Programs & Examples On #Restriction

What does the 'static' keyword do in a class?

Static Variables Can only be accessed only in static methods, so when we declare the static variables those getter and setter methods will be static methods

static methods is a class level we can access using class name

The following is example for Static Variables Getters And Setters:

public class Static 
{

    private static String owner;
    private static int rent;
    private String car;
    public String getCar() {
        return car;
    }
    public void setCar(String car) {
        this.car = car;
    }
    public static int getRent() {
        return rent;
    }
    public static void setRent(int rent) {
        Static.rent = rent;
    }
    public static String getOwner() {
        return owner;
    }

    public static void setOwner(String owner) {
        Static.owner = owner;
    }

}

How do I make a branch point at a specific commit?

git branch -f <branchname> <commit>

I go with Mark Longair's solution and comments and recommend anyone reads those before acting, but I'd suggest the emphasis should be on

git branch -f <branchname> <commit>

Here is a scenario where I have needed to do this.

Scenario

Develop on the wrong branch and hence need to reset it.

Start Okay

Cleanly develop and release some software.

So far so good

Develop on wrong branch

Mistake: Accidentally stay on the release branch while developing further.

After a mistake

Realize the mistake

"OH NO! I accidentally developed on the release branch." The workspace is maybe cluttered with half changed files that represent work-in-progress and we really don't want to touch and mess with. We'd just like git to flip a few pointers to keep track of the current state and put that release branch back how it should be.

Create a branch for the development that is up to date holding the work committed so far and switch to it.

git branch development
git checkout development 

Changed to another branch

Correct the branch

Now we are in the problem situation and need its solution! Rectify the mistake (of taking the release branch forward with the development) and put the release branch back how it should be.

Correct the release branch to point back to the last real release.

git branch -f release release2

The release branch is now correct again, like this ...

Corrected

What if I pushed the mistake to a remote?

git push -f <remote> <branch> is well described in another thread, though the word "overwrite" in the title is misleading. Force "git push" to overwrite remote files

what are the .map files used for in Bootstrap 3.x?

What is a CSS map file?

It is a JSON format file that links the CSS file to its source files, normally, files written in preprocessors (i.e., Less, Sass, Stylus, etc.), this is in order do a live debug to the source files from the web browser.

What is CSS preprocessor? Examples: Sass, Less, Stylus

It is a CSS generator tool that uses programming power to generate CSS robustly and quickly.

Launching Google Maps Directions via an intent on Android

This is what worked for me:

Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setData(Uri.parse("http://maps.google.co.in/maps?q=" + yourAddress));
if (intent.resolveActivity(getPackageManager()) != null) {
   startActivity(intent);
}

How to insert current datetime in postgresql insert query

You can of course format the result of current_timestamp(). Please have a look at the various formatting functions in the official documentation.

Delete files or folder recursively on Windows CMD

You can use this in the bat script:

rd /s /q "c:\folder a"

Now, just change c:\folder a to your folder's location. Quotation is only needed when your folder name contains spaces.

cannot load such file -- bundler/setup (LoadError)

Bundler Version maybe cause the issue.

Please install bundler with other version number.

For example,

gem install bundler -v 1.0.10

How to add bootstrap to an angular-cli project

Working example in case of using angular-cli and css :

1.install bootstrap

npm install bootstrap tether jquery --save

2.add to .angular-cli.json

  "styles": [
    "../node_modules/bootstrap/dist/css/bootstrap.css"
  ],
  "scripts": [
    "../node_modules/jquery/dist/jquery.js",
    "../node_modules/tether/dist/js/tether.js",
    "../node_modules/bootstrap/dist/js/bootstrap.js"
  ],

Maven: How do I activate a profile from command line?

I have encountered this problem and i solved mentioned problem by adding -DprofileIdEnabled=true parameter while running mvn cli command.

Please run your mvn cli command as : mvn clean install -Pdev1 -DprofileIdEnabled=true.

In addition to this solution, you don't need to remove activeByDefault settings in your POM mentioned as previouses answer.

I hope this answer solve your problem.

#1045 - Access denied for user 'root'@'localhost' (using password: YES)

Go to config.inc.php, find $cfg['Servers'][$i]['password'] and remove any password provided, i.e change $cfg['Servers'][$i]['password'] = 'password'; with $cfg['Servers'][$i]['password'] = '';

Now you can launch phpMyAdmin

Selecting Users menu from phpMyAdmin, select the root user and click Edit previlidges. Now scroll down to Change Password area, switch between No Password and Password to provide your new password. that's it.

Is there a simple way to delete a list element by value?

Usually Python will throw an Exception if you tell it to do something it can't so you'll have to do either:

if c in a:
    a.remove(c)

or:

try:
    a.remove(c)
except ValueError:
    pass

An Exception isn't necessarily a bad thing as long as it's one you're expecting and handle properly.

How to do a recursive find/replace of a string with awk or sed?

find /home/www \( -type d -name .git -prune \) -o -type f -print0 | xargs -0 sed -i 's/subdomainA\.example\.com/subdomainB.example.com/g'

-print0 tells find to print each of the results separated by a null character, rather than a new line. In the unlikely event that your directory has files with newlines in the names, this still lets xargs work on the correct filenames.

\( -type d -name .git -prune \) is an expression which completely skips over all directories named .git. You could easily expand it, if you use SVN or have other folders you want to preserve -- just match against more names. It's roughly equivalent to -not -path .git, but more efficient, because rather than checking every file in the directory, it skips it entirely. The -o after it is required because of how -prune actually works.

For more information, see man find.

Deadly CORS when http://localhost is the origin

Agreed! CORS should be enabled on the server-side to resolve the issue ground up. However...

For me the case was:

I desperately wanted to test my front-end(React/Angular/VUE) code locally with the REST API provided by the client with no access to the server config.

Just for testing

After trying all the steps above that didn't work I was forced to disable web security and site isolation trials on chrome along with specifying the user data directory(tried skipping this, didn't work).

For Windows

cd C:\Program Files\Google\Chrome\Application

Disable web security and site isolation trials

chrome.exe  --disable-site-isolation-trials --disable-web-security --user-data-dir="PATH_TO_PROJECT_DIRECTORY"

This finally worked! Hope this helps!

set date in input type date

Update: I'm doing this with date.toISOString().substr(0, 10). Gives the same result as the accepted answer and has good support.

How to set ssh timeout?

You could also connect with flag

-o ServerAliveInterval=<secs>
so the SSH client will send a null packet to the server each <secs> seconds, just to keep the connection alive. In Linux this could be also set globally in /etc/ssh/ssh_config or per-user in ~/.ssh/config.

How to read values from the querystring with ASP.NET Core?

I have a better solution for this problem,

  • request is a member of abstract class ControllerBase
  • GetSearchParams() is an extension method created in bellow helper class.

var searchparams = await Request.GetSearchParams();

I have created a static class with few extension methods

public static class HttpRequestExtension
{
  public static async Task<SearchParams> GetSearchParams(this HttpRequest request)
        {
            var parameters = await request.TupledParameters();

            try
            {
                for (var i = 0; i < parameters.Count; i++)
                {
                    if (parameters[i].Item1 == "_count" && parameters[i].Item2 == "0")
                    {
                        parameters[i] = new Tuple<string, string>("_summary", "count");
                    }
                }
                var searchCommand = SearchParams.FromUriParamList(parameters);
                return searchCommand;
            }
            catch (FormatException formatException)
            {
                throw new FhirException(formatException.Message, OperationOutcome.IssueType.Invalid, OperationOutcome.IssueSeverity.Fatal, HttpStatusCode.BadRequest);
            }
        }



public static async Task<List<Tuple<string, string>>> TupledParameters(this HttpRequest request)
{
        var list = new List<Tuple<string, string>>();


        var query = request.Query;
        foreach (var pair in query)
        {
            list.Add(new Tuple<string, string>(pair.Key, pair.Value));
        }

        if (!request.HasFormContentType)
        {
            return list;
        }
        var getContent = await request.ReadFormAsync();

        if (getContent == null)
        {
            return list;
        }
        foreach (var key in getContent.Keys)
        {
            if (!getContent.TryGetValue(key, out StringValues values))
            {
                continue;
            }
            foreach (var value in values)
            {
                list.Add(new Tuple<string, string>(key, value));
            }
        }
        return list;
    }
}

in this way you can easily access all your search parameters. I hope this will help many developers :)

How can I create a dynamic button click event on a dynamic button?

Button button = new Button();
button.Click += (s,e) => { your code; };
//button.Click += new EventHandler(button_Click);
container.Controls.Add(button);

//protected void button_Click (object sender, EventArgs e) { }

Typescript: No index signature with a parameter of type 'string' was found on type '{ "A": string; }

Solved similar issue by doing this:

export interface IItem extends Record<string, any> {
    itemId: string;
    price: number;
}

const item: IItem = { itemId: 'someId', price: 200 };
const fieldId = 'someid';

// gives you no errors and proper typing
item[fieldId]

Concatenating null strings in Java

You are not using the "null" and therefore you don't get the exception. If you want the NullPointer, just do

String s = null;
s = s.toString() + "hello";

And I think what you want to do is:

String s = "";
s = s + "hello";

How do I combine two data-frames based on two columns?

See the documentation on ?merge, which states:

By default the data frames are merged on the columns with names they both have, 
 but separate specifications of the columns can be given by by.x and by.y.

This clearly implies that merge will merge data frames based on more than one column. From the final example given in the documentation:

x <- data.frame(k1=c(NA,NA,3,4,5), k2=c(1,NA,NA,4,5), data=1:5)
y <- data.frame(k1=c(NA,2,NA,4,5), k2=c(NA,NA,3,4,5), data=1:5)
merge(x, y, by=c("k1","k2")) # NA's match

This example was meant to demonstrate the use of incomparables, but it illustrates merging using multiple columns as well. You can also specify separate columns in each of x and y using by.x and by.y.

Converting file into Base64String and back again

If you want for some reason to convert your file to base-64 string. Like if you want to pass it via internet, etc... you can do this

Byte[] bytes = File.ReadAllBytes("path");
String file = Convert.ToBase64String(bytes);

And correspondingly, read back to file:

Byte[] bytes = Convert.FromBase64String(b64Str);
File.WriteAllBytes(path, bytes);

Failed: Error in connection establishment: net::ERR_CONNECTION_REFUSED

Firstly, I would try a non-secure websocket connection. So remove one of the s's from the connection address:

conn = new WebSocket('ws://localhost:8080');

If that doesn't work, then the next thing I would check is your server's firewall settings. You need to open port 8080 both in TCP_IN and TCP_OUT.

How do I view cookies in Internet Explorer 11 using Developer Tools

Not quite an answer (not “using Developer Tools”), but there is a third-party tool for it: IECookiesView from NirSoft. Hope this helps someone.

screenshot

image taken from Softpedia

Regex to match only uppercase "words" with some exceptions

For the first case you propose you can use: '[[:blank:]]+[A-Z0-9]+[[:blank:]]+', for example:

echo "The thing P1 must connect to the J236 thing in the Foo position" | grep -oE '[[:blank:]]+[A-Z0-9]+[[:blank:]]+'

In the second case maybe you need to use something else and not a regex, maybe a script with a dictionary of technical words...

Cheers, Fernando

Python Checking a string's first and last character

When you set a string variable, it doesn't save quotes of it, they are a part of its definition. so you don't need to use :1

How do I resolve a HTTP 414 "Request URI too long" error?

I got this error after using $.getJSON() from JQuery. I just changed to post:

data = getDataObjectByForm(form);
var jqxhr = $.post(url, data, function(){}, 'json')
    .done(function (response) {
        if (response instanceof Object)
            var json = response;
        else
            var json = $.parseJSON(response);
        // console.log(response);
        // console.log(json);
        jsonToDom(json);
        if (json.reload != undefined && json.reload)
            location.reload();
        $("body").delay(1000).css("cursor", "default");
    })
    .fail(function (jqxhr, textStatus, error) {
        var err = textStatus + ", " + error;
        console.log("Request Failed: " + err);
        alert("Fehler!");
    });

Installing a plain plugin jar in Eclipse 3.5

Simplest way - just put in the Eclipse plugins folder. You can start Eclipse with the -clean option to make sure Eclipse cleans its' plugins cache and sees the new plugin.

In general, it is far more recommended to install plugins using proper update sites.

how to check the jdk version used to compile a .class file

Does the -verbose flag to your java command yield any useful info? If not, maybe java -X reveals something specific to your version that might help?

Copy all values from fields in one class to another through reflection

I think you can try dozer. It has good support for bean to bean conversion. Its also easy to use. You can either inject it into your spring application or add the jar in class path and its done.

For an example of your case :

 DozerMapper mapper = new DozerMapper();
A a= new A();
CopyA copyA = new CopyA();
a.set... // set fields of a.
mapper.map(a,copyOfA); // will copy all fields from a to copyA

Can someone post a well formed crossdomain.xml sample?

In production site this seems suitable:

<?xml version="1.0"?>
<cross-domain-policy>
<allow-access-from domain="www.mysite.com" />
<allow-access-from domain="mysite.com" />
</cross-domain-policy>

What's the difference between primitive and reference types?

The short answer is primitives are data types, while references are pointers, which do not hold their values but point to their values and are used on/with objects.

Primatives:

boolean

character

byte

short

integer

long

float

double

Lots of good references that explain these basic concepts. http://www.javaforstudents.co.uk/Types

Setting up a cron job in Windows

If you don't want to use Scheduled Tasks you can use the Windows Subsystem for Linux which will allow you to use cron jobs like on Linux.

To make sure cron is actually running you can type service cron status from within the Linux terminal. If it isn't currently running then type service cron start and you should be good to go.

How can I apply a function to every row/column of a matrix in MATLAB?

With recent versions of Matlab, you can use the Table data structure to your advantage. There's even a 'rowfun' operation but I found it easier just to do this:

a = magic(6);
incrementRow = cell2mat(cellfun(@(x) x+1,table2cell(table(a)),'UniformOutput',0))

or here's an older one I had that doesn't require tables, for older Matlab versions.

dataBinner = cell2mat(arrayfun(@(x) Binner(a(x,:),2)',1:size(a,1),'UniformOutput',0)')

conversion from infix to prefix

This algorithm will help you for better understanding .

Step 1. Push “)” onto STACK, and add “(“ to end of the A.

Step 2. Scan A from right to left and repeat step 3 to 6 for each element of A until the STACK is empty.

Step 3. If an operand is encountered add it to B.

Step 4. If a right parenthesis is encountered push it onto STACK.

Step 5. If an operator is encountered then: a. Repeatedly pop from STACK and add to B each operator (on the top of STACK) which has same or higher precedence than the operator. b. Add operator to STACK.

