with lodash?

I need to know if they have difference in one of their nested properties

Other answers provide potentially satisfactory solutions to this problem, but it is sufficiently difficult and common that it looks like there's a very popular package to help solve this issue deep-object-diff.

To use this package you'd need to npm i deep-object-diff then:

const { diff } = require('deep-object-diff');
var a = {};
var b = {};

a.prop1 = 2;
a.prop2 = { prop3: 2 };

b.prop1 = 2;
b.prop2 = { prop3: 3 };

if (!_.isEqual(a, b)) {
  const abDiff = diff(a, b);
  console.log(abDiff);
  /*
  {
    prop2: {
      prop3: 3
    }
  }
  */
}

// or alternatively
const abDiff = diff(a, b);
if(!_.isEmpty(abDiff)) {
  // if a diff exists then they aren't deeply equal
  // perform needed actions with diff...
}

Here's a more detailed case with property deletions directly from their docs:

const lhs = {
  foo: {
    bar: {
      a: ['a', 'b'],
      b: 2,
      c: ['x', 'y'],
      e: 100 // deleted
    }
  },
  buzz: 'world'
};

const rhs = {
  foo: {
    bar: {
      a: ['a'], // index 1 ('b')  deleted
      b: 2, // unchanged
      c: ['x', 'y', 'z'], // 'z' added
      d: 'Hello, world!' // added
    }
  },
  buzz: 'fizz' // updated
};

console.log(diff(lhs, rhs)); // =>
/*
{
  foo: {
    bar: {
      a: {
        '1': undefined
      },
      c: {
        '2': 'z'
      },
      d: 'Hello, world!',
      e: undefined
    }
  },
  buzz: 'fizz'
}
*/

For implementation details and other usage info, refer to that repo.

How can I clear an HTML file input with JavaScript?

Here are my two cents, the input files are stored as array so here is how to null it

document.getElementById('selector').value = []

this return an empty array and works on all browsers

Get key and value of object in JavaScript?

$.each(top_brands, function() {
  var key = Object.keys(this)[0];
  var value = this[key];
  brand_options.append($("<option />").val(key).text(key + " "  + value));
});

Attach to a processes output for viewing

For me, this worked:

  1. Login as the owner of the process (even root is denied permission)

    ~$ su - process_owner
    
  2. Tail the file descriptor as mentioned in many other answers.

    ~$ tail -f /proc/<process-id>/fd/1 # (0: stdin, 1: stdout, 2: stderr)
    

How to change to an older version of Node.js

the easiest way i have found is to just use the nodejs.org site:

  1. go to https://nodejs.org/en/download/releases/
  2. find version you want and click download
  3. on mac click the .pkg executable and follow the installation instructions (not sure what the correct executable is for windows)
  4. be happy now that you are on the version of node you wanted

Send JSON data via POST (ajax) and receive json response from Controller (MVC)

You don't need to call $.toJSON and add traditional = true

data: { sendInfo: array },
traditional: true

would do.

How to hide a status bar in iOS?

It's working for me ,

Add below code into the info.plist file ,

 <key>UIStatusBarHidden</key>
 <false/>
 <key>UIViewControllerBasedStatusBarAppearance</key>
 <false/>

Hopes this is work for some one .

1030 Got error 28 from storage engine

Drop the problem database, then reboot mysql service (sudo service mysql restart, for example).

What are the true benefits of ExpandoObject?

One advantage is for binding scenarios. Data grids and property grids will pick up the dynamic properties via the TypeDescriptor system. In addition, WPF data binding will understand dynamic properties, so WPF controls can bind to an ExpandoObject more readily than a dictionary.

Interoperability with dynamic languages, which will be expecting DLR properties rather than dictionary entries, may also be a consideration in some scenarios.

Bootstrap 3 Carousel Not Working

For me, the carousel wasn't working in the DreamWeaver CC provided the code in the "template" page I am playing with. I needed to add the data-ride="carousel" attribute to the carousel div in order for it to start working. Thanks to Adarsh for his code snippet which highlighted the missing attribute.

How to return value from function which has Observable subscription inside?

function getValueFromObservable() {
    this.store.subscribe(
        (data:any) => {
            return data
        }
    )
}
console.log(getValueFromObservable())

In above case console.log runs before the promise is resolved so no value is displayed, change it to following

function getValueFromObservable() {
    return this.store
}

getValueFromObservable()
 .subscribe((data: any) => {
    // do something here with data
    console.log(data);
});

other solution is when you need data inside getValueFromObservable to return the observable using of operator and subscribe to the function.

 function getValueFromObservable() {
        return this.store.subscribe((data: any) => {
            // do something with data here
            console.log(data);
            //return again observable.
            return of(data);
       })
    }

    getValueFromObservable()
     .subscribe((data: any) => {
        // do something here with data
        console.log(data);
    });

Angular File Upload

Complete example of File upload using Angular and nodejs(express)

HTML Code

            <div class="form-group">
                <label for="file">Choose File</label><br/>
                <input type="file" id="file" (change)="uploadFile($event.target.files)" multiple>
            </div>

TS Component Code

uploadFile(files) {
    console.log('files', files)
        var formData = new FormData();

    for(let i =0; i < files.length; i++){
      formData.append("files", files[i], files[i]['name']);
        }

    this.httpService.httpPost('/fileUpload', formData)
      .subscribe((response) => {
        console.log('response', response)
      },
        (error) => {
      console.log('error in fileupload', error)
       })
  }

Node Js code

fileUpload API controller

function start(req, res) {
fileUploadService.fileUpload(req, res)
    .then(fileUploadServiceResponse => {
        res.status(200).send(fileUploadServiceResponse)
    })
    .catch(error => {
        res.status(400).send(error)
    })
}

module.exports.start = start

Upload service using multer

const multer = require('multer') // import library
const moment = require('moment')
const q = require('q')
const _ = require('underscore')
const fs = require('fs')
const dir = './public'

