SyntaxFix

Programs & Examples On #Google talk

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Android: How to change CheckBox size?

Here was what I did, first set:

android:button="@null"

and also set 

android:drawableLeft="@drawable/selector_you_defined_for_your_checkbox"

then in your Java code:

Drawable d = mCheckBox.getCompoundDrawables()[0];
d.setBounds(0, 0, width_you_prefer, height_you_prefer);
mCheckBox.setCompoundDrawables(d, null, null, null);

It works for me, and hopefully it will work for you!

How to view file history in Git?

git log --all -- path/to/file should work

Printing out a number in assembly language?

Assembly language has no direct means of printing anything. Your assembler may or may not come with a library that supplies such a facility, otherwise you have to write it yourself, and it will be quite a complex function. You also have to decide where to print things - in a window, on the printer? In assembler, none of this is done for you.

What is a .NET developer?

I'd say the minimum would be to

  • know one of the .Net Languages (C#, VB.NET, etc.)
  • know the basic working of the .Net runtime
  • know and understand the core parts of the .Net class libraries
  • have an understanding about what additional classes and functions are available as part of the .Net class libraries

How to vertically align text in input type="text"?

The <textarea> element automatically aligns text at the top of a textbox, if you don't want to use CSS to force it.

How to store arbitrary data for some HTML tags

You could use hidden input tags. I get no validation errors at w3.org with this:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html lang='en' xml:lang='en' xmlns='http://www.w3.org/1999/xhtml'>
  <head>
    <meta content="text/html;charset=UTF-8" http-equiv="content-type" />
    <title>Hello</title>
  </head>
  <body>
    <div>
      <a class="article" href="link/for/non-js-users.html">
        <input style="display: none" name="articleid" type="hidden" value="5" />
      </a>
    </div>
  </body>
</html>

With jQuery you'd get the article ID with something like (not tested):

$('.article input[name=articleid]').val();

But I'd recommend HTML5 if that is an option.

Execute SQLite script

In order to execute simple queries and return to my shell script, I think this works well:

$ sqlite3 example.db 'SELECT * FROM some_table;'

How to maintain aspect ratio using HTML IMG tag

None of the methods listed scale the image to the largest possible size that fits in a box while retaining the desired aspect ratio.

This cannot be done with the IMG tag (at least not without a bit of JavaScript), but it can be done as follows:

 <div style="background:center no-repeat url(...);background-size:contain;width:...;height:..."></div>

Why do we have to normalize the input for an artificial neural network?

Looking at the neural network from the outside, it is just a function that takes some arguments and produces a result. As with all functions, it has a domain (i.e. a set of legal arguments). You have to normalize the values that you want to pass to the neural net in order to make sure it is in the domain. As with all functions, if the arguments are not in the domain, the result is not guaranteed to be appropriate.

The exact behavior of the neural net on arguments outside of the domain depends on the implementation of the neural net. But overall, the result is useless if the arguments are not within the domain.

Add values to app.config and retrieve them

sorry for late answer but may be my code may help u.

I placed 3 buttons on the winform surface. button1 & 2 will set different value and button3 will retrieve current value. so when run my code first add the reference System.configuration

and click on first button and then click on 3rd button to see what value has been set. next time again click on second & 3rd button to see again what value has been set after change.

so here is the code.

using System.Configuration;

 private void button1_Click(object sender, EventArgs e)
{
    Configuration config = ConfigurationManager.OpenExeConfiguration(Application.ExecutablePath);
    config.AppSettings.Settings.Remove("DBServerName");
    config.AppSettings.Settings.Add("DBServerName", "FirstAddedValue1");
    config.Save(ConfigurationSaveMode.Modified);
}

private void button2_Click(object sender, EventArgs e)
{
    Configuration config = ConfigurationManager.OpenExeConfiguration(Application.ExecutablePath);
    config.AppSettings.Settings.Remove("DBServerName");
    config.AppSettings.Settings.Add("DBServerName", "SecondAddedValue1");
    config.Save(ConfigurationSaveMode.Modified);
}

private void button3_Click(object sender, EventArgs e)
{
    Configuration config = ConfigurationManager.OpenExeConfiguration(Application.ExecutablePath);
          MessageBox.Show(config.AppSettings.Settings["DBServerName"].Value);
}

C compiling - "undefined reference to"?