Step 6. If left parenthesis is encontered then a. Repeatedly pop from the STACK and add to B (each operator on top of stack until a left parenthesis is encounterd) b. Remove the left parenthesis.

Step 7. Exit

How to encrypt a large file in openssl using public key

Solution for safe and high secured encode anyone file in OpenSSL and command-line:

You should have ready some X.509 certificate for encrypt files in PEM format.

Encrypt file:

openssl smime -encrypt -binary -aes-256-cbc -in plainfile.zip -out encrypted.zip.enc -outform DER yourSslCertificate.pem

What is what:

  • smime - ssl command for S/MIME utility (smime(1))
  • -encrypt - chosen method for file process
  • -binary - use safe file process. Normally the input message is converted to "canonical" format as required by the S/MIME specification, this switch disable it. It is necessary for all binary files (like a images, sounds, ZIP archives).
  • -aes-256-cbc - chosen cipher AES in 256 bit for encryption (strong). If not specified 40 bit RC2 is used (very weak). (Supported ciphers)
  • -in plainfile.zip - input file name
  • -out encrypted.zip.enc - output file name
  • -outform DER - encode output file as binary. If is not specified, file is encoded by base64 and file size will be increased by 30%.
  • yourSslCertificate.pem - file name of your certificate's. That should be in PEM format.

That command can very effectively a strongly encrypt big files regardless of its format.
Known issue: Something wrong happens when you try encrypt huge file (>600MB). No error thrown, but encrypted file will be corrupted. Always verify each file! (or use PGP - that has bigger support for files encryption with public key)

Decrypt file:

openssl smime -decrypt -binary -in encrypted.zip.enc -inform DER -out decrypted.zip -inkey private.key -passin pass:your_password

What is what:

  • -inform DER - same as -outform above
  • -inkey private.key - file name of your private key. That should be in PEM format and can be encrypted by password.
  • -passin pass:your_password - your password for private key encrypt. (passphrase arguments)

How to change the font size and color of x-axis and y-axis label in a scatterplot with plot function in R?

Taking DWins example.

What I often do, particularly when I use many, many different plots with the same colours or size information, is I store them in variables I otherwise never use. This helps me keep my code a little cleaner AND I can change it "globally".

E.g.

clab = 1.5
cmain = 2
caxis = 1.2

plot(1, 1 ,xlab="x axis", ylab="y axis",  pch=19,
           col.lab="red", cex.lab=clab,    
           col="green", main = "Testing scatterplots", cex.main =cmain, cex.axis=caxis) 

You can also write a function, doing something similar. But for a quick shot this is ideal. You can also store that kind of information in an extra script, so you don't have a messy plot script:

which you then call with setwd("") source("plotcolours.r")

in a file say called plotcolours.r you then store all the e.g. colour or size variables

clab = 1.5
cmain = 2
caxis = 1.2 

for colours could use

darkred<-rgb(113,28,47,maxColorValue=255)

as your variable 'darkred' now has the colour information stored, you can access it in your actual plotting script.

plot(1,1,col=darkred) 

Click to call html

tl;dr What to do in modern (2018) times? Assume tel: is supported, use it and forget about anything else.


The tel: URI scheme RFC5431 (as well as sms: but also feed:, maps:, youtube: and others) is handled by protocol handlers (as mailto: and http: are).

They're unrelated to HTML5 specification (it has been out there from 90s and documented first time back in 2k with RFC2806) then you can't check for their support using tools as modernizr. A protocol handler may be installed by an application (for example Skype installs a callto: protocol handler with same meaning and behaviour of tel: but it's not a standard), natively supported by browser or installed (with some limitations) by website itself.

What HTML5 added is support for installing custom web based protocol handlers (with registerProtocolHandler() and related functions) simplifying also the check for their support through isProtocolHandlerRegistered() function.

There is some easy ways to determine if there is an handler or not:" How to detect browser's protocol handlers?).

In general what I suggest is:

  1. If you're running on a mobile device then you can safely assume tel: is supported (yes, it's not true for very old devices but IMO you can ignore them).
  2. If JS isn't active then do nothing.
  3. If you're running on desktop browsers then you can use one of the techniques in the linked post to determine if it's supported.
  4. If tel: isn't supported then change links to use callto: and repeat check desctibed in 3.
  5. If tel: and callto: aren't supported (or - in a desktop browser - you can't detect their support) then simply remove that link replacing URL in href with javascript:void(0) and (if number isn't repeated in text span) putting, telephone number in title. Here HTML5 microdata won't help users (just search engines). Note that newer versions of Skype handle both callto: and tel:.

Please note that (at least on latest Windows versions) there is always a - fake - registered protocol handler called App Picker (that annoying window that let you choose with which application you want to open an unknown file). This may vanish your tests so if you don't want to handle Windows environment as a special case you can simplify this process as:

  1. If you're running on a mobile device then assume tel: is supported.
  2. If you're running on desktop then replace tel: with callto:. then drop tel: or leave it as is (assuming there are good chances Skype is installed).

What, why or when it is better to choose cshtml vs aspx?

While the syntax is certainly different between Razor (.cshtml/.vbhtml) and WebForms (.aspx/.ascx), (Razor's being the more concise and modern of the two), nobody has mentioned that while both can be used as View Engines / Templating Engines, traditional ASP.NET Web Forms controls can be used on any .aspx or .ascx files, (even in cohesion with an MVC architecture).

This is relevant in situations where long standing solutions to a problem have been established and packaged into a pluggable component (e.g. a large-file uploading control) and you want to use it in an MVC site. With Razor, you can't do this. However, you can execute all of the same backend-processing that you would use with a traditional ASP.NET architecture with a Web Form view.

Furthermore, ASP.NET web forms views can have Code-Behind files, which allows embedding logic into a separate file that is compiled together with the view. While the software development community is growing to be see tightly coupled architectures and the Smart Client pattern as bad practice, it used to be the main way of doing things and is still very much possible with .aspx/.ascx files. Razor, intentionally, has no such quality.

RichTextBox (WPF) does not have string property "Text"

The WPF RichTextBox has a Document property for setting the content a la MSDN:

// Create a FlowDocument to contain content for the RichTextBox.
        FlowDocument myFlowDoc = new FlowDocument();

        // Add paragraphs to the FlowDocument.
        myFlowDoc.Blocks.Add(new Paragraph(new Run("Paragraph 1")));
        myFlowDoc.Blocks.Add(new Paragraph(new Run("Paragraph 2")));
        myFlowDoc.Blocks.Add(new Paragraph(new Run("Paragraph 3")));
        RichTextBox myRichTextBox = new RichTextBox();

        // Add initial content to the RichTextBox.
        myRichTextBox.Document = myFlowDoc;

You can just use the AppendText method though if that's all you're after.

Hope that helps.

SQL - Select first 10 rows only?

In SQL server, use:

select top 10 ...

e.g.

select top 100 * from myTable
select top 100 colA, colB from myTable

In MySQL, use:

select ... order by num desc limit 10

How to use parameters with HttpPost

To set parameters to your HttpPostRequest you can use BasicNameValuePair, something like this :

    HttpClient httpclient;
    HttpPost httpPost;
    ArrayList<NameValuePair> postParameters;
    httpclient = new DefaultHttpClient();
    httpPost = new HttpPost("your login link");


    postParameters = new ArrayList<NameValuePair>();
    postParameters.add(new BasicNameValuePair("param1", "param1_value"));
    postParameters.add(new BasicNameValuePair("param2", "param2_value"));

    httpPost.setEntity(new UrlEncodedFormEntity(postParameters, "UTF-8"));

    HttpResponse response = httpclient.execute(httpPost);

Undefined Reference to

g++ test.cpp LinearNode.cpp LinkedList.cpp -o test

Why is super.super.method(); not allowed in Java?

It would seem to be possible to at least get the class of the superclass's superclass, though not necessarily the instance of it, using reflection; if this might be useful, please consider the Javadoc at http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Class.html#getSuperclass()

How do I plot in real-time in a while loop using matplotlib?

Another option is to go with bokeh. IMO, it is a good alternative at least for real-time plots. Here is a bokeh version of the code in the question:

from bokeh.plotting import curdoc, figure
import random
import time

def update():
    global i
    temp_y = random.random()
    r.data_source.stream({'x': [i], 'y': [temp_y]})
    i += 1

i = 0
p = figure()
r = p.circle([], [])
curdoc().add_root(p)
curdoc().add_periodic_callback(update, 100)

and for running it:

pip3 install bokeh
bokeh serve --show test.py

bokeh shows the result in a web browser via websocket communications. It is especially useful when data is generated by remote headless server processes.

bokeh sample plot

Html.EditorFor Set Default Value

This worked for me

In Controlle

 ViewBag.AAA = default_Value ;

In View

@Html.EditorFor(model => model.AAA, new { htmlAttributes = new { @Value = ViewBag.AAA } }

How do I capture response of form.submit

An Ajax alternative is to set an invisible <iframe> as your form's target and read the contents of that <iframe> in its onload handler. But why bother when there's Ajax?

Note: I just wanted to mention this alternative since some of the answers claim that it's impossible to achieve this without Ajax.

How to cast Object to boolean?

Assuming that yourObject.toString() returns "true" or "false", you can try

boolean b = Boolean.valueOf(yourObject.toString())

Error - trustAnchors parameter must be non-empty

For the record, none of the answers here worked for me. My Gradle build started failing mysteriously with this error, unable to fetch HEAD from Maven central for a particular POM file.

It turned out that I had JAVA_HOME set to my own personal build of OpenJDK, which I had built for debugging a javac issue. Setting it back to the JDK installed on my system fixed it.

What is causing this error - "Fatal error: Unable to find local grunt"

Install Grunt in node_modules rather than globally

Unable to find local Grunt likely means that you have installed Grunt globally.

The Grunt CLI insists that you install grunt in your local node_modules directory, so Grunt is local to your project.

This will fail:

npm install -g grunt

Do this instead:

npm install grunt --save-dev

Render a string in HTML and preserve spaces and linebreaks

Just style the content with white-space: pre-wrap;.

_x000D_
_x000D_
div {_x000D_
    white-space: pre-wrap;_x000D_
}
_x000D_
<div>_x000D_
This is some text   with some extra spacing    and a_x000D_
few newlines along with some trailing spaces        _x000D_
     and five leading spaces thrown in_x000D_
for                                              good_x000D_
measure                                              _x000D_
</div>
_x000D_
_x000D_
_x000D_

Add a column to existing table and uniquely number them on MS SQL Server

for oracle you could do something like below

alter table mytable add (myfield integer);

update mytable set myfield = rownum;

window.open with target "_blank" in Chrome

window.open(skey, "_blank", "toolbar=1, scrollbars=1, resizable=1, width=" + 1015 + ", height=" + 800);

java comparator, how to sort by integer?

public class DogAgeComparator implements Comparator<Dog> {
    public int compare(Dog o1, Dog o2) {
        return Integer.compare(o1.getAge(), o2.getId());
    }
}

When to use <span> instead <p>?

<span> is an inline tag, a <p> is a block tag, used for paragraphs. Browsers will render a blank line below a paragraph, whereas <span>s will render on the same line.

How to create Drawable from resource

The getDrawable (int id) method is deprecated as of API 22.

Instead you should use the getDrawable (int id, Resources.Theme theme) for API 21+

Code would look something like this.

Drawable myDrawable;
if(android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP){
    myDrawable = context.getResources().getDrawable(id, context.getTheme());
} else {
    myDrawable = context.getResources().getDrawable(id);
}

C# importing class into another class doesn't work

Well what you have to "import" (use) is the namespace of MyClass not the class name itself. If both classes are in the same namespace, you don't have to "import" it.

Definition MyClass.cs

namespace Ns1
{
    public class MyClass
    {
        ...
    }
}

Usage AnotherClass.cs

using Ns1;

namespace AnotherNs
{
    public class AnotherClass
    {
        public AnotherClass()
        {
            var myInst = new MyClass();
        }
    }
}

jQuery Ajax requests are getting cancelled without being sent

In my case, I Apache's mod-rewrite was matching the url and redirecting the request to https.

Look at the request in chrome://net-internals/#events.

It will show an internal log of the request. Check for redirects.

Regular expression search replace in Sublime Text 2

Note that if you use more than 9 capture groups you have to use the syntax ${10}.

$10 or \10 or \{10} will not work.

how do I insert a column at a specific column index in pandas?

You could try to extract columns as list, massage this as you want, and reindex your dataframe:

>>> cols = df.columns.tolist()
>>> cols = [cols[-1]]+cols[:-1] # or whatever change you need
>>> df.reindex(columns=cols)

   n  l  v
0  0  a  1
1  0  b  2
2  0  c  1
3  0  d  2

EDIT: this can be done in one line ; however, this looks a bit ugly. Maybe some cleaner proposal may come...

>>> df.reindex(columns=['n']+df.columns[:-1].tolist())

   n  l  v
0  0  a  1
1  0  b  2
2  0  c  1
3  0  d  2

How do I remove repeated elements from ArrayList?

Would something like this work better ?

public static void removeDuplicates(ArrayList<String> list) {
    Arraylist<Object> ar     = new Arraylist<Object>();
    Arraylist<Object> tempAR = new Arraylist<Object>();
    while (list.size()>0){
        ar.add(list(0));
        list.removeall(Collections.singleton(list(0)));
    }
    list.addAll(ar);
}

That should maintain the order and also not be quadratic in run time.

Open terminal here in Mac OS finder

This:

https://github.com/jbtule/cdto#cd-to

It's a small app that you drag into the Finder toolbar, the icon fits in very nicely. It works with Terminal, xterm (under X11), iterm.

swift UITableView set rowHeight

As pointed out in comments, you cannot call cellForRowAtIndexPath inside heightForRowAtIndexPath.

What you can do is creating a template cell used to populate with your data and then compute its height. This cell doesn't participate to the table rendering, and it can be reused to calculate the height of each table cell.

Briefly, it consists of configuring the template cell with the data you want to display, make it resize accordingly to the content, and then read its height.

I have taken this code from a project I am working on - unfortunately it's in Objective C, I don't think you will have problems translating to swift

- (CGFloat) tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
    static PostCommentCell *sizingCell = nil;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        sizingCell = [self.tblComments dequeueReusableCellWithIdentifier:POST_COMMENT_CELL_IDENTIFIER];
    });

    sizingCell.comment = self.comments[indexPath.row];
    [sizingCell setNeedsLayout];
    [sizingCell layoutIfNeeded];

    CGSize size = [sizingCell.contentView systemLayoutSizeFittingSize:UILayoutFittingCompressedSize];
    return size.height;
}

Regular expression to match any character being repeated more than 10 times

You can also use PowerShell to quickly replace words or character reptitions. PowerShell is for Windows. Current version is 3.0.