/** Store file on local folder */
let storage = multer.diskStorage({
destination: function (req, file, cb) {
    cb(null, 'public')
},
filename: function (req, file, cb) {
    let date = moment(moment.now()).format('YYYYMMDDHHMMSS')
    cb(null, date + '_' + file.originalname.replace(/-/g, '_').replace(/ /g,     '_'))
}
})

/** Upload files  */
let upload = multer({ storage: storage }).array('files')

/** Exports fileUpload function */
module.exports = {
fileUpload: function (req, res) {
    let deferred = q.defer()

    /** Create dir if not exist */
    if (!fs.existsSync(dir)) {
        fs.mkdirSync(dir)
        console.log(`\n\n ${dir} dose not exist, hence created \n\n`)
    }

    upload(req, res, function (err) {
        if (req && (_.isEmpty(req.files))) {
            deferred.resolve({ status: 200, message: 'File not attached', data: [] })
        } else {
            if (err) {
                deferred.reject({ status: 400, message: 'error', data: err })
            } else {
                deferred.resolve({
                    status: 200,
                    message: 'File attached',
                    filename: _.pluck(req.files,
                        'filename'),
                    data: req.files
                })
            }
        }
    })
    return deferred.promise
}
}

Populating a dictionary using for loops (python)

>>> dict(zip(keys, values))
{0: 'Hi', 1: 'I', 2: 'am', 3: 'John'}

How to repeat last command in python interpreter shell?

By default use ALT+p for previous command, you can change to Up-Arrow instead in IDLE GUi >> OPtions >> Configure IDLE >>Key >>Custom Key Binding It is not necesary to run a custom script, besides readlines module doesnt run in Windows. Hope That Help. :)

How to remove a variable from a PHP session array

Currently you are clearing the name array, you need to call the array then the index you want to unset within the array:

$ar[0]==2
$ar[1]==7
$ar[2]==9

unset ($ar[2])

Two ways of unsetting values within an array:

<?php
# remove by key:
function array_remove_key ()
{
  $args  = func_get_args();
  return array_diff_key($args[0],array_flip(array_slice($args,1)));
}
# remove by value:
function array_remove_value ()
{
  $args = func_get_args();
  return array_diff($args[0],array_slice($args,1));
}

$fruit_inventory = array(
  'apples' => 52,
  'bananas' => 78,
  'peaches' => 'out of season',
  'pears' => 'out of season',
  'oranges' => 'no longer sold',
  'carrots' => 15,
  'beets' => 15,
);

echo "<pre>Original Array:\n",
     print_r($fruit_inventory,TRUE),
     '</pre>';

# For example, beets and carrots are not fruits...
$fruit_inventory = array_remove_key($fruit_inventory,
                                    "beets",
                                    "carrots");
echo "<pre>Array after key removal:\n",
     print_r($fruit_inventory,TRUE),
     '</pre>';

# Let's also remove 'out of season' and 'no longer sold' fruit...
$fruit_inventory = array_remove_value($fruit_inventory,
                                      "out of season",
                                      "no longer sold");
echo "<pre>Array after value removal:\n",
     print_r($fruit_inventory,TRUE),
     '</pre>';
?> 

So, unset has no effect to internal array counter!!!

http://us.php.net/unset

HashMap(key: String, value: ArrayList) returns an Object instead of ArrayList?

I suppose your dictMap is of type HashMap, which makes it default to HashMap<Object, Object>. If you want it to be more specific, declare it as HashMap<String, ArrayList>, or even better, as HashMap<String, ArrayList<T>>

ggplot2: sorting a plot

Here are a couple of ways.

The first will order things based on the order seen in the data frame:

x$variable <- factor(x$variable, levels=unique(as.character(x$variable)) )

The second orders the levels based on another variable (value in this case):

x <- transform(x, variable=reorder(variable, -value) ) 

How do I check if file exists in Makefile so I can delete it?

Missing a semicolon

if [ -a myApp ];
then
  rm myApp
fi

However, I assume you are checking for existence before deletion to prevent an error message. If so, you can just use rm -f myApp which "forces" delete, i.e. doesn't error out if the file didn't exist.

Creating new table with SELECT INTO in SQL

The syntax for creating a new table is

CREATE TABLE new_table
AS
SELECT *
  FROM old_table

This will create a new table named new_table with whatever columns are in old_table and copy the data over. It will not replicate the constraints on the table, it won't replicate the storage attributes, and it won't replicate any triggers defined on the table.

SELECT INTO is used in PL/SQL when you want to fetch data from a table into a local variable in your PL/SQL block.

How do I determine if my python shell is executing in 32bit or 64bit?

Basically a variant on Matthew Marshall's answer (with struct from the std.library):

import struct
print struct.calcsize("P") * 8

Nested select statement in SQL Server

You need to alias the subquery.

SELECT name FROM (SELECT name FROM agentinformation) a  

or to be more explicit

SELECT a.name FROM (SELECT name FROM agentinformation) a  

How can I programmatically freeze the top row of an Excel worksheet in Excel 2007 VBA?

To expand this question into the realm of use outside of Excel s own VBA, the ActiveWindow property must be addressed as a child of the Excel.Application object.

Example for creating an Excel workbook from Access:

Using the Excel.Application object in another Office application's VBA project will require you to add Microsoft Excel 15.0 Object library (or equivalent for your own version).

