Programs & Examples On #Nspopupbutton

The NSPopUpButton class defines objects that implement the pop-up and pull-down menus of the graphical user interface.

How to move up a directory with Terminal in OS X

Let's make it even more simple. Type the below after the $ sign to go up one directory:

../

Angular 2: Can't bind to 'ngModel' since it isn't a known property of 'input'

Let’s assume, your old app.module.ts may look similar to this :

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';

@NgModule({
    imports: [ BrowserModule ],
    declarations: [ AppComponent ],
    bootstrap: [ AppComponent ]
})

export class AppModule { }

Now import FormsModule in your app.module.ts

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';
import { AppComponent } from './app.component';

@NgModule({
    imports: [ BrowserModule, FormsModule ],
    declarations: [ AppComponent ],
    bootstrap: [ AppComponent ]
})

export class AppModule { }

http://jsconfig.com/solution-cant-bind-ngmodel-since-isnt-known-property-input/

Convert an integer to a byte array

I agree with Brainstorm's approach: assuming that you're passing a machine-friendly binary representation, use the encoding/binary library. The OP suggests that binary.Write() might have some overhead. Looking at the source for the implementation of Write(), I see that it does some runtime decisions for maximum flexibility.

func Write(w io.Writer, order ByteOrder, data interface{}) error {
    // Fast path for basic types.
    var b [8]byte
    var bs []byte
    switch v := data.(type) {
    case *int8:
        bs = b[:1]
        b[0] = byte(*v)
    case int8:
        bs = b[:1]
        b[0] = byte(v)
    case *uint8:
        bs = b[:1]
        b[0] = *v
    ...

Right? Write() takes in a very generic data third argument, and that's imposing some overhead as the Go runtime then is forced into encoding type information. Since Write() is doing some runtime decisions here that you simply don't need in your situation, maybe you can just directly call the encoding functions and see if it performs better.

Something like this:

package main

import (
    "encoding/binary"
    "fmt"
)

func main() {
    bs := make([]byte, 4)
    binary.LittleEndian.PutUint32(bs, 31415926)
    fmt.Println(bs)
}

Let us know how this performs.

Otherwise, if you're just trying to get an ASCII representation of the integer, you can get the string representation (probably with strconv.Itoa) and cast that string to the []byte type.

package main

import (
    "fmt"
    "strconv"
)

func main() {
    bs := []byte(strconv.Itoa(31415926))
    fmt.Println(bs)
}

Git error: src refspec master does not match any error: failed to push some refs

One classic root cause for this message is:

  • when the repo has been initialized (git init lis4368/assignments),
  • but no commit has ever been made

Ie, if you don't have added and committed at least once, there won't be a local master branch to push to.

Try first to create a commit:

  • either by adding (git add .) then git commit -m "first commit"
    (assuming you have the right files in place to add to the index)
  • or by create a first empty commit: git commit --allow-empty -m "Initial empty commit"

And then try git push -u origin master again.

See "Why do I need to explicitly push a new branch?" for more.

MongoDB: Combine data from multiple collections into one..how?

Mongorestore has this feature of appending on top of whatever is already in the database, so this behavior could be used for combining two collections:

  1. mongodump collection1
  2. collection2.rename(collection1)
  3. mongorestore

Didn't try it yet, but it might perform faster than the map/reduce approach.

How to find children of nodes using BeautifulSoup

There's a super small section in the DOCs that shows how to find/find_all direct children.

https://www.crummy.com/software/BeautifulSoup/bs4/doc/#the-recursive-argument

In your case as you want link1 which is first direct child:

# for only first direct child
soup.find("li", { "class" : "test" }).find("a", recursive=False)

If you want all direct children:

# for all direct children
soup.find("li", { "class" : "test" }).findAll("a", recursive=False)

Remove shadow below actionbar

What is the style item to make it disappear?

In order to remove the shadow add this to your app theme:

<style name="MyAppTheme" parent="android:Theme.Holo.Light">
    <item name="android:windowContentOverlay">@null</item>
</style>

UPDATE: As @Quinny898 stated, on Android 5.0 this has changed, you have to call setElevation(0) on your action bar. Note that if you're using the support library you must call it to that like so:

getSupportActionBar().setElevation(0);

Resize a picture to fit a JLabel

Assign your image to a string. Eg image Now set icon to a fixed size label.

image.setIcon(new javax.swing.ImageIcon(image.getScaledInstance(50,50,WIDTH)));

How to create string with multiple spaces in JavaScript

In 2021 - use ES6 Template Literals for this task. If you need IE11 Support - use a transpiler.

let a = `something       something`;

Template Literals are fast, powerful and produce cleaner code.


If you need IE11 support and you don't have transpiler, stay strong and use \xa0 - it is a NO-BREAK SPACE char.

Reference from UTF-8 encoding table and Unicode characters, you can write as below:

var a = 'something' + '\xa0\xa0\xa0\xa0\xa0\xa0\xa0' + 'something';

What is uintptr_t data type

There are already many good answers to the part "what is uintptr_t data type". I will try to address the "what it can be used for?" part in this post.

Primarily for bitwise operations on pointers. Remember that in C++ one cannot perform bitwise operations on pointers. For reasons see Why can't you do bitwise operations on pointer in C, and is there a way around this?

Thus in order to do bitwise operations on pointers one would need to cast pointers to type unitpr_t and then perform bitwise operations.

Here is an example of a function that I just wrote to do bitwise exclusive or of 2 pointers to store in a XOR linked list so that we can traverse in both directions like a doubly linked list but without the penalty of storing 2 pointers in each node.

 template <typename T>
 T* xor_ptrs(T* t1, T* t2)
 {
     return reinterpret_cast<T*>(reinterpret_cast<uintptr_t>(t1)^reinterpret_cast<uintptr_t>(t2));
  }

unique() for more than one variable

This is an addition to Josh's answer.

You can also keep the values of other variables while filtering out duplicated rows in data.table

Example:

library(data.table)

#create data table
dt <- data.table(
  V1=LETTERS[c(1,1,1,1,2,3,3,5,7,1)],
  V2=LETTERS[c(2,3,4,2,1,4,4,6,7,2)],
  V3=c(1),
  V4=c(2) )

> dt
# V1 V2 V3 V4
# A  B  1  2
# A  C  1  2
# A  D  1  2
# A  B  1  2
# B  A  1  2
# C  D  1  2
# C  D  1  2
# E  F  1  2
# G  G  1  2
# A  B  1  2

# set the key to all columns
setkey(dt)

# Get Unique lines in the data table
unique( dt[list(V1, V2), nomatch = 0] ) 

# V1 V2 V3 V4
# A  B  1  2
# A  C  1  2
# A  D  1  2
# B  A  1  2
# C  D  1  2
# E  F  1  2
# G  G  1  2

Alert: If there are different combinations of values in the other variables, then your result will be

unique combination of V1 and V2

How to access data/data folder in Android device?

You can also try copying the file to the SD Card folder, which is a public folder, then you can copy the file to your PC where you can use sqlite to access it.

Here is some code you can use to copy the file from data/data to a public storage folder:

private void copyFile(final Context context) {
    try {
        File sd = Environment.getExternalStorageDirectory();
        File data = Environment.getDataDirectory();

        if (sd.canWrite()) {
            String currentDBPath =
                    context.getDatabasePath(DATABASE_NAME).getAbsolutePath();

            String backupDBPath = "data.db";

            File currentDB = new File(currentDBPath);
            File backupDB = new File(sd, backupDBPath);

            if (currentDB.exists()) {
                FileChannel src = new FileInputStream(currentDB).getChannel();
                FileChannel dst = new FileOutputStream(backupDB).getChannel();
                dst.transferFrom(src, 0, src.size());
                src.close();
                dst.close();
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
}

Manifest:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_INTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_INTERNAL_STORAGE" />

Convert from lowercase to uppercase all values in all character variables in dataframe

Another alternative is to use a combination of mutate_if() and str_to_uper() function, both from the tidyverse package:

df %>% mutate_if(is.character, str_to_upper) -> df

This will convert all string variables in the data frame to upper case. str_to_lower() do the opposite.

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

Docker-compose: node_modules not present in a volume after npm install succeeds

There are two seperate requirements I see for node dev environments... mount your source code INTO the container, and mount the node_modules FROM the container (for your IDE). To accomplish the first, you do the usual mount, but not everything... just the things you need

volumes:
    - worker/src:/worker/src
    - worker/package.json:/worker/package.json
    - etc...

( the reason to not do - /worker/node_modules is because docker-compose will persist that volume between runs, meaning you can diverge from what is actually in the image (defeating the purpose of not just bind mounting from your host)).

The second one is actually harder. My solution is a bit hackish, but it works. I have a script to install the node_modules folder on my host machine, and I just have to remember to call it whenever I update package.json (or, add it to the make target that runs docker-compose build locally).

install_node_modules:
    docker build -t building .
    docker run -v `pwd`/node_modules:/app/node_modules building npm install

Why does datetime.datetime.utcnow() not contain timezone information?

from datetime import datetime 
from dateutil.relativedelta import relativedelta
d = datetime.now()
date = datetime.isoformat(d).split('.')[0]
d_month = datetime.today() + relativedelta(months=1)
next_month = datetime.isoformat(d_month).split('.')[0]

How to get the current location latitude and longitude in android

try this, hope it will help you to get the current location, every time the location changes.

public class MyClass implements LocationListener {
    double currentLatitude, currentLongitude;

    public void onLocationChanged(Location location) {
        currentLatitude = location.getLatitude();
        currentLongitude = location.getLongitude();
    }
}

IllegalArgumentException or NullPointerException for a null parameter?

You should throw an IllegalArgumentException, as it will make it obvious to the programmer that he has done something invalid. Developers are so used to seeing NPE thrown by the VM, that any programmer would not immediately realize his error, and would start looking around randomly, or worse, blame your code for being 'buggy'.

Getting path relative to the current working directory?

You can use Environment.CurrentDirectory to get the current directory, and FileSystemInfo.FullPath to get the full path to any location. So, fully qualify both the current directory and the file in question, and then check whether the full file name starts with the directory name - if it does, just take the appropriate substring based on the directory name's length.

Here's some sample code:

using System;
using System.IO;

class Program
{
    public static void Main(string[] args)
    {
        string currentDir = Environment.CurrentDirectory;
        DirectoryInfo directory = new DirectoryInfo(currentDir);
        FileInfo file = new FileInfo(args[0]);

        string fullDirectory = directory.FullName;
        string fullFile = file.FullName;

        if (!fullFile.StartsWith(fullDirectory))
        {
            Console.WriteLine("Unable to make relative path");
        }
        else
        {
            // The +1 is to avoid the directory separator
            Console.WriteLine("Relative path: {0}",
                              fullFile.Substring(fullDirectory.Length+1));
        }
    }
}

I'm not saying it's the most robust thing in the world (symlinks could probably confuse it) but it's probably okay if this is just a tool you'll be using occasionally.

Add newline to VBA or Visual Basic 6

Use this code between two words:

& vbCrLf &

Using this, the next word displays on the next line.

iOS: Convert UTC NSDate to local Timezone

NSTimeInterval seconds; // assume this exists
NSDate* ts_utc = [NSDate dateWithTimeIntervalSince1970:seconds];

NSDateFormatter* df_utc = [[[NSDateFormatter alloc] init] autorelease];
[df_utc setTimeZone:[NSTimeZone timeZoneWithName:@"UTC"]];
[df_utc setDateFormat:@"yyyy.MM.dd G 'at' HH:mm:ss zzz"];

NSDateFormatter* df_local = [[[NSDateFormatter alloc] init] autorelease];
[df_local setTimeZone:[NSTimeZone timeZoneWithName:@"EST"]];
[df_local setDateFormat:@"yyyy.MM.dd G 'at' HH:mm:ss zzz"];

NSString* ts_utc_string = [df_utc stringFromDate:ts_utc];
NSString* ts_local_string = [df_local stringFromDate:ts_utc];

// you can also use NSDateFormatter dateFromString to go the opposite way

Table of formatting string parameters:

https://waracle.com/iphone-nsdateformatter-date-formatting-table/

If performance is a priority, you may want to consider using strftime

https://developer.apple.com/legacy/library/documentation/Darwin/Reference/ManPages/man3/strftime.3.html

How to evaluate a math expression given in string form?

It's too late to answer but I came across same situation to evaluate expression in java, it might help someone

MVEL does runtime evaluation of expressions, we can write a java code in String to get it evaluated in this.

    String expressionStr = "x+y";
    Map<String, Object> vars = new HashMap<String, Object>();
    vars.put("x", 10);
    vars.put("y", 20);
    ExecutableStatement statement = (ExecutableStatement) MVEL.compileExpression(expressionStr);
    Object result = MVEL.executeExpression(statement, vars);

How can I load Partial view inside the view?

If you want to load the partial view directly inside the main view you could use the Html.Action helper:

@Html.Action("Load", "Home")

or if you don't want to go through the Load action use the HtmlPartialAsync helper:

@await Html.PartialAsync("_LoadView")

If you want to use Ajax.ActionLink, replace your Html.ActionLink with:

@Ajax.ActionLink(
    "load partial view", 
    "Load", 
    "Home", 
    new AjaxOptions { UpdateTargetId = "result" }
)

and of course you need to include a holder in your page where the partial will be displayed:

<div id="result"></div>

Also don't forget to include:

<script src="@Url.Content("~/Scripts/jquery.unobtrusive-ajax.js")" type="text/javascript"></script>

in your main view in order to enable Ajax.* helpers. And make sure that unobtrusive javascript is enabled in your web.config (it should be by default):

<add key="UnobtrusiveJavaScriptEnabled" value="true" />

Concatenate rows of two dataframes in pandas

call concat and pass param axis=1 to concatenate column-wise:

In [5]:

pd.concat([df_a,df_b], axis=1)
Out[5]:
        AAseq Biorep  Techrep Treatment     mz      AAseq1 Biorep1  Techrep1  \
0  ELVISLIVES      A        1         C  500.0  ELVISLIVES       A         1   
1  ELVISLIVES      A        1         C  500.5  ELVISLIVES       A         1   
2  ELVISLIVES      A        1         C  501.0  ELVISLIVES       A         1   

  Treatment1  inte1  
0          C   1100  
1          C   1050  
2          C   1010  

There is a useful guide to the various methods of merging, joining and concatenating online.

For example, as you have no clashing columns you can merge and use the indices as they have the same number of rows:

In [6]:

df_a.merge(df_b, left_index=True, right_index=True)
Out[6]:
        AAseq Biorep  Techrep Treatment     mz      AAseq1 Biorep1  Techrep1  \
0  ELVISLIVES      A        1         C  500.0  ELVISLIVES       A         1   
1  ELVISLIVES      A        1         C  500.5  ELVISLIVES       A         1   
2  ELVISLIVES      A        1         C  501.0  ELVISLIVES       A         1   

  Treatment1  inte1  
0          C   1100  
1          C   1050  
2          C   1010  

And for the same reasons as above a simple join works too:

In [7]:

df_a.join(df_b)
Out[7]:
        AAseq Biorep  Techrep Treatment     mz      AAseq1 Biorep1  Techrep1  \
0  ELVISLIVES      A        1         C  500.0  ELVISLIVES       A         1   
1  ELVISLIVES      A        1         C  500.5  ELVISLIVES       A         1   
2  ELVISLIVES      A        1         C  501.0  ELVISLIVES       A         1   

  Treatment1  inte1  
0          C   1100  
1          C   1050  
2          C   1010  

What are naming conventions for MongoDB?

  1. Keep'em short: Optimizing Storage of Small Objects, SERVER-863. Silly but true.

  2. I guess pretty much the same rules that apply to relation databases should apply here. And after so many decades there is still no agreement whether RDBMS tables should be named singular or plural...

  3. MongoDB speaks JavaScript, so utilize JS naming conventions of camelCase.

  4. MongoDB official documentation mentions you may use underscores, also built-in identifier is named _id (but this may be be to indicate that _id is intended to be private, internal, never displayed or edited.

How to convert an XML file to nice pandas dataframe?