$oldfile = "$env:windir\WindowsUpdate.log"

$newfile = "$env:temp\newfile.txt"
$text = (Get-Content -Path $oldfile -ReadCount 0) -join "`n"

$text -replace '/(.)\1{9,}/', ' ' | Set-Content -Path $newfile

call javascript function onchange event of dropdown list

Your code is working just fine, you have to declare javscript method before DOM ready.

your working example

Understanding events and event handlers in C#

//This delegate can be used to point to methods
//which return void and take a string.
public delegate void MyDelegate(string foo);

//This event can cause any method which conforms
//to MyEventHandler to be called.
public event MyDelegate MyEvent;

//Here is some code I want to be executed
//when SomethingHappened fires.
void MyEventHandler(string foo)
{
    //Do some stuff
}

//I am creating a delegate (pointer) to HandleSomethingHappened
//and adding it to SomethingHappened's list of "Event Handlers".
myObj.MyEvent += new MyDelegate (MyEventHandler);

Accessing private member variables from prototype-defined functions

You can use a prototype assignment within the constructor definition.

The variable will be visible to the prototype added method but all the instances of the functions will access the same SHARED variable.

function A()
{
  var sharedVar = 0;
  this.local = "";

  A.prototype.increment = function(lval)
  {    
    if (lval) this.local = lval;    
    alert((++sharedVar) + " while this.p is still " + this.local);
  }
}

var a = new A();
var b = new A();    
a.increment("I belong to a");
b.increment("I belong to b");
a.increment();
b.increment();

I hope this can be usefull.

Create a simple Login page using eclipse and mysql

use this code it is working

// index.jsp or login.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>

<form action="login" method="post">
Username : <input type="text" name="username"><br>
Password : <input type="password" name="pass"><br>
<input type="submit"><br>
</form>

</body>
</html>

// authentication servlet class

    import java.io.IOException;
    import java.io.PrintWriter;
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.SQLException;
    import java.sql.Statement;

    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;

    public class auth extends HttpServlet {
        private static final long serialVersionUID = 1L;

        public auth() {
            super();
        }
        protected void doGet(HttpServletRequest request,
                HttpServletResponse response) throws ServletException, IOException {

        }

        protected void doPost(HttpServletRequest request,
                HttpServletResponse response) throws ServletException, IOException {

            try {
                Class.forName("com.mysql.jdbc.Driver");
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            }

            String username = request.getParameter("username");
            String pass = request.getParameter("pass");

            String sql = "select * from reg where username='" + username + "'";
            Connection conn = null;

            try {
                conn = DriverManager.getConnection("jdbc:mysql://localhost/Exam",
                        "root", "");
                Statement s = conn.createStatement();

                java.sql.ResultSet rs = s.executeQuery(sql);
                String un = null;
                String pw = null;
                String name = null;

            /* Need to put some condition in case the above query does not return any row, else code will throw Null Pointer exception */   

            PrintWriter prwr1 = response.getWriter();               
            if(!rs.isBeforeFirst()){
                prwr1.write("<h1> No Such User in Database<h1>");
            } else {

/* Conditions to be executed after at least one row is returned by query execution */ 
                while (rs.next()) {
                    un = rs.getString("username");
                    pw = rs.getString("password");
                    name = rs.getString("name");
                }

                PrintWriter pww = response.getWriter();

                if (un.equalsIgnoreCase(username) && pw.equals(pass)) {
                                // use this or create request dispatcher 
                    response.setContentType("text/html");
                    pww.write("<h1>Welcome, " + name + "</h1>");
                } else {
                    pww.write("wrong username or password\n");
                }
              }

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

        }

    }

React Native android build failed. SDK location not found

The best solution I can find is as follows:

  1. Download Android Studio and SDK of your choice (Even if you think you don't need it trust me that you would need it to release the apk file and some manual changes to the android code).
  2. File > New > Import , point to the location where your react native android project is.
  3. If it ask you to download any specific SDK then please download the same. It can ask you to update gradle etc... Please keep on updating where required.
  4. If you have an existing Android SDK and you know the version then all you have to do is match that version under build.gradle of your android project.

This is how the gradle file will look like:

enter image description here

If everything has gone well with your machine setup and you can compile the project using the Android Studio then nothing will stop you to build your app through react-native cli build android command.

With this approach, not only you will solve the problem of SDK, you will also resolve many issues related with your machine setup for Android development. The import will automatically find SDK location and create local.properties. Hence you don't need to worry about manual interventions.

If Browser is Internet Explorer: run an alternative script instead

For IE10+ standard conditions don't work cause of engine change or some another reasons, cause, you know, it's MSIE. But for IE10+ you need to run something like this in your scripts:

if (navigator.userAgent.match(/Trident\/7\./)) {
  // do stuff for IE.
}

How To Set Text In An EditText

String string="this is a text";
editText.setText(string)

I have found String to be a useful Indirect Subclass of CharSequence

http://developer.android.com/reference/android/widget/TextView.html find setText(CharSequence text)

http://developer.android.com/reference/java/lang/CharSequence.html

Can't operator == be applied to generic types in C#?

The .Equals() works for me while TKey is a generic type.

public virtual TOutputDto GetOne(TKey id)
{
    var entity =
        _unitOfWork.BaseRepository
            .FindByCondition(x => 
                !x.IsDelete && 
                x.Id.Equals(id))
            .SingleOrDefault();


    // ...
}

Bulk Insert Correctly Quoted CSV File in SQL Server

Been stung by the same :)

I wrapped this logic into a function to clean up data that had been was already imported

DECLARE @str NVARCHAR(MAX);
DECLARE @quote_identifier NVARCHAR(MAX);

SET @quote_identifier = N'"';

SET @str = N'"quoted stuff"';

SELECT IIF(
           LEFT(@str, 1) = @quote_identifier
           AND RIGHT(@str, 1) = @quote_identifier,
           SUBSTRING(@str, DATALENGTH(@quote_identifier), LEN(@str) - DATALENGTH(@quote_identifier)),
           @str);

How can I declare dynamic String array in Java

You want to use a Set or List implementation (e.g. HashSet, TreeSet, etc, or ArrayList, LinkedList, etc..), since Java does not have dynamically sized arrays.

List<String> zoom = new ArrayList<>();
zoom.add("String 1");
zoom.add("String 2");

for (String z : zoom) {
    System.err.println(z);
}

Edit: Here is a more succinct way to initialize your List with an arbitrary number of values using varargs:

List<String> zoom = Arrays.asList("String 1", "String 2", "String n");

How to remove the left part of a string?

Another simple one-liner that hasn't been mentioned here:

value = line.split("Path=", 1)[-1]

This will also work properly for various edge cases:

>>> print("prefixfoobar".split("foo", 1)[-1])
"bar"

>>> print("foofoobar".split("foo", 1)[-1])
"foobar"

>>> print("foobar".split("foo", 1)[-1])
"bar"

>>> print("bar".split("foo", 1)[-1])
"bar"

>>> print("".split("foo", 1)[-1])
""

Service has zero application (non-infrastructure) endpoints

The endpoint should also have the namespace:

 <endpoint address="uri" binding="wsHttpBinding" contract="Namespace.Interface" />

Recursion in Python? RuntimeError: maximum recursion depth exceeded while calling a Python object

Python lacks the tail recursion optimizations common in functional languages like lisp. In Python, recursion is limited to 999 calls (see sys.getrecursionlimit).

If 999 depth is more than you are expecting, check if the implementation lacks a condition that stops recursion, or if this test may be wrong for some cases.

I dare to say that in Python, pure recursive algorithm implementations are not correct/safe. A fib() implementation limited to 999 is not really correct. It is always possible to convert recursive into iterative, and doing so is trivial.

It is not reached often because in many recursive algorithms the depth tend to be logarithmic. If it is not the case with your algorithm and you expect recursion deeper than 999 calls you have two options:

1) You can change the recursion limit with sys.setrecursionlimit(n) until the maximum allowed for your platform:

sys.setrecursionlimit(limit):

Set the maximum depth of the Python interpreter stack to limit. This limit prevents infinite recursion from causing an overflow of the C stack and crashing Python.

The highest possible limit is platform-dependent. A user may need to set the limit higher when she has a program that requires deep recursion and a platform that supports a higher limit. This should be done with care, because a too-high limit can lead to a crash.

2) You can try to convert the algorithm from recursive to iterative. If recursion depth is bigger than allowed by your platform, it is the only way to fix the problem. There are step by step instructions on the Internet and it should be a straightforward operation for someone with some CS education. If you are having trouble with that, post a new question so we can help.

setTimeout / clearTimeout problems

Not sure if this violates some good practice coding rule but I usually come out with this one:

if(typeof __t == 'undefined')
        __t = 0;
clearTimeout(__t);
__t = setTimeout(callback, 1000);

This prevent the need to declare the timer out of the function.

EDIT: this also don't declare a new variable at each invocation, but always recycle the same.

Hope this helps.

In UML class diagrams, what are Boundary Classes, Control Classes, and Entity Classes?

Robustness diagrams are written after use cases and before class diagrams. They help to identify the roles of use case steps. You can use them to ensure your use cases are sufficiently robust to represent usage requirements for the system you're building.

They involve:

  1. Actors
  2. Use Cases
  3. Entities
  4. Boundaries
  5. Controls

Whereas the Model-View-Controller pattern is used for user interfaces, the Entity-Control-Boundary Pattern (ECB) is used for systems. The following aspects of ECB can be likened to an abstract version of MVC, if that's helpful:

UML notation

Entities (model)
Objects representing system data, often from the domain model.

Boundaries (view/service collaborator)
Objects that interface with system actors (e.g. a user or external service). Windows, screens and menus are examples of boundaries that interface with users.

Controls (controller)
Objects that mediate between boundaries and entities. These serve as the glue between boundary elements and entity elements, implementing the logic required to manage the various elements and their interactions. It is important to understand that you may decide to implement controllers within your design as something other than objects – many controllers are simple enough to be implemented as a method of an entity or boundary class for example.

Four rules apply to their communication:

  1. Actors can only talk to boundary objects.
  2. Boundary objects can only talk to controllers and actors.
  3. Entity objects can only talk to controllers.
  4. Controllers can talk to boundary objects and entity objects, and to other controllers, but not to actors

Communication allowed:

         Entity    Boundary   Control
Entity     X                     X
Boundary                         X
Control    X          X          X

How to get temporary folder for current user

try

Environment.GetEnvironmentVariable("temp");

Checking if a number is an Integer in Java

if you're talking floating point values, you have to be very careful due to the nature of the format.

the best way that i know of doing this is deciding on some epsilon value, say, 0.000001f, and then doing something like this:

boolean nearZero(float f)
{
    return ((-episilon < f) && (f <epsilon)); 
}

then

if(nearZero(z-(int)z))
{ 
    //do stuff
}

essentially you're checking to see if z and the integer case of z have the same magnitude within some tolerance. This is necessary because floating are inherently imprecise.

NOTE, HOWEVER: this will probably break if your floats have magnitude greater than Integer.MAX_VALUE (2147483647), and you should be aware that it is by necessity impossible to check for integral-ness on floats above that value.

Java: using switch statement with enum under subclass

Write someMethod() in this way:

public void someMethod() {

    SomeClass.AnotherClass.MyEnum enumExample = SomeClass.AnotherClass.MyEnum.VALUE_A;

    switch (enumExample) {
    case VALUE_A:
        break;
    }

}

In switch statement you must use the constant name only.

How to set a Javascript object values dynamically?

myObj[prop] = value;

That should work. You mixed up the name of the variable and its value. But indexing an object with strings to get at its properties works fine in JavaScript.

Use of *args and **kwargs

The syntax is the * and **. The names *args and **kwargs are only by convention but there's no hard requirement to use them.

You would use *args when you're not sure how many arguments might be passed to your function, i.e. it allows you pass an arbitrary number of arguments to your function. For example:

>>> def print_everything(*args):
        for count, thing in enumerate(args):
...         print( '{0}. {1}'.format(count, thing))
...
>>> print_everything('apple', 'banana', 'cabbage')
0. apple
1. banana
2. cabbage

Similarly, **kwargs allows you to handle named arguments that you have not defined in advance:

>>> def table_things(**kwargs):
...     for name, value in kwargs.items():
...         print( '{0} = {1}'.format(name, value))
...
>>> table_things(apple = 'fruit', cabbage = 'vegetable')
cabbage = vegetable
apple = fruit

You can use these along with named arguments too. The explicit arguments get values first and then everything else is passed to *args and **kwargs. The named arguments come first in the list. For example:

def table_things(titlestring, **kwargs)

You can also use both in the same function definition but *args must occur before **kwargs.

You can also use the * and ** syntax when calling a function. For example:

>>> def print_three_things(a, b, c):
...     print( 'a = {0}, b = {1}, c = {2}'.format(a,b,c))
...
>>> mylist = ['aardvark', 'baboon', 'cat']
>>> print_three_things(*mylist)
a = aardvark, b = baboon, c = cat

As you can see in this case it takes the list (or tuple) of items and unpacks it. By this it matches them to the arguments in the function. Of course, you could have a * both in the function definition and in the function call.

Will iOS launch my app into the background if it was force-quit by the user?

This might help you

In most cases, the system does not relaunch apps after they are force quit by the user. One exception is location apps, which in iOS 8 and later are relaunched after being force quit by the user. In other cases, though, the user must launch the app explicitly or reboot the device before the app can be launched automatically into the background by the system. When password protection is enabled on the device, the system does not launch an app in the background before the user first unlocks the device.

Source: https://developer.apple.com/library/content/documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/BackgroundExecution/BackgroundExecution.html

The most efficient way to remove first N elements in a list?

Python lists were not made to operate on the beginning of the list and are very ineffective at this operation.

While you can write

mylist = [1, 2 ,3 ,4]
mylist.pop(0)

It's very inefficient.


If you only want to delete items from your list, you can do this with del:

del mylist[:n]

Which is also really fast:

In [34]: %%timeit
help=range(10000)
while help:
    del help[:1000]
   ....:
10000 loops, best of 3: 161 µs per loop

If you need to obtain elements from the beginning of the list, you should use collections.deque by Raymond Hettinger and its popleft() method.

from collections import deque

deque(['f', 'g', 'h', 'i', 'j'])

>>> d.pop()                          # return and remove the rightmost item
'j'
>>> d.popleft()                      # return and remove the leftmost item
'f'

A comparison:

list + pop(0)

In [30]: %%timeit
   ....: help=range(10000)
   ....: while help:
   ....:     help.pop(0)
   ....:
100 loops, best of 3: 17.9 ms per loop

deque + popleft()

In [33]: %%timeit
help=deque(range(10000))
while help:
    help.popleft()
   ....:
1000 loops, best of 3: 812 µs per loop

Setting default values for columns in JPA

Actually it is possible in JPA, although a little bit of a hack using the columnDefinition property of the @Column annotation, for example:

@Column(name="Price", columnDefinition="Decimal(10,2) default '100.00'")

How to check is Apache2 is stopped in Ubuntu?