Option Explicit

Sub xls_Build__Report()
    Dim xlApp As Excel.Application, ws As Worksheet, wb As Workbook
    Dim fn As String

    Set xlApp = CreateObject("Excel.Application")
    xlApp.DisplayAlerts = False
    xlApp.Visible = True

    Set wb = xlApp.Workbooks.Add
    With wb
        .Sheets(1).Name = "Report"
        With .Sheets("Report")

            'report generation here

        End With

        'This is where the Freeze Pane is dealt with
        'Freezes top row
        With xlApp.ActiveWindow
            .SplitColumn = 0
            .SplitRow = 1
            .FreezePanes = True
        End With

        fn = CurrentProject.Path & "\Reports\Report_" & Format(Date, "yyyymmdd") & ".xlsx"
        If CBool(Len(Dir(fn, vbNormal))) Then Kill fn
        .SaveAs FileName:=fn, FileFormat:=xlOpenXMLWorkbook
    End With

Close_and_Quit:
    wb.Close False
    xlApp.Quit
End Sub

The core process is really just a reiteration of previously submitted answers but I thought it was important to demonstrate how to deal with ActiveWindow when you are not within Excel's own VBA. While the code here is VBA, it should be directly transcribable to other languages and platforms.

What are the differences between Deferred, Promise and Future in JavaScript?

  • A promise represents a value that is not yet known
  • A deferred represents work that is not yet finished

A promise is a placeholder for a result which is initially unknown while a deferred represents the computation that results in the value.

Reference

how to achieve transfer file between client and server using java socket

Reading quickly through the source it seems that you're not far off. The following link should help (I did something similar but for FTP). For a file send from server to client, you start off with a file instance and an array of bytes. You then read the File into the byte array and write the byte array to the OutputStream which corresponds with the InputStream on the client's side.

http://www.rgagnon.com/javadetails/java-0542.html

Edit: Here's a working ultra-minimalistic file sender and receiver. Make sure you understand what the code is doing on both sides.

package filesendtest;

import java.io.*;
import java.net.*;

class TCPServer {

    private final static String fileToSend = "C:\\test1.pdf";

    public static void main(String args[]) {

        while (true) {
            ServerSocket welcomeSocket = null;
            Socket connectionSocket = null;
            BufferedOutputStream outToClient = null;

            try {
                welcomeSocket = new ServerSocket(3248);
                connectionSocket = welcomeSocket.accept();
                outToClient = new BufferedOutputStream(connectionSocket.getOutputStream());
            } catch (IOException ex) {
                // Do exception handling
            }

            if (outToClient != null) {
                File myFile = new File( fileToSend );
                byte[] mybytearray = new byte[(int) myFile.length()];

                FileInputStream fis = null;

                try {
                    fis = new FileInputStream(myFile);
                } catch (FileNotFoundException ex) {
                    // Do exception handling
                }
                BufferedInputStream bis = new BufferedInputStream(fis);

                try {
                    bis.read(mybytearray, 0, mybytearray.length);
                    outToClient.write(mybytearray, 0, mybytearray.length);
                    outToClient.flush();
                    outToClient.close();
                    connectionSocket.close();

                    // File sent, exit the main method
                    return;
                } catch (IOException ex) {
                    // Do exception handling
                }
            }
        }
    }
}

package filesendtest;

import java.io.*;
import java.io.ByteArrayOutputStream;
import java.net.*;

class TCPClient {

    private final static String serverIP = "127.0.0.1";
    private final static int serverPort = 3248;
    private final static String fileOutput = "C:\\testout.pdf";

    public static void main(String args[]) {
        byte[] aByte = new byte[1];
        int bytesRead;

        Socket clientSocket = null;
        InputStream is = null;

        try {
            clientSocket = new Socket( serverIP , serverPort );
            is = clientSocket.getInputStream();
        } catch (IOException ex) {
            // Do exception handling
        }

        ByteArrayOutputStream baos = new ByteArrayOutputStream();

        if (is != null) {

            FileOutputStream fos = null;
            BufferedOutputStream bos = null;
            try {
                fos = new FileOutputStream( fileOutput );
                bos = new BufferedOutputStream(fos);
                bytesRead = is.read(aByte, 0, aByte.length);

                do {
                        baos.write(aByte);
                        bytesRead = is.read(aByte);
                } while (bytesRead != -1);

                bos.write(baos.toByteArray());
                bos.flush();
                bos.close();
                clientSocket.close();
            } catch (IOException ex) {
                // Do exception handling
            }
        }
    }
}

Related

Byte array of unknown length in java

Edit: The following could be used to fingerprint small files before and after transfer (use SHA if you feel it's necessary):

public static String md5String(File file) {
    try {
        InputStream fin = new FileInputStream(file);
        java.security.MessageDigest md5er = MessageDigest.getInstance("MD5");
        byte[] buffer = new byte[1024];
        int read;
        do {
            read = fin.read(buffer);
            if (read > 0) {
                md5er.update(buffer, 0, read);
            }
        } while (read != -1);
        fin.close();
        byte[] digest = md5er.digest();
        if (digest == null) {
            return null;
        }
        String strDigest = "0x";
        for (int i = 0; i < digest.length; i++) {
            strDigest += Integer.toString((digest[i] & 0xff)
                    + 0x100, 16).substring(1).toUpperCase();
        }
        return strDigest;
    } catch (Exception e) {
        return null;
    }
}

Numbering rows within groups in a data frame

I would like to add a data.table variant using the rank() function which provides the additional possibility to change the ordering and thus makes it a bit more flexible than the seq_len() solution and is pretty similar to row_number functions in RDBMS.

# Variant with ascending ordering
library(data.table)
dt <- data.table(df)
dt[, .( val
   , num = rank(val))
    , by = list(cat)][order(cat, num),]

    cat        val num
 1: aaa 0.05638315   1
 2: aaa 0.25767250   2
 3: aaa 0.30776611   3
 4: aaa 0.46854928   4
 5: aaa 0.55232243   5
 6: bbb 0.17026205   1
 7: bbb 0.37032054   2
 8: bbb 0.48377074   3
 9: bbb 0.54655860   4
10: bbb 0.81240262   5
11: ccc 0.28035384   1
12: ccc 0.39848790   2
13: ccc 0.62499648   3
14: ccc 0.76255108   4

# Variant with descending ordering
dt[, .( val
   , num = rank(-val))
    , by = list(cat)][order(cat, num),]

Get String in YYYYMMDD format from JS date object?