You can easily use xml (from the Python standard library) to convert to a pandas.DataFrame. Here's what I would do (when reading from a file replace xml_data with the name of your file or file object):

import pandas as pd
import xml.etree.ElementTree as ET
import io

def iter_docs(author):
    author_attr = author.attrib
    for doc in author.iter('document'):
        doc_dict = author_attr.copy()
        doc_dict.update(doc.attrib)
        doc_dict['data'] = doc.text
        yield doc_dict

xml_data = io.StringIO(u'''\
<author type="XXX" language="EN" gender="xx" feature="xx" web="foobar.com">
    <documents count="N">
        <document KEY="e95a9a6c790ecb95e46cf15bee517651" web="www.foo_bar_exmaple.com"><![CDATA[A large text with lots of strings and punctuations symbols [...]
]]>
        </document>
        <document KEY="bc360cfbafc39970587547215162f0db" web="www.foo_bar_exmaple.com"><![CDATA[A large text with lots of strings and punctuations symbols [...]
]]>
        </document>
        <document KEY="19e71144c50a8b9160b3f0955e906fce" web="www.foo_bar_exmaple.com"><![CDATA[A large text with lots of strings and punctuations symbols [...]
]]>
        </document>
        <document KEY="21d4af9021a174f61b884606c74d9e42" web="www.foo_bar_exmaple.com"><![CDATA[A large text with lots of strings and punctuations symbols [...]
]]>
        </document>
        <document KEY="28a45eb2460899763d709ca00ddbb665" web="www.foo_bar_exmaple.com"><![CDATA[A large text with lots of strings and punctuations symbols [...]
]]>
        </document>
        <document KEY="a0c0712a6a351f85d9f5757e9fff8946" web="www.foo_bar_exmaple.com"><![CDATA[A large text with lots of strings and punctuations symbols [...]
]]>
        </document>
        <document KEY="626726ba8d34d15d02b6d043c55fe691" web="www.foo_bar_exmaple.com"><![CDATA[A large text with lots of strings and punctuations symbols [...]
]]>
        </document>
        <document KEY="2cb473e0f102e2e4a40aa3006e412ae4" web="www.foo_bar_exmaple.com"><![CDATA[A large text with lots of strings and punctuations symbols [...] [...]
]]>
        </document>
    </documents>
</author>
''')

etree = ET.parse(xml_data) #create an ElementTree object 
doc_df = pd.DataFrame(list(iter_docs(etree.getroot())))

If there are multiple authors in your original document or the root of your XML is not an author, then I would add the following generator:

def iter_author(etree):
    for author in etree.iter('author'):
        for row in iter_docs(author):
            yield row

and change doc_df = pd.DataFrame(list(iter_docs(etree.getroot()))) to doc_df = pd.DataFrame(list(iter_author(etree)))

Have a look at the ElementTree tutorial provided in the xml library documentation.

CSS set li indent

Also try:

ul {
  list-style-position: inside;
}

Node.js client for a socket.io server

Adding in example for solution given earlier. By using socket.io-client https://github.com/socketio/socket.io-client

Client Side:

//client.js
var io = require('socket.io-client');
var socket = io.connect('http://localhost:3000', {reconnect: true});

// Add a connect listener
socket.on('connect', function (socket) {
    console.log('Connected!');
});
socket.emit('CH01', 'me', 'test msg');

Server Side :

//server.js
var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);

io.on('connection', function (socket){
   console.log('connection');

  socket.on('CH01', function (from, msg) {
    console.log('MSG', from, ' saying ', msg);
  });

});

http.listen(3000, function () {
  console.log('listening on *:3000');
});

Run :

Open 2 console and run node server.js and node client.js

Using generic std::function objects with member functions in one class

If you need to store a member function without the class instance, you can do something like this:

class MyClass
{
public:
    void MemberFunc(int value)
    {
      //do something
    }
};

// Store member function binding
auto callable = std::mem_fn(&MyClass::MemberFunc);

// Call with late supplied 'this'
MyClass myInst;
callable(&myInst, 123);

What would the storage type look like without auto? Something like this:

std::_Mem_fn_wrap<void,void (__cdecl TestA::*)(int),TestA,int> callable

You can also pass this function storage to a standard function binding

std::function<void(int)> binding = std::bind(callable, &testA, std::placeholders::_1);
binding(123); // Call

Past and future notes: An older interface std::mem_func existed, but has since been deprecated. A proposal exists, post C++17, to make pointer to member functions callable. This would be most welcome.

What happens to C# Dictionary<int, int> lookup if the key does not exist?

The Dictionary throws a KeyNotFound exception in the event that the dictionary does not contain your key.

As suggested, ContainsKey is the appropriate precaution. TryGetValue is also effective.

This allows the dictionary to store a value of null more effectively. Without it behaving this way, checking for a null result from the [] operator would indicate either a null value OR the non-existance of the input key which is no good.

jQuery: If this HREF contains

Along with the points made by others, the $= selector is the "ends with" selector. You will want the *= (contains) selector, like so:

$('a').each(function() {
    if ($(this).is('[href*="?"')) {
        alert("Contains questionmark");
    }
});

Here's a live demo ->

As noted by Matt Ball, unless you will need to also manipulate links without a question mark (which may be the case, since you say your example is simplified), it would be less code and much faster to simply select only the links you want to begin with:

$('a[href*="?"]').each(function() {
    alert("Contains questionmark");
});

How can I combine flexbox and vertical scroll in a full-height app?

Thanks to https://stackoverflow.com/users/1652962/cimmanon that gave me the answer.

The solution is setting a height to the vertical scrollable element. For example:

#container article {
    flex: 1 1 auto;
    overflow-y: auto;
    height: 0px;
}

The element will have height because flexbox recalculates it unless you want a min-height so you can use height: 100px; that it is exactly the same as: min-height: 100px;

#container article {
    flex: 1 1 auto;
    overflow-y: auto;
    height: 100px; /* == min-height: 100px*/
}

So the best solution if you want a min-height in the vertical scroll:

#container article {
    flex: 1 1 auto;
    overflow-y: auto;
    min-height: 100px;
}

If you just want full vertical scroll in case there is no enough space to see the article:

#container article {
    flex: 1 1 auto;
    overflow-y: auto;
    min-height: 0px;
}

The final code: http://jsfiddle.net/ch7n6/867/

DeprecationWarning: Buffer() is deprecated due to security and usability issues when I move my script to another server

The use of the deprecated new Buffer() constructor (i.E. as used by Yarn) can cause deprecation warnings. Therefore one should NOT use the deprecated/unsafe Buffer constructor.

According to the deprecation warning new Buffer() should be replaced with one of:

  • Buffer.alloc()
  • Buffer.allocUnsafe() or
  • Buffer.from()

Another option in order to avoid this issue would be using the safe-buffer package instead.

You can also try (when using yarn..):

yarn global add yarn

as mentioned here: Link

Another suggestion from the comments (thx to gkiely): self-update

Note: self-update is not available. See policies for enforcing versions within a project

In order to update your version of Yarn, run

curl --compressed -o- -L https://yarnpkg.com/install.sh | bash

How can I kill all sessions connecting to my oracle database?

If Oracle is running in Unix /Linux then we can grep for all client connections and kill it

grep all oracle client process:

ps -ef | grep LOCAL=NO | grep -v grep | awk '{print $2}' | wc -l

Kill all oracle client process :

kill -9 ps -ef | grep LOCAL=NO | grep -v grep | awk '{print $2}'

You cannot call a method on a null-valued expression

The simple answer for this one is that you have an undeclared (null) variable. In this case it is $md5. From the comment you put this needed to be declared elsewhere in your code

$md5 = new-object -TypeName System.Security.Cryptography.MD5CryptoServiceProvider

The error was because you are trying to execute a method that does not exist.

PS C:\Users\Matt> $md5 | gm


   TypeName: System.Security.Cryptography.MD5CryptoServiceProvider

Name                       MemberType Definition                                                                                                                            
----                       ---------- ----------                                                                                                                            
Clear                      Method     void Clear()                                                                                                                          
ComputeHash                Method     byte[] ComputeHash(System.IO.Stream inputStream), byte[] ComputeHash(byte[] buffer), byte[] ComputeHash(byte[] buffer, int offset, ...

The .ComputeHash() of $md5.ComputeHash() was the null valued expression. Typing in gibberish would create the same effect.

PS C:\Users\Matt> $bagel.MakeMeABagel()
You cannot call a method on a null-valued expression.
At line:1 char:1
+ $bagel.MakeMeABagel()
+ ~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull

PowerShell by default allows this to happen as defined its StrictMode

When Set-StrictMode is off, uninitialized variables (Version 1) are assumed to have a value of 0 (zero) or $Null, depending on type. References to non-existent properties return $Null, and the results of function syntax that is not valid vary with the error. Unnamed variables are not permitted.

Does not contain a static 'main' method suitable for an entry point

I was looking at this issue as well, and in my case the solution was too easy. I added a new empty project to the solution. The newly added project is automatically set as a console application. But since the project added was a 'empty' project, no Program.cs existed in that new project. (As expected)

All I needed to do was change the output type of the project properties to Class library

How do I get current date/time on the Windows command line in a suitable format for usage in a file/folder name?

Two more ways that do not depend on the time settings (both taken from :How get data/time independent from localization:). And both also get the day of the week and none of them requires admin permissions!:

  1. MAKECAB - will work on EVERY Windows system (fast, but creates a small temp file) (the foxidrive script):

    @echo off
    pushd "%temp%"
    makecab /D RptFileName=~.rpt /D InfFileName=~.inf /f nul >nul
    for /f "tokens=3-7" %%a in ('find /i "makecab"^<~.rpt') do (
       set "current-date=%%e-%%b-%%c"
       set "current-time=%%d"
       set "weekday=%%a"
    )
    del ~.*
    popd
    echo %weekday% %current-date% %current-time%
    pause
    

    More information about get-date function.

  2. ROBOCOPY - it's not native command for Windows XP and Windows Server 2003, but it can be downloaded from microsoft site. But is built-in in everything from Windows Vista and above:

    @echo off
    setlocal
    for /f "skip=8 tokens=2,3,4,5,6,7,8 delims=: " %%D in ('robocopy /l * \ \ /ns /nc /ndl /nfl /np /njh /XF * /XD *') do (
     set "dow=%%D"
     set "month=%%E"
     set "day=%%F"
     set "HH=%%G"
     set "MM=%%H"
     set "SS=%%I"
     set "year=%%J"
    )
    
    echo Day of the week: %dow%
    echo Day of the month : %day%
    echo Month : %month%
    echo hour : %HH%
    echo minutes : %MM%
    echo seconds : %SS%
    echo year : %year%
    endlocal
    

    And three more ways that uses other Windows script languages. They will give you more flexibility e.g. you can get week of the year, time in milliseconds and so on.

  3. JScript/batch hybrid (need to be saved as .bat). JScript is available on every system form NT and above, as a part of Windows Script Host (though can be disabled through the registry it's a rare case):

    @if (@X)==(@Y) @end /* ---Harmless hybrid line that begins a JScript comment
    
    @echo off
    cscript //E:JScript //nologo "%~f0"
    exit /b 0
    *------------------------------------------------------------------------------*/
    
    function GetCurrentDate() {
            // Today date time which will used to set as default date.
            var todayDate = new Date();
            todayDate = todayDate.getFullYear() + "-" +
                           ("0" + (todayDate.getMonth() + 1)).slice(-2) + "-" +
                           ("0" + todayDate.getDate()).slice(-2) + " " + ("0" + todayDate.getHours()).slice(-2) + ":" +
                           ("0" + todayDate.getMinutes()).slice(-2);
    
            return todayDate;
        }
    
    WScript.Echo(GetCurrentDate());
    
  4. VSCRIPT/BATCH hybrid (Is it possible to embed and execute VBScript within a batch file without using a temporary file?) same case as JScript, but hybridization is not so perfect:

    :sub echo(str) :end sub
    echo off
    '>nul 2>&1|| copy /Y %windir%\System32\doskey.exe %windir%\System32\'.exe >nul
    '& echo current date:
    '& cscript /nologo /E:vbscript "%~f0"
    '& exit /b
    
    '0 = vbGeneralDate - Default. Returns date: mm/dd/yy and time if specified: hh:mm:ss PM/AM.
    '1 = vbLongDate - Returns date: weekday, monthname, year
    '2 = vbShortDate - Returns date: mm/dd/yy
    '3 = vbLongTime - Returns time: hh:mm:ss PM/AM
    '4 = vbShortTime - Return time: hh:mm
    
    WScript.echo  Replace(FormatDateTime(Date,1),", ","-")
    
  5. PowerShell - can be installed on every machine that has .NET - download from Microsoft (v1, v2, v3 (only for Windows 7 and above)). It is installed by default on everything from Windows 7/Windows Server 2008 and above:

    C:\> powershell get-date -format "{dd-MMM-yyyy HH:mm}"
    

    To use it from a batch file:

    for /f "delims=" %%# in ('powershell get-date -format "{dd-MMM-yyyy HH:mm}"') do @set _date=%%#
    
  6. Self-compiled jscript.net/batch (never seen a Windows machine without .NET, so I think this is a pretty portable):

    @if (@X)==(@Y) @end /****** silent line that start JScript comment ******
    
    @echo off
    ::::::::::::::::::::::::::::::::::::
    :::       Compile the script    ::::
    ::::::::::::::::::::::::::::::::::::
    setlocal
    if exist "%~n0.exe" goto :skip_compilation
    
    set "frm=%SystemRoot%\Microsoft.NET\Framework\"
    
    :: Searching the latest installed .NET framework
    for /f "tokens=* delims=" %%v in ('dir /b /s /a:d /o:-n "%SystemRoot%\Microsoft.NET\Framework\v*"') do (
        if exist "%%v\jsc.exe" (
            rem :: the javascript.net compiler
            set "jsc=%%~dpsnfxv\jsc.exe"
            goto :break_loop
        )
    )
    echo jsc.exe not found && exit /b 0
    :break_loop
    
    
    call %jsc% /nologo /out:"%~n0.exe" "%~dpsfnx0"
    ::::::::::::::::::::::::::::::::::::
    :::       End of compilation    ::::
    ::::::::::::::::::::::::::::::::::::
    :skip_compilation
    
    "%~n0.exe"
    
    exit /b 0
    
    
    ****** End of JScript comment ******/
    import System;
    import System.IO;
    
    var dt=DateTime.Now;
    Console.WriteLine(dt.ToString("yyyy-MM-dd hh:mm:ss"));
    
  7. Logman This cannot get the year and day of the week. It's comparatively slow and also creates a temporary file and is based on the time stamps that logman puts on its log files. It will work on everything from Windows XP and above. It probably will be never used by anybody - including me - but is one more way...

    @echo off
    setlocal
    del /q /f %temp%\timestampfile_*
    
    Logman.exe stop ts-CPU 1>nul 2>&1
    Logman.exe delete ts-CPU 1>nul 2>&1
    
    Logman.exe create counter ts-CPU  -sc 2 -v mmddhhmm -max 250 -c "\Processor(_Total)\%% Processor Time" -o %temp%\timestampfile_ >nul
    Logman.exe start ts-CPU 1>nul 2>&1
    
    Logman.exe stop ts-CPU >nul 2>&1
    Logman.exe delete ts-CPU >nul 2>&1
    for /f "tokens=2 delims=_." %%t in  ('dir /b %temp%\timestampfile_*^&del /q/f %temp%\timestampfile_*') do set timestamp=%%t
    
    echo %timestamp%
    echo MM: %timestamp:~0,2%
    echo dd: %timestamp:~2,2%
    echo hh: %timestamp:~4,2%
    echo mm: %timestamp:~6,2%
    
    endlocal
    exit /b 0
    
  8. One more way with WMIC which also gives week of the year and the day of the week, but not the milliseconds (for milliseconds check foxidrive's answer):

    for /f %%# in ('wMIC Path Win32_LocalTime Get /Format:value') do @for /f %%@ in ("%%#") do @set %%@
    echo %day%
    echo %DayOfWeek%
    echo %hour%
    echo %minute%
    echo %month%
    echo %quarter%
    echo %second%
    echo %weekinmonth%
    echo %year%
    
  9. Using TYPEPERF with some efforts to be fast and compatible with different language settings and as fast as possible:

    @echo off
    setlocal
    
    :: Check if Windows is Windows XP and use Windows XP valid counter for UDP performance
    ::if defined USERDOMAIN_roamingprofile (set "v=v4") else (set "v=")
    
    for /f "tokens=4 delims=. " %%# in ('ver') do if %%# GTR 5 (set "v=v4") else ("v=")
    set "mon="
    for /f "skip=2 delims=," %%# in ('typeperf "\UDP%v%\*" -si 0 -sc 1') do (
       if not defined mon (
          for /f "tokens=1-7 delims=.:/ " %%a in (%%#) do (
            set mon=%%a
            set date=%%b
            set year=%%c
            set hour=%%d
            set minute=%%e
            set sec=%%f
            set ms=%%g
          )
       )
    )
    echo %year%.%mon%.%date%
    echo %hour%:%minute%:%sec%.%ms%
    endlocal
    
  10. MSHTA allows calling JavaScript methods similar to the JScript method demonstrated in #3 above. Bear in mind that JavaScript's Date object properties involving month values are numbered from 0 to 11, not 1 to 12. So a value of 9 means October.