In the command line type service apache2 status then hit enter. The result should say:

Apache2 is running (pid xxxx)

How do I make a list of data frames?

If you have a large number of sequentially named data frames you can create a list of the desired subset of data frames like this:

d1 <- data.frame(y1=c(1,2,3), y2=c(4,5,6))
d2 <- data.frame(y1=c(3,2,1), y2=c(6,5,4))
d3 <- data.frame(y1=c(6,5,4), y2=c(3,2,1))
d4 <- data.frame(y1=c(9,9,9), y2=c(8,8,8))

my.list <- list(d1, d2, d3, d4)
my.list

my.list2 <- lapply(paste('d', seq(2,4,1), sep=''), get)
my.list2

where my.list2 returns a list containing the 2nd, 3rd and 4th data frames.

[[1]]
  y1 y2
1  3  6
2  2  5
3  1  4

[[2]]
  y1 y2
1  6  3
2  5  2
3  4  1

[[3]]
  y1 y2
1  9  8
2  9  8
3  9  8

Note, however, that the data frames in the above list are no longer named. If you want to create a list containing a subset of data frames and want to preserve their names you can try this:

list.function <-  function() { 

     d1 <- data.frame(y1=c(1,2,3), y2=c(4,5,6))
     d2 <- data.frame(y1=c(3,2,1), y2=c(6,5,4))
     d3 <- data.frame(y1=c(6,5,4), y2=c(3,2,1))
     d4 <- data.frame(y1=c(9,9,9), y2=c(8,8,8))

     sapply(paste('d', seq(2,4,1), sep=''), get, environment(), simplify = FALSE) 
} 

my.list3 <- list.function()
my.list3

which returns:

> my.list3
$d2
  y1 y2
1  3  6
2  2  5
3  1  4

$d3
  y1 y2
1  6  3
2  5  2
3  4  1

$d4
  y1 y2
1  9  8
2  9  8
3  9  8

> str(my.list3)
List of 3
 $ d2:'data.frame':     3 obs. of  2 variables:
  ..$ y1: num [1:3] 3 2 1
  ..$ y2: num [1:3] 6 5 4
 $ d3:'data.frame':     3 obs. of  2 variables:
  ..$ y1: num [1:3] 6 5 4
  ..$ y2: num [1:3] 3 2 1
 $ d4:'data.frame':     3 obs. of  2 variables:
  ..$ y1: num [1:3] 9 9 9
  ..$ y2: num [1:3] 8 8 8

> my.list3[[1]]
  y1 y2
1  3  6
2  2  5
3  1  4

> my.list3$d4
  y1 y2
1  9  8
2  9  8
3  9  8

String Array object in Java

public static void main(String[] args) {

        public String[] name = {"Art", "Dan", "Jen"};
        public String[] country = {"Canada", "Germant", "USA"};
        // initialize your performance array here too.

        //Your constructor takes arrays as an argument so you need to be sure to pass in the arrays and not just objects.
        Athlete art = new Athlete(name, country, performance);   

}

How to count the number of occurrences of a character in an Oracle varchar value?

here is a solution that will function for both characters and substrings:

select (length('a') - nvl(length(replace('a','b')),0)) / length('b')
  from dual

where a is the string in which you search the occurrence of b

have a nice day!

MemoryStream - Cannot access a closed Stream

Since .net45 you can use the LeaveOpen constructor argument of StreamWriter and still use the using statement. Example:

using (var ms = new MemoryStream())
{
    using (var sw = new StreamWriter(ms, Encoding.UTF8, 1024, true))
    {
        sw.WriteLine("data");
        sw.WriteLine("data 2");    
    }

    ms.Position = 0;
    using (var sr = new StreamReader(ms))
    {
        Console.WriteLine(sr.ReadToEnd());
    }
}

Java - How to convert type collection into ArrayList?

More information needed for a definitive answer, but this code

myNodeList = (ArrayList<MyNode>)this.getVertices();

will only work if this.getVertices() returns a (subtype of) List<MyNode>. If it is a different collection (like your Exception seems to indicate), you want to use

new ArrayList<MyNode>(this.getVertices())

This will work as long as a Collection type is returned by getVertices.

How does Java resolve a relative path in new File()?

On windows and Netbeans you can set the relative path as:

    new FileReader("src\\PACKAGE_NAME\\FILENAME");

On Linux and Netbeans you can set the relative path as:

    new FileReader("src/PACKAGE_NAME/FILENAME");

If you have your code inside Source Packages I do not know if it is the same for eclipse or other IDE

maven... Failed to clean project: Failed to delete ..\org.ow2.util.asm-asm-tree-3.1.jar

Please close all the browser tab. And next time when you try to upload war from another place except target folder.

Print "\n" or newline characters as part of the output on terminal

Use repr

>>> string = "abcd\n"
>>> print(repr(string))
'abcd\n'

What is the difference between window, screen, and document in Javascript?

The window is the first thing that gets loaded into the browser. This window object has the majority of the properties like length, innerWidth, innerHeight, name, if it has been closed, its parents, and more.

The document object is your html, aspx, php, or other document that will be loaded into the browser. The document actually gets loaded inside the window object and has properties available to it like title, URL, cookie, etc. What does this really mean? That means if you want to access a property for the window it is window.property, if it is document it is window.document.property which is also available in short as document.property.

How to set max and min value for Y axis

The above answers didn't work for me. Possibly the option names were changed since '11, but the following did the trick for me:

ChartJsProvider.setOptions
  scaleBeginAtZero: true

Apache VirtualHost 403 Forbidden

Apache 2.4.3 (or maybe slightly earlier) added a new security feature that often results in this error. You would also see a log message of the form "client denied by server configuration". The feature is requiring a user identity to access a directory. It is turned on by DEFAULT in the httpd.conf that ships with Apache. You can see the enabling of the feature with the directive

Require all denied

This basically says to deny access to all users. To fix this problem, either remove the denied directive (or much better) add the following directive to the directories you want to grant access to:

Require all granted

as in

<Directory "your directory here">
   Order allow,deny
   Allow from all
   # New directive needed in Apache 2.4.3: 
   Require all granted
</Directory>

Find (and kill) process locking port 3000 on Mac

To view the processes blocking the port:

netstat -vanp tcp | grep 3000

To Kill the processes blocking the port:

kill $(lsof -t -i :3000)

INSTALL_FAILED_DUPLICATE_PERMISSION... C2D_MESSAGE

See this link it said that it will work when they are signed by the same key. The release key and the debug key are not the same.

So do it:

buildTypes {
        release {
            minifyEnabled true
            signingConfig signingConfigs.release//signing by the same key
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-android.txt'

        }
        debug {
            applicationIdSuffix ".debug"
            debuggable true
            signingConfig signingConfigs.release//signing by the same key
        }

    }

 signingConfigs {
        release {
            storeFile file("***\\key_.jks")
            storePassword "key_***"
            keyAlias "key_***"
            keyPassword "key_"***"
        }


}

CSS last-child selector: select last-element of specific class, not last child inside of parent?

:last-child only works when the element in question is the last child of the container, not the last of a specific type of element. For that, you want :last-of-type

http://jsfiddle.net/C23g6/3/

As per @BoltClock's comment, this is only checking for the last article element, not the last element with the class of .comment.

_x000D_
_x000D_
body {_x000D_
  background: black;_x000D_
}_x000D_
_x000D_
.comment {_x000D_
  width: 470px;_x000D_
  border-bottom: 1px dotted #f0f0f0;_x000D_
  margin-bottom: 10px;_x000D_
}_x000D_
_x000D_
.comment:last-of-type {_x000D_
  border-bottom: none;_x000D_
  margin-bottom: 0;_x000D_
}
_x000D_
<div class="commentList">_x000D_
  <article class="comment " id="com21"></article>_x000D_
_x000D_
  <article class="comment " id="com20"></article>_x000D_
_x000D_
  <article class="comment " id="com19"></article>_x000D_
_x000D_
  <div class="something"> hello </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Entity Framework Timeouts

Usually I handle my operations within a transaction. As I've experienced, it is not enough to set the context command timeout, but the transaction needs a constructor with a timeout parameter. I had to set both time out values for it to work properly.

int? prevto = uow.Context.Database.CommandTimeout;
uow.Context.Database.CommandTimeout = 900;
using (TransactionScope scope = new TransactionScope(TransactionScopeOption.Required, TimeSpan.FromSeconds(900))) {
...
}

At the end of the function I set back the command timeout to the previous value in prevto.

Using EF6

How do I run a docker instance from a DockerFile?

Download the file and from the same directory run docker build -t nodebb .

This will give you an image on your local machine that's named nodebb that you can launch an container from with docker run -d nodebb (you can change nodebb to your own name).

Python: Append item to list N times

You could do this with a list comprehension

l = [x for i in range(10)];

How can I manually set an Angular form field as invalid?

I was trying to call setErrors() inside a ngModelChange handler in a template form. It did not work until I waited one tick with setTimeout():

template:

<input type="password" [(ngModel)]="user.password" class="form-control" 
 id="password" name="password" required (ngModelChange)="checkPasswords()">

<input type="password" [(ngModel)]="pwConfirm" class="form-control"
 id="pwConfirm" name="pwConfirm" required (ngModelChange)="checkPasswords()"
 #pwConfirmModel="ngModel">

<div [hidden]="pwConfirmModel.valid || pwConfirmModel.pristine" class="alert-danger">
   Passwords do not match
</div>

component:

@ViewChild('pwConfirmModel') pwConfirmModel: NgModel;

checkPasswords() {
  if (this.pwConfirm.length >= this.user.password.length &&
      this.pwConfirm !== this.user.password) {
    console.log('passwords do not match');
    // setErrors() must be called after change detection runs
    setTimeout(() => this.pwConfirmModel.control.setErrors({'nomatch': true}) );
  } else {
    // to clear the error, we don't have to wait
    this.pwConfirmModel.control.setErrors(null);
  }
}

Gotchas like this are making me prefer reactive forms.

How to remove the focus from a TextBox in WinForms?

It seems that I don't have to set the focus to any other elements. On a Windows Phone 7 application, I've been using the Focus method to unset the Focus of a Textbox.

Giving the following command will set the focus to nothing:

void SearchBox_KeyDown(object sender, System.Windows.Input.KeyEventArgs e)
{
    if (e.Key == Key.Enter)
    {
        Focus();
    }
}

http://msdn.microsoft.com/en-us/library/system.windows.forms.control.focus.aspx

It worked for me, but I don't know why didn't it work for you :/

jquery find closest previous sibling with class

I think all the answers are lacking something. I prefer using something like this

$('li.current_sub').prevUntil("li.par_cat").prev();

Saves you not adding :first inside the selector and is easier to read and understand. prevUntil() method has a better performance as well rather than using prevAll()

How to check cordova android version of a cordova/phonegap project?

Run

cordova -v 

to see the currently running version. Run the npm info command

npm info cordova

for a longer listing that includes the current version along with other available version numbers

Atom menu is missing. How do I re-enable

Open Atom and press ALT key you are done.

Android Recyclerview GridLayoutManager column spacing

RecyclerViews support the concept of ItemDecoration: special offsets and drawing around each element. As seen in this answer, you can use

public class SpacesItemDecoration extends RecyclerView.ItemDecoration {
  private int space;

  public SpacesItemDecoration(int space) {
    this.space = space;
  }

  @Override
  public void getItemOffsets(Rect outRect, View view, 
      RecyclerView parent, RecyclerView.State state) {
    outRect.left = space;
    outRect.right = space;
    outRect.bottom = space;

    // Add top margin only for the first item to avoid double space between items
    if (parent.getChildLayoutPosition(view) == 0) {
        outRect.top = space;
    } else {
        outRect.top = 0;
    }
  }
}

Then add it via

mRecyclerView = (RecyclerView) rootView.findViewById(R.id.my_recycler_view);
int spacingInPixels = getResources().getDimensionPixelSize(R.dimen.spacing);
mRecyclerView.addItemDecoration(new SpacesItemDecoration(spacingInPixels));

How to get PHP $_GET array?

You can specify an array in your HTML this way:

<input type="hidden" name="id[]" value="1"/>
<input type="hidden" name="id[]" value="2"/>
<input type="hidden" name="id[]" value="3"/>

This will result in this $_GET array in PHP:

array(
  'id' => array(
    0 => 1,
    1 => 2,
    2 => 3
  )
)

Of course, you can use any sort of HTML input, here. The important thing is that all inputs whose values you want in the 'id' array have the name id[].

Different font size of strings in the same TextView

Use a Spannable String

 String s= "Hello Everyone";
 SpannableString ss1=  new SpannableString(s);
 ss1.setSpan(new RelativeSizeSpan(2f), 0,5, 0); // set size
 ss1.setSpan(new ForegroundColorSpan(Color.RED), 0, 5, 0);// set color
 TextView tv= (TextView) findViewById(R.id.textview);
 tv.setText(ss1); 

Snap shot

enter image description here

You can split string using space and add span to the string you require.

 String s= "Hello Everyone";  
 String[] each = s.split(" ");

Now apply span to the string and add the same to textview.

Installing OpenCV on Windows 7 for Python 2.7

As of OpenCV 2.2.0, the package name for the Python bindings is "cv".The old bindings named "opencv" are not maintained any longer. You might have to adjust your code. See http://opencv.willowgarage.com/wiki/PythonInterface.

The official OpenCV installer does not install the Python bindings into your Python directory. There should be a Python2.7 directory inside your OpenCV 2.2.0 installation directory. Copy the whole Lib folder from OpenCV\Python2.7\ to C:\Python27\ and make sure your OpenCV\bin directory is in the Windows DLL search path.

Alternatively use the opencv-python installers at http://www.lfd.uci.edu/~gohlke/pythonlibs/#opencv.

How to fix warning from date() in PHP"

error_reporting(E_ALL ^ E_WARNING);

:)

You should change subject to "How to fix warning from date() in PHP"...

Undoing a git rebase

Let's say I rebase master to my feature branch and I get 30 new commits which break something. I've found that often it's easiest to just remove the bad commits.

git rebase -i HEAD~31

Interactive rebase for the last 31 commits (it doesn't hurt if you pick way too many).

Simply take the commits that you want to get rid of and mark them with "d" instead of "pick". Now the commits are deleted effectively undoing the rebase (if you remove only the commits you just got when rebasing).