Try this:

function showdate(){

var a = new Date();
var b = a.getFullYear();
var c = a.getMonth();
(++c < 10)? c = "0" + c : c;
var d = a.getDate();
(d < 10)? d = "0" + d : d;
var final = b + "-" + c + "-" + d; 

return final;


} 

document.getElementById("todays_date").innerHTML = showdate();

Replace Default Null Values Returned From Left Outer Join

That's as easy as

IsNull(FieldName, 0)

Or more completely:

SELECT iar.Description, 
  ISNULL(iai.Quantity,0) as Quantity, 
  ISNULL(iai.Quantity * rpl.RegularPrice,0) as 'Retail', 
  iar.Compliance 
FROM InventoryAdjustmentReason iar
LEFT OUTER JOIN InventoryAdjustmentItem iai  on (iar.Id = iai.InventoryAdjustmentReasonId)
LEFT OUTER JOIN Item i on (i.Id = iai.ItemId)
LEFT OUTER JOIN ReportPriceLookup rpl on (rpl.SkuNumber = i.SkuNo)
WHERE iar.StoreUse = 'yes'

Catching FULL exception message

I found it!

Simply print out $Error[0] for the last error message.

How to set up a squid Proxy with basic username and password authentication?

Here's what I had to do to setup basic auth on Ubuntu 14.04 (didn't find a guide anywhere else)

Basic squid conf

/etc/squid3/squid.conf instead of the super bloated default config file

auth_param basic program /usr/lib/squid3/basic_ncsa_auth /etc/squid3/passwords
auth_param basic realm proxy
acl authenticated proxy_auth REQUIRED
http_access allow authenticated

# Choose the port you want. Below we set it to default 3128.
http_port 3128

Please note the basic_ncsa_auth program instead of the old ncsa_auth

squid 2.x

For squid 2.x you need to edit /etc/squid/squid.conf file and place:

auth_param basic program /usr/lib/squid/digest_pw_auth /etc/squid/passwords
auth_param basic realm proxy
acl authenticated proxy_auth REQUIRED
http_access allow authenticated

Setting up a user

sudo htpasswd -c /etc/squid3/passwords username_you_like

and enter a password twice for the chosen username then

sudo service squid3 restart

squid 2.x

sudo htpasswd -c /etc/squid/passwords username_you_like

and enter a password twice for the chosen username then

sudo service squid restart

htdigest vs htpasswd

For the many people that asked me: the 2 tools produce different file formats:

  • htdigest stores the password in plain text.
  • htpasswd stores the password hashed (various hashing algos are available)

Despite this difference in format basic_ncsa_auth will still be able to parse a password file generated with htdigest. Hence you can alternatively use:

sudo htdigest -c /etc/squid3/passwords realm_you_like username_you_like

Beware that this approach is empirical, undocumented and may not be supported by future versions of Squid.

On Ubuntu 14.04 htdigest and htpasswd are both available in the [apache2-utils][1] package.

MacOS

Similar as above applies, but file paths are different.

Install squid

brew install squid

Start squid service

brew services start squid

Squid config file is stored at /usr/local/etc/squid.conf.

Comment or remove following line:

http_access allow localnet

Then similar to linux config (but with updated paths) add this:

auth_param basic program /usr/local/Cellar/squid/4.8/libexec/basic_ncsa_auth /usr/local/etc/squid_passwords
auth_param basic realm proxy
acl authenticated proxy_auth REQUIRED
http_access allow authenticated

Note that path to basic_ncsa_auth may be different since it depends on installed version when using brew, you can verify this with ls /usr/local/Cellar/squid/. Also note that you should add the above just bellow the following section:

#
# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
#

Now generate yourself a user:password basic auth credential (note: htpasswd and htdigest are also both available on MacOS)

htpasswd -c /usr/local/etc/squid_passwords username_you_like

Restart the squid service

brew services restart squid

Check if file exists and whether it contains a specific string

test -e will test whether a file exists or not. The test command returns a zero value if the test succeeds or 1 otherwise.

Test can be written either as test -e or using []

[ -e "$file_name" ] && grep "poet" $file_name

Unless you actually need the output of grep you can test the return value as grep will return 1 if there are no matches and zero if there are any.

In general terms you can test if a string is non-empty using [ "string" ] which will return 0 if non-empty and 1 if empty

Asynchronous Function Call in PHP

I dont have a direct answer, but you might want to look into these things:

Change WPF window background image in C# code

What about this:

new ImageBrush(new BitmapImage(new Uri(BaseUriHelper.GetBaseUri(this), "Images/icon.png")))

or alternatively, this:

this.Background = new ImageBrush(new BitmapImage(new Uri(@"pack://application:,,,/myapp;component/Images/icon.png")));

iterating and filtering two lists using java 8

if you have class with id and you want to filter by id

line1 : you mape all the id

line2: filter what is not exist in the map

Set<String> mapId = entityResponse.getEntities().stream().map(Entity::getId).collect(Collectors.toSet());

List<String> entityNotExist = entityValues.stream().filter(n -> !mapId.contains(n.getId())).map(DTOEntity::getId).collect(Collectors.toList());

Generating HTML email body in C#

If you don't want a dependency on the full .NET Framework, there's also a library that makes your code look like:

string userName = "John Doe";

var mailBody = new HTML {
    new H(1) {
        "Heading Here"
    },
    new P {
        string.Format("Dear {0},", userName),
        new Br()
    },
    new P {
        "First part of the email body goes here"
    }
};

string htmlString = mailBody.Render();

It's open source, you can download it from http://sourceforge.net/projects/htmlplusplus/

Disclaimer: I'm the author of this library, it was written to solve the same issue exactly - send an HTML email from an application.