    <!-- : Batch portion
    
    @echo off
    setlocal
    
    for /f "delims=" %%I in ('mshta "%~f0"') do set "now.%%~I"
    
    rem Display all variables beginning with "now."
    set now.
    
    goto :EOF
    
    end batch / begin HTA -->
    
    <script>
        resizeTo(0,0)
        var fso = new ActiveXObject('Scripting.FileSystemObject').GetStandardStream(1),
            now = new Date(),
            props=['getDate','getDay','getFullYear','getHours','getMilliseconds','getMinutes',
                'getMonth','getSeconds','getTime','getTimezoneOffset','getUTCDate','getUTCDay',
                'getUTCFullYear','getUTCHours','getUTCMilliseconds','getUTCMinutes','getUTCMonth',
                'getUTCSeconds','getYear','toDateString','toGMTString','toLocaleDateString',
                'toLocaleTimeString','toString','toTimeString','toUTCString','valueOf'],
            output = [];
    
        for (var i in props) {output.push(props[i] + '()=' + now[props[i]]())}
        close(fso.Write(output.join('\n')));
    </script>
    

How to get the latest file in a folder?

I have tried to use the above suggestions and my program crashed, than I figured out the file I'm trying to identify was used and when trying to use 'os.path.getctime' it crashed. what finally worked for me was:

    files_before = glob.glob(os.path.join(my_path,'*'))
    **code where new file is created**
    new_file = set(files_before).symmetric_difference(set(glob.glob(os.path.join(my_path,'*'))))

this codes gets the uncommon object between the two sets of file lists its not the most elegant, and if multiple files are created at the same time it would probably won't be stable

How to set default value for HTML select?

You could use...

<option <?= ($temp == $value) ? "SELECTED" : "" ?> >$value</opton>

Edit: I thought I was looking at PHP questions... Sorry.

How to get numeric value from a prompt box?

You have to use parseInt() to convert

For eg.

  var z = parseInt(x) + parseInt(y);

use parseFloat() if you want to handle float value.

How to get a random value from dictionary?

Since the original post wanted the pair:

import random
d = {'VENEZUELA':'CARACAS', 'CANADA':'TORONTO'}
country, capital = random.choice(list(d.items()))

(python 3 style)

Tool to Unminify / Decompress JavaScript

Pretty Diff will beautify (pretty print) JavaScript in a way that conforms to JSLint and JSHint white space algorithms.

enum - getting value of enum on string conversion

I implemented access using the following

class D(Enum):
    x = 1
    y = 2

    def __str__(self):
        return '%s' % self.value

now I can just do

print(D.x) to get 1 as result.

You can also use self.name in case you wanted to print x instead of 1.

What is the difference between encrypting and signing in asymmetric encryption?

In your scenario, you do not encrypt in the meaning of asymmetric encryption; I'd rather call it "encode".

So you encode your data into some binary representation, then you sign with your private key. If you cannot verify the signature via your public key, you know that the signed data is not generated with your private key. ("verification" meaning that the unsigned data is not meaningful)

Changing factor levels with dplyr mutate

With the forcats package from the tidyverse this is easy, too.

mutate(dat, x = fct_recode(x, "B" = "A"))

How do I install boto?

If you're on a mac, by far the simplest way to install is to use easy_install

sudo easy_install boto3

Submit form after calling e.preventDefault()

In my case there was a race, as I needed the ajax response to fill a hidden field and send the form after it's filled. I fixed it with putting e.preventDefault() into a condition.

var all_is_done=false;
$("form").submit(function(e){
  if(all_is_done==false){
   e.preventDefault();
   do_the_stuff();
  }
});
function do_the_stuf(){
  //do stuff
  all_is_done=true;
  $("form").submit();
}

Simple Android RecyclerView example

Now you need 1 adapter for all RecyclerView

  • One adapter can be used in for all RecyclerView. So NO onBindViewHolder, No onCreateViewHolder handling.
  • No code for setting adapter from Java/Kotlin class. Check sample class.
  • You can set events and custom data for every list by using Binding Adapters.

screenshot

I show here setting two different RecyclerView by 1 adapter -

activity_home.xml

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto">

    <data>

        <variable
            name="listOne"
            type="java.util.List"/>

        <variable
            name="listTwo"
            type="java.util.List"/>

        <variable
            name="onItemClickListenerOne"
            type="com.ks.nestedrecyclerbindingexample.callbacks.OnItemClickListener"/>

        <variable
            name="onItemClickListenerTwo"
            type="com.ks.nestedrecyclerbindingexample.callbacks.OnItemClickListener"/>

    </data>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <android.support.v7.widget.RecyclerView
            rvItemLayout="@{@layout/row_one}"
            rvList="@{listOne}"
            rvOnItemClick="@{onItemClickListenerOne}"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:layoutManager="android.support.v7.widget.LinearLayoutManager"
            />

        <android.support.v7.widget.RecyclerView
            rvItemLayout="@{@layout/row_two}"
            rvList="@{listTwo}"
            rvOnItemClick="@{onItemClickListenerTwo}"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:layoutManager="android.support.v7.widget.LinearLayoutManager"
            />

    </LinearLayout>

</layout>

You can see I pass list, item layout id and click listener from layout.

rvItemLayout="@{@layout/row_one}"
rvList="@{listOne}"
rvOnItemClick="@{onItemClickListenerOne}"

This custom attributes are created by BindingAdapter.

public class BindingAdapters {
    @BindingAdapter(value = {"rvItemLayout", "rvList", "rvOnItemClick"}, requireAll = false)
    public static void setRvAdapter(RecyclerView recyclerView, int rvItemLayout, List rvList, @Nullable OnItemClickListener onItemClickListener) {
        if (rvItemLayout != 0 && rvList != null && rvList.size() > 0)
            recyclerView.setAdapter(new GeneralAdapter(rvItemLayout, rvList, onItemClickListener));
    }
}

Now from Activity, you pass list, click listener like

HomeActivity.java

public class HomeActivity extends AppCompatActivity {
    ActivityHomeBinding binding;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        binding = DataBindingUtil.setContentView(this, R.layout.activity_home);
        binding.setListOne(new ArrayList()); // pass your list or set list from response of API
        binding.setListTwo(new ArrayList());
        binding.setOnItemClickListenerOne(new OnItemClickListener() {
            @Override
            public void onItemClick(View view, Object object) {
                if (object instanceof ModelParent) {
                    // TODO: your action here
                }
            }
        });
        binding.setOnItemClickListenerTwo(new OnItemClickListener() {
            @Override
            public void onItemClick(View view, Object object) {
                if (object instanceof ModelChild) {
                    // TODO: your action here  
                }
            }
        });
    }
}

You don't want read too much, directly clone/download full example on from my github repo. And try it yourself.

You can see GeneralAdapter.java in above repo.

If you have problems while setting up data binding, please see this answer.

What characters do I need to escape in XML documents?

In addition to the commonly known five characters [<, >, &, ", and '], I would also escape the vertical tab character (0x0B). It is valid UTF-8, but not valid XML 1.0, and even many libraries (including the highly portable (ANSI C) library libxml2) miss it and silently output invalid XML.

Delete all objects in a list

Here's how you delete every item from a list.

del c[:]

Here's how you delete the first two items from a list.

del c[:2]

Here's how you delete a single item from a list (a in your case), assuming c is a list.

del c[0]

How to get pixel data from a UIImage (Cocoa Touch) or CGImage (Core Graphics)?

Apple's Technical Q&A QA1509 shows the following simple approach:

CFDataRef CopyImagePixels(CGImageRef inImage)
{
    return CGDataProviderCopyData(CGImageGetDataProvider(inImage));
}

Use CFDataGetBytePtr to get to the actual bytes (and various CGImageGet* methods to understand how to interpret them).

chai test array equality doesn't work as expected

For expect, .equal will compare objects rather than their data, and in your case it is two different arrays.

Use .eql in order to deeply compare values. Check out this link.
Or you could use .deep.equal in order to simulate same as .eql.
Or in your case you might want to check .members.

For asserts you can use .deepEqual, link.

JQuery - Set Attribute value

Use an ID to uniquely identify the checkbox. Your current example is trying to select the checkbox with an id of '#chk0':

<input type="checkbox" id="chk0" name="chk0" value="true" disabled>

$('#chk0').attr("disabled", "disabled");

You'll also need to remove the attribute for disabled to enable the checkbox. Something like:

$('#chk0').removeAttr("disabled");

See the docs for removeAttr

The value XHTML for disabling/enabling an input element is as follows:

<input type="checkbox" id="chk0" name="chk0" value="true" disabled="disabled" />
<input type="checkbox" id="chk0" name="chk0" value="true" />

Note that it's the absence of the disabled attribute that makes the input element enabled.

Spring Boot: Cannot access REST Controller on localhost (404)

Try adding the following to your InventoryApp class

@SpringBootApplication
@ComponentScan(basePackageClasses = ItemInventoryController.class)
public class InventoryApp {
...

spring-boot will scan for components in packages below com.nice.application, so if your controller is in com.nice.controller you need to scan for it explicitly.

Removing viewcontrollers from navigation stack

Swift 5, Xcode 11.3

I found this approach simple by specifying which view controller(s) you want to remove from the navigation stack.

extension UINavigationController {

    func removeViewController(_ controller: UIViewController.Type) {
        if let viewController = viewControllers.first(where: { $0.isKind(of: controller.self) }) {
            viewController.removeFromParent()
        }
    }
}

Example use:

navigationController.removeViewController(YourViewController.self)

Retrieving data from a POST method in ASP.NET

You can get a form value posted to a page using code similiar to this (C#) -

string formValue;
if (!string.IsNullOrEmpty(Request.Form["txtFormValue"]))
{
  formValue= Request.Form["txtFormValue"];
}

or this (VB)

Dim formValue As String
If Not String.IsNullOrEmpty(Request.Form("txtFormValue")) Then
    formValue = Request.Form("txtFormValue")
End If

Once you have the values you need you can then construct a SQL statement and and write the data to a database.

Drop all duplicate rows across multiple columns in Python Pandas

use groupby and filter

import pandas as pd
df = pd.DataFrame({"A":["foo", "foo", "foo", "bar"], "B":[0,1,1,1], "C":["A","A","B","A"]})
df.groupby(["A", "C"]).filter(lambda df:df.shape[0] == 1)

File upload progress bar with jQuery

Kathir's answer is great as he solves that problem with just jQuery. I just wanted to make some additions to his answer to work his code with a beautiful HTML progress bar:

$.ajax({
xhr: function() {
var xhr = new window.XMLHttpRequest();

xhr.upload.addEventListener("progress", function(evt) {
  if (evt.lengthComputable) {
    var percentComplete = evt.loaded / evt.total;
    percentComplete = parseInt(percentComplete * 100);

    $('.progress-bar').width(percentComplete+'%');
    $('.progress-bar').html(percentComplete+'%');

  }
}, false);

return xhr;
},
url: posturlfile,
type: "POST",
data: JSON.stringify(fileuploaddata),
contentType: "application/json",
dataType: "json",
success: function(result) {
console.log(result);
}
});

Here is the HTML code of progress bar, I used Bootstrap 3 for the progress bar element:

<div class="progress" style="display:none;">
<div class="progress-bar progress-bar-success progress-bar-striped 
active" role="progressbar"
aria-valuemin="0" aria-valuemax="100" style="width:0%">
0%
</div>
</div>

How do I reload a page without a POSTDATA warning in Javascript?

Nikl's version doesn't pass get query parameters, I used the following modified version:

window.location.href = window.location.protocol +'//'+ window.location.host + window.location.pathname + window.location.search;

or in my case I needed to refresh the topmost page\frame, so I used the following version

window.top.location.href = window.top.location.protocol +'//'+ window.top.location.host + window.top.location.pathname + window.top.location.search;

How to parse SOAP XML?

First, we need to filter the XML so as to parse that change objects become array

//catch xml
$xmlElement = file_get_contents ('php://input');
//change become array
$Data = (array)simplexml_load_string($xmlElement);
//and see
print_r($Data);

How to remove all options from a dropdown using jQuery / JavaScript

You can either use .remove() on option elements:

.remove() : Remove the set of matched elements from the DOM.

 $('#models option').remove(); or $('#models').remove('option');

or use .empty() on select:

.empty() : Remove all child nodes of the set of matched elements from the DOM.

 $('#models').empty();

however to repopulate deleted options, you need to store the option while deleting.

You can also achieve the same using show/hide:

$("#models option").hide();

and later on to show them:

$("#models option").show();

LINQ to Entities how to update a record

//for update

(from x in dataBase.Customers
         where x.Name == "Test"
         select x).ToList().ForEach(xx => xx.Name="New Name");

//for delete

dataBase.Customers.RemoveAll(x=>x.Name=="Name");

UL has margin on the left

The <ul> element has browser inherent padding & margin by default. In your case, Use

#footer ul {
    margin: 0; /* To remove default bottom margin */ 
    padding: 0; /* To remove default left padding */
}

or a CSS browser reset ( https://cssreset.com/ ) to deal with this.

How to append strings using sprintf?

I find the following method works nicely.

sprintf(Buffer,"Hello World");
sprintf(&Buffer[strlen[Buffer]],"Good Morning");
sprintf(&Buffer[strlen[Buffer]],"Good Afternoon");

How can I iterate over the elements in Hashmap?

Need Key & Value in Iteration

Use entrySet() to iterate through Map and need to access value and key:

Map<String, Person> hm = new HashMap<String, Person>();

hm.put("A", new Person("p1"));
hm.put("B", new Person("p2"));
hm.put("C", new Person("p3"));
hm.put("D", new Person("p4"));
hm.put("E", new Person("p5"));

Set<Map.Entry<String, Person>> set = hm.entrySet();

for (Map.Entry<String, Person> me : set) {
  System.out.println("Key :"+me.getKey() +" Name : "+ me.getValue().getName()+"Age :"+me.getValue().getAge());

}

Need Key in Iteration

If you want just to iterate over keys of map you can use keySet()

for(String key: map.keySet()) {
     Person value = map.get(key); 
}

Need Value in Iteration

If you just want to iterate over values of map you can use values()

for(Person person: map.values()) {

}

Why does "npm install" rewrite package-lock.json?

Probably you should use something like this

npm ci

Instead of using npm install if you don't want to change the version of your package.

According to the official documentation, both npm install and npm ci install the dependencies which are needed for the project.

The main difference is, npm install does install the packages taking packge.json as a reference. Where in the case of npm ci, it does install the packages taking package-lock.json as a reference, making sure every time the exact package is installed.

Interactive shell using Docker Compose

This question is very interesting for me because I have problems, when I run container after execution finishes immediately exit and I fixed with -it:

docker run -it -p 3000:3000 -v /app/node_modules -v $(pwd):/app <your_container_id>

And when I must automate it with docker compose:

version: '3'
services:
    frontend:
        stdin_open: true
        tty: true
        build: 
            context: .
            dockerfile: Dockerfile.dev
        ports: 
            - "3000:3000"
        volumes: 
            - /app/node_modules
            - .:/app

This makes the trick: stdin_open: true, tty: true

This is a project generated with create-react-app

Dockerfile.dev it looks this that:

FROM node:alpine

WORKDIR '/app'

COPY package.json .
RUN npm install

COPY . . 