Import Error: No module named numpy

Installing Numpy on Windows

  1. Open Windows command prompt with administrator privileges (quick method: Press the Windows key. Type "cmd". Right-click on the suggested "Command Prompt" and select "Run as Administrator)
  2. Navigate to the Python installation directory's Scripts folder using the "cd" (change directory) command. e.g. "cd C:\Program Files (x86)\PythonXX\Scripts"

This might be: C:\Users\\AppData\Local\Programs\Python\PythonXX\Scripts or C:\Program Files (x86)\PythonXX\Scripts (where XX represents the Python version number), depending on where it was installed. It may be easier to find the folder using Windows explorer, and then paste or type the address from the Explorer address bar into the command prompt.

  1. Enter the following command: "pip install numpy".

You should see something similar to the following text appear as the package is downloaded and installed.

Collecting numpy
  Downloading numpy-1.13.3-2-cp27-none-win32.whl (6.7MB)  
  100% |################################| 6.7MB 112kB/s
Installing collected packages: numpy
Successfully installed numpy-1.13.3

How to use "like" and "not like" in SQL MSAccess for the same field?

What I found out is that MS Access will reject --Not Like "BB*"-- if not enclosed in PARENTHESES, unlike --Like "BB*"-- which is ok without parentheses.

I tested these on MS Access 2010 and are all valid:

  1. Like "BB"

  2. (Like "BB")

  3. (Not Like "BB")

Remove the newline character in a list read from a file

str.strip() returns a string with leading+trailing whitespace removed, .lstrip and .rstrip for only leading and trailing respectively.

grades.append(lists[i].rstrip('\n').split(','))

How to determine if a decimal/double is an integer?

For floating point numbers, n % 1 == 0 is typically the way to check if there is anything past the decimal point.

public static void Main (string[] args)
{
    decimal d = 3.1M;
    Console.WriteLine((d % 1) == 0);
    d = 3.0M;
    Console.WriteLine((d % 1) == 0);
}

Output:

False
True

Update: As @Adrian Lopez mentioned below, comparison with a small value epsilon will discard floating-point computation mis-calculations. Since the question is about double values, below will be a more floating-point calculation proof answer:

Math.Abs(d % 1) <= (Double.Epsilon * 100)

How to read appSettings section in the web.config file?

You should add System.configuration dll as reference and use System.Configuration.ConfigurationManager.AppSettings["configFile"].ToString

Don't forget to add usingstatement at the beginning. Hope it will help.

How can you print a variable name in python?

You can't, as there are no variables in Python but only names.

For example:

> a = [1,2,3]
> b = a
> a is b
True

Which of those two is now the correct variable? There's no difference between a and b.

There's been a similar question before.

Error Code 1292 - Truncated incorrect DOUBLE value - Mysql

When I received this error I believe it was a bug, however you should keep in mind that if you do a separate query with a SELECT statement and the same WHERE clause, then you can grab the primary ID's from that SELECT: SELECT CONCAT(primary_id, ',')) statement and insert them into the failed UPDATE query with conditions -> "WHERE [primary_id] IN ([list of comma-separated primary ID's from the SELECT statement)" which allows you to alleviate any issues being caused by the original (failed) query's WHERE clause.

For me, personally, when I was using quotes for the values in the "WHERE ____ IN ([values here])", only 10 of the 300 expected entries were being affected which, in my opinion, seems like a bug.

CSS to select/style first word

There isn't a plain CSS method for this. You might have to go with JavaScript + Regex to pop in a span.

Ideally, there would be a pseudo-element for first-word, but you're out of luck as that doesn't appear to work. We do have :first-letter and :first-line.

You might be able to use a combination of :after or :before to get at it without using a span.

Splitting string with pipe character ("|")

| is a metacharacter in regex. You'd need to escape it:

String[] value_split = rat_values.split("\\|");

Super-simple example of C# observer/observable with delegates

Applying the Observer Pattern with delegates and events in c# is named "Event Pattern" according to MSDN which is a slight variation.

In this Article you will find well structured examples of how to apply the pattern in c# both the classic way and using delegates and events.

Exploring the Observer Design Pattern

public class Stock
{

    //declare a delegate for the event
    public delegate void AskPriceChangedHandler(object sender,
          AskPriceChangedEventArgs e);
    //declare the event using the delegate
    public event AskPriceChangedHandler AskPriceChanged;

    //instance variable for ask price
    object _askPrice;

    //property for ask price
    public object AskPrice
    {

        set
        {
            //set the instance variable
            _askPrice = value;

            //fire the event
            OnAskPriceChanged();
        }

    }//AskPrice property

    //method to fire event delegate with proper name
    protected void OnAskPriceChanged()
    {

        AskPriceChanged(this, new AskPriceChangedEventArgs(_askPrice));

    }//AskPriceChanged

}//Stock class

//specialized event class for the askpricechanged event
public class AskPriceChangedEventArgs : EventArgs
{

    //instance variable to store the ask price
    private object _askPrice;

    //constructor that sets askprice
    public AskPriceChangedEventArgs(object askPrice) { _askPrice = askPrice; }

    //public property for the ask price
    public object AskPrice { get { return _askPrice; } }

}//AskPriceChangedEventArgs

Difference between variable declaration syntaxes in Javascript (including global variables)?

Bassed on the excellent answer of T.J. Crowder: (Off-topic: Avoid cluttering window)

This is an example of his idea:

Html

<!DOCTYPE html>
<html>
  <head>
    <script type="text/javascript" src="init.js"></script>
    <script type="text/javascript">
      MYLIBRARY.init(["firstValue", 2, "thirdValue"]);
    </script>
    <script src="script.js"></script>
  </head>

  <body>
    <h1>Hello !</h1>
  </body>    
</html>

init.js (Based on this answer)

var MYLIBRARY = MYLIBRARY || (function(){
    var _args = {}; // private

    return {
        init : function(Args) {
            _args = Args;
            // some other initialising
        },
        helloWorld : function(i) {
            return _args[i];
        }
    };
}());

script.js

// Here you can use the values defined in the html as if it were a global variable
var a = "Hello World " + MYLIBRARY.helloWorld(2);

alert(a);

Here's the plnkr. Hope it help !

Powershell: convert string to number

It seems the issue is in "-f ($_.Partition.Size/1GB)}}" If you want the value in MB then change the 1GB to 1MB.

Error 330 (net::ERR_CONTENT_DECODING_FAILED):

I had a bit of a dummy moment this morning when I realized what caused this issue for me.

The strange thing is that the request was failing in both Firefox and Chrome, but worked when I tried to access via Fiddler Web Debugger.

For me, the problem was I had mis-typed a character into one of the PHP files in the project. I didn't notice this until I checked Git for changes to the project.

In my case I had: m<?php runMyProgram(); ?>.

Once I erased the m, it started working again.

Using JSON POST Request

An example using jQuery is below. Hope this helps

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<title>My jQuery JSON Web Page</title>
<head>
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
<script type="text/javascript">

JSONTest = function() {

    var resultDiv = $("#resultDivContainer");

    $.ajax({
        url: "https://example.com/api/",
        type: "POST",
        data: { apiKey: "23462", method: "example", ip: "208.74.35.5" },
        dataType: "json",
        success: function (result) {
            switch (result) {
                case true:
                    processResponse(result);
                    break;
                default:
                    resultDiv.html(result);
            }
        },
        error: function (xhr, ajaxOptions, thrownError) {
        alert(xhr.status);
        alert(thrownError);
        }
    });
};

</script>
</head>
<body>

<h1>My jQuery JSON Web Page</h1>

<div id="resultDivContainer"></div>

<button type="button" onclick="JSONTest()">JSON</button>

</body>
</html> 

Firebug debug process

Firebug XHR debug process

Definition of int64_t

My 2 cents, from a current implementation Point of View and for SWIG users on k8 (x86_64) architecture.

Linux

First long long and long int are different types but sizeof(long long) == sizeof(long int) == sizeof(int64_t)

Gcc

First try to find where and how the compiler define int64_t and uint64_t

grepc -rn "typedef.*INT64_TYPE" /lib/gcc
/lib/gcc/x86_64-linux-gnu/9/include/stdint-gcc.h:43:typedef __INT64_TYPE__ int64_t;
/lib/gcc/x86_64-linux-gnu/9/include/stdint-gcc.h:55:typedef __UINT64_TYPE__ uint64_t;

So we need to find this compiler macro definition

gcc -dM -E -x c /dev/null | grep __INT64                 
#define __INT64_C(c) c ## L
#define __INT64_MAX__ 0x7fffffffffffffffL
#define __INT64_TYPE__ long int

gcc -dM -E -x c++ /dev/null | grep __INT64
#define __INT64_C(c) c ## L
#define __INT64_MAX__ 0x7fffffffffffffffL
#define __INT64_TYPE__ long int

Clang

clang -dM -E -x c++ /dev/null | grep INT64_TYPE
#define __INT64_TYPE__ long int
#define __UINT64_TYPE__ long unsigned int

Clang, GNU compilers:
-dM dumps a list of macros.
-E prints results to stdout instead of a file.
-x c and -x c++ select the programming language when using a file without a filename extension, such as /dev/null

Ref: https://web.archive.org/web/20190803041507/http://nadeausoftware.com/articles/2011/12/c_c_tip_how_list_compiler_predefined_macros

note: for swig user, on Linux x86_64 use -DSWIGWORDSIZE64

MacOS

On Catalina 10.15 IIRC

Clang

clang -dM -E -x c++ /dev/null | grep INT64_TYPE
#define __INT64_TYPE__ long long int
#define __UINT64_TYPE__ long long unsigned int

Clang:
-dM dumps a list of macros.
-E prints results to stdout instead of a file.
-x c and -x c++ select the programming language when using a file without a filename extension, such as /dev/null

Ref: https://web.archive.org/web/20190803041507/http://nadeausoftware.com/articles/2011/12/c_c_tip_how_list_compiler_predefined_macros

note: for swig user, on macOS x86_64 don't use -DSWIGWORDSIZE64

Visual Studio 2019

First sizeof(long int) == 4 and sizeof(long long) == 8

in stdint.h we have:

#if _VCRT_COMPILER_PREPROCESSOR

typedef signed char        int8_t;
typedef short              int16_t;
typedef int                int32_t;
typedef long long          int64_t;
typedef unsigned char      uint8_t;
typedef unsigned short     uint16_t;
typedef unsigned int       uint32_t;
typedef unsigned long long uint64_t;

note: for swig user, on windows x86_64 don't use -DSWIGWORDSIZE64

SWIG Stuff

First see https://github.com/swig/swig/blob/3a329566f8ae6210a610012ecd60f6455229fe77/Lib/stdint.i#L20-L24 so you can control the typedef using SWIGWORDSIZE64 but...

now the bad: SWIG Java and SWIG CSHARP do not take it into account

So you may want to use

#if defined(SWIGJAVA)
#if defined(SWIGWORDSIZE64)
%define PRIMITIVE_TYPEMAP(NEW_TYPE, TYPE)
%clear NEW_TYPE;
%clear NEW_TYPE *;
%clear NEW_TYPE &;
%clear const NEW_TYPE &;
%apply TYPE { NEW_TYPE };
%apply TYPE * { NEW_TYPE * };
%apply TYPE & { NEW_TYPE & };
%apply const TYPE & { const NEW_TYPE & };
%enddef // PRIMITIVE_TYPEMAP
PRIMITIVE_TYPEMAP(long int, long long);
PRIMITIVE_TYPEMAP(unsigned long int, long long);
#undef PRIMITIVE_TYPEMAP
#endif // defined(SWIGWORDSIZE64)
#endif // defined(SWIGJAVA)

and

#if defined(SWIGCSHARP)
#if defined(SWIGWORDSIZE64)
%define PRIMITIVE_TYPEMAP(NEW_TYPE, TYPE)
%clear NEW_TYPE;
%clear NEW_TYPE *;
%clear NEW_TYPE &;
%clear const NEW_TYPE &;
%apply TYPE { NEW_TYPE };
%apply TYPE * { NEW_TYPE * };
%apply TYPE & { NEW_TYPE & };
%apply const TYPE & { const NEW_TYPE & };
%enddef // PRIMITIVE_TYPEMAP
PRIMITIVE_TYPEMAP(long int, long long);
PRIMITIVE_TYPEMAP(unsigned long int, unsigned long long);
#undef PRIMITIVE_TYPEMAP
#endif // defined(SWIGWORDSIZE64)
#endif // defined(SWIGCSHARP)

So int64_t aka long int will be bind to Java/C# long on Linux...

dyld: Library not loaded ... Reason: Image not found

If you are using Conda environment in the terminal, update the samtools to solve it.

conda install -c bioconda samtools

jQuery make global variable

You can avoid declaration of global variables by adding them directly to the global object:

(function(global) {

  ...

  global.varName = someValue;

  ...

}(this));

A disadvantage of this method is that global.varName won't exist until that specific line of code is executed, but that can be easily worked around.

You might also consider an application architecture where such globals are held in a closure common to all functions that need them, or as properties of a suitably accessible data storage object.

offsetTop vs. jQuery.offset().top

It is possible that the offset could be a non-integer, using em as the measurement unit, relative font-sizes in %.

I also theorise that the offset might not be a whole number when the zoom isn't 100% but that depends how the browser handles scaling.

How can I pass a Bitmap object from one activity to another

In my case, the way mentioned above didn't worked for me. Every time I put the bitmap in the intent, the 2nd activity didn't start. The same happened when I passed the bitmap as byte[].

I followed this link and it worked like a charme and very fast:

package your.packagename

import android.graphics.Bitmap;

public class CommonResources { 
      public static Bitmap photoFinishBitmap = null;
}

in my 1st acitiviy:

Constants.photoFinishBitmap = photoFinishBitmap;
Intent intent = new Intent(mContext, ImageViewerActivity.class);
startActivity(intent);

and here is the onCreate() of my 2nd Activity:

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Bitmap photo = Constants.photoFinishBitmap;
    if (photo != null) {
        mViewHolder.imageViewerImage.setImageDrawable(new BitmapDrawable(getResources(), photo));
    }
}

SVN upgrade working copy

With AnkhSVN in Visual Studio, there's also an "Upgrade Working Copy" option under the context menu for the solution in the Solution Explorer (when applicable).

How to press/click the button using Selenium if the button does not have the Id?