Skip certain tables with mysqldump

For sake of completeness, here is a script which actually could be a one-liner to get a backup from a database, excluding (ignoring) all the views. The db name is assumed to be employees:

ignore=$(mysql --login-path=root1 INFORMATION_SCHEMA \
    --skip-column-names --batch \
    -e "select 
          group_concat(
            concat('--ignore-table=', table_schema, '.', table_name) SEPARATOR ' '
          ) 
        from tables 
        where table_type = 'VIEW' and table_schema = 'employees'")

mysqldump --login-path=root1 --column-statistics=0 --no-data employees $ignore > "./backups/som_file.sql"   

You can update the logic of the query. In general using group_concat and concat you can generate almost any desired string or shell command.

How to create and use resources in .NET

Well, after searching around and cobbling together various points from around StackOverflow (gee, I love this place already), most of the problems were already past this stage. I did manage to work out an answer to my problem though.

How to create a resource:

In my case, I want to create an icon. It's a similar process, no matter what type of data you want to add as a resource though.

  • Right click the project you want to add a resource to. Do this in the Solution Explorer. Select the "Properties" option from the list.
  • Click the "Resources" tab.
  • The first button along the top of the bar will let you select the type of resource you want to add. It should start on string. We want to add an icon, so click on it and select "Icons" from the list of options.
  • Next, move to the second button, "Add Resource". You can either add a new resource, or if you already have an icon already made, you can add that too. Follow the prompts for whichever option you choose.
  • At this point, you can double click the newly added resource to edit it. Note, resources also show up in the Solution Explorer, and double clicking there is just as effective.

How to use a resource:

Great, so we have our new resource and we're itching to have those lovely changing icons... How do we do that? Well, lucky us, C# makes this exceedingly easy.

There is a static class called Properties.Resources that gives you access to all your resources, so my code ended up being as simple as:

paused = !paused;
if (paused)
    notifyIcon.Icon = Properties.Resources.RedIcon;
else
    notifyIcon.Icon = Properties.Resources.GreenIcon;

Done! Finished! Everything is simple when you know how, isn't it?

MINGW64 "make build" error: "bash: make: command not found"

  • Go to ezwinports, https://sourceforge.net/projects/ezwinports/files/

  • Download make-4.2.1-without-guile-w32-bin.zip (get the version without guile)

  • Extract zip
  • Copy the contents to C:\ProgramFiles\Git\mingw64\ merging the folders, but do NOT overwrite/replace any exisiting files.

Java List.add() UnsupportedOperationException

You must initialize your List seeAlso :

List<String> seeAlso = new Vector<String>();

or

List<String> seeAlso = new ArrayList<String>();

popup form using html/javascript/css

Look at easiest example to create popup using css and javascript.

  1. Create HREF link using HTML.
  2. Create a popUp by HTML and CSS
  3. Write CSS
  4. Call JavaScript mehod

See the full example at this link http://makecodeeasy.blogspot.in/2012/07/popup-in-java-script-and-css.html

Adjust list style image position?

I think what you really want to do is add the padding (you are currently adding to the <li>) to the <ul> tag and then the bullet points will move with the text of the <li>.

There is also the list-style-position you could look into. It affects how the lines wrap around the bullet images.

javascript variable reference/alias

Expanding on user187291's post, you could also use getters/setters to get around having to use functions.

var x = 1;
var ref = {
    get x()  { return x; },
    set x(v) { x = v; }
};
(ref.x)++;
console.log(x); // prints '2'
x--;
console.log(ref.x); // prints '1'

What are "named tuples" in Python?

I think it's worth adding information about NamedTuples using type hinting:

# dependencies
from typing import NamedTuple, Optional

# definition
class MyNamedTuple(NamedTuple):
    an_attribute: str
    my_attribute: Optional[str] = None
    next_attribute: int = 1

# instantiation
my_named_tuple = MyNamedTuple("abc", "def")
# or more explicitly:
other_tuple = MyNamedTuple(an_attribute="abc", my_attribute="def")

# access
assert "abc" == my_named_tuple.an_attribute
assert 1 == other_tuple.next_attribute

Getting DOM elements by classname

I prefer using Symfony for this. Their libraries are pretty nice.

Use the The DomCrawler Component

Example:

$browser = new HttpBrowser(HttpClient::create());
$crawler = $browser->request('GET', 'example.com');
$class = $crawler->filter('.class')->first();

How to remove not null constraint in sql server using query

Remove column constraint: not null to null

ALTER TABLE test ALTER COLUMN column_01 DROP NOT NULL;

Setting values of input fields with Angular 6

You should use the following:

       <td><input id="priceInput-{{orderLine.id}}" type="number" [(ngModel)]="orderLine.price"></td>

You will need to add the FormsModule to your app.module in the inputs section as follows:

import { FormsModule } from '@angular/forms';

@NgModule({
  declarations: [
    ...
  ],
  imports: [
    BrowserModule,
    FormsModule
  ],
  ..

The use of the brackets around the ngModel are as follows:

  • The [] show that it is taking an input from your TS file. This input should be a public member variable. A one way binding from TS to HTML.

  • The () show that it is taking output from your HTML file to a variable in the TS file. A one way binding from HTML to TS.

  • The [()] are both (e.g. a two way binding)

See here for more information: https://angular.io/guide/template-syntax

I would also suggest replacing id="priceInput-{{orderLine.id}}" with something like this [id]="getElementId(orderLine)" where getElementId(orderLine) returns the element Id in the TS file and can be used anywere you need to reference the element (to avoid simple bugs like calling it priceInput1 in one place and priceInput-1 in another. (if you still need to access the input by it's Id somewhere else)

How to rename array keys in PHP?

foreach ($basearr as &$row)
{
    $row['value'] = $row['url'];
    unset( $row['url'] );
}

unset($row);

What's the effect of adding 'return false' to a click event listener?

When using forms,we can use 'return false' to prevent submitting.

function checkForm() {
    // return true to submit, return false to prevent submitting
}
<form onsubmit="return checkForm()">
    ...
</form>

Save multiple sheets to .pdf

I recommend adding the following line after the export to PDF:

ThisWorkbook.Sheets("Sheet1").Select

(where eg. Sheet1 is the single sheet you want to be active afterwards)

Leaving multiple sheets in a selected state may cause problems executing some code. (eg. unprotect doesn't function properly when multiple sheets are actively selected.)