CMD ["npm", "run", "start"]

Hope this example will help other to run a frontend(react in example) into docker container.

Java: convert List<String> to a String

With java 1.8 stream can be used ,

import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;
List<String> list = Arrays.asList("Bill","Bob","Steve").
String str = list.stream().collect(Collectors.joining(" and "));

How to send authorization header with axios

res.setHeader('Access-Control-Allow-Headers',
            'Access-Control-Allow-Headers, Origin,OPTIONS,Accept,Authorization, X-Requested-With, Content-Type, Access-Control-Request-Method, Access-Control-Request-Headers');

Blockquote : you have to add OPTIONS & Authorization to the setHeader()

this change has fixed my problem, just give a try!

Getting Raw XML From SOAPMessage in Java

this works

 final StringWriter sw = new StringWriter();

try {
    TransformerFactory.newInstance().newTransformer().transform(
        new DOMSource(soapResponse.getSOAPPart()),
        new StreamResult(sw));
} catch (TransformerException e) {
    throw new RuntimeException(e);
}
System.out.println(sw.toString());
return sw.toString();

Run Batch File On Start-up

Another option would be to run the batch file as a service, and set the startup of the service to "Automatic" or "Automatic (Delayed Start)". Check this question for more information on how to do it, personally I like NSSM the most.

Check if an image is loaded (no errors) with jQuery

Based on my understanding of the W3C HTML Specification for the img element, you should be able to do this using a combination of the complete and naturalHeight attributes, like so:

function imgLoaded(imgElement) {
  return imgElement.complete && imgElement.naturalHeight !== 0;
}

From the spec for the complete attribute:

The IDL attribute complete must return true if any of the following conditions is true:

  • The src attribute is omitted.
  • The final task that is queued by the networking task source once the resource has been fetched has been queued.
  • The img element is completely available.
  • The img element is broken.

Otherwise, the attribute must return false.

So essentially, complete returns true if the image has either finished loading, or failed to load. Since we want only the case where the image successfully loaded we need to check the nauturalHeight attribute as well:

The IDL attributes naturalWidth and naturalHeight must return the intrinsic width and height of the image, in CSS pixels, if the image is available, or else 0.

And available is defined like so:

An img is always in one of the following states:

  • Unavailable - The user agent hasn't obtained any image data.
  • Partially available - The user agent has obtained some of the image data.
  • Completely available - The user agent has obtained all of the image data and at least the image dimensions are available.
  • Broken - The user agent has obtained all of the image data that it can, but it cannot even decode the image enough to get the image dimensions (e.g. the image is corrupted, or the format is not supported, or no data could be obtained).

When an img element is either in the partially available state or in the completely available state, it is said to be available.

So if the image is "broken" (failed to load), then it will be in the broken state, not the available state, so naturalHeight will be 0.

Therefore, checking imgElement.complete && imgElement.naturalHeight !== 0 should tell us whether the image has successfully loaded.

You can read more about this in the W3C HTML Specification for the img element, or on MDN.

How do I view 'git diff' output with my preferred diff tool/ viewer?

I have one addition to this. I like to regularly use a diff app that isn't supported as one of the default tools (e.g. kaleidoscope), via

git difftool -t

I also like to have the default diff just be the regular command line, so setting the GIT_EXTERNAL_DIFF variable isn't an option.

You can use an arbitrary diff app as a one-off with this command:

git difftool --extcmd=/usr/bin/ksdiff

It just passes the 2 files to the command you specify, so you probably don't need a wrapper either.

How do you set the startup page for debugging in an ASP.NET MVC application?

Revisiting this page and I have more information to share with others.

Debugging environment (using Visual Studio)

1a) Stephen Walter's link to set the startup page on MVC using the project properties is only applicable when you are debugging your MVC application.

1b) Right mouse click on the .aspx page in Solution Explorer and select the "Set As Start Page" behaves the same.

Note: in both the above cases, the startup page setting is only recognised by your Visual Studio Development Server. It is not recognised by your deployed server.

Deployed environment

2a) To set the startup page, assuming that you have not change any of the default routings, change the content of /Views/Home/Index.aspx to do a "Server.Transfer" or a "Response.Redirect" to your desired page.

2b) Change your default routing in your global.asax.cs to your desired page.

Are there any other options that the readers are aware of? Which of the above (including your own option) would be your preferred solution (and please share with us why)?

How to start http-server locally

To start server locally paste the below code in package.json and run npm start in command line.

"scripts": { "start": "http-server -c-1 -p 8081" },

What is the HTML5 equivalent to the align attribute in table cells?

According to the HTML5 CR, which requires continued support to “obsolete” features, too, the align=center attribute is rather tricky. Rendering rules for tables say: td elements with that attribute “are expected to center text within themselves, as if they had their 'text-align' property set to 'center' in a presentational hint, and to align descendants to the center.”

And aligning descendants is defined as so that a browser will “align only those descendants that have both their 'margin-left' and 'margin-right' properties computing to a value other than 'auto', that are over-constrained and that have one of those two margins with a used value forced to a greater value, and that do not themselves have an applicable align attribute. When multiple elements are to align a particular descendant, the most deeply nested such element is expected to override the others. Aligned elements are expected to be aligned by having the used values of their left and right margins be set accordingly.”

So it really depends on the content.

how to remove key+value from hash in javascript

You're looking for delete:

delete myhash['key2']

See the Core Javascript Guide

Stopping Excel Macro executution when pressing Esc won't work

I've found that sometimes whem I open a second Excel window and run a macro on that second window, the execution of the first one stops. I don't know why it doesn't work all the time, but you may try.

getElementsByClassName not working

If you want to do it by ClassName you could do:

<script type="text/javascript">
function hideTd(className){
    var elements;

    if (document.getElementsByClassName)
    {
        elements = document.getElementsByClassName(className);
    }
    else
    {
        var elArray = [];
        var tmp = document.getElementsByTagName(elements);  
        var regex = new RegExp("(^|\\s)" + className+ "(\\s|$)");
        for ( var i = 0; i < tmp.length; i++ ) {

            if ( regex.test(tmp[i].className) ) {
                elArray.push(tmp[i]);
            }
        }

        elements = elArray;
    }

    for(var i = 0, i < elements.length; i++) {
       if( elements[i].textContent == ''){
          elements[i].style.display = 'none';
       } 
    }

  }
</script>

Should IBOutlets be strong or weak under ARC?

I think that most important information is: Elements in xib are automatically in subviews of view. Subviews is NSArray. NSArray owns it's elements. etc have strong pointers on them. So in most cases you don't want to create another strong pointer (IBOutlet)

And with ARC you don't need to do anything in viewDidUnload

How to use Google App Engine with my own naked domain (not subdomain)?

Google does not provide an IP for us to set A record. If it would we could use naked domains.

There is another option, by setting A record to foreign web server's IP and that server could make an http redirect from e.g domain.com to www.domain.com (check out GiDNS)

javascript regex for password containing at least 8 characters, 1 number, 1 upper and 1 lowercase

Your regex only allows exactly 8 characters. Use {8,} to specify eight or more instead of {8}.

But why would you limit the allowed character range for your passwords? 8-character alphanumeric passwords can be bruteforced by my phone within minutes.

ffprobe or avprobe not found. Please install one

Compiling the last answers into one:

If you're on Windows, use chocolatey:

choco install ffmpeg

If you are on Mac, use Brew:

brew install ffmpeg

If you are on a Debian Linux distribution, use apt:

sudo apt-get install ffmpeg

And make sure Youtube-dl is updated:

youtube-dl -U

CSS Font Border?

Stroke font-character with a Less mixin

Here's a LESS mixin to generate the stroke: http://codepen.io/anon/pen/BNYGBy?editors=110

/// Stroke font-character
/// @param  {Integer} $stroke - Stroke width
/// @param  {Color}   $color  - Stroke color
/// @return {List}            - text-shadow list
.stroke(@stroke, @color) {
  @maxi: @stroke + 1;
  .i-loop (@i) when (@i > 0) {
    @maxj: @stroke + 1;
    .j-loop (@j) when (@j > 0) {
      text-shadow+: (@i - 1)*(1px)  (@j - 1)*(1px) 0 @color;
      text-shadow+: (@i - 1)*(1px)  (@j - 1)*(-1px) 0 @color;
      text-shadow+: (@i - 1)*(-1px)  (@j - 1)*(-1px) 0 @color;
      text-shadow+: (@i - 1)*(-1px)  (@j - 1)*(1px) 0 @color;
      .j-loop(@j - 1);
    }
    .j-loop (0) {}
    .j-loop(@maxj);
    .i-loop(@i - 1);
  }
  .i-loop (0) {}
  .i-loop(@maxi);
  text-shadow+: 0 0 0 @color;
}

(it's based on pixelass answer that instead uses SCSS)

How to export settings?

Often there are questions about the java settings in vsCode. This is a big question and can involve advanced user knowledge to accmplish. But there is simple way to get the existing java settings from vsCode and copy these setting for use on another PC. This post is using recent versions of vsCode and JDK in mid-December 2020.

There are several screen shots (below) that accompany this post which should provide enough information for the visual learners.

First things first, open vsCode and either open an existing java folder-file or create a new java file in vsCode. Then look at the lower right corner of vsCode (on the blue command bar). The vsCode should be displaying an icon showing the version of the Java Standard Edition ( Java SE ) being used. The version being on this PC today is JavaSE-15. (link 1)

Click on that icon (JAVASE-15) which then opens a new window named "java.configuration.runtimes". There should be two tabs below this name: User and Workspace. Below these tabs is a link named, "Edit in settings.json". Click on that link. (link 2)

Two json files should then open: Default settings and settings.json. This post only focuses on the "settings.json" file. The settings.json file shows various settings used for coding different programming languages (Python, R, and java). Near the bottom of the settings.json file shows the settings this User uses in vsCode for programming java.

These java settings are the settings that can be "backed up" - meaning these settings get copied and pasted to another PC for creating a java programming environment similar to the java programming environment on this PC. (link 3)

link 1

link 2

link 3

Adding gif image in an ImageView in android

You can display any gif image via library Fresco by Facebook:

Uri uri = Uri.parse("http://domain.com/awersome.gif");
final SimpleDraweeView draweeView = new SimpleDraweeView(context);
final LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(200, 200);

draweeView.setLayoutParams(params);
DraweeController controller = Fresco.newDraweeControllerBuilder()
        .setUri(uri)
        .setAutoPlayAnimations(true)
        .build();
draweeView.setController(controller);
//now just add draweeView to layout and enjoy

In-place type conversion of a NumPy array

You can change the array type without converting like this:

a.dtype = numpy.float32

but first you have to change all the integers to something that will be interpreted as the corresponding float. A very slow way to do this would be to use python's struct module like this:

def toi(i):
    return struct.unpack('i',struct.pack('f',float(i)))[0]

...applied to each member of your array.

But perhaps a faster way would be to utilize numpy's ctypeslib tools (which I am unfamiliar with)

- edit -

Since ctypeslib doesnt seem to work, then I would proceed with the conversion with the typical numpy.astype method, but proceed in block sizes that are within your memory limits:

a[0:10000] = a[0:10000].astype('float32').view('int32')

...then change the dtype when done.

Here is a function that accomplishes the task for any compatible dtypes (only works for dtypes with same-sized items) and handles arbitrarily-shaped arrays with user-control over block size:

import numpy

def astype_inplace(a, dtype, blocksize=10000):
    oldtype = a.dtype
    newtype = numpy.dtype(dtype)
    assert oldtype.itemsize is newtype.itemsize
    for idx in xrange(0, a.size, blocksize):
        a.flat[idx:idx + blocksize] = \
            a.flat[idx:idx + blocksize].astype(newtype).view(oldtype)
    a.dtype = newtype

a = numpy.random.randint(100,size=100).reshape((10,10))
print a
astype_inplace(a, 'float32')
print a

Twitter Bootstrap Tabs: Go to Specific Tab on Page Reload or Hyperlink

you could trigger a click event on the corresponding tab link:

$(document).ready(function(){

  if(window.location.hash != "") {
      $('a[href="' + window.location.hash + '"]').click()
  }

});

Difference between filter and filter_by in SQLAlchemy

It is a syntax sugar for faster query writing. Its implementation in pseudocode:

def filter_by(self, **kwargs):
    return self.filter(sql.and_(**kwargs))

For AND you can simply write:

session.query(db.users).filter_by(name='Joe', surname='Dodson')

btw

session.query(db.users).filter(or_(db.users.name=='Ryan', db.users.country=='England'))

can be written as

session.query(db.users).filter((db.users.name=='Ryan') | (db.users.country=='England'))

Also you can get object directly by PK via get method:

Users.query.get(123)
# And even by a composite PK
Users.query.get(123, 321)

When using get case its important that object can be returned without database request from identity map which can be used as cache(associated with transaction)

Android Studio: Can't start Git

I had the same problem, this is how I fixed it:

I use windows...

Go to

C:\Users\<username>\AppData\Local\GitHub\PortableGit_c2ba306e536fdf878271f7fe636a147ff37326ad\bin

So in my Account I had this

C:\Users\victor\AppData\Local\GitHub\PortableGit_c2ba306e536fdf878271f7fe636a147ff37326ad\bin

Make sure you find the git.exe

Then go to the VCS window(Settings --> Version Control---> Git), and paste the PATH and append git.exe at the end

So you shall have this

C:\Users\<username>\AppData\Local\GitHub\PortableGit_c2ba306e536fdf878271f7fe636a147ff37326ad\bin\git.exe 

Then click test to verify if git is working well.

Can an int be null in Java?

In Java, int is a primitive type and it is not considered an object. Only objects can have a null value. So the answer to your question is no, it can't be null. But it's not that simple, because there are objects that represent most primitive types.

The class Integer represents an int value, but it can hold a null value. Depending on your check method, you could be returning an int or an Integer.

This behavior is different from some more purely object oriented languages like Ruby, where even "primitive" things like ints are considered objects.

Can you blur the content beneath/behind a div?

you can do this with css3, this blurs the whole element

div (or whatever element) {
  -webkit-filter: blur(5px);
  -moz-filter: blur(5px);
  -o-filter: blur(5px);
  -ms-filter: blur(5px);
  filter: blur(5px);
}

Fiddle: http://jsfiddle.net/H4DU4/

Check if a row exists using old mysql_* API

This ought to do the trick: just limit the result to 1 row; if a row comes back the $lectureName is Assigned, otherwise it's Available.

function checkLectureStatus($lectureName)
{
    $con = connectvar();
    mysql_select_db("mydatabase", $con);
    $result = mysql_query(
        "SELECT * FROM preditors_assigned WHERE lecture_name='$lectureName' LIMIT 1");

    if(mysql_fetch_array($result) !== false)
        return 'Assigned';
    return 'Available';
}

How can I mock requests and the response?

Here is what worked for me:

import mock
@mock.patch('requests.get', mock.Mock(side_effect = lambda k:{'aurl': 'a response', 'burl' : 'b response'}.get(k, 'unhandled request %s'%k)))

The EntityManager is closed

// first need to reset current manager
$em->resetManager();
// and then get new
$em = $this->getContainer()->get("doctrine");
// or in this way, depending of your environment:
$em = $this->getDoctrine();

Making macOS Installer Packages which are Developer ID ready

A +1 to accepted answer:

Destination Selection in Installer

If domain (a.k.a destination) selection is desired between user domain and system domain then rather than trying <domains enable_anywhere="true"> use following:

<domains enable_currentUserHome="true" enable_localSystem="true"/>

enable_currentUserHome installs application app under ~/Applications/ and enable_localSystem allows the application to be installed under /Application

I've tried this in El Capitan 10.11.6 (15G1217) and it seems to be working perfectly fine in 1 dev machine and 2 different VMs I tried.

What does asterisk * mean in Python?

All of the above answers were perfectly clear and complete, but just for the record I'd like to confirm that the meaning of * and ** in python has absolutely no similarity with the meaning of similar-looking operators in C.