As stated by a few others, this is a linking error. The section of code where this function is being called doesn't know what this function is. It either needs to be declared in a header file an defined in its own source file, or defined or declared in the same source file, above where it's being called.

Edit: In older versions of C, C89/C90, function declarations weren't actually required. So, you could just add the definition anywhere in the file in which you're using the function, even after the call and the compiler would infer the declaration. For example,

int main()
{
  int a = func();
}

int func()
{
   return 1;
}

However, this isn't good practice today and most languages, C++ for example, won't allow it. One way to get away with defining the function in the same source file in which you're using it, is to declare it at the beginning of the file. So, the previous example would look like this instead.

int func();

int main()
{
   int a = func();
}

int func()
{
  return 1;
}

Connecting to Microsoft SQL server using Python

An alternative approach would be installing Microsoft ODBC Driver 13, then replace SQLOLEDB with ODBC Driver 13 for SQL Server

Regards.

Only local connections are allowed Chrome and Selenium webdriver

Sorry for late post but still for info,I also facing same problem so I Used updated version of chromedriver ie.2.28 for updated chrome browser ie. 55 to 57 which resolved my problem.

Access multiple elements of list knowing their index

Kind of pythonic way:

c = [x for x in a if a.index(x) in b]

How to install a previous exact version of a NPM package?

On Ubuntu you can try this command.

sudo npm cache clean -f
sudo npm install -g n
sudo n stable

Specific version : sudo n 8.11.3 instead of sudo n stable

INSERT INTO a temp table, and have an IDENTITY field created, without first declaring the temp table?

If you want to include the column that is the current identity, you can still do that but you have to explicitly list the columns and cast the current identity to an int (assuming it is one now), like so:

select cast (CurrentID as int) as CurrentID, SomeOtherField, identity(int) as TempID 
into #temp
from myserver.dbo.mytable

Eclipse gives “Java was started but returned exit code 13”

I had the same problem. i was using windows8 with 64 bit OS. I just changed the path to Program Files(*86) and then it started work. I put this line in eclipse.ini file like,

-vm
 C:\Program Files (x86)\Java\jre7\bin\javaw.exe

Difference Between Schema / Database in MySQL

As defined in the MySQL Glossary:

In MySQL, physically, a schema is synonymous with a database. You can substitute the keyword SCHEMA instead of DATABASE in MySQL SQL syntax, for example using CREATE SCHEMA instead of CREATE DATABASE.

Some other database products draw a distinction. For example, in the Oracle Database product, a schema represents only a part of a database: the tables and other objects owned by a single user.

Making heatmap from pandas DataFrame

Please note that the authors of seaborn only want seaborn.heatmap to work with categorical dataframes. It's not general.

If your index and columns are numeric and/or datetime values, this code will serve you well.

Matplotlib heat-mapping function pcolormesh requires bins instead of indices, so there is some fancy code to build bins from your dataframe indices (even if your index isn't evenly spaced!).

The rest is simply np.meshgrid and plt.pcolormesh.

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt

def conv_index_to_bins(index):
    """Calculate bins to contain the index values.
    The start and end bin boundaries are linearly extrapolated from 
    the two first and last values. The middle bin boundaries are 
    midpoints.