How to check if a .txt file is in ASCII or UTF-8 format in Windows environment?

If you use Windows 10 and has Windows Subsystem for Linux (WSL), it can be easily done by typing "file " from the shell.

For example:

$ file code.cpp

code.cpp: C source, UTF-8 Unicode (with BOM) text, with CRLF line terminators

How to install XNA game studio on Visual Studio 2012?

There seems to be some confusion over how to get this set up for the Express version specifically. Using the Windows Desktop (WD) version of VS Express 2012, I followed the instructions in Steve B's and Rick Martin's answers with the modifications below.

  • In step 2 rather than copying to "C:\Program Files (x86)\Microsoft Visual Studio 11.0\Common7\IDE\Extensions\Microsoft\XNA Game Studio 4.0", copy to "C:\Program Files (x86)\Microsoft Visual Studio 11.0\Common7\IDE\WDExpressExtensions\Microsoft\XNA Game Studio 4.0"
  • In step 4, after making the changes also add the line <Edition>WDExpress</Edition> (you should be able to see where it makes sense)
  • In step 5, replace devenv.exe with WDExpress.exe
  • In Rick Martin's step, replace "%LocalAppData%\Microsoft\VisualStudio\11.0\Extensions" with "%LocalAppData%\Microsoft\WDExpress\11.0\Extensions"

I haven't done a lot of work since then, but I did manage to create a new game project and it seems fine so far.

Creating a new column based on if-elif-else condition

To formalize some of the approaches laid out above:

Create a function that operates on the rows of your dataframe like so:

def f(row):
    if row['A'] == row['B']:
        val = 0
    elif row['A'] > row['B']:
        val = 1
    else:
        val = -1
    return val

Then apply it to your dataframe passing in the axis=1 option:

In [1]: df['C'] = df.apply(f, axis=1)

In [2]: df
Out[2]:
   A  B  C
a  2  2  0
b  3  1  1
c  1  3 -1

Of course, this is not vectorized so performance may not be as good when scaled to a large number of records. Still, I think it is much more readable. Especially coming from a SAS background.

Edit

Here is the vectorized version

df['C'] = np.where(
    df['A'] == df['B'], 0, np.where(
    df['A'] >  df['B'], 1, -1)) 

variable is not declared it may be inaccessible due to its protection level

I have found that you have to comment out the namespace wrapping the the class at time when moving between version of Visual Studio:

'Namespace FormsAuth

'End Namespace

and at other times, I have to uncomment the namespace.

This happened to me several times when other developers edited the same solution using a different version of VS and/or I moved (copied) the solution to another location

SVN Repository on Google Drive or DropBox

While possible, it's potentially very risky - if you attempt to commit changes to the repository from 2 different locations simultaneously, you'll get a giant mess due to the file conflicts. Get a free private SVN host somewhere, or set up a repository on a server you have access to.

Edit based on a recent experience: If you have files open that are managed by Dropbox and your computer crashes, your files may be truncated to 0 bytes. If this happens to the files which manage your repository, your repository will be corrupted. If you discover this soon enough, you can use Dropbox's "recover old version" feature but you're still taking a risk.

Java how to replace 2 or more spaces with single space in string and delete leading and trailing spaces

String str = "  this is string   ";
str = str.replaceAll("\\s+", " ").trim();

"No backupset selected to be restored" SQL Server 2012

FYI: I found that when restoring, I needed to use the same (SQL User) credentials to login to SSMS. I had first tried the restore using a Windows Authentication account.

Why is vertical-align:text-top; not working in CSS

The problem I had can't be made out from the info I have provided:

  • I had the text enclosed in old school <p> tags.

I changed the <p> to <span> and it works fine.

Align text in a table header

If you want to center the th of all tables:
table th{ text-align: center; }

If you only want to center the th of a table with a determined id:
table#tableId th{ text-align: center; }

Switch on ranges of integers in JavaScript

This does not require a switch statement. It is clearer, more concise, faster, and optimises better, to use if else statements...

var d = this.dealer;
if (1 <= d && d <= 11) { // making sure in range 1..11
    if (d <= 4) {
        alert("1 to 4");
    } else if (d <= 8) {
        alert("5 to 8");
    } else {
        alert("9 to 11");
    }
} else {
    alert("not in range");
}

Speed test

I was curious about the overhead of using a switch instead of the simpler if...else..., so I put together a jsFiddle to examine it... http://jsfiddle.net/17x9w1eL/

  • Chrome: switch was around 70% slower than if else

  • Firefox: switch was around 5% slower than if else

  • IE: switch was around 5% slower than if else

  • Safari: switch was around 95% slower than if else

Notes:

Assigning to the local variable is optional, especially if your code is going to be automatically optimised later.

For numeric ranges, I like to use this kind of construction...

if (1 <= d && d <= 11) {...}

... because to me it reads closer to the way you would express a range in maths (1 <= d <= 11), and when I'm reading the code, I can read that as "if d is between 1 and 11".

Clearer

A few people don't think this is clearer. I'd say it is not less clear as the structure is close to identical to the switch option. The main reason it is clearer is that every part of it is readable and makes simple intuitive sense.

My concern, with "switch (true)", is that it can appear to be a meaningless line of code. Many coders, reading that will not know what to make of it.

For my own code, I'm more willing to use obscure structures from time to time, but if anyone else will look at it, I try to use clearer constructs. I think it is better to use the constructs for what they are intended.

Optimisation

In a modern environment, code is often going to be minified for production, so you can write clear concise code, with readable variable names and helpful comments. There's no clear reason to use switch in this way.

I also tried putting both constructs through a minifier. The if/else structure compresses well, becoming a single short expression using nested ternary operators. The switch statement when minified remains a switch, complete with "switch", "case" and "break" tokens, and as a result is considerably longer in code.