    You can achieve this by using cssSelector 
    // Use of List web elements:
    String cssSelectorOfLoginButton="input[type='button'][id='login']"; 
    //****Add cssSelector of your 1st webelement
    //List<WebElement> button 
    =driver.findElements(By.cssSelector(cssSelectorOfLoginButton));
    button.get(0).click();

    I hope this work for you

Delete column from SQLite table

I've made a Python function where you enter the table and column to remove as arguments:

def removeColumn(table, column):
    columns = []
    for row in c.execute('PRAGMA table_info(' + table + ')'):
        columns.append(row[1])
    columns.remove(column)
    columns = str(columns)
    columns = columns.replace("[", "(")
    columns = columns.replace("]", ")")
    for i in ["\'", "(", ")"]:
        columns = columns.replace(i, "")
    c.execute('CREATE TABLE temptable AS SELECT ' + columns + ' FROM ' + table)
    c.execute('DROP TABLE ' + table)
    c.execute('ALTER TABLE temptable RENAME TO ' + table)
    conn.commit()

As per the info on Duda's and MeBigFatGuy's answers this won't work if there is a foreign key on the table, but this can be fixed with 2 lines of code (creating a new table and not just renaming the temporary table)

How to replace all spaces in a string

You can do the following fix for removing Whitespaces with trim and @ symbol:

var result = string.replace(/ /g, '');  // Remove whitespaces with trimmed value
var result = string.replace(/ /g, '@'); // Remove whitespaces with *@* symbol

xcode library not found

The problem might be the following: SVN ignores .a files because of its global config, which means someone didn't commit the libGoogleAnalytics.a to SVN, because it didn't show up in SVN. So now you try to check out the project from SVN which now misses the libGoogleAnalytics.a (since it was ignored and was not committed). Of course the build fails.

You might want to change the global ignore config from SVN to stop ignoring *.a files.

Or just add the one missing libGoogleAnalytics.a file manually to your SVN working copy instead of changing SVNs global ignore config.

Then re-add libGoogleAnalytics.a to your XCode project and commit it to SVN.

How to develop or migrate apps for iPhone 5 screen resolution?

If you have an app built for iPhone 4S or earlier, it'll run letterboxed on iPhone 5.

To adapt your app to the new taller screen, the first thing you do is to change the launch image to: [email protected]. Its size should be 1136x640 (HxW). Yep, having the default image in the new screen size is the key to let your app take the whole of new iPhone 5's screen.

(Note that the naming convention works only for the default image. Naming another image "[email protected]" will not cause it to be loaded in place of "[email protected]". If you need to load different images for different screen sizes, you'll have to do it programmatically.)

If you're very very lucky, that might be it... but in all likelihood, you'll have to take a few more steps.

  • Make sure, your Xibs/Views use auto-layout to resize themselves.
  • Use springs and struts to resize views.
  • If this is not good enough for your app, design your xib/storyboard for one specific screen size and reposition programmatically for the other.

In the extreme case (when none of the above suffices), design the two Xibs and load the appropriate one in the view controller.

To detect screen size:

if(UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone)
{
    CGSize result = [[UIScreen mainScreen] bounds].size;
    if(result.height == 480)
    {
        // iPhone Classic
    }
    if(result.height == 568)
    {
        // iPhone 5
    }
}

How can I check if a background image is loaded?

Here is a simple vanilla hack ~

(function(image){
  image.onload = function(){ 
                   $(body).addClass('loaded-background');
                   alert('Background image done loading');
                   // TODO fancy fade-in
                 };
  image.src    = "http://picture.de/image.png";
})(new Image());

How to format Joda-Time DateTime to only mm/dd/yyyy?

This works

String x = "22/06/2012";
String y = "25/10/2014";

String datestart = x;
String datestop = y;

//DateTimeFormatter format = DateTimeFormat.forPattern("dd/mm/yyyy");
SimpleDateFormat  format = new SimpleDateFormat("dd/mm/yyyy");

Date d1 = null;
Date d2 = null;

try {
    d1 =  format.parse(datestart);
    d2 = format.parse(datestop);

    DateTime dt1 = new DateTime(d1);
    DateTime dt2 = new DateTime(d2);

    //Period
    period = new Period (dt1,dt2);

    //calculate days
    int days = Days.daysBetween(dt1, dt2).getDays();


} catch (ParseException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

CSS technique for a horizontal line with words in the middle

Here is Flex based solution.

A heading with a central horizontal line to its sides

_x000D_
_x000D_
h1 {
  display: flex;
  flex-direction: row;
}
h1:before, h1:after{
  content: "";
  flex: 1 1;
  border-bottom: 1px solid;
  margin: auto;
}
h1:before {
  margin-right: 10px
}
h1:after {
  margin-left: 10px
}
_x000D_
<h1>Today</h1>
_x000D_
_x000D_
_x000D_

JSFiddle: https://jsfiddle.net/j0y7uaqL/

How to define two fields "unique" as couple

Django 2.2+

Using the constraints features UniqueConstraint is preferred over unique_together.

From the Django documentation for unique_together:

Use UniqueConstraint with the constraints option instead.
UniqueConstraint provides more functionality than unique_together.
unique_together may be deprecated in the future.

For example:

class Volume(models.Model):
    id = models.AutoField(primary_key=True)
    journal_id = models.ForeignKey(Journals, db_column='jid', null=True, verbose_name="Journal")
    volume_number = models.CharField('Volume Number', max_length=100)
    comments = models.TextField('Comments', max_length=4000, blank=True)

    class Meta:
        constraints = [
            models.UniqueConstraint(fields=['journal_id', 'volume_number'], name='name of constraint')
        ]

ImportError: No module named pythoncom

If you're on windows you probably want the pywin32 library, which includes pythoncom and a whole lot of other stuff that is pretty standard.

boolean in an if statement

If you write: if(x === true) , It will be true for only x = true

If you write: if(x) , it will be true for any x that is not: '' (empty string), false, null, undefined, 0, NaN.

java.net.ConnectException: Connection refused

I had same problem and the problem was that I was not closing socket object.After using socket.close(); problem solved. This code works for me.

ClientDemo.java

public class ClientDemo {
    public static void main(String[] args) throws UnknownHostException,
            IOException {
        Socket socket = new Socket("127.0.0.1", 55286);
        OutputStreamWriter os = new OutputStreamWriter(socket.getOutputStream());
        os.write("Santosh Karna");
        os.flush();
        socket.close();
    }
}

and ServerDemo.java

public class ServerDemo {
    public static void main(String[] args) throws IOException {
        System.out.println("server is started");
        ServerSocket serverSocket= new ServerSocket(55286);
        System.out.println("server is waiting");
        Socket socket=serverSocket.accept();
        System.out.println("Client connected");
        BufferedReader reader=new BufferedReader(new InputStreamReader(socket.getInputStream()));
        String str=reader.readLine();
        System.out.println("Client data: "+str);
        socket.close();
        serverSocket.close();

    }
}

How to display the value of the bar on each bar with pyplot.barh()?

Use plt.text() to put text in the plot.

Example:

import matplotlib.pyplot as plt
N = 5
menMeans = (20, 35, 30, 35, 27)
ind = np.arange(N)

#Creating a figure with some fig size
fig, ax = plt.subplots(figsize = (10,5))
ax.bar(ind,menMeans,width=0.4)
#Now the trick is here.
#plt.text() , you need to give (x,y) location , where you want to put the numbers,
#So here index will give you x pos and data+1 will provide a little gap in y axis.
for index,data in enumerate(menMeans):
    plt.text(x=index , y =data+1 , s=f"{data}" , fontdict=dict(fontsize=20))
plt.tight_layout()
plt.show()

This will show the figure as:

bar chart with values at the top

Serializing an object as UTF-8 XML in .NET

Very good answer using inheritance, just remember to override the initializer

public class Utf8StringWriter : StringWriter
{
    public Utf8StringWriter(StringBuilder sb) : base (sb)
    {
    }
    public override Encoding Encoding { get { return Encoding.UTF8; } }
}

Eclipse CDT project built but "Launch Failed. Binary Not Found"

After trying everything here what worked for me was to grant execution permission to eclipse:

cd eclipse-installation-dir 
sudo chmod +x eclipse

Using Eclipse Luna on Ubuntu 12.04 LTS.

Find all elements with a certain attribute value in jquery

$('div[imageId="imageN"]').each(function() {
    // `this` is the div
});

To check for the sole existence of the attribute, no matter which value, you could use ths selector instead: $('div[imageId]')

How do you receive a url parameter with a spring controller mapping

You have a lot of variants for using @RequestParam with additional optional elements, e.g.

@RequestParam(required = false, defaultValue = "someValue", value="someAttr") String someAttr

If you don't put required = false - param will be required by default.

defaultValue = "someValue" - the default value to use as a fallback when the request parameter is not provided or has an empty value.

If request and method param are the same - you don't need value = "someAttr"

How to access Spring MVC model object in javascript file?

   @RequestMapping("/op")
   public ModelAndView method(Map<String, Object> model) {
       model.put("att", "helloooo");
       return new ModelAndView("dom/op");
   }

In your .js

<script>
    var valVar = [[${att}]];
</script>

Improving bulk insert performance in Entity framework

There is opportunity for several improvements (if you are using DbContext):

Set:

yourContext.Configuration.AutoDetectChangesEnabled = false;
yourContext.Configuration.ValidateOnSaveEnabled = false;

Do SaveChanges() in packages of 100 inserts... or you can try with packages of 1000 items and see the changes in performance.

Since during all this inserts, the context is the same and it is getting bigger, you can rebuild your context object every 1000 inserts. var yourContext = new YourContext(); I think this is the big gain.

Doing this improvements in an importing data process of mine, took it from 7 minutes to 6 seconds.

The actual numbers... could not be 100 or 1000 in your case... try it and tweak it.

ReferenceError: event is not defined error in Firefox

It is because you forgot to pass in event into the click function:

$('.menuOption').on('click', function (e) { // <-- the "e" for event

    e.preventDefault(); // now it'll work

    var categories = $(this).attr('rel');
    $('.pages').hide();
    $(categories).fadeIn();
});

On a side note, e is more commonly used as opposed to the word event since Event is a global variable in most browsers.

Creating a daemon in Linux

In Linux i want to add a daemon that cannot be stopped and which monitors filesystem changes. If any changes would be detected it should write the path to the console where it was started + a newline.

Daemons work in the background and (usually...) don't belong to a TTY that's why you can't use stdout/stderr in the way you probably want. Usually a syslog daemon (syslogd) is used for logging messages to files (debug, error,...).

Besides that, there are a few required steps to daemonize a process.


If I remember correctly these steps are:

  • fork off the parent process & let it terminate if forking was successful. -> Because the parent process has terminated, the child process now runs in the background.
  • setsid - Create a new session. The calling process becomes the leader of the new session and the process group leader of the new process group. The process is now detached from its controlling terminal (CTTY).
  • Catch signals - Ignore and/or handle signals.
  • fork again & let the parent process terminate to ensure that you get rid of the session leading process. (Only session leaders may get a TTY again.)
  • chdir - Change the working directory of the daemon.
  • umask - Change the file mode mask according to the needs of the daemon.
  • close - Close all open file descriptors that may be inherited from the parent process.

To give you a starting point: Look at this skeleton code that shows the basic steps. This code can now also be forked on GitHub: Basic skeleton of a linux daemon

/*
 * daemonize.c
 * This example daemonizes a process, writes a few log messages,
 * sleeps 20 seconds and terminates afterwards.
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <syslog.h>

static void skeleton_daemon()
{
    pid_t pid;

    /* Fork off the parent process */
    pid = fork();

    /* An error occurred */
    if (pid < 0)
        exit(EXIT_FAILURE);

    /* Success: Let the parent terminate */
    if (pid > 0)
        exit(EXIT_SUCCESS);

    /* On success: The child process becomes session leader */
    if (setsid() < 0)
        exit(EXIT_FAILURE);

    /* Catch, ignore and handle signals */
    //TODO: Implement a working signal handler */
    signal(SIGCHLD, SIG_IGN);
    signal(SIGHUP, SIG_IGN);

    /* Fork off for the second time*/
    pid = fork();

    /* An error occurred */
    if (pid < 0)
        exit(EXIT_FAILURE);

    /* Success: Let the parent terminate */
    if (pid > 0)
        exit(EXIT_SUCCESS);

    /* Set new file permissions */
    umask(0);

    /* Change the working directory to the root directory */
    /* or another appropriated directory */
    chdir("/");

    /* Close all open file descriptors */
    int x;
    for (x = sysconf(_SC_OPEN_MAX); x>=0; x--)
    {
        close (x);
    }

    /* Open the log file */
    openlog ("firstdaemon", LOG_PID, LOG_DAEMON);
}
int main()
{
    skeleton_daemon();

    while (1)
    {
        //TODO: Insert daemon code here.
        syslog (LOG_NOTICE, "First daemon started.");
        sleep (20);
        break;
    }

    syslog (LOG_NOTICE, "First daemon terminated.");
    closelog();

    return EXIT_SUCCESS;
}


  • Compile the code: gcc -o firstdaemon daemonize.c
  • Start the daemon: ./firstdaemon
  • Check if everything is working properly: ps -xj | grep firstdaemon

  • The output should be similar to this one:

+------+------+------+------+-----+-------+------+------+------+-----+
| PPID | PID  | PGID | SID  | TTY | TPGID | STAT | UID  | TIME | CMD |
+------+------+------+------+-----+-------+------+------+------+-----+
|    1 | 3387 | 3386 | 3386 | ?   |    -1 | S    | 1000 | 0:00 | ./  |
+------+------+------+------+-----+-------+------+------+------+-----+

What you should see here is:

  • The daemon has no controlling terminal (TTY = ?)
  • The parent process ID (PPID) is 1 (The init process)
  • The PID != SID which means that our process is NOT the session leader
    (because of the second fork())
  • Because PID != SID our process can't take control of a TTY again

Reading the syslog:

  • Locate your syslog file. Mine is here: /var/log/syslog
  • Do a: grep firstdaemon /var/log/syslog

  • The output should be similar to this one:

  firstdaemon[3387]: First daemon started.
  firstdaemon[3387]: First daemon terminated.


A note: In reality you would also want to implement a signal handler and set up the logging properly (Files, log levels...).

Further reading:

How to calculate difference between two dates in oracle 11g SQL

You can use this:

SET FEEDBACK OFF;
SET SERVEROUTPUT ON;

DECLARE
  V_START_DATE  CHAR(17) := '28/03/16 17:20:00';
  V_END_DATE    CHAR(17) := '30/03/16 17:50:10';
  V_DATE_DIFF   VARCHAR2(17);

BEGIN

SELECT
  (TO_NUMBER( SUBSTR(NUMTODSINTERVAL(TO_DATE(V_END_DATE , 'DD/MM/YY HH24:MI:SS') - TO_DATE(V_START_DATE, 'DD/MM/YY HH24:MI:SS'), 'DAY'), 02, 9)) * 24) +
  (TO_NUMBER( SUBSTR(NUMTODSINTERVAL(TO_DATE(V_END_DATE , 'DD/MM/YY HH24:MI:SS') - TO_DATE(V_START_DATE, 'DD/MM/YY HH24:MI:SS'), 'DAY'), 12, 2)))  || 
              SUBSTR(NUMTODSINTERVAL(TO_DATE(V_END_DATE , 'DD/MM/YY HH24:MI:SS') - TO_DATE(V_START_DATE, 'DD/MM/YY HH24:MI:SS'), 'DAY'), 14, 6) AS "HH24:MI:SS"
  INTO V_DATE_DIFF
FROM 
  DUAL;

DBMS_OUTPUT.PUT_LINE(V_DATE_DIFF);
END;

Lightweight Javascript DB for use in Node.js

LevelUP aims to expose the features of LevelDB in a Node.js-friendly way.

https://github.com/rvagg/node-levelup

You can also look at UnQLite. with a node.js binding node-unqlite

https://github.com/symisc/unqlite

How do I undo 'git add' before commit?