    Example 1: [0, 1] -> [-0.5, 0.5, 1.5]
    Example 2: [0, 1, 4] -> [-0.5, 0.5, 2.5, 5.5]
    Example 3: [4, 1, 0] -> [5.5, 2.5, 0.5, -0.5]"""
    assert index.is_monotonic_increasing or index.is_monotonic_decreasing

    # the beginning and end values are guessed from first and last two
    start = index[0] - (index[1]-index[0])/2
    end = index[-1] + (index[-1]-index[-2])/2

    # the middle values are the midpoints
    middle = pd.DataFrame({'m1': index[:-1], 'p1': index[1:]})
    middle = middle['m1'] + (middle['p1']-middle['m1'])/2

    if isinstance(index, pd.DatetimeIndex):
        idx = pd.DatetimeIndex(middle).union([start,end])
    elif isinstance(index, (pd.Float64Index,pd.RangeIndex,pd.Int64Index)):
        idx = pd.Float64Index(middle).union([start,end])
    else:
        print('Warning: guessing what to do with index type %s' % 
              type(index))
        idx = pd.Float64Index(middle).union([start,end])

    return idx.sort_values(ascending=index.is_monotonic_increasing)

def calc_df_mesh(df):
    """Calculate the two-dimensional bins to hold the index and 
    column values."""
    return np.meshgrid(conv_index_to_bins(df.index),
                       conv_index_to_bins(df.columns))

def heatmap(df):
    """Plot a heatmap of the dataframe values using the index and 
    columns"""
    X,Y = calc_df_mesh(df)
    c = plt.pcolormesh(X, Y, df.values.T)
    plt.colorbar(c)

Call it using heatmap(df), and see it using plt.show().

enter image description here

Get total size of file in bytes

 
public static void main(String[] args) {
        try {
            File file = new File("test.txt");
            System.out.println(file.length());
        } catch (Exception e) {
        }
    }

How do I add BundleConfig.cs to my project?

BundleConfig is nothing more than bundle configuration moved to separate file. It used to be part of app startup code (filters, bundles, routes used to be configured in one class)

To add this file, first you need to add the Microsoft.AspNet.Web.Optimization nuget package to your web project:

Install-Package Microsoft.AspNet.Web.Optimization

Then under the App_Start folder create a new cs file called BundleConfig.cs. Here is what I have in my mine (ASP.NET MVC 5, but it should work with MVC 4):

using System.Web;
using System.Web.Optimization;

namespace CodeRepository.Web
{
    public class BundleConfig
    {
        // For more information on bundling, visit http://go.microsoft.com/fwlink/?LinkId=301862
        public static void RegisterBundles(BundleCollection bundles)
        {
            bundles.Add(new ScriptBundle("~/bundles/jquery").Include(
                        "~/Scripts/jquery-{version}.js"));

            bundles.Add(new ScriptBundle("~/bundles/jqueryval").Include(
                        "~/Scripts/jquery.validate*"));

            // Use the development version of Modernizr to develop with and learn from. Then, when you're
            // ready for production, use the build tool at http://modernizr.com to pick only the tests you need.
            bundles.Add(new ScriptBundle("~/bundles/modernizr").Include(
                        "~/Scripts/modernizr-*"));

            bundles.Add(new ScriptBundle("~/bundles/bootstrap").Include(
                      "~/Scripts/bootstrap.js",
                      "~/Scripts/respond.js"));

            bundles.Add(new StyleBundle("~/Content/css").Include(
                      "~/Content/bootstrap.css",
                      "~/Content/site.css"));
        }
    }
}

Then modify your Global.asax and add a call to RegisterBundles() in Application_Start():

using System.Web.Optimization;

protected void Application_Start()
{
    AreaRegistration.RegisterAllAreas();
    RouteConfig.RegisterRoutes(RouteTable.Routes);
    BundleConfig.RegisterBundles(BundleTable.Bundles);
}

A closely related question: How to add reference to System.Web.Optimization for MVC-3-converted-to-4 app

How to select option in drop down using Capybara

Here's the most concise way I've found (using capybara 3.3.0 and chromium driver):

all('#id-of-select option')[1].select_option

will select the 2nd option. Increment the index as needed.

How to preview a part of a large pandas DataFrame, in iPython notebook?