How switch(true) works

I think "switch(true) is obscure, but it seems some people just want to use it, so here's an explanation of why it works...

A switch/case statement works by matching the part in the switch with each case, and then executing the code on the first match. In most use cases, we have a variable or non-constant expression in the switch, and then match it.

With "switch(true), we will find the first expression in the case statements that is true. If you read "switch (true)" as "find the first expression that is true", the code feels more readable.

How do I display image in Alert/confirm box in Javascript?

Snarky yet potentially useful answer: http://picascii.com/ (currently down)

https://www.ascii-art-generator.org/es.html (don't forget to put a \n after each line!)

slf4j: how to log formatted message, object array, exception

As of SLF4J 1.6.0, in the presence of multiple parameters and if the last argument in a logging statement is an exception, then SLF4J will presume that the user wants the last argument to be treated as an exception and not a simple parameter. See also the relevant FAQ entry.

So, writing (in SLF4J version 1.7.x and later)

 logger.error("one two three: {} {} {}", "a", "b", 
              "c", new Exception("something went wrong"));

or writing (in SLF4J version 1.6.x)

 logger.error("one two three: {} {} {}", new Object[] {"a", "b", 
              "c", new Exception("something went wrong")});

will yield

one two three: a b c
java.lang.Exception: something went wrong
    at Example.main(Example.java:13)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at ...

The exact output will depend on the underlying framework (e.g. logback, log4j, etc) as well on how the underlying framework is configured. However, if the last parameter is an exception it will be interpreted as such regardless of the underlying framework.

jquery can't get data attribute value

Use plain javascript methods

$x10Device = this.dataset("x10");

warning: incompatible implicit declaration of built-in function ‘xyz’

I met these warnings on mempcpy function. Man page says this function is a GNU extension and synopsis shows:

#define _GNU_SOURCE
#include <string.h>

When #define is added to my source before the #include, declarations for the GNU extensions are made visible and warnings disappear.

How to print the value of a Tensor object in TensorFlow?

I think you need to get some fundamentals right. With the examples above you have created tensors (multi dimensional array). But for tensor flow to really work you have to initiate a "session" and run your "operation" in the session. Notice the word "session" and "operation". You need to know 4 things to work with tensorflow:

  1. tensors
  2. Operations
  3. Sessions
  4. Graphs

Now from what you wrote out you have given the tensor, and the operation but you have no session running nor a graph. Tensor (edges of the graph) flow through graphs and are manipulated by operations (nodes of the graph). There is default graph but you can initiate yours in a session.

When you say print , you only access the shape of the variable or constant you defined.

So you can see what you are missing :

 with tf.Session() as sess:     
           print(sess.run(product))
           print (product.eval())

Hope it helps!

Avoid duplicates in INSERT INTO SELECT query in SQL Server

In MySQL you can do this:

INSERT IGNORE INTO Table2(Id, Name) SELECT Id, Name FROM Table1

Does SQL Server have anything similar?

How to set timeout for a line of c# code

You can use the IAsyncResult and Action class/interface to achieve this.

public void TimeoutExample()
{
    IAsyncResult result;
    Action action = () =>
    {
        // Your code here
    };

    result = action.BeginInvoke(null, null);

    if (result.AsyncWaitHandle.WaitOne(10000))
         Console.WriteLine("Method successful.");
    else
         Console.WriteLine("Method timed out.");
}

Parsing a JSON string in Ruby

As of Ruby v1.9.3 you don't need to install any Gems in order to parse JSON, simply use require 'json':

require 'json'

json = JSON.parse '{"foo":"bar", "ping":"pong"}'
puts json['foo'] # prints "bar"

See JSON at Ruby-Doc.

How to insert TIMESTAMP into my MySQL table?

The DEFAULT value of a column in MySql is used only if it isn't provided a value for that column. So if you

INSERT INTO contactinfo (name, email, subject, date, comments)
VALUES ('$name', '$email', '$subject', '', '$comments')

You are not using the DEFAULT value for the column date, but you are providing an empty string, so you get an error, because you can't store an empty string in a DATETIME column. The same thing apply if you use NULL, because again NULL is a value. However, if you remove the column from the list of the column you are inserting, MySql will use the DEFAULT value specified for that column (or the data type default one)

HTML5 tag for horizontal line break

I am answering this old question just because it still shows up in google queries and I think one optimal answer is missing. Try this code: use ::before or ::after

See Align <hr> to the left in an HTML5-compliant way

Spring Boot application as a Service

It can be done using Systemd service in Ubuntu

[Unit]
Description=A Spring Boot application
After=syslog.target

[Service]
User=baeldung
ExecStart=/path/to/your-app.jar SuccessExitStatus=143

[Install] 
WantedBy=multi-user.target

You can follow this link for more elaborated description and different ways to do so. http://www.baeldung.com/spring-boot-app-as-a-service

What is the theoretical maximum number of open TCP connections that a modern Linux box can have

A single listening port can accept more than one connection simultaneously.

There is a '64K' limit that is often cited, but that is per client per server port, and needs clarifying.

Each TCP/IP packet has basically four fields for addressing. These are:

source_ip source_port destination_ip destination_port
<----- client ------> <--------- server ------------>

Inside the TCP stack, these four fields are used as a compound key to match up packets to connections (e.g. file descriptors).

If a client has many connections to the same port on the same destination, then three of those fields will be the same - only source_port varies to differentiate the different connections. Ports are 16-bit numbers, therefore the maximum number of connections any given client can have to any given host port is 64K.

However, multiple clients can each have up to 64K connections to some server's port, and if the server has multiple ports or either is multi-homed then you can multiply that further.

So the real limit is file descriptors. Each individual socket connection is given a file descriptor, so the limit is really the number of file descriptors that the system has been configured to allow and resources to handle. The maximum limit is typically up over 300K, but is configurable e.g. with sysctl.

The realistic limits being boasted about for normal boxes are around 80K for example single threaded Jabber messaging servers.