They are called the argument-unpacking and keyword-argument-unpacking operators.

pandas read_csv and filter columns with usecols

This code achieves what you want --- also its weird and certainly buggy:

I observed that it works when:

a) you specify the index_col rel. to the number of columns you really use -- so its three columns in this example, not four (you drop dummy and start counting from then onwards)

b) same for parse_dates

c) not so for usecols ;) for obvious reasons

d) here I adapted the names to mirror this behaviour

import pandas as pd
from StringIO import StringIO

csv = """dummy,date,loc,x
bar,20090101,a,1
bar,20090102,a,3
bar,20090103,a,5
bar,20090101,b,1
bar,20090102,b,3
bar,20090103,b,5
"""

df = pd.read_csv(StringIO(csv),
        index_col=[0,1],
        usecols=[1,2,3], 
        parse_dates=[0],
        header=0,
        names=["date", "loc", "", "x"])

print df

which prints

                x
date       loc   
2009-01-01 a    1
2009-01-02 a    3
2009-01-03 a    5
2009-01-01 b    1
2009-01-02 b    3
2009-01-03 b    5

What is NODE_ENV and how to use it in Express?

I assume the original question included how does Express use this environment variable.

Express uses NODE_ENV to alter its own default behavior. For example, in development mode, the default error handler will send back a stacktrace to the browser. In production mode, the response is simply Internal Server Error, to avoid leaking implementation details to the world.

div background color, to change onhover

simply try "hover" property of CSS. eg:

<html>
<head>
    <style>
        div
        {
            height:100px;
            width:100px;
            border:2px solid red;
        }
        div:hover
        {
            background-color:yellow;
        }
    </style>
</head>
<body>
            <a href="#">
                      <div id="ab">
                                <p> hello there </p>
                      </div>
            </a>
</body>

i hope this will help

Setting up Vim for Python

Put the following in your .vimrc

autocmd BufRead *.py set smartindent cinwords=if,elif,else,for,while,try,except,finally,def,class
autocmd BufRead *.py set nocindent
autocmd BufWritePre *.py normal m`:%s/\s\+$//e ``
filetype plugin indent on

See also the detailed instructions

I personally use JetBrain's PyCharm with the IdeaVIM plugin when doing anything complex, for simple editing the additions to .vimrc seem sufficient.

Uncaught TypeError: Cannot read property 'split' of undefined

ogdate is itself a string, why are you trying to access it's value property that it doesn't have ?

console.log(og_date.split('-'));

JSFiddle

Checkbox angular material checked by default

You can either set with ngModel either with [checked] attribute. ngModel binded property should be set to 'true':

1.

  <mat-checkbox class = "example-margin" [(ngModel)] = "myModel"> 
    <label>Printer </label> 
  </mat-checkbox>

2.

<mat-checkbox [checked]= "myModel" class = "example-margin" > 
    <label>Printer </label> 
</mat-checkbox>

3.

<mat-checkbox [ngModel]="myModel" class="example-margin">
    <label>Printer </label> 
</mat-checkbox>

DEMO

Get random item from array

echo $items[array_rand($items)];

array_rand()

Pandas read_sql with parameters

The read_sql docs say this params argument can be a list, tuple or dict (see docs).

To pass the values in the sql query, there are different syntaxes possible: ?, :1, :name, %s, %(name)s (see PEP249).
But not all of these possibilities are supported by all database drivers, which syntax is supported depends on the driver you are using (psycopg2 in your case I suppose).

In your second case, when using a dict, you are using 'named arguments', and according to the psycopg2 documentation, they support the %(name)s style (and so not the :name I suppose), see http://initd.org/psycopg/docs/usage.html#query-parameters.
So using that style should work:

df = psql.read_sql(('select "Timestamp","Value" from "MyTable" '
                     'where "Timestamp" BETWEEN %(dstart)s AND %(dfinish)s'),
                   db,params={"dstart":datetime(2014,6,24,16,0),"dfinish":datetime(2014,6,24,17,0)},
                   index_col=['Timestamp'])

If my interface must return Task what is the best way to have a no-operation implementation?

When you must return specified type:

Task.FromResult<MyClass>(null);

Eclipse, regular expression search and replace

Yes, ( ) captures a group. You can use it again with $i where i is the i'th capture group.

So:

search: (\w+\.someMethod\(\))

replace: ((TypeName)$1)

Hint: Ctrl + Space in the textboxes gives you all kinds of suggestions for regular expression writing.

Run all SQL files in a directory

I wrote an open source utility in C# that allows you to drag and drop many SQL files and start running them against a database.

The utility has the following features:

  • Drag And Drop script files
  • Run a directory of script files
  • Sql Script out put messages during execution
  • Script passed or failed that are colored green and red (yellow for running)
  • Stop on error option
  • Open script on error option
  • Run report with time taken for each script
  • Total duration time
  • Test DB connection
  • Asynchronus
  • .Net 4 & tested with SQL 2008
  • Single exe file
  • Kill connection at anytime

How to provide a file download from a JSF backing bean?

Introduction

You can get everything through ExternalContext. In JSF 1.x, you can get the raw HttpServletResponse object by ExternalContext#getResponse(). In JSF 2.x, you can use the bunch of new delegate methods like ExternalContext#getResponseOutputStream() without the need to grab the HttpServletResponse from under the JSF hoods.

On the response, you should set the Content-Type header so that the client knows which application to associate with the provided file. And, you should set the Content-Length header so that the client can calculate the download progress, otherwise it will be unknown. And, you should set the Content-Disposition header to attachment if you want a Save As dialog, otherwise the client will attempt to display it inline. Finally just write the file content to the response output stream.

Most important part is to call FacesContext#responseComplete() to inform JSF that it should not perform navigation and rendering after you've written the file to the response, otherwise the end of the response will be polluted with the HTML content of the page, or in older JSF versions, you will get an IllegalStateException with a message like getoutputstream() has already been called for this response when the JSF implementation calls getWriter() to render HTML.

Turn off ajax / don't use remote command!

You only need to make sure that the action method is not called by an ajax request, but that it is called by a normal request as you fire with <h:commandLink> and <h:commandButton>. Ajax requests and remote commands are handled by JavaScript which in turn has, due to security reasons, no facilities to force a Save As dialogue with the content of the ajax response.

In case you're using e.g. PrimeFaces <p:commandXxx>, then you need to make sure that you explicitly turn off ajax via ajax="false" attribute. In case you're using ICEfaces, then you need to nest a <f:ajax disabled="true" /> in the command component.

Generic JSF 2.x example

public void download() throws IOException {
    FacesContext fc = FacesContext.getCurrentInstance();
    ExternalContext ec = fc.getExternalContext();

    ec.responseReset(); // Some JSF component library or some Filter might have set some headers in the buffer beforehand. We want to get rid of them, else it may collide.
    ec.setResponseContentType(contentType); // Check http://www.iana.org/assignments/media-types for all types. Use if necessary ExternalContext#getMimeType() for auto-detection based on filename.
    ec.setResponseContentLength(contentLength); // Set it with the file size. This header is optional. It will work if it's omitted, but the download progress will be unknown.
    ec.setResponseHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\""); // The Save As popup magic is done here. You can give it any file name you want, this only won't work in MSIE, it will use current request URL as file name instead.

    OutputStream output = ec.getResponseOutputStream();
    // Now you can write the InputStream of the file to the above OutputStream the usual way.
    // ...

    fc.responseComplete(); // Important! Otherwise JSF will attempt to render the response which obviously will fail since it's already written with a file and closed.
}

Generic JSF 1.x example

public void download() throws IOException {
    FacesContext fc = FacesContext.getCurrentInstance();
    HttpServletResponse response = (HttpServletResponse) fc.getExternalContext().getResponse();

    response.reset(); // Some JSF component library or some Filter might have set some headers in the buffer beforehand. We want to get rid of them, else it may collide.
    response.setContentType(contentType); // Check http://www.iana.org/assignments/media-types for all types. Use if necessary ServletContext#getMimeType() for auto-detection based on filename.
    response.setContentLength(contentLength); // Set it with the file size. This header is optional. It will work if it's omitted, but the download progress will be unknown.
    response.setHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\""); // The Save As popup magic is done here. You can give it any file name you want, this only won't work in MSIE, it will use current request URL as file name instead.

    OutputStream output = response.getOutputStream();
    // Now you can write the InputStream of the file to the above OutputStream the usual way.
    // ...

    fc.responseComplete(); // Important! Otherwise JSF will attempt to render the response which obviously will fail since it's already written with a file and closed.
}

Common static file example

In case you need to stream a static file from the local disk file system, substitute the code as below:

File file = new File("/path/to/file.ext");
String fileName = file.getName();
String contentType = ec.getMimeType(fileName); // JSF 1.x: ((ServletContext) ec.getContext()).getMimeType(fileName);
int contentLength = (int) file.length();

// ...

Files.copy(file.toPath(), output);

Common dynamic file example

In case you need to stream a dynamically generated file, such as PDF or XLS, then simply provide output there where the API being used expects an OutputStream.

E.g. iText PDF:

String fileName = "dynamic.pdf";
String contentType = "application/pdf";

// ...

Document document = new Document();
PdfWriter writer = PdfWriter.getInstance(document, output);
document.open();
// Build PDF content here.
document.close();

E.g. Apache POI HSSF:

String fileName = "dynamic.xls";
String contentType = "application/vnd.ms-excel";

// ...

HSSFWorkbook workbook = new HSSFWorkbook();
// Build XLS content here.
workbook.write(output);
workbook.close();

Note that you cannot set the content length here. So you need to remove the line to set response content length. This is technically no problem, the only disadvantage is that the enduser will be presented an unknown download progress. In case this is important, then you really need to write to a local (temporary) file first and then provide it as shown in previous chapter.

Utility method

If you're using JSF utility library OmniFaces, then you can use one of the three convenient Faces#sendFile() methods taking either a File, or an InputStream, or a byte[], and specifying whether the file should be downloaded as an attachment (true) or inline (false).

public void download() throws IOException {
    Faces.sendFile(file, true);
}

Yes, this code is complete as-is. You don't need to invoke responseComplete() and so on yourself. This method also properly deals with IE-specific headers and UTF-8 filenames. You can find source code here.

How to specify the bottom border of a <tr>?

Try the following instead:

<html>
 <head>
  <title>Table row styling</title>
  <style type="text/css">
    .bb td, .bb th {
     border-bottom: 1px solid black !important;
    }
  </style>
 </head>
 <body>
  <table>
    <tr class="bb">
      <td>This</td>
      <td>should</td>
      <td>work</td>
    </tr>
  </table>
 </body>
</html>

Function to check if a string is a date

I use this function as a parameter to the PHP filter_var function.

  • It checks for dates in yyyy-mm-dd hh:mm:ss format
  • It rejects dates that match the pattern but still invalid (e.g. Apr 31)

function filter_mydate($s) {
    if (preg_match('@^(\d\d\d\d)-(\d\d)-(\d\d) (\d\d):(\d\d):(\d\d)$@', $s, $m) == false) {
        return false;
    }
    if (checkdate($m[2], $m[3], $m[1]) == false || $m[4] >= 24 || $m[5] >= 60 || $m[6] >= 60) {
        return false;
    }
    return $s;
}

Python - Using regex to find multiple matches and print them out

Instead of using re.search use re.findall it will return you all matches in a List. Or you could also use re.finditer (which i like most to use) it will return an Iterator Object and you can just use it to iterate over all found matches.

line = 'bla bla bla<form>Form 1</form> some text...<form>Form 2</form> more text?'
for match in re.finditer('<form>(.*?)</form>', line, re.S):
    print match.group(1)

[INSTALL_FAILED_NO_MATCHING_ABIS: Failed to extract native libraries, res=-113]

After some time i investigate and understand that path were located my libs is right. I just need to add folders for different architectures:

  • ARM EABI v7a System Image

  • Intel x86 Atom System Image

  • MIPS System Image

  • Google APIs

JSON character encoding

Also, you can use spring annotation RequestMapping above controller class for receveing application/json;utf-8 in all responses

@Controller
@RequestMapping(produces = {"application/json; charset=UTF-8","*/*;charset=UTF-8"})
public class MyController{
 ...
}

How to change angular port from 4200 to any other

Changing nodel_modules/angular-cli/commands/server.js is a bad idea as it will be updated when you install new version of angular-cli. Instead you should specify ng serve --port 5000 in package.json like this:

"scripts": {
    "start": "ng serve --port 5000"
}

You can also specify host with --host 127.0.0.1

jQuery remove selected option from this

$('#some_select_box option:selected').remove();

Left align block of equations

You can use \begin{flalign}, like the example bellow:

\begin{flalign}
    &f(x) = -1.25x^{2} + 1.5x&
\end{flalign}

What are the most widely used C++ vector/matrix math/linear algebra libraries, and their cost and benefit tradeoffs?

I'll add vote for Eigen: I ported a lot of code (3D geometry, linear algebra and differential equations) from different libraries to this one - improving both performance and code readability in almost all cases.

One advantage that wasn't mentioned: it's very easy to use SSE with Eigen, which significantly improves performance of 2D-3D operations (where everything can be padded to 128 bits).

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use

This solution is for windows:

  1. Open command prompt in Administrator Mode.
  2. Goto path: C:\Program Files\MySQL\MySQL Server 5.6\bin
  3. Run below command: mysqldump -h 127.0.01 -u root -proot db table1 table2 > result.sql

How to delete a record by id in Flask-SQLAlchemy

Just want to share another option:

# mark two objects to be deleted
session.delete(obj1)
session.delete(obj2)

# commit (or flush)
session.commit()

http://docs.sqlalchemy.org/en/latest/orm/session_basics.html#deleting

In this example, the following codes shall works fine:

obj = User.query.filter_by(id=123).one()
session.delete(obj)
session.commit()

How can I get client information such as OS and browser

Your best bet is User-Agent header. You can get it like this in JSP or Servlet,

String userAgent = request.getHeader("User-Agent");

The header looks like this,

User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.0.13) Gecko/2009073021 Firefox/3.0.13

It provides detailed information on browser. However, it's pretty much free format so it's very hard to decipher every single one. You just need to figure out which browsers you will support and write parser for each one. When you try to identify the version of browser, always check newer version first. For example, IE6 user-agent may contain IE5 for backward compatibility. If you check IE5 first, IE6 will be categorized as IE5 also.

You can get a full list of all user-agent values from this web site,

http://www.user-agents.org/

With User-Agent, you can tell the exact version of the browser. You can get a pretty good idea on OS but you may not be able to distinguish between different versions of the same OS, for example, Windows NT and 2000 may use same User-Agent.

There is nothing about resolution. However, you can get this with Javascript on an AJAX call.

Verify a certificate chain using openssl verify

I've had to do a verification of a letsencrypt certificate and I did it like this:

  1. Download the root-cert and the intermediate-cert from the letsencrypt chain of trust.
  2. Issue this command:

    $ openssl verify -CAfile letsencrypt-root-cert/isrgrootx1.pem.txt -untrusted letsencrypt-intermediate-cert/letsencryptauthorityx3.pem.txt /etc/letsencrypt/live/sitename.tld/cert.pem 
    /etc/letsencrypt/live/sitename.tld/cert.pem: OK
    

How does += (plus equal) work?

1) 1 += 2 // equals ?

That is syntactically invalid. The left side must be a variable. For example.

var mynum = 1;
mynum += 2;
// now mynum is 3.

mynum += 2; is just a short form for mynum = mynum + 2;

2)

var data = [1,2,3,4,5];
var sum = 0;
data.forEach(function(value) {
    sum += value; 
});

Sum is now 15. Unrolling the forEach we have:

var sum = 0;
sum += 1; // sum is 1
sum += 2; // sum is 3
sum += 3; // sum is 6
sum += 4; // sum is 10
sum += 5; // sum is 15

How can I remove an element from a list?

How about this? Again, using indices

> m <- c(1:5)
> m
[1] 1 2 3 4 5

> m[1:length(m)-1]
[1] 1 2 3 4

or

> m[-(length(m))]
[1] 1 2 3 4

TypeError: cannot perform reduce with flexible type

When your are trying to apply prod on string type of value like:

['-214' '-153' '-58' ..., '36' '191' '-37']

you will get the error.

Solution: Append only integer value like [1,2,3], and you will get your expected output.

If the value is in string format before appending then, in the array you can convert the type into int type and store it in a list.