In order to view only first few entries you can use, pandas head function which is used as

dataframe.head(any number)        // default is 5
dataframe.head(n=value)

or you can also you slicing for this purpose, which can also give the same result,

dataframe[:n]

In order to view the last few entries you can use pandas tail() in a similar way,

dataframe.tail(any number)        // default is 5
dataframe.tail(n=value)

remote rejected master -> master (pre-receive hook declined)

I got the same error when I ran git status :

$ git status
On branch master
Your branch is ahead of 'origin/master' by 1 commit.
  (use "git push" to publish your local commits)
nothing to commit, working directory clean

To fix it I can run:

$ git push and run 
$ git push heroku master

MySql Error: Can't update table in stored function/trigger because it is already used by statement which invoked this stored function/trigger

You cannot change a table while the INSERT trigger is firing. The INSERT might do some locking which could result in a deadlock. Also, updating the table from a trigger would then cause the same trigger to fire again in an infinite recursive loop. Both of these reasons are why MySQL prevents you from doing this.

However, depending on what you're trying to achieve, you can access the new values by using NEW.fieldname or even the old values--if doing an UPDATE--with OLD.

If you had a row named full_brand_name and you wanted to use the first two letters as a short name in the field small_name you could use:

CREATE TRIGGER `capital` BEFORE INSERT ON `brandnames`
FOR EACH ROW BEGIN
  SET NEW.short_name = CONCAT(UCASE(LEFT(NEW.full_name,1)) , LCASE(SUBSTRING(NEW.full_name,2)))
END

Is there a "previous sibling" selector?

There isn't, and there is.

If you must place the label before the input, just place the label after the input and keep both the label & the input inside a div, and style the div as following :

_x000D_
_x000D_ 
.input-box {
  display: flex;
  flex-direction: column-reverse;
}
_x000D_ 
<div class="input-box">
  <input
   id="email"
   class="form-item"           
   />

   <label for="email" class="form-item-header">                  
   E-Mail*                  
   </label>
</div>
_x000D_
_x000D_
_x000D_

Now you can apply the standard next sibling styling options available in css, and it will appear like you are using a previous sibling styling.

SOAP Action WSDL

I have solved this problem, in Java Code, adding:

 MimeHeaders headers = message.getMimeHeaders();
 headers.addHeader("SOAPAction", endpointURL);

No module named setuptools

For python3 is:

sudo apt-get install -y python3-setuptools

Python how to plot graph sine wave

Yet another way to plot the sine wave.

import numpy as np
import matplotlib
matplotlib.use('TKAgg') #use matplotlib backend TKAgg (optional)
import matplotlib.pyplot as plt

t = np.linspace(0.0, 5.0, 50000)       # time axis
sig = np.sin(t)
plt.plot(t,sig)

How to hide .php extension in .htaccess

1) Are you sure mod_rewrite module is enabled? Check phpinfo()

2) Your above rule assumes the URL starts with "folder". Is this correct? Did you acutally want to have folder in the URL? This would match a URL like:

/folder/thing -> /folder/thing.php

If you actually want 

/thing -> /folder/thing.php

You need to drop the folder from the match expression.

I usually use this to route request to page without php (but yours should work which leads me to think that mod_rewrite may not be enabled):

RewriteRule ^([^/\.]+)/?$ $1.php  [L,QSA]

3) Assuming you are declaring your rules in an .htaccess file, does your installation allow for setting Options (AllowOverride) overrides in .htaccess files? Some shared hosts do not.

When the server finds an .htaccess file (as specified by AccessFileName) it needs to know which directives declared in that file can override earlier access information.

pandas read_csv and filter columns with usecols

import csv first and use csv.DictReader its easy to process...

postgres, ubuntu how to restart service on startup? get stuck on clustering after instance reboot

I guess it would be best to fix the database startup script itself. But as a work around, you can add that line to /etc/rc.local, which is executed about last in init phase.

change values in array when doing foreach

Javascript is pass by value, and which essentially means part is a copy of the value in the array.

To change the value, access the array itself in your loop.

arr[index] = 'new value';

Setting mime type for excel document

I am using EPPlus to generate .xlsx (OpenXML format based) excel file. For sending this excel file as attachment in email I use the following MIME type and it works fine with EPPlus generated file and opens properly in ms-outlook mail client preview.

string mimeType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
System.Net.Mime.ContentType contentType = null;
if (mimeType?.Length > 0)
{
    contentType = new System.Net.Mime.ContentType(mimeType);
}

How do I get git to default to ssh and not https for new repositories

The response provided by Trevor is correct.