The first time I had this problem, I found this post here and from the first answer I learned that I should just do git reset <filename>. It worked fine.

Eventually, I happened to have a few subfolders inside my main git folder. I found it easy to just do git add . to add all files inside the subfolders and then git reset the few files that I did not want to add.

Nowadays I have lots of files and subfolders. It is tedious to git reset one-by-one but still easier to just git add . first, then reset the few heavy/unwanted but useful files and folders.

I've found the following method (which is not recorded here or here) relatively easy. I hope it will be helpful:

Let's say that you have the following situation:

Folder/SubFolder1/file1.txt
Folder/SubFolder2/fig1.png
Folder/SubFolderX/fig.svg
Folder/SubFolder3/<manyfiles>
Folder/SubFolder4/<file1.py, file2.py, ..., file60.py, ...>

You want to add all folders and files but not fig1.png, and not SubFolderX, and not file60.py and the list keeps growing ...

First, make/create a bash shell script and give it a name. Say, git_add.sh:

Then add all the paths to all folders and files you want to git reset preceded by git reset -- . You can easily copy-paste the paths into the script git_add.sh as your list of files grows. The git_add.sh script should look like this:

#!/bin/bash

git add .
git reset -- Folder/SubFolder2/fig1.png
git reset -- Folder/SubFolderX
git reset -- Folder/SubFolder4/file60.py

#!/bin/bash is important. After this, you need to do chmod -x git_add.sh in the command line to make the script executable and then source git_add.sh to run it. After that, you can do git commit -m "some comment", and then git push -u origin master if you have already set up Bitbucket/Github.

Disclaimer: I've only tested this in Linux.

Eclipse not recognizing JVM 1.8

For some weird reason "Java SE Development Kit 8u151" gives this trouble. Just install, "Java SE Development Kit 8u152" from the following link-

http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

It should work then.

Executing <script> elements inserted with .innerHTML

Extending off of Larry's. I made it recursively search the entire block and children nodes.
The script now will also call external scripts that are specified with src parameter. Scripts are appended to the head instead of inserted and placed in the order they are found. So specifically order scripts are preserved. And each script is executed synchronously similar to how the browser handles the initial DOM loading. So if you have a script block that calls jQuery from a CDN and than the next script node uses jQuery... No prob! Oh and I tagged the appended scripts with a serialized id based off of what you set in the tag parameter so you can find what was added by this script.

exec_body_scripts: function(body_el, tag) {
    // Finds and executes scripts in a newly added element's body.
    // Needed since innerHTML does not run scripts.
    //
    // Argument body_el is an element in the dom.

    function nodeName(elem, name) {
        return elem.nodeName && elem.nodeName.toUpperCase() ===
              name.toUpperCase();
    };

    function evalScript(elem, id, callback) {
        var data = (elem.text || elem.textContent || elem.innerHTML || "" ),
            head = document.getElementsByTagName("head")[0] ||
                      document.documentElement;

        var script = document.createElement("script");
        script.type = "text/javascript";
        if (id != '') {
            script.setAttribute('id', id);
        }

        if (elem.src != '') {
            script.src = elem.src;
            head.appendChild(script);
            // Then bind the event to the callback function.
            // There are several events for cross browser compatibility.
            script.onreadystatechange = callback;
            script.onload = callback;
        } else {
            try {
                // doesn't work on ie...
                script.appendChild(document.createTextNode(data));      
            } catch(e) {
                // IE has funky script nodes
                script.text = data;
            }
            head.appendChild(script);
            callback();
        }
    };

    function walk_children(node) {
        var scripts = [],
          script,
          children_nodes = node.childNodes,
          child,
          i;

        if (children_nodes === undefined) return;

        for (i = 0; i<children_nodes.length; i++) {
            child = children_nodes[i];
            if (nodeName(child, "script" ) &&
                (!child.type || child.type.toLowerCase() === "text/javascript")) {
                scripts.push(child);
            } else {
                var new_scripts = walk_children(child);
                for(j=0; j<new_scripts.length; j++) {
                    scripts.push(new_scripts[j]);
                }
            }
        }

        return scripts;
    }

    var i = 0;
    function execute_script(i) {
        script = scripts[i];
        if (script.parentNode) {script.parentNode.removeChild(script);}
        evalScript(scripts[i], tag+"_"+i, function() {
            if (i < scripts.length-1) {
                execute_script(++i);
            }                
        });
    }

    // main section of function
    if (tag === undefined) tag = 'tmp';

    var scripts = walk_children(body_el);

    execute_script(i);
}

How do you fix the "element not interactable" exception?

It's worth noting that there is a sleep function built into Selenium.

driver.implicitly_wait(5)

When to use a View instead of a Table?

According to Wikipedia,

Views can provide many advantages over tables:

  • Views can represent a subset of the data contained in a table.
  • Views can limit the degree of exposure of the underlying tables to the outer world: a given user may have permission to query the view, while denied access to the rest of the base table.

  • Views can join and simplify multiple tables into a single virtual table.

  • Views can act as aggregated tables, where the database engine aggregates data (sum, average, etc.) and presents the calculated results as part of the data.

  • Views can hide the complexity of data. For example, a view could appear as Sales2000 or Sales2001, transparently partitioning the actual underlying table.

  • Views take very little space to store; the database contains only the definition of a view, not a copy of all the data that it presents.

  • Views can provide extra security, depending on the SQL engine used.

INSERT INTO...SELECT for all MySQL columns

More Examples & Detail

    INSERT INTO vendors (
     name, 
     phone, 
     addressLine1,
     addressLine2,
     city,
     state,
     postalCode,
     country,
     customer_id
 )
 SELECT 
     name,
     phone,
     addressLine1,
     addressLine2,
     city,
     state ,
     postalCode,
     country,
     customer_id
 FROM 
     customers;

SQL Inner join 2 tables with multiple column conditions and update

You need to do

Update table_xpto
set column_xpto = x.xpto_New
    ,column2 = x.column2New
from table_xpto xpto
   inner join table_xptoNew xptoNew ON xpto.bla = xptoNew.Bla
where <clause where>

If you need a better answer, you can give us more information :)

Add a dependency in Maven

I'd do this:

  1. add the dependency as you like in your pom:

    <dependency>
            <groupId>com.stackoverflow...</groupId>
            <artifactId>artifactId...</artifactId>
            <version>1.0</version>
    </dependency>
    

  2. run mvn install it will try to download the jar and fail. On the process, it will give you the complete command of installing the jar with the error message. Copy that command and run it! easy huh?!

Get Android API level of phone currently running my application

try this :Float.valueOf(android.os.Build.VERSION.RELEASE) <= 2.1

Get a DataTable Columns DataType

dt.Columns[0].DataType.Name.ToString()

How to check that an element is in a std::set?

I was able to write a general contains function for std::list and std::vector,

template<typename T>
bool contains( const list<T>& container, const T& elt )
{
  return find( container.begin(), container.end(), elt ) != container.end() ;
}

template<typename T>
bool contains( const vector<T>& container, const T& elt )
{
  return find( container.begin(), container.end(), elt ) != container.end() ;
}

// use:
if( contains( yourList, itemInList ) ) // then do something

This cleans up the syntax a bit.

But I could not use template template parameter magic to make this work arbitrary stl containers.

// NOT WORKING:
template<template<class> class STLContainer, class T>
bool contains( STLContainer<T> container, T elt )
{
  return find( container.begin(), container.end(), elt ) != container.end() ;
}

Any comments about improving the last answer would be nice.

How to extract img src, title and alt from html using php?

EDIT : now that I know better

Using regexp to solve this kind of problem is a bad idea and will likely lead in unmaintainable and unreliable code. Better use an HTML parser.

Solution With regexp

In that case it's better to split the process into two parts :

  • get all the img tag
  • extract their metadata

I will assume your doc is not xHTML strict so you can't use an XML parser. E.G. with this web page source code :

/* preg_match_all match the regexp in all the $html string and output everything as 
an array in $result. "i" option is used to make it case insensitive */

preg_match_all('/<img[^>]+>/i',$html, $result); 

print_r($result);
Array
(
    [0] => Array
        (
            [0] => <img src="/Content/Img/stackoverflow-logo-250.png" width="250" height="70" alt="logo link to homepage" />
            [1] => <img class="vote-up" src="/content/img/vote-arrow-up.png" alt="vote up" title="This was helpful (click again to undo)" />
            [2] => <img class="vote-down" src="/content/img/vote-arrow-down.png" alt="vote down" title="This was not helpful (click again to undo)" />
            [3] => <img src="http://www.gravatar.com/avatar/df299babc56f0a79678e567e87a09c31?s=32&d=identicon&r=PG" height=32 width=32 alt="gravatar image" />
            [4] => <img class="vote-up" src="/content/img/vote-arrow-up.png" alt="vote up" title="This was helpful (click again to undo)" />

[...]
        )

)

Then we get all the img tag attributes with a loop :

$img = array();
foreach( $result as $img_tag)
{
    preg_match_all('/(alt|title|src)=("[^"]*")/i',$img_tag, $img[$img_tag]);
}

print_r($img);

Array
(
    [<img src="/Content/Img/stackoverflow-logo-250.png" width="250" height="70" alt="logo link to homepage" />] => Array
        (
            [0] => Array
                (
                    [0] => src="/Content/Img/stackoverflow-logo-250.png"
                    [1] => alt="logo link to homepage"
                )

            [1] => Array
                (
                    [0] => src
                    [1] => alt
                )

            [2] => Array
                (
                    [0] => "/Content/Img/stackoverflow-logo-250.png"
                    [1] => "logo link to homepage"
                )

        )

    [<img class="vote-up" src="/content/img/vote-arrow-up.png" alt="vote up" title="This was helpful (click again to undo)" />] => Array
        (
            [0] => Array
                (
                    [0] => src="/content/img/vote-arrow-up.png"
                    [1] => alt="vote up"
                    [2] => title="This was helpful (click again to undo)"
                )

            [1] => Array
                (
                    [0] => src
                    [1] => alt
                    [2] => title
                )

            [2] => Array
                (
                    [0] => "/content/img/vote-arrow-up.png"
                    [1] => "vote up"
                    [2] => "This was helpful (click again to undo)"
                )

        )

    [<img class="vote-down" src="/content/img/vote-arrow-down.png" alt="vote down" title="This was not helpful (click again to undo)" />] => Array
        (
            [0] => Array
                (
                    [0] => src="/content/img/vote-arrow-down.png"
                    [1] => alt="vote down"
                    [2] => title="This was not helpful (click again to undo)"
                )

            [1] => Array
                (
                    [0] => src
                    [1] => alt
                    [2] => title
                )

            [2] => Array
                (
                    [0] => "/content/img/vote-arrow-down.png"
                    [1] => "vote down"
                    [2] => "This was not helpful (click again to undo)"
                )

        )

    [<img src="http://www.gravatar.com/avatar/df299babc56f0a79678e567e87a09c31?s=32&d=identicon&r=PG" height=32 width=32 alt="gravatar image" />] => Array
        (
            [0] => Array
                (
                    [0] => src="http://www.gravatar.com/avatar/df299babc56f0a79678e567e87a09c31?s=32&d=identicon&r=PG"
                    [1] => alt="gravatar image"
                )

            [1] => Array
                (
                    [0] => src
                    [1] => alt
                )

            [2] => Array
                (
                    [0] => "http://www.gravatar.com/avatar/df299babc56f0a79678e567e87a09c31?s=32&d=identicon&r=PG"
                    [1] => "gravatar image"
                )

        )

   [..]
        )

)

Regexps are CPU intensive so you may want to cache this page. If you have no cache system, you can tweak your own by using ob_start and loading / saving from a text file.

How does this stuff work ?

First, we use preg_ match_ all, a function that gets every string matching the pattern and ouput it in it's third parameter.

The regexps :

<img[^>]+>

We apply it on all html web pages. It can be read as every string that starts with "<img", contains non ">" char and ends with a >.

(alt|title|src)=("[^"]*")

We apply it successively on each img tag. It can be read as every string starting with "alt", "title" or "src", then a "=", then a ' " ', a bunch of stuff that are not ' " ' and ends with a ' " '. Isolate the sub-strings between ().

Finally, every time you want to deal with regexps, it handy to have good tools to quickly test them. Check this online regexp tester.

EDIT : answer to the first comment.

It's true that I did not think about the (hopefully few) people using single quotes.

Well, if you use only ', just replace all the " by '.

If you mix both. First you should slap yourself :-), then try to use ("|') instead or " and [^ø] to replace [^"].

I get conflicting provisioning settings error when I try to archive to submit an iOS app

I had this same issue. I realized that it was because I was using xcode while I was using it. Since the updates didn't install correctly, it caused these errors to show up. The only thing that fixed it was to quit xcode and reopen it. When I reopened it, it prompted me to install updates. After the updates were installed, the errors went away.

Checking Bash exit status of several commands efficiently

You can use @john-kugelman 's awesome solution found above on non-RedHat systems by commenting out this line in his code:

. /etc/init.d/functions

Then, paste the below code at the end. Full disclosure: This is just a direct copy & paste of the relevant bits of the above mentioned file taken from Centos 7.

Tested on MacOS and Ubuntu 18.04.