Is it possible to use raw SQL within a Spring Repository

It is also possible to use Spring Data JDBC repository, which is a community project built on top of Spring Data Commons to access to databases with raw SQL, without using JPA.

It is less powerful than Spring Data JPA, but if you want lightweight solution for simple projects without using a an ORM like Hibernate, that a solution worth to try.

Javascript get the text value of a column from a particular row of an html table

in case if your table has tbody

let tbl = document.getElementById("tbl").getElementsByTagName('tbody')[0];
console.log(tbl.rows[0].cells[0].innerHTML)

Serializing PHP object to JSON


edit: it's currently 2016-09-24, and PHP 5.4 has been released 2012-03-01, and support has ended 2015-09-01. Still, this answer seems to gain upvotes. If you're still using PHP < 5.4, your are creating a security risk and endagering your project. If you have no compelling reasons to stay at <5.4, or even already use version >= 5.4, do not use this answer, and just use PHP>= 5.4 (or, you know, a recent one) and implement the JsonSerializable interface


You would define a function, for instance named getJsonData();, which would return either an array, stdClass object, or some other object with visible parameters rather then private/protected ones, and do a json_encode($data->getJsonData());. In essence, implement the function from 5.4, but call it by hand.

Something like this would work, as get_object_vars() is called from inside the class, having access to private/protected variables:

function getJsonData(){
    $var = get_object_vars($this);
    foreach ($var as &$value) {
        if (is_object($value) && method_exists($value,'getJsonData')) {
            $value = $value->getJsonData();
        }
    }
    return $var;
}

Converting a float to a string without rounding it

Other answers already pointed out that the representation of floating numbers is a thorny issue, to say the least.

Since you don't give enough context in your question, I cannot know if the decimal module can be useful for your needs:

http://docs.python.org/library/decimal.html

Among other things you can explicitly specify the precision that you wish to obtain (from the docs):

>>> getcontext().prec = 6
>>> Decimal('3.0')
Decimal('3.0')
>>> Decimal('3.1415926535')
Decimal('3.1415926535')
>>> Decimal('3.1415926535') + Decimal('2.7182818285')
Decimal('5.85987')
>>> getcontext().rounding = ROUND_UP
>>> Decimal('3.1415926535') + Decimal('2.7182818285')
Decimal('5.85988')

A simple example from my prompt (python 2.6):

>>> import decimal
>>> a = decimal.Decimal('10.000000001')
>>> a
Decimal('10.000000001')
>>> print a
10.000000001
>>> b = decimal.Decimal('10.00000000000000000000000000900000002')
>>> print b
10.00000000000000000000000000900000002
>>> print str(b)
10.00000000000000000000000000900000002
>>> len(str(b/decimal.Decimal('3.0')))
29

Maybe this can help? decimal is in python stdlib since 2.4, with additions in python 2.6.

Hope this helps, Francesco

How to Resize image in Swift?

For Swift 5.0 and iOS 12

extension UIImage {
    func imageResized(to size: CGSize) -> UIImage {
        return UIGraphicsImageRenderer(size: size).image { _ in
            draw(in: CGRect(origin: .zero, size: size))
        }
    }
}

use:

let image = #imageLiteral(resourceName: "ic_search")
cell!.search.image = image.imageResized(to: cell!.search.frame.size)

How can I get the behavior of GNU's readlink -f on a Mac?

Implementation

  1. Install brew

Follow the instructions at https://brew.sh/

  1. Install the coreutils package

brew install coreutils

  1. Create an Alias

You can place your alias in ~/.bashrc, ~/.bash_profile, or wherever you are used to keeping your bash aliases. I personally keep mine in ~/.bashrc

alias readlink=greadlink

You can create similar aliases for other coreutils such as gmv, gdu, gdf, and so on. But beware that the GNU behavior on a mac machine may be confusing to others used to working with native coreutils, or may behave in unexpected ways on your mac system.

Explanation

coreutils is a brew package that installs GNU/Linux core utilities which correspond to the Mac OSX implementation of them so that you can use those

You may find programs or utilties on your mac osx system which seem similar to Linux coreutils ("Core Utilities") yet they differ in some ways (such as having different flags).

This is because the Mac OSX implementation of these tools are different. To get the original GNU/Linux-like behavior you can install the coreutils package via the brew package management system.

This will install corresponding core utilities, prefixed by g. E.g. for readlink, you will find a corresponding greadlink program.

In order to make readlink perform like the GNU readlink (greadlink) implementation, you can make a simple alias after you install coreutils.

Powershell remoting with ip-address as target

Try doing this:

Set-Item WSMan:\localhost\Client\TrustedHosts -Value "*" -Force

How to clear all input fields in bootstrap modal when clicking data-dismiss button?

This is helpfull, its work for me..

$('.bd-example-modal-sm').on('hidden.bs.modal', function () { 
      $(this).find("select").val('').end(); // Clear dropdown content
      $("ul").empty();   // Clear li content 
});

What is the main difference between PATCH and PUT request?

put:
If I want to update my first name, then I send a put request:

{ "first": "Nazmul", "last": "hasan" } 

But here is a problem with using put request: When I want to send put request I have to send all two parameters that is first and last (whereas I only need to update first) so it is mandatory to send them all again with put request.

patch:
patch request, on the other hand, says: only specify the data which you need to update and it won't be affecting or changing other data.
So no need to send all values again. Do I only need to change first name? Well, It only suffices to specify first in patch request.

Creating an instance using the class name and calling constructor

If class has only one empty constructor (like Activity or Fragment etc, android classes):

Class<?> myClass = Class.forName("com.example.MyClass");    
Constructor<?> constructor = myClass.getConstructors()[0];

How can I count the occurrences of a string within a file?

I'm taking some guesses here, because I don't quite understand what you're asking.

I think that what you want is a count of the number of lines on which the pattern 'echo' appears in the given file.

I've pasted your sample text into a file called 6741967.

First, grep finds the matches:

james@Brindle:tmp$grep echo 6741967 
    echo "Preparing to add a new user..."
echo "1. Add user"
echo "2. Exit"
echo "Enter your choice: "

Second, use wc -l to count the lines

james@Brindle:tmp$grep echo 6741967  | wc -l
       4

Java compile error: "reached end of file while parsing }"

It happens when you don't properly close the code block:

if (condition){
  // your code goes here*
  { // This doesn't close the code block

Correct way:

if (condition){
  // your code goes here
} // Close the code block

Project vs Repository in GitHub

GitHub recently introduced a new feature called Projects. This provides a visual board that is typical of many Project Management tools:

Project

A Repository as documented on GitHub:

A repository is the most basic element of GitHub. They're easiest to imagine as a project's folder. A repository contains all of the project files (including documentation), and stores each file's revision history. Repositories can have multiple collaborators and can be either public or private.

A Project as documented on GitHub:

Project boards on GitHub help you organize and prioritize your work. You can create project boards for specific feature work, comprehensive roadmaps, or even release checklists. With project boards, you have the flexibility to create customized workflows that suit your needs.

Part of the confusion is that the new feature, Projects, conflicts with the overloaded usage of the term project in the documentation above.

How to set some xlim and ylim in Seaborn lmplot facetgrid

The lmplot function returns a FacetGrid instance. This object has a method called set, to which you can pass key=value pairs and they will be set on each Axes object in the grid.

Secondly, you can set only one side of an Axes limit in matplotlib by passing None for the value you want to remain as the default.

Putting these together, we have:

g = sns.lmplot('X', 'Y', df, col='Z', sharex=False, sharey=False)
g.set(ylim=(0, None))

enter image description here

Border Height on CSS

Just like everyone else said, you can't control border height. But there are workarounds, here's what I do:

table {
  position: relative;
}

table::before { /* ::after works too */
  content: "";
  position: absolute;
  right: 0; /* Change direction for a different side*/
  z-index: 100; 
  width: 3px; /* Thickness */
  height: 10px;
  background: #555; /* Color */
}

You can set height to inherit for the height of the table or calc(inherit - 2px) for a 2px smaller border. Remember, inherit has no effect when the table height isn't set.

Use height: 50% for half a border.

Demo

Getting the array length of a 2D array in Java

import java.util.Arrays;

public class Main {

    public static void main(String[] args) 
    {

        double[][] test = { {100}, {200}, {300}, {400}, {500}, {600}, {700}, {800}, {900}, {1000}};

        int [][] removeRow = { {0}, {1}, {3}, {4}, };

        double[][] newTest = new double[test.length - removeRow.length][test[0].length];

        for (int i = 0, j = 0, k = 0; i < test.length; i++) {
            if (j < removeRow.length) {
                if (i == removeRow[j][0]) {
                    j++;
                    continue;
                }
            }
            newTest[k][0] = test[i][0];
            k++;
        }

        System.out.println(Arrays.deepToString(newTest));   
    }
}

Tomcat: LifecycleException when deploying

I got this error when there was no enough space in server. check logs and server spaces

MS-DOS Batch file pause with enter key

You can do it with the pause command, example:

dir
pause
echo Now about to end...
pause

Laravel Advanced Wheres how to pass variable into function?

If you are using Laravel eloquent you may try this as well.

$result = self::select('*')
                    ->with('user')
                    ->where('subscriptionPlan', function($query) use($activated){
                        $query->where('activated', '=', $roleId);
                    })
                    ->get();

Add padding to HTML text input field

You can provide padding to an input like this:

HTML:

<input type=text id=firstname />

CSS:

input {
    width: 250px;
    padding: 5px;
}

however I would also add:

input {
    width: 250px;
    padding: 5px;
    -webkit-box-sizing: border-box; /* Safari/Chrome, other WebKit */
    -moz-box-sizing: border-box;    /* Firefox, other Gecko */
    box-sizing: border-box;         /* Opera/IE 8+ */
}

Box sizing makes the input width stay at 250px rather than increase to 260px due to the padding.

For reference.

How to unescape HTML character entities in Java?

Consider using the HtmlManipulator Java class. You may need to add some items (not all entities are in the list).

The Apache Commons StringEscapeUtils as suggested by Kevin Hakanson did not work 100% for me; several entities like &#145 (left single quote) were translated into '222' somehow. I also tried org.jsoup, and had the same problem.

Can I nest a <button> element inside an <a> using HTML5?

If you're using Bootstrap 3, this works quite well

<a href="#" class="btn btn-primary btn-lg active" role="button">Primary link</a>
<a href="#" class="btn btn-default btn-lg active" role="button">Link</a>

How to get row from R data.frame

If you don't know the row number, but do know some values then you can use subset

x <- structure(list(A = c(5,    3.5, 3.25, 4.25,  1.5 ), 
                    B = c(4.25, 4,   4,    4.5,   4.5 ),
                    C = c(4.5,  2.5, 4,    2.25,  3   )
               ),
               .Names    = c("A", "B", "C"),
               class     = "data.frame",
               row.names = c(NA, -5L)
     )

subset(x, A ==5 & B==4.25 & C==4.5)

Inconsistent accessibility: property type is less accessible

Your Delivery class is internal (the default visibility for classes), however the property (and presumably the containing class) are public, so the property is more accessible than the Delivery class. You need to either make Delivery public, or restrict the visibility of the thelivery property.

How do I display the current value of an Android Preference in the Preference summary?

If you only want to display the plain text value of each field as its summary, the following code should be the easiest to maintain. It requires only two changes (lines 13 and 21, marked with "change here"):

package com.my.package;

import android.content.SharedPreferences;
import android.content.SharedPreferences.OnSharedPreferenceChangeListener;
import android.os.Bundle;
import android.preference.EditTextPreference;
import android.preference.ListPreference;
import android.preference.Preference;
import android.preference.PreferenceActivity;

public class PreferencesActivity extends PreferenceActivity implements OnSharedPreferenceChangeListener {

    private final String[] mAutoSummaryFields = { "pref_key1", "pref_key2", "pref_key3" }; // change here
    private final int mEntryCount = mAutoSummaryFields.length;
    private Preference[] mPreferenceEntries;

    @SuppressWarnings("deprecation")
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.preferences_file); // change here
        mPreferenceEntries = new Preference[mEntryCount];
        for (int i = 0; i < mEntryCount; i++) {
            mPreferenceEntries[i] = getPreferenceScreen().findPreference(mAutoSummaryFields[i]);
        }
    }

    @SuppressWarnings("deprecation")
    @Override
    protected void onResume() {
        super.onResume();
        for (int i = 0; i < mEntryCount; i++) {
            updateSummary(mAutoSummaryFields[i]); // initialization
        }
        getPreferenceScreen().getSharedPreferences().registerOnSharedPreferenceChangeListener(this); // register change listener
    }

    @SuppressWarnings("deprecation")
    @Override
    protected void onPause() {
        super.onPause();
        getPreferenceScreen().getSharedPreferences().unregisterOnSharedPreferenceChangeListener(this); // unregister change listener
    }

    private void updateSummary(String key) {
        for (int i = 0; i < mEntryCount; i++) {
            if (key.equals(mAutoSummaryFields[i])) {
                if (mPreferenceEntries[i] instanceof EditTextPreference) {
                    final EditTextPreference currentPreference = (EditTextPreference) mPreferenceEntries[i];
                    mPreferenceEntries[i].setSummary(currentPreference.getText());
                }
                else if (mPreferenceEntries[i] instanceof ListPreference) {
                    final ListPreference currentPreference = (ListPreference) mPreferenceEntries[i];
                    mPreferenceEntries[i].setSummary(currentPreference.getEntry());
                }
                break;
            }
        }
    }

    public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
        updateSummary(key);
    }

}

node.js, socket.io with SSL

Depending on your needs, you could allow both secure and unsecure connections and still only use one Socket.io instance.

You simply have to instanciate two servers, one for HTTP and one for HTTPS, then attach those servers to the Socket.io instance.

Server side :

// needed to read certificates from disk
const fs          = require( "fs"    );

// Servers with and without SSL
const http        = require( "http"  )
const https       = require( "https" );
const httpPort    = 3333;
const httpsPort   = 3334;
const httpServer  = http.createServer();
const httpsServer = https.createServer({
    "key" : fs.readFileSync( "yourcert.key" ),
    "cert": fs.readFileSync( "yourcert.crt" ),
    "ca"  : fs.readFileSync( "yourca.crt"   )
});
httpServer.listen( httpPort, function() {
    console.log(  `Listening HTTP on ${httpPort}` );
});
httpsServer.listen( httpsPort, function() {
    console.log(  `Listening HTTPS on ${httpsPort}` );
});

// Socket.io
const ioServer = require( "socket.io" );
const io       = new ioServer();
io.attach( httpServer  );
io.attach( httpsServer );

io.on( "connection", function( socket ) {

    console.log( "user connected" );
    // ... your code

});

Client side :

var url    = "//example.com:" + ( window.location.protocol == "https:" ? "3334" : "3333" );
var socket = io( url, {
    // set to false only if you use self-signed certificate !
    "rejectUnauthorized": true
});
socket.on( "connect", function( e ) {
    console.log( "connect", e );
});

If your NodeJS server is different from your Web server, you will maybe need to set some CORS headers. So in the server side, replace:

const httpServer  = http.createServer();
const httpsServer = https.createServer({
    "key" : fs.readFileSync( "yourcert.key" ),
    "cert": fs.readFileSync( "yourcert.crt" ),
    "ca"  : fs.readFileSync( "yourca.crt"   )
});

With:

const CORS_fn = (req, res) => {
    res.setHeader( "Access-Control-Allow-Origin"     , "*"    );
    res.setHeader( "Access-Control-Allow-Credentials", "true" );
    res.setHeader( "Access-Control-Allow-Methods"    , "*"    );
    res.setHeader( "Access-Control-Allow-Headers"    , "*"    );
    if ( req.method === "OPTIONS" ) {
        res.writeHead(200);
        res.end();
        return;
    }
};
const httpServer  = http.createServer( CORS_fn );
const httpsServer = https.createServer({
        "key" : fs.readFileSync( "yourcert.key" ),
        "cert": fs.readFileSync( "yourcert.crt" ),
        "ca"  : fs.readFileSync( "yourca.crt"   )
}, CORS_fn );

And of course add/remove headers and set the values of the headers according to your needs.

maven "cannot find symbol" message unhelpful

I was getting a similar problem in Eclipse STS when trying to run a Maven install on a project. I had changed some versions in the dependencies of my pom.xml file for that project and the projects that those dependencies pointed to. I solved it by running a Maven install on all the projects I changed and then running install on the original one again.