But here is what you can directly add in your .gitconfig:

# Enforce SSH
[url "ssh://[email protected]/"]
  insteadOf = https://github.com/
[url "ssh://[email protected]/"]
  insteadOf = https://gitlab.com/
[url "ssh://[email protected]/"]
  insteadOf = https://bitbucket.org/

How to change the foreign key referential action? (behavior)

Old question but adding answer so that one can get help

Its two step process:

Suppose, a table1 has a foreign key with column name fk_table2_id, with constraint name fk_name and table2 is referred table with key t2 (something like below in my diagram). 

   table1 [ fk_table2_id ] --> table2 [t2]

First step, DROP old CONSTRAINT: (reference) 

ALTER TABLE `table1` 
DROP FOREIGN KEY `fk_name`;

notice constraint is deleted, column is not deleted

Second step, ADD new CONSTRAINT: 

ALTER TABLE `table1`  
ADD CONSTRAINT `fk_name` 
    FOREIGN KEY (`fk_table2_id`) REFERENCES `table2` (`t2`) ON DELETE CASCADE;

adding constraint, column is already there

Example:

I have a UserDetails table refers to Users table: 

mysql> SHOW CREATE TABLE UserDetails;
:
:
 `User_id` int(11) DEFAULT NULL,
  PRIMARY KEY (`Detail_id`),
  KEY `FK_User_id` (`User_id`),
  CONSTRAINT `FK_User_id` FOREIGN KEY (`User_id`) REFERENCES `Users` (`User_id`)
:
:

First step: 

mysql> ALTER TABLE `UserDetails` DROP FOREIGN KEY `FK_User_id`;
Query OK, 1 row affected (0.07 sec)

Second step: 

mysql> ALTER TABLE `UserDetails` ADD CONSTRAINT `FK_User_id` 
    -> FOREIGN KEY (`User_id`) REFERENCES `Users` (`User_id`) ON DELETE CASCADE;
Query OK, 1 row affected (0.02 sec)

result: 

mysql> SHOW CREATE TABLE UserDetails;
:
:
`User_id` int(11) DEFAULT NULL,
  PRIMARY KEY (`Detail_id`),
  KEY `FK_User_id` (`User_id`),
  CONSTRAINT `FK_User_id` FOREIGN KEY (`User_id`) REFERENCES 
                                       `Users` (`User_id`) ON DELETE CASCADE
:

Read from file in eclipse

I am using eclipse and I was stuck on not being able to read files because of a "file not found exception". What I did to solve this problem was I moved the file to the root of my project. Hope this helps.

What is a callback?

Probably not the dictionary definition, but a callback usually refers to a function, which is external to a particular object, being stored and then called upon a specific event.

An example might be when a UI button is created, it stores a reference to a function which performs an action. The action is handled by a different part of the code but when the button is pressed, the callback is called and this invokes the action to perform.

C#, rather than use the term 'callback' uses 'events' and 'delegates' and you can find out more about delegates here.

What is the most efficient way to store tags in a database?

Actually I believe de-normalising the tags table might be a better way forward, depending on scale.

This way, the tags table simply has tagid, itemid, tagname.

You'll get duplicate tagnames, but it makes adding/removing/editing tags for specific items MUCH more simple. You don't have to create a new tag, remove the allocation of the old one and re-allocate a new one, you just edit the tagname.

For displaying a list of tags, you simply use DISTINCT or GROUP BY, and of course you can count how many times a tag is used easily, too.

Why do I get "Pickle - EOFError: Ran out of input" reading an empty file?

You can catch that exception and return whatever you want from there. 

open(target, 'a').close()
scores = {};
try:
    with open(target, "rb") as file:
        unpickler = pickle.Unpickler(file);
        scores = unpickler.load();
        if not isinstance(scores, dict):
            scores = {};
except EOFError:
    return {}

Bash Script : what does #!/bin/bash mean?