BOOTUP=color
RES_COL=60
MOVE_TO_COL="echo -en \\033[${RES_COL}G"
SETCOLOR_SUCCESS="echo -en \\033[1;32m"
SETCOLOR_FAILURE="echo -en \\033[1;31m"
SETCOLOR_WARNING="echo -en \\033[1;33m"
SETCOLOR_NORMAL="echo -en \\033[0;39m"

echo_success() {
    [ "$BOOTUP" = "color" ] && $MOVE_TO_COL
    echo -n "["
    [ "$BOOTUP" = "color" ] && $SETCOLOR_SUCCESS
    echo -n $"  OK  "
    [ "$BOOTUP" = "color" ] && $SETCOLOR_NORMAL
    echo -n "]"
    echo -ne "\r"
    return 0
}

echo_failure() {
    [ "$BOOTUP" = "color" ] && $MOVE_TO_COL
    echo -n "["
    [ "$BOOTUP" = "color" ] && $SETCOLOR_FAILURE
    echo -n $"FAILED"
    [ "$BOOTUP" = "color" ] && $SETCOLOR_NORMAL
    echo -n "]"
    echo -ne "\r"
    return 1
}

echo_passed() {
    [ "$BOOTUP" = "color" ] && $MOVE_TO_COL
    echo -n "["
    [ "$BOOTUP" = "color" ] && $SETCOLOR_WARNING
    echo -n $"PASSED"
    [ "$BOOTUP" = "color" ] && $SETCOLOR_NORMAL
    echo -n "]"
    echo -ne "\r"
    return 1
}

echo_warning() {
    [ "$BOOTUP" = "color" ] && $MOVE_TO_COL
    echo -n "["
    [ "$BOOTUP" = "color" ] && $SETCOLOR_WARNING
    echo -n $"WARNING"
    [ "$BOOTUP" = "color" ] && $SETCOLOR_NORMAL
    echo -n "]"
    echo -ne "\r"
    return 1
} 

Delete with Join in MySQL

Single Table Delete:

In order to delete entries from posts table:

DELETE ps 
FROM clients C 
INNER JOIN projects pj ON C.client_id = pj.client_id
INNER JOIN posts ps ON pj.project_id = ps.project_id
WHERE C.client_id = :client_id;

In order to delete entries from projects table:

DELETE pj 
FROM clients C 
INNER JOIN projects pj ON C.client_id = pj.client_id
INNER JOIN posts ps ON pj.project_id = ps.project_id
WHERE C.client_id = :client_id;

In order to delete entries from clients table:

DELETE C
FROM clients C 
INNER JOIN projects pj ON C.client_id = pj.client_id
INNER JOIN posts ps ON pj.project_id = ps.project_id
WHERE C.client_id = :client_id;

Multiple Tables Delete:

In order to delete entries from multiple tables out of the joined results you need to specify the table names after DELETE as comma separated list:

Suppose you want to delete entries from all the three tables (posts,projects,clients) for a particular client :

DELETE C,pj,ps 
FROM clients C 
INNER JOIN projects pj ON C.client_id = pj.client_id
INNER JOIN posts ps ON pj.project_id = ps.project_id
WHERE C.client_id = :client_id

Loop through JSON object List

had same problem today, Your topic helped me so here goes solution ;)

 alert(result.d[0].EmployeeTitle);

How to get the sign, mantissa and exponent of a floating point number

On Linux package glibc-headers provides header #include <ieee754.h> with floating point types definitions, e.g.:

union ieee754_double
  {
    double d;

    /* This is the IEEE 754 double-precision format.  */
    struct
      {
#if __BYTE_ORDER == __BIG_ENDIAN
    unsigned int negative:1;
    unsigned int exponent:11;
    /* Together these comprise the mantissa.  */
    unsigned int mantissa0:20;
    unsigned int mantissa1:32;
#endif              /* Big endian.  */
#if __BYTE_ORDER == __LITTLE_ENDIAN
# if    __FLOAT_WORD_ORDER == __BIG_ENDIAN
    unsigned int mantissa0:20;
    unsigned int exponent:11;
    unsigned int negative:1;
    unsigned int mantissa1:32;
# else
    /* Together these comprise the mantissa.  */
    unsigned int mantissa1:32;
    unsigned int mantissa0:20;
    unsigned int exponent:11;
    unsigned int negative:1;
# endif
#endif              /* Little endian.  */
      } ieee;

    /* This format makes it easier to see if a NaN is a signalling NaN.  */
    struct
      {
#if __BYTE_ORDER == __BIG_ENDIAN
    unsigned int negative:1;
    unsigned int exponent:11;
    unsigned int quiet_nan:1;
    /* Together these comprise the mantissa.  */
    unsigned int mantissa0:19;
    unsigned int mantissa1:32;
#else
# if    __FLOAT_WORD_ORDER == __BIG_ENDIAN
    unsigned int mantissa0:19;
    unsigned int quiet_nan:1;
    unsigned int exponent:11;
    unsigned int negative:1;
    unsigned int mantissa1:32;
# else
    /* Together these comprise the mantissa.  */
    unsigned int mantissa1:32;
    unsigned int mantissa0:19;
    unsigned int quiet_nan:1;
    unsigned int exponent:11;
    unsigned int negative:1;
# endif
#endif
      } ieee_nan;
  };

#define IEEE754_DOUBLE_BIAS 0x3ff /* Added to exponent.  */

"This SqlTransaction has completed; it is no longer usable."... configuration error?

For what it's worth, I've run into this on what was previously working code. I had added SELECT statements in a trigger for debug testing and forgot to remove them. Entity Framework / MVC doesnt play nice when other stuff is output to the "grid". Make sure to check for any rogue queries and remove them.

What is the best way to iterate over multiple lists at once?

The usual way is to use zip():

for x, y in zip(a, b):
    # x is from a, y is from b

This will stop when the shorter of the two iterables a and b is exhausted. Also worth noting: itertools.izip() (Python 2 only) and itertools.izip_longest() (itertools.zip_longest() in Python 3).

How to find server name of SQL Server Management Studio

Make sure you have installed SQL Server.

If not, follow this link and download. https://www.microsoft.com/en-us/sql-server/sql-server-downloads

Once SQL server is installed successfully. You will get server name. Refer to the below picture:

enter image description here

Node.js console.log() not logging anything

Using modern --inspect with node the console.log is captured and relayed to the browser.

node --inspect myApp.js

or to capture early logging --inspect-brk can be used to stop the program on the first line of the first module...

node --inspect-brk myApp.js

Big O, how do you calculate/approximate it?

For the 1st case, the inner loop is executed n-i times, so the total number of executions is the sum for i going from 0 to n-1 (because lower than, not lower than or equal) of the n-i. You get finally n*(n + 1) / 2, so O(n²/2) = O(n²).

For the 2nd loop, i is between 0 and n included for the outer loop; then the inner loop is executed when j is strictly greater than n, which is then impossible.

Single vs double quotes in JSON

Two issues with answers given so far, if , for instance, one streams such non-standard JSON. Because then one might have to interpret an incoming string (not a python dictionary).

Issue 1 - demjson: With Python 3.7.+ and using conda I wasn't able to install demjson since obviosly it does not support Python >3.5 currently. So I need a solution with simpler means, for instance astand/or json.dumps.

Issue 2 - ast & json.dumps: If a JSON is both single quoted and contains a string in at least one value, which in turn contains single quotes, the only simple yet practical solution I have found is applying both:

In the following example we assume line is the incoming JSON string object :

>>> line = str({'abc':'008565','name':'xyz','description':'can control TV\'s and more'})

Step 1: convert the incoming string into a dictionary using ast.literal_eval()
Step 2: apply json.dumps to it for the reliable conversion of keys and values, but without touching the contents of values:

>>> import ast
>>> import json
>>> print(json.dumps(ast.literal_eval(line)))
{"abc": "008565", "name": "xyz", "description": "can control TV's and more"}

json.dumps alone would not do the job because it does not interpret the JSON, but only see the string. Similar for ast.literal_eval(): although it interprets correctly the JSON (dictionary), it does not convert what we need.

SQL: How to to SUM two values from different tables

select region,sum(number) total
from
(
    select region,number
    from cash_table
    union all
    select region,number
    from cheque_table
) t
group by region

Ignore outliers in ggplot2 boxplot

One idea would be to winsorize the data in a two-pass procedure:

  1. run a first pass, learn what the bounds are, e.g. cut of at given percentile, or N standard deviation above the mean, or ...

  2. in a second pass, set the values beyond the given bound to the value of that bound

I should stress that this is an old-fashioned method which ought to be dominated by more modern robust techniques but you still come across it a lot.

Measuring code execution time

Stopwatch measures time elapsed.

// Create new stopwatch
Stopwatch stopwatch = new Stopwatch();

// Begin timing
stopwatch.Start();

Threading.Thread.Sleep(500)

// Stop timing
stopwatch.Stop();

Console.WriteLine("Time elapsed: {0}", stopwatch.Elapsed);

Here is a DEMO.

Chrome extension id - how to find it

Extension IDs can be found in:

chrome://extensions (Chrome_Hotdog >> More_tools >> Extensions) Developer mode.

For Linux: $HOME/.config/google-chrome/Default/Preferences (json file) under ["extensions"].

Class JavaLaunchHelper is implemented in two places

This was an issue for me years ago and I'd previously fixed it in Eclipse by excluding 1.7 from my projects, but it became an issue again for IntelliJ, which I recently installed. I fixed it by:

  1. Uninstalling the JDK:

    cd /Library/Java/JavaVirtualMachines
    sudo rm -rf jdk1.8.0_45.jdk
    

    (I had jdk1.8.0_45.jdk installed; obviously you should uninstall whichever java version is listed in that folder. The offending files are located in that folder and should be deleted.)

  2. Downloading and installing JDK 9.

Note that the next time you create a new project, or open an existing project, you will need to set the project SDK to point to the new JDK install. You also may still see this bug or have it creep back if you have JDK 1.7 installed in your JavaVirtualMachines folder (which is what I believe happened to me).

How to use linux command line ftp with a @ sign in my username?

I've never seen the -u parameter. But if you want to use an "@", how about stating it as "\@"?

That way it should be interpreted as you intend. You know something like

ftp -u user\@[email protected]

Making view resize to its parent when added with addSubview

Just copy the parent view's frame to the child-view then add it. After that autoresizing will work. Actually you should only copy the size CGRectMake(0, 0, parentView.frame.size.width, parentView.frame.size.height)

childView.frame = CGRectMake(0, 0, parentView.frame.size.width, parentView.frame.size.height);
[parentView addSubview:childView];

Duplicating a MySQL table, indices, and data

To copy with indexes and triggers do these 2 queries:

CREATE TABLE newtable LIKE oldtable; 
INSERT INTO newtable SELECT * FROM oldtable;

To copy just structure and data use this one:

CREATE TABLE tbl_new AS SELECT * FROM tbl_old;

I've asked this before:

Copy a MySQL table including indexes

powerpoint loop a series of animation

Unfortunately you're probably done with the animation and presentation already. In the hopes this answer can help future questioners, however, this blog post has a walkthrough of steps that can loop a single slide as a sort of sub-presentation.

First, click Slide Show > Set Up Show.

Put a checkmark to Loop continuously until 'Esc'.

Click Ok. Now, Click Slide Show > Custom Shows. Click New.

Select the slide you are looping, click Add. Click Ok and Close.

Click on the slide you are looping. Click Slide Show > Slide Transition. Under Advance slide, put a checkmark to Automatically After. This will allow the slide to loop automatically. Do NOT Apply to all slides.

Right click on the thumbnail of the current slide, select Hide Slide.

Now, you will need to insert a new slide just before the slide you are looping. On the new slide, insert an action button. Set the hyperlink to the custom show you have created. Put a checkmark on "Show and Return"

This has worked for me.

How to disable phone number linking in Mobile Safari?

Why would you want to remove the linking, it makes it very user friendly to have th eoption.

If you simply want to remove the auto editing, but keep the link working just add this into your CSS...

a[href^=tel] {
 color: inherit;
 text-decoration:inherit;
}

Popup window in winform c#

Just create another form (let's call it formPopup) using Visual Studio. In a button handler write the following code:

var formPopup = new Form();
formPopup.Show(this); // if you need non-modal window

If you need a non-modal window use: formPopup.Show();. If you need a dialog (so your code will hang on this invocation until you close the opened form) use: formPopup.ShowDialog()

What is the current directory in a batch file?

It is the directory from where you start the batch file. E.g. if your batch is in c:\dir1\dir2 and you do cd c:\dir3, then run the batch, the current directory will be c:\dir3.

Generate preview image from Video file?

I recommend php-ffmpeg library.

Extracting image

You can extract a frame at any timecode using the FFMpeg\Media\Video::frame method.

This code returns a FFMpeg\Media\Frame instance corresponding to the second 42. You can pass any FFMpeg\Coordinate\TimeCode as argument, see dedicated documentation below for more information.

$frame = $video->frame(FFMpeg\Coordinate\TimeCode::fromSeconds(42));
$frame->save('image.jpg');

If you want to extract multiple images from the video, you can use the following filter:

$video
    ->filters()
    ->extractMultipleFrames(FFMpeg\Filters\Video\ExtractMultipleFramesFilter::FRAMERATE_EVERY_10SEC, '/path/to/destination/folder/')
    ->synchronize();

$video
    ->save(new FFMpeg\Format\Video\X264(), '/path/to/new/file');

By default, this will save the frames as jpg images.

You are able to override this using setFrameFileType to save the frames in another format:

$frameFileType = 'jpg'; // either 'jpg', 'jpeg' or 'png'
$filter = new ExtractMultipleFramesFilter($frameRate, $destinationFolder);
$filter->setFrameFileType($frameFileType);

$video->addFilter($filter);

The best way to calculate the height in a binary search tree? (balancing an AVL-tree)

Here's where it gets confusing, the text states "If the balance factor of R is 1, it means the insertion occurred on the (external) right side of that node and a left rotation is needed". But from m understanding the text said (as I quoted) that if the balance factor was within [-1, 1] then there was no need for balancing?

R is the right-hand child of the current node N.

If balance(N) = +2, then you need a rotation of some sort. But which rotation to use? Well, it depends on balance(R): if balance(R) = +1 then you need a left-rotation on N; but if balance(R) = -1 then you will need a double-rotation of some sort.

Selenium -- How to wait until page is completely loaded

3 answers, which you can combine:

  1. Set implicit wait immediately after creating the web driver instance:

    _ = driver.Manage().Timeouts().ImplicitWait;

    This will try to wait until the page is fully loaded on every page navigation or page reload.

  2. After page navigation, call JavaScript return document.readyState until "complete" is returned. The web driver instance can serve as JavaScript executor. Sample code:

    C#

    new WebDriverWait(driver, MyDefaultTimeout).Until(
    d => ((IJavaScriptExecutor) d).ExecuteScript("return document.readyState").Equals("complete"));
    

    Java

    new WebDriverWait(firefoxDriver, pageLoadTimeout).until(
          webDriver -> ((JavascriptExecutor) webDriver).executeScript("return document.readyState").equals("complete"));
    
  3. Check if the URL matches the pattern you expect.

Best way to move files between S3 buckets?

Actually as of recently I just use the copy+paste action in the AWS s3 interface. Just navigate to the files you want to copy, click on "Actions" -> "Copy" then navigate to the destination bucket and "Actions" -> "Paste"

It transfers the files pretty quick and it seems like a less convoluted solution that doesn't require any programming, or over the top solutions like that.