How to get hostname from IP (Linux)?

Another simple way I found for using in LAN is

ssh [username@ip] uname -n

If you need to login command line will be

sshpass -p "[password]" ssh [username@ip] uname -n

document.createElement("script") synchronously

This isn't pretty, but it works:

<script type="text/javascript">
  document.write('<script type="text/javascript" src="other.js"></script>');
</script>

<script type="text/javascript">
  functionFromOther();
</script>

Or

<script type="text/javascript">
  document.write('<script type="text/javascript" src="other.js"></script>');
  window.onload = function() {
    functionFromOther();
  };
</script>

The script must be included either in a separate <script> tag or before window.onload().

This will not work:

<script type="text/javascript">
  document.write('<script type="text/javascript" src="other.js"></script>');
  functionFromOther(); // Error
</script>

The same can be done with creating a node, as Pointy did, but only in FF. You have no guarantee when the script will be ready in other browsers.

Being an XML Purist I really hate this. But it does work predictably. You could easily wrap those ugly document.write()s so you don't have to look at them. You could even do tests and create a node and append it then fall back on document.write().

How do you add input from user into list in Python

shopList = [] 
maxLengthList = 6
while len(shopList) < maxLengthList:
    item = input("Enter your Item to the List: ")
    shopList.append(item)
    print shopList
print "That's your Shopping List"
print shopList

Where are SQL Server connection attempts logged?

Another way to check on connection attempts is to look at the server's event log. On my Windows 2008 R2 Enterprise machine I opened the server manager (right-click on Computer and select Manage. Then choose Diagnostics -> Event Viewer -> Windows Logs -> Applcation. You can filter the log to isolate the MSSQLSERVER events. I found a number that looked like this

Login failed for user 'bogus'. The user is not associated with a trusted SQL Server connection. [CLIENT: 10.12.3.126]

What is the T-SQL To grant read and write access to tables in a database in SQL Server?

In SQL Server 2012, 2014:

USE mydb
GO

ALTER ROLE db_datareader ADD MEMBER MYUSER
GO
ALTER ROLE db_datawriter ADD MEMBER MYUSER
GO

In SQL Server 2008:

use mydb
go

exec sp_addrolemember db_datareader, MYUSER 
go
exec sp_addrolemember db_datawriter, MYUSER 
go

To also assign the ability to execute all Stored Procedures for a Database:

GRANT EXECUTE TO MYUSER;

To assign the ability to execute specific stored procedures:

GRANT EXECUTE ON dbo.sp_mystoredprocedure TO MYUSER;

setup.py examples?

Look at this complete example https://github.com/marcindulak/python-mycli of a small python package. It is based on packaging recommendations from https://packaging.python.org/en/latest/distributing.html, uses setup.py with distutils and in addition shows how to create RPM and deb packages.

The project's setup.py is included below (see the repo for the full source):

#!/usr/bin/env python

import os
import sys

from distutils.core import setup

name = "mycli"

rootdir = os.path.abspath(os.path.dirname(__file__))

# Restructured text project description read from file
long_description = open(os.path.join(rootdir, 'README.md')).read()

# Python 2.4 or later needed
if sys.version_info < (2, 4, 0, 'final', 0):
    raise SystemExit, 'Python 2.4 or later is required!'

# Build a list of all project modules
packages = []
for dirname, dirnames, filenames in os.walk(name):
        if '__init__.py' in filenames:
            packages.append(dirname.replace('/', '.'))

package_dir = {name: name}

# Data files used e.g. in tests
package_data = {name: [os.path.join(name, 'tests', 'prt.txt')]}

# The current version number - MSI accepts only version X.X.X
exec(open(os.path.join(name, 'version.py')).read())

# Scripts
scripts = []
for dirname, dirnames, filenames in os.walk('scripts'):
    for filename in filenames:
        if not filename.endswith('.bat'):
            scripts.append(os.path.join(dirname, filename))

# Provide bat executables in the tarball (always for Win)
if 'sdist' in sys.argv or os.name in ['ce', 'nt']:
    for s in scripts[:]:
        scripts.append(s + '.bat')

# Data_files (e.g. doc) needs (directory, files-in-this-directory) tuples
data_files = []
for dirname, dirnames, filenames in os.walk('doc'):
        fileslist = []
        for filename in filenames:
            fullname = os.path.join(dirname, filename)
            fileslist.append(fullname)
        data_files.append(('share/' + name + '/' + dirname, fileslist))

setup(name='python-' + name,
      version=version,  # PEP440
      description='mycli - shows some argparse features',
      long_description=long_description,
      url='https://github.com/marcindulak/python-mycli',
      author='Marcin Dulak',
      author_email='[email protected]',
      license='ASL',
      # https://pypi.python.org/pypi?%3Aaction=list_classifiers
      classifiers=[
          'Development Status :: 1 - Planning',
          'Environment :: Console',
          'License :: OSI Approved :: Apache Software License',
          'Natural Language :: English',
          'Operating System :: OS Independent',
          'Programming Language :: Python :: 2',
          'Programming Language :: Python :: 2.4',
          'Programming Language :: Python :: 2.5',
          'Programming Language :: Python :: 2.6',
          'Programming Language :: Python :: 2.7',
          'Programming Language :: Python :: 3',
          'Programming Language :: Python :: 3.2',
          'Programming Language :: Python :: 3.3',
          'Programming Language :: Python :: 3.4',
      ],
      keywords='argparse distutils cli unittest RPM spec deb',
      packages=packages,
      package_dir=package_dir,
      package_data=package_data,
      scripts=scripts,
      data_files=data_files,
      )

and and RPM spec file which more or less follows Fedora/EPEL packaging guidelines may look like:

# Failsafe backport of Python2-macros for RHEL <= 6
%{!?python_sitelib: %global python_sitelib      %(%{__python} -c "from distutils.sysconfig import get_python_lib; print(get_python_lib())")}
%{!?python_sitearch:    %global python_sitearch     %(%{__python} -c "from distutils.sysconfig import get_python_lib; print(get_python_lib(1))")}
%{!?python_version: %global python_version      %(%{__python} -c "import sys; sys.stdout.write(sys.version[:3])")}
%{!?__python2:      %global __python2       %{__python}}
%{!?python2_sitelib:    %global python2_sitelib     %{python_sitelib}}
%{!?python2_sitearch:   %global python2_sitearch    %{python_sitearch}}
%{!?python2_version:    %global python2_version     %{python_version}}

%{!?python2_minor_version: %define python2_minor_version %(%{__python} -c "import sys ; print sys.version[2:3]")}

%global upstream_name mycli


Name:           python-%{upstream_name}
Version:        0.0.1
Release:        1%{?dist}
Summary:        A Python program that demonstrates usage of argparse
%{?el5:Group:       Applications/Scientific}
License:        ASL 2.0

URL:            https://github.com/marcindulak/%{name}
Source0:        https://github.com/marcindulak/%{name}/%{name}-%{version}.tar.gz

%{?el5:BuildRoot:   %(mktemp -ud %{_tmppath}/%{name}-%{version}-%{release}-XXXXXX)}
BuildArch:      noarch

%if 0%{?suse_version}
BuildRequires:      python-devel
%else
BuildRequires:      python2-devel
%endif


%description
A Python program that demonstrates usage of argparse.


%prep
%setup -qn %{name}-%{version}


%build
%{__python2} setup.py build


%install
%{?el5:rm -rf $RPM_BUILD_ROOT}
%{__python2} setup.py install --skip-build --prefix=%{_prefix} \
   --optimize=1 --root $RPM_BUILD_ROOT


%check
export PYTHONPATH=`pwd`/build/lib
export PATH=`pwd`/build/scripts-%{python2_version}:${PATH}
%if 0%{python2_minor_version} >= 7
%{__python2} -m unittest discover -s %{upstream_name}/tests -p '*.py'
%endif


%clean
%{?el5:rm -rf $RPM_BUILD_ROOT}


%files
%doc LICENSE README.md
%{_bindir}/*
%{python2_sitelib}/%{upstream_name}
%{?!el5:%{python2_sitelib}/*.egg-info}


%changelog
* Wed Jan 14 2015 Marcin Dulak <[email protected]> - 0.0.1-1
- initial version

get selected value in datePicker and format it

$('#scheduleDate').datepicker({ dateFormat : 'dd, MM, yy'});

var dateFormat = $('#scheduleDate').datepicker('option', 'dd, MM, yy');

$('#scheduleDate').datepicker('option', 'dateFormat', 'dd, MM, yy');

var result = $('#scheduleDate').val();

alert('result: ' + result);

result: 20, April, 2012

Place API key in Headers or URL

passing api key in parameters makes it difficult for clients to keep their APIkeys secret, they tend to leak keys on a regular basis. A better approach is to pass it in header of request url.you can set user-key header in your code . For testing your request Url you can use Postman app in google chrome by setting user-key header to your api-key.

fatal error LNK1112: module machine type 'x64' conflicts with target machine type 'X86'

This happened to me today because I had added a library directory while still in x86 mode, and accidently removed the inherited directories, making them hardcoded instead. Then after switching to x64, my VC++ Directories still read:

"...;$(VC_LibraryPath_x86);$(WindowsSDK_LibraryPath_x86);"

instead of the _x64.

lvalue required as left operand of assignment

You need to compare, not assign:

if (strcmp("hello", "hello") == 0)
                             ^

Because you want to check if the result of strcmp("hello", "hello") equals to 0.

About the error:

lvalue required as left operand of assignment

lvalue means an assignable value (variable), and in assignment the left value to the = has to be lvalue (pretty clear).

Both function results and constants are not assignable (rvalues), so they are rvalues. so the order doesn't matter and if you forget to use == you will get this error. (edit:)I consider it a good practice in comparison to put the constant in the left side, so if you write = instead of ==, you will get a compilation error. for example:

int a = 5;
if (a = 0) // Always evaluated as false, no error.
{
    //...
}

vs.

int a = 5;
if (0 = a) // Generates compilation error, you cannot assign a to 0 (rvalue)
{
    //...
}

(see first answer to this question: https://stackoverflow.com/questions/2349378/new-programming-jargon-you-coined)

java.net.SocketException: Connection reset by peer: socket write error When serving a file

It is possible for the TCP socket to be "closing" and your code to not have yet been notified.

Here is a animation for the life cycle. http://tcp.cs.st-andrews.ac.uk/index.shtml?page=connection_lifecycle

Basically, the connection was closed by the client. You already have throws IOException and SocketException extends IOException. This is working just fine. You just need to properly handle IOException because it is a normal part of the api.

EDIT: The RST packet occurs when a packet is received on a socket which does not exist or was closed. There is no difference to your application. Depending on the implementation the reset state may stick and closed will never officially occur.

Check if Nullable Guid is empty in c#

Beginning with C# 7.1, you can use default literal to produce the default value of a type when the compiler can infer the expression type.

Console.Writeline(default(Guid));  
   // ouptut: 00000000-0000-0000-0000-000000000000

Console.WriteLine(default(int));  // output: 0

Console.WriteLine(default(object) is null);  // output: True

https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/default

Find an element in DOM based on an attribute value

Update: In the past few years the landscape has changed drastically. You can now reliably use querySelector and querySelectorAll, see Wojtek's answer for how to do this.

There's no need for a jQuery dependency now. If you're using jQuery, great...if you're not, you need not rely it on just for selecting elements by attributes anymore.


There's not a very short way to do this in vanilla javascript, but there are some solutions available.

You do something like this, looping through elements and checking the attribute

If a library like jQuery is an option, you can do it a bit easier, like this:

$("[myAttribute=value]")

If the value isn't a valid CSS identifier (it has spaces or punctuation in it, etc.), you need quotes around the value (they can be single or double):

$("[myAttribute='my value']")

You can also do start-with, ends-with, contains, etc...there are several options for the attribute selector.

How can I sharpen an image in OpenCV?

Try with this:

cv::bilateralFilter(img, 9, 75, 75);

You might find more information here.

How do I get the App version and build number using Swift?

For Swift 5.0 :

let appVersion = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as! String

jQuery Mobile - back button

Newer versions of JQuery mobile API (I guess its newer than 1.5) require adding 'back' button explicitly in header or bottom of each page.

So, try adding this in your page div tags:

data-add-back-btn="true"
data-back-btn-text="Back"

Example:

<div data-role="page" id="page2" data-add-back-btn="true" data-back-btn-text="Back">

How to strip all whitespace from string

Taking advantage of str.split's behavior with no sep parameter:

>>> s = " \t foo \n bar "
>>> "".join(s.split())
'foobar'

If you just want to remove spaces instead of all whitespace:

>>> s.replace(" ", "")
'\tfoo\nbar'

Premature optimization

Even though efficiency isn't the primary goal—writing clear code is—here are some initial timings:

$ python -m timeit '"".join(" \t foo \n bar ".split())'
1000000 loops, best of 3: 1.38 usec per loop
$ python -m timeit -s 'import re' 're.sub(r"\s+", "", " \t foo \n bar ")'
100000 loops, best of 3: 15.6 usec per loop

Note the regex is cached, so it's not as slow as you'd imagine. Compiling it beforehand helps some, but would only matter in practice if you call this many times:

$ python -m timeit -s 'import re; e = re.compile(r"\s+")' 'e.sub("", " \t foo \n bar ")'
100000 loops, best of 3: 7.76 usec per loop

Even though re.sub is 11.3x slower, remember your bottlenecks are assuredly elsewhere. Most programs would not notice the difference between any of these 3 choices.

How to pass parameters to a Script tag?

it is a very old thread, I know but this might help too if somebody gets here once they search for a solution.

Basically I used the document.currentScript to get the element from where my code is running and I filter using the name of the variable I am looking for. I did it extending currentScript with a method called "get", so we will be able to fetch the value inside that script by using:

document.currentScript.get('get_variable_name');

In this way we can use standard URI to retrieve the variables without adding special attributes.

This is the final code

document.currentScript.get = function(variable) {
    if(variable=(new RegExp('[?&]'+encodeURIComponent(variable)+'=([^&]*)')).exec(this.src))
    return decodeURIComponent(variable[1]);
};

I was forgetting about IE :) It could not be that easier... Well I did not mention that document.currentScript is a HTML5 property. It has not been included for different versions of IE (I tested until IE11, and it was not there yet). For IE compatibility, I added this portion to the code:

document.currentScript = document.currentScript || (function() {
  var scripts = document.getElementsByTagName('script');
  return scripts[scripts.length - 1];
})();

What we are doing here is to define some alternative code for IE, which returns the current script object, which is required in the solution to extract parameters from the src property. This is not the perfect solution for IE since there are some limitations; If the script is loaded asynchronously. Newer browsers should include ".currentScript" property.

I hope it helps.

Why does Git treat this text file as a binary file?

This is also caused (on Windows at least) by text files that have UTF-8 with BOM encoding. Changing the encoding to regular UTF-8 immediately made Git see the file as type=text

JAX-RS — How to return JSON and HTTP status code together?

Please look at the example here, it best illustrates the problem and how it is solved in the latest (2.3.1) version of Jersey.

https://jersey.java.net/documentation/latest/representations.html#d0e3586

It basically involves defining a custom Exception and keeping the return type as the entity. When there is an error, the exception is thrown, otherwise, you return the POJO.

How do I use the nohup command without getting nohup.out?

If you have a BASH shell on your mac/linux in-front of you, you try out the below steps to understand the redirection practically :

Create a 2 line script called zz.sh

#!/bin/bash
echo "Hello. This is a proper command"
junk_errorcommand
  • The echo command's output goes into STDOUT filestream (file descriptor 1).
  • The error command's output goes into STDERR filestream (file descriptor 2)

Currently, simply executing the script sends both STDOUT and STDERR to the screen.

./zz.sh

Now start with the standard redirection :

zz.sh > zfile.txt

In the above, "echo" (STDOUT) goes into the zfile.txt. Whereas "error" (STDERR) is displayed on the screen.