Generic Interface

I'd stay with two different interfaces.

You said that 'I want to group my service executors under a common interface... It also seems overkill creating two separate interfaces for the two different service calls... A class will only implement one of these interfaces'

It's not clear what is the reason to have a single interface then. If you want to use it as a marker, you can just exploit annotations instead.

Another point is that there is a possible case that your requirements change and method(s) with another signature appears at the interface. Of course it's possible to use Adapter pattern then but it would be rather strange to see that particular class implements interface with, say, three methods where two of them trow UnsupportedOperationException. It's possible that the forth method appears etc.

How to install Hibernate Tools in Eclipse?

Since it is for Ganymede (eclipse 3.4), I would advise to uncompress the zip in the dropins in the HibernateTools-3.2.4.Beta1-R20081031133 directory created after the name of the archive.

Once it is done, create in the [eclipse\dropins\HibernateTools-3.2.4.Beta1-R20081031133] an 'eclipse' directory, in which you will move the plugins and features directories creating at the extraction of the files of the archive.

Add a .exclipseextension in [eclipse\dropins\HibernateTools-3.2.4.Beta1-R20081031133\eclipse]:

name=QuickRex
id=org.hibernate.eclipse
version=3.2.4b1

So:

eclipse
    dropins
         HibernateTools-3.2.4.Beta1-R20081031133
             eclipse
                 .eclipseextension
                 features
                 plugins

Relaunch eclipse and the plugin Hibernate should be detected.

If you install another eclipse, just copy the content of your dropins directory to the new eclipse\dropins and your set of plugins will be detected again.

How to unload a package without restarting R

I tried what kohske wrote as an answer and I got error again, so I did some search and found this which worked for me (R 3.0.2):

require(splines) # package
detach(package:splines)

or also

library(splines)
pkg <- "package:splines"
detach(pkg, character.only = TRUE)

Which ORM should I use for Node.js and MySQL?

May I suggest Node ORM?

https://github.com/dresende/node-orm2

There's documentation on the Readme, supports MySQL, PostgreSQL and SQLite.

MongoDB is available since version 2.1.x (released in July 2013)

UPDATE: This package is no longer maintained, per the project's README. It instead recommends bookshelf and sequelize

How to get HttpContext.Current in ASP.NET Core?

As a general rule, converting a Web Forms or MVC5 application to ASP.NET Core will require a significant amount of refactoring.

HttpContext.Current was removed in ASP.NET Core. Accessing the current HTTP context from a separate class library is the type of messy architecture that ASP.NET Core tries to avoid. There are a few ways to re-architect this in ASP.NET Core.

HttpContext property

You can access the current HTTP context via the HttpContext property on any controller. The closest thing to your original code sample would be to pass HttpContext into the method you are calling:

public class HomeController : Controller
{
    public IActionResult Index()
    {
        MyMethod(HttpContext);

        // Other code
    }
}

public void MyMethod(Microsoft.AspNetCore.Http.HttpContext context)
{
    var host = $"{context.Request.Scheme}://{context.Request.Host}";

    // Other code
}

HttpContext parameter in middleware

If you're writing custom middleware for the ASP.NET Core pipeline, the current request's HttpContext is passed into your Invoke method automatically:

public Task Invoke(HttpContext context)
{
    // Do something with the current HTTP context...
}

HTTP context accessor

Finally, you can use the IHttpContextAccessor helper service to get the HTTP context in any class that is managed by the ASP.NET Core dependency injection system. This is useful when you have a common service that is used by your controllers.

Request this interface in your constructor:

public MyMiddleware(IHttpContextAccessor httpContextAccessor)
{
    _httpContextAccessor = httpContextAccessor;
}

You can then access the current HTTP context in a safe way:

var context = _httpContextAccessor.HttpContext;
// Do something with the current HTTP context...

IHttpContextAccessor isn't always added to the service container by default, so register it in ConfigureServices just to be safe:

public void ConfigureServices(IServiceCollection services)
{
    services.AddHttpContextAccessor();
    // if < .NET Core 2.2 use this
    //services.TryAddSingleton<IHttpContextAccessor, HttpContextAccessor>();

    // Other code...
}

failed to open stream: No such file or directory in

you can use:

define("PATH_ROOT", dirname(__FILE__));
include_once PATH_ROOT . "/PoliticalForum/headerSite.php";

moment.js 24h format

HH used 24 hour format while hh used for 12 format

open new tab(window) by clicking a link in jquery

Try this:

window.open(url, '_blank');

This will open in new tab (if your code is synchronous and in this case it is. in other case it would open a window)

Send and receive messages through NSNotificationCenter in Objective-C?

SWIFT 5.1 of selected answer for newbies

class TestClass {
    deinit {
        // If you don't remove yourself as an observer, the Notification Center
        // will continue to try and send notification objects to the deallocated
        // object.
        NotificationCenter.default.removeObserver(self)
    }

    init() {
        super.init()

        // Add this instance of TestClass as an observer of the TestNotification.
        // We tell the notification center to inform us of "TestNotification"
        // notifications using the receiveTestNotification: selector. By
        // specifying object:nil, we tell the notification center that we are not
        // interested in who posted the notification. If you provided an actual
        // object rather than nil, the notification center will only notify you
        // when the notification was posted by that particular object.

        NotificationCenter.default.addObserver(self, selector: #selector(receiveTest(_:)), name: NSNotification.Name("TestNotification"), object: nil)
    }

    @objc func receiveTest(_ notification: Notification?) {
        // [notification name] should always be @"TestNotification"
        // unless you use this method for observation of other notifications
        // as well.

        if notification?.name.isEqual(toString: "TestNotification") != nil {
            print("Successfully received the test notification!")
        }
    }
}

... somewhere else in another class ...

 func someMethod(){
        // All instances of TestClass will be notified
        NotificationCenter.default.post(name: NSNotification.Name(rawValue: "TestNotification"), object: self)
 }