In bash script, what does #!/bin/bash at the 1st line mean ?

In Linux system, we have shell which interprets our UNIX commands. Now there are a number of shell in Unix system. Among them, there is a shell called bash which is very very common Linux and it has a long history. This is a by default shell in Linux.

When you write a script (collection of unix commands and so on) you have a option to specify which shell it can be used. Generally you can specify which shell it wold be by using Shebang(Yes that's what it's name).

So if you #!/bin/bash in the top of your scripts then you are telling your system to use bash as a default shell.

Now coming to your second question :Is there a difference between #!/bin/bash and #!/bin/sh ?

The answer is Yes. When you tell #!/bin/bash then you are telling your environment/ os to use bash as a command interpreter. This is hard coded thing.

Every system has its own shell which the system will use to execute its own system scripts. This system shell can be vary from OS to OS(most of the time it will be bash. Ubuntu recently using dash as default system shell). When you specify #!/bin/sh then system will use it's internal system shell to interpreting your shell scripts.

Visit this link for further information where I have explained this topic.

Hope this will eliminate your confusions...good luck.

Create File If File Does Not Exist

Yes, you need to negate File.Exists(path) if you want to check if the file doesn't exist.

TreeMap sort by value

A lot of people hear adviced to use List and i prefer to use it as well

here are two methods you need to sort the entries of the Map according to their values.

    static final Comparator<Entry<?, Double>> DOUBLE_VALUE_COMPARATOR = 
        new Comparator<Entry<?, Double>>() {
            @Override
            public int compare(Entry<?, Double> o1, Entry<?, Double> o2) {
                return o1.getValue().compareTo(o2.getValue());
            }
        };

        static final List<Entry<?, Double>> sortHashMapByDoubleValue(HashMap temp)
        {
            Set<Entry<?, Double>> entryOfMap = temp.entrySet();

            List<Entry<?, Double>> entries = new ArrayList<Entry<?, Double>>(entryOfMap);
            Collections.sort(entries, DOUBLE_VALUE_COMPARATOR);
            return entries;
        }

Flatten nested dictionaries, compressing keys

This is similar to both imran's and ralu's answer. It does not use a generator, but instead employs recursion with a closure:

def flatten_dict(d, separator='_'):
  final = {}
  def _flatten_dict(obj, parent_keys=[]):
    for k, v in obj.iteritems():
      if isinstance(v, dict):
        _flatten_dict(v, parent_keys + [k])
      else:
        key = separator.join(parent_keys + [k])
        final[key] = v
  _flatten_dict(d)
  return final

>>> print flatten_dict({'a': 1, 'c': {'a': 2, 'b': {'x': 5, 'y' : 10}}, 'd': [1, 2, 3]})
{'a': 1, 'c_a': 2, 'c_b_x': 5, 'd': [1, 2, 3], 'c_b_y': 10}

How to convert JTextField to String and String to JTextField?

The JTextField offers a getText() and a setText() method - those are for getting and setting the content of the text field.

How can I add raw data body to an axios request?

You can use the below for passing the raw text.

axios.post(
        baseUrl + 'applications/' + appName + '/dataexport/plantypes' + plan, 
        body, 
        {
            headers: { 
                'Authorization': 'Basic xxxxxxxxxxxxxxxxxxx',
                'Content-Type' : 'text/plain' 
            }
        }
).then(response => {
    this.setState({data:response.data});
    console.log(this.state.data);
});

Just have your raw text within body or pass it directly within quotes as 'raw text to be sent' in place of body.

The signature of the axios post is axios.post(url[, data[, config]]), so the data is where you pass your request body.

ggplot legends - change labels, order and title

You need to do two things:

  1. Rename and re-order the factor levels before the plot
  2. Rename the title of each legend to the same title

The code:

dtt$model <- factor(dtt$model, levels=c("mb", "ma", "mc"), labels=c("MBB", "MAA", "MCC"))

library(ggplot2)
ggplot(dtt, aes(x=year, y=V, group = model, colour = model, ymin = lower, ymax = upper)) +
  geom_ribbon(alpha = 0.35, linetype=0)+ 
  geom_line(aes(linetype=model), size = 1) +       
  geom_point(aes(shape=model), size=4)  +      
  theme(legend.position=c(.6,0.8)) +
  theme(legend.background = element_rect(colour = 'black', fill = 'grey90', size = 1, linetype='solid')) +
  scale_linetype_discrete("Model 1") +
  scale_shape_discrete("Model 1") +
  scale_colour_discrete("Model 1")

enter image description here

However, I think this is really ugly as well as difficult to interpret. It's far better to use facets:

ggplot(dtt, aes(x=year, y=V, group = model, colour = model, ymin = lower, ymax = upper)) +
  geom_ribbon(alpha=0.2, colour=NA)+ 
  geom_line() +       
  geom_point()  +      
  facet_wrap(~model)

enter image description here

Loop through all elements in XML using NodeList

 
    DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
    DocumentBuilder db = dbf.newDocumentBuilder();
    Document dom = db.parse("file.xml");
    Element docEle = dom.getDocumentElement();
    NodeList nl = docEle.getChildNodes();
    int length = nl.getLength();
    for (int i = 0; i < length; i++) {
        if (nl.item(i).getNodeType() == Node.ELEMENT_NODE) {
            Element el = (Element) nl.item(i);
            if (el.getNodeName().contains("staff")) {
                String name = el.getElementsByTagName("name").item(0).getTextContent();
                String phone = el.getElementsByTagName("phone").item(0).getTextContent();
                String email = el.getElementsByTagName("email").item(0).getTextContent();
                String area = el.getElementsByTagName("area").item(0).getTextContent();
                String city = el.getElementsByTagName("city").item(0).getTextContent();
            }
        }
    }

Iterate over all children and nl.item(i).getNodeType() == Node.ELEMENT_NODE is used to filter text nodes out. If there is nothing else in XML what remains are staff nodes.

For each node under stuff (name, phone, email, area, city)

 el.getElementsByTagName("name").item(0).getTextContent();

el.getElementsByTagName("name") will extract the "name" nodes under stuff, .item(0) will get you the first node and .getTextContent() will get the text content inside.

Edit: Since we have jackson I would do this in a different way. Define a pojo for the object:

public class Staff {
    private String name;
    private String phone;
    private String email;
    private String area;
    private String city;
...getters setters
}

Then using jackson:

    JsonNode root = new XmlMapper().readTree(xml.getBytes());
    ObjectMapper mapper = new ObjectMapper();
    root.forEach(node -> consume(node, mapper));



private void consume(JsonNode node, ObjectMapper mapper) {
    try {
        Staff staff = mapper.treeToValue(node, Staff.class);
        //TODO your job with staff
    } catch (JsonProcessingException e) {
        e.printStackTrace();
    }
}

Get the system date and split day, month and year

You can split date month year from current date as follows:

DateTime todaysDate = DateTime.Now.Date;

Day:

int day = todaysDate.Day;

Month:

int month = todaysDate.Month;

Year:

int year = todaysDate.Year;

VirtualBox error "Failed to open a session for the virtual machine"

maybe it is caused by privilege, please try this:

#sudo chmod 755 /Applications 
#sudo chmod 755 /Applications/Virtualbox.app

Passing parameter using onclick or a click binding with KnockoutJS

I know this is an old question, but here is my contribution. Instead of all these tricks, you can just simply wrap a function inside another function. Like I have done here:

<div data-bind="click: function(){ f('hello parameter'); }">Click me once</div>
<div data-bind="click: function(){ f('no no parameter'); }">Click me twice</div>

var VM = function(){
   this.f = function(param){
     console.log(param);
   }
}
ko.applyBindings(new VM());

And here is the fiddle

Tensorflow set CUDA_VISIBLE_DEVICES within jupyter

You can set environment variables in the notebook using os.environ. Do the following before initializing TensorFlow to limit TensorFlow to