The above is the same as :

zz.sh 1> zfile.txt

Now you can try the opposite, and redirect "error" STDERR into the file. The STDOUT from "echo" command goes to the screen.

zz.sh 2> zfile.txt

Combining the above two, you get:

zz.sh 1> zfile.txt 2>&1

Explanation:

  • FIRST, send STDOUT 1 to zfile.txt
  • THEN, send STDERR 2 to STDOUT 1 itself (by using &1 pointer).
  • Therefore, both 1 and 2 goes into the same file (zfile.txt)

Eventually, you can pack the whole thing inside nohup command & to run it in the background:

nohup zz.sh 1> zfile.txt 2>&1&

Formatting a field using ToText in a Crystal Reports formula field

I think you are looking for ToText(CCur(@Price}/{ValuationReport.YestPrice}*100-100))

You can use CCur to convert numbers or string to Curency formats. CCur(number) or CCur(string)


I think this may be what you are looking for,

Replace (ToText(CCur({field})),"$" , "") that will give the parentheses for negative numbers

It is a little hacky, but I'm not sure CR is very kind in the ways of formatting

Accessing elements of Python dictionary by index

If the questions is, if I know that I have a dict of dicts that contains 'Apple' as a fruit and 'American' as a type of apple, I would use:

myDict = {'Apple': {'American':'16', 'Mexican':10, 'Chinese':5},
          'Grapes':{'Arabian':'25','Indian':'20'} }


print myDict['Apple']['American']

as others suggested. If instead the questions is, you don't know whether 'Apple' as a fruit and 'American' as a type of 'Apple' exist when you read an arbitrary file into your dict of dict data structure, you could do something like:

print [ftype['American'] for f,ftype in myDict.iteritems() if f == 'Apple' and 'American' in ftype]

or better yet so you don't unnecessarily iterate over the entire dict of dicts if you know that only Apple has the type American:

if 'Apple' in myDict:
    if 'American' in myDict['Apple']:
        print myDict['Apple']['American']

In all of these cases it doesn't matter what order the dictionaries actually store the entries. If you are really concerned about the order, then you might consider using an OrderedDict:

http://docs.python.org/dev/library/collections.html#collections.OrderedDict

Gradient borders

border-image-slice will extend a CSS border-image gradient

This (as I understand it) prevents the default slicing of the "image" into sections - without it, nothing appears if the border is on one side only, and if it's around the entire element four tiny gradients appear in each corner.

  border-bottom: 6px solid transparent;
  border-image: linear-gradient(to right, red , yellow);
  border-image-slice: 1;

How do I get the last character of a string using an Excel function?

Looks like the answer above was a little incomplete try the following:-

=RIGHT(A2,(LEN(A2)-(LEN(A2)-1)))

Obviously, this is for cell A2...

What this does is uses a combination of Right and Len - Len is the length of a string and in this case, we want to remove all but one from that... clearly, if you wanted the last two characters you'd change the -1 to -2 etc etc etc.

After the length has been determined and the portion of that which is required - then the Right command will display the information you need.

This works well combined with an IF statement - I use this to find out if the last character of a string of text is a specific character and remove it if it is. See, the example below for stripping out commas from the end of a text string...

=IF(RIGHT(A2,(LEN(A2)-(LEN(A2)-1)))=",",LEFT(A2,(LEN(A2)-1)),A2)

How to play a sound using Swift?

import AVFoundation
var player:AVAudioPlayer!

func Play(){
    guard let path = Bundle.main.path(forResource: "KurdishSong", ofType: "mp3")else{return}
    let soundURl = URL(fileURLWithPath: path)
    player = try? AVAudioPlayer(contentsOf: soundURl)
    player.prepareToPlay()
    player.play()
    //player.pause()
    //player.stop()
}

Android WebView progress bar

For a horizontal progress bar, you first need to define your progress bar and link it with your XML file like this, in the onCreate:

final TextView txtview = (TextView)findViewById(R.id.tV1);
final ProgressBar pbar = (ProgressBar) findViewById(R.id.pB1);

Then, you may use onProgressChanged Method in your WebChromeClient:

MyView.setWebChromeClient(new WebChromeClient() {
            public void onProgressChanged(WebView view, int progress) {
               if(progress < 100 && pbar.getVisibility() == ProgressBar.GONE){
                   pbar.setVisibility(ProgressBar.VISIBLE);
                   txtview.setVisibility(View.VISIBLE);
               }

               pbar.setProgress(progress);
               if(progress == 100) {
                   pbar.setVisibility(ProgressBar.GONE);
                   txtview.setVisibility(View.GONE);
               }
            }
        });

After that, in your layout you have something like this

<TextView android:text="Loading, . . ." 
    android:textAppearance="?android:attr/textAppearanceSmall"
    android:id="@+id/tV1" android:layout_height="wrap_content"
    android:layout_width="wrap_content"
    android:textColor="#000000"></TextView>

<ProgressBar android:id="@+id/pB1"
    style="?android:attr/progressBarStyleHorizontal" android:layout_width="fill_parent"
    android:layout_height="wrap_content" android:layout_centerVertical="true"
    android:padding="2dip">
</ProgressBar>

This is how I did it in my app.

How to get href value using jQuery?

You need

var href = $(this).attr('href');

Inside a jQuery click handler, the this object refers to the element clicked, whereas in your case you're always getting the href for the first <a> on the page. This, incidentally, is why your example works but your real code doesn't

How to format a phone number with jQuery

An alternative solution:

_x000D_
_x000D_
function numberWithSpaces(value, pattern) {_x000D_
  var i = 0,_x000D_
    phone = value.toString();_x000D_
  return pattern.replace(/#/g, _ => phone[i++]);_x000D_
}_x000D_
_x000D_
console.log(numberWithSpaces('2124771000', '###-###-####'));
_x000D_
_x000D_
_x000D_

How to add an extra language input to Android?

Don't agree with post above. I have a Hero with only English available and I want Spanish.

I installed MoreLocale 2, and it has lots of different languages (Dutch among them). I choose Spanish, Sense UI restarted and EVERYTHING in my phone changed to Spanish: menus, settings, etc. The keyboard predictive text defaulted to Spanish and started suggesting words in Spanish. This means, somewhere within the OS there is a Spanish dictionary hidden and MoreLocale made it available.

The problem is that English is still the only option available in keyboard input language so I can switch to English but can't switch back to Spanish unless I restart Sense UI, which takes a couple of minutes so not a very practical solution.

Still looking for an easier way to do it so please help.

Which is best data type for phone number in MySQL and what should Java type mapping for it be?

you can use var-char,String,and int ,it depends on you, if you use only country code with mobile number than you can use int,if you use special formate for number than use String or var-char type, if you use var-char then must defile size of number and restrict from user.

How can I list all cookies for the current page with Javascript?

No.

The only API browsers give you for handling cookies is getting and setting them via key-value pairs. All browsers handle cookies by domain name only.

Accessing all cookies for current domain is done via document.cookie.

How to List All Redis Databases?

There is no command to do it (like you would do it with MySQL for instance). The number of Redis databases is fixed, and set in the configuration file. By default, you have 16 databases. Each database is identified by a number (not a name).

You can use the following command to know the number of databases:

CONFIG GET databases
1) "databases"
2) "16"

You can use the following command to list the databases for which some keys are defined:

INFO keyspace
# Keyspace
db0:keys=10,expires=0
db1:keys=1,expires=0
db3:keys=1,expires=0

Please note that you are supposed to use the "redis-cli" client to run these commands, not telnet. If you want to use telnet, then you need to run these commands formatted using the Redis protocol.

For instance:

*2
$4
INFO
$8
keyspace

$79
# Keyspace
db0:keys=10,expires=0
db1:keys=1,expires=0
db3:keys=1,expires=0

You can find the description of the Redis protocol here: http://redis.io/topics/protocol

I'm getting the "missing a using directive or assembly reference" and no clue what's going wrong

I had the same problem earlier today. I could not figure out why the class file I was trying to reference was not being seen by the compiler. I had recently changed the namespace of the class file in question to a different but already existing namespace. (I also had using references to the class's new and previous namespaces where I was trying to instantiate it)

Where the compiler was telling me I was missing a reference when trying to instantiate the class, I right clicked and hit "generate class stub". Once Visual Studio generated a class stub for me, I coped and pasted the code from the old class file into this stub, saved the stub and when I tried to compile again it worked! No issues.

Might be a solution specific to my build, but its worth a try.

What is the difference between Scala's case class and class?

  • Case classes can be pattern matched
  • Case classes automatically define hashcode and equals
  • Case classes automatically define getter methods for the constructor arguments.

(You already mentioned all but the last one).

Those are the only differences to regular classes.

Is there a way to check for both `null` and `undefined`?

I think this answer needs an update, check the edit history for the old answer.

Basically, you have three deferent cases null, undefined, and undeclared, see the snippet below.

// bad-file.ts
console.log(message)

You'll get an error says that variable message is undefined (aka undeclared), of course, the Typescript compiler shouldn't let you do that but REALLY nothing can prevent you.

// evil-file.ts
// @ts-gnore
console.log(message)

The compiler will be happy to just compile the code above. So, if you're sure that all variables are declared you can simply do that

if ( message != null ) {
    // do something with the message
}

the code above will check for null and undefined, BUT in case the message variable may be undeclared (for safety), you may consider the following code

if ( typeof(message) !== 'undefined' && message !== null ) {
    // message variable is more than safe to be used.
}

Note: the order here typeof(message) !== 'undefined' && message !== null is very important you have to check for the undefined state first atherwise it will be just the same as message != null, thanks @Jaider.

NoClassDefFoundError - Eclipse and Android

I had this problem and it was caused by not "exporting" the library.Issue was just because the .class files for some classes are not available while packaging the APK.Compile time it will work fine with out exporiting

In my case I was using "CusrsorAdapter" class and under "JavaBuildPath->Order and Export" I didn't check the support V4 jar.Once it is selected issue is gone.

To make sure you are getting noClassDefFound error because of above reason, please check your logacat, you will see unknown super classs error at run time.

How to call a C# function from JavaScript?

If you're meaning to make a server call from the client, you should use Ajax - look at something like Jquery and use $.Ajax() or $.getJson() to call the server function, depending on what kind of return you're after or action you want to execute.

trim left characters in sql server?

To remove the left-most word, you'll need to use either RIGHT or SUBSTRING. Assuming you know how many characters are involved, that would look either of the following:

SELECT RIGHT('Hello World', 5)
SELECT SUBSTRING('Hello World', 6, 100)

If you don't know how many characters that first word has, you'll need to find out using CHARINDEX, then substitute that value back into SUBSTRING:

SELECT SUBSTRING('Hello World', CHARINDEX(' ', 'Hello World') + 1, 100)

This finds the position of the first space, then takes the remaining characters to the right.

git revert back to certain commit

http://www.kernel.org/pub/software/scm/git/docs/git-revert.html

using git revert <commit> will create a new commit that reverts the one you dont want to have.

You can specify a list of commits to revert.

An alternative: http://git-scm.com/docs/git-reset

git reset will reset your copy to the commit you want.

What is the coolest thing you can do in <10 lines of simple code? Help me inspire beginners!

I think it's tough to be a computer educator these days. I am. We face an increasingly steep uphill battle. Our students are incredibly sophisticated users and it takes a lot to impress them. They have so many tools accessible to them that do amazing things.

A simple calculator in 10 lines of code? Why? I've got a TI-86 for that.

A script that applies special effects to an image? That's what Photoshop is for. And Photoshop blows away anything you can do in 10 lines.

How about ripping a CD and converting the file to MP3? Uhh, I already have 50,000 songs I got from BitTorrent. They're already in MP3 format. I play them on my iPhone. Who buys CDs anyway?

To introduce savvy users to programming, you're going to have to find something that's:

a) applicable to something they find interesting and cool, and b) does something they can't already do.

Assume your students already have access to the most expensive software. Many of them do have the full version of Adobe CS5.5 (retail price: $2,600; actual price: free) and can easily get any application that would normally break your department's budget.

But the vast majority of them have no idea how any of this "computer stuff" actually works.

They are an incredibly creative bunch: they like to create things. They just want to be able to do or make something that their friends can't. They want something to brag about.

Here are some things that I've found to resonate with my students:

  • HTML and CSS. From those they learn how MySpace themes work and can customize them.
  • Mashups. They've all seen them, but don't know how to create them. Check out Yahoo! Pipes. There are lots of teachable moments, such as RSS, XML, text filtering, mapping, and visualization. The completed mashup widgets can be embedded in web pages.
  • Artwork. Look at Context-Free Art. Recursion and randomization are key to making beautiful pictures.
  • Storytelling. With an easy-to-use 3D programming environment like Alice, it's easy to create high-quality, engaging stories using nothing more than drag-and-drop.

None of these involve any programming in the traditional sense. But they do leverage powerful libraries. I think of them as a different kind of programming.

JUnit Eclipse Plugin?

It's built in Eclipse since ages. Which Eclipse version are you using? How were you trying to create a new JUnit test case? It should be File > New > Other > Java - JUnit - JUnit Test Case (you can eventually enter Filter text "junit").

On localhost, how do I pick a free port number?

For the sake of snippet of what the guys have explained above:

import socket
from contextlib import closing

def find_free_port():
    with closing(socket.socket(socket.AF_INET, socket.SOCK_STREAM)) as s:
        s.bind(('', 0))
        s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        return s.getsockname()[1]

How do I uninstall a package installed using npm link?

"npm install" replaces all dependencies in your node_modules installed with "npm link" with versions from npmjs (specified in your package.json)

Error in Python IOError: [Errno 2] No such file or directory: 'data.csv'

It's looking for the file in the current directory.

First, go to that directory

cd /users/gcameron/Desktop/map

And then try to run it

python colorize_svg.py

Create a pointer to two-dimensional array

Here you wanna make a pointer to the first element of the array

uint8_t (*matrix_ptr)[20] = l_matrix;

With typedef, this looks cleaner

typedef uint8_t array_of_20_uint8_t[20];
array_of_20_uint8_t *matrix_ptr = l_matrix;

Then you can enjoy life again :)

matrix_ptr[0][1] = ...;

Beware of the pointer/array world in C, much confusion is around this.


Edit

Reviewing some of the other answers here, because the comment fields are too short to do there. Multiple alternatives were proposed, but it wasn't shown how they behave. Here is how they do

uint8_t (*matrix_ptr)[][20] = l_matrix;

If you fix the error and add the address-of operator & like in the following snippet

uint8_t (*matrix_ptr)[][20] = &l_matrix;

Then that one creates a pointer to an incomplete array type of elements of type array of 20 uint8_t. Because the pointer is to an array of arrays, you have to access it with

(*matrix_ptr)[0][1] = ...;

And because it's a pointer to an incomplete array, you cannot do as a shortcut

matrix_ptr[0][0][1] = ...;

Because indexing requires the element type's size to be known (indexing implies an addition of an integer to the pointer, so it won't work with incomplete types). Note that this only works in C, because T[] and T[N] are compatible types. C++ does not have a concept of compatible types, and so it will reject that code, because T[] and T[10] are different types.


The following alternative doesn't work at all, because the element type of the array, when you view it as a one-dimensional array, is not uint8_t, but uint8_t[20]

uint8_t *matrix_ptr = l_matrix; // fail

The following is a good alternative

uint8_t (*matrix_ptr)[10][20] = &l_matrix;

You access it with

(*matrix_ptr)[0][1] = ...;
matrix_ptr[0][0][1] = ...; // also possible now

It has the benefit that it preserves the outer dimension's size. So you can apply sizeof on it

sizeof (*matrix_ptr) == sizeof(uint8_t) * 10 * 20

There is one other answer that makes use of the fact that items in an array are contiguously stored

uint8_t *matrix_ptr = l_matrix[0];

Now, that formally only allows you to access the elements of the first element of the two dimensional array. That is, the following condition hold

matrix_ptr[0] = ...; // valid
matrix_ptr[19] = ...; // valid

matrix_ptr[20] = ...; // undefined behavior
matrix_ptr[10*20-1] = ...; // undefined behavior

You will notice it probably works up to 10*20-1, but if you throw on alias analysis and other aggressive optimizations, some compiler could make an assumption that may break that code. Having said that, i've never encountered a compiler that fails on it (but then again, i've not used that technique in real code), and even the C FAQ has that technique contained (with a warning about its UB'ness), and if you cannot change the array type, this is a last option to save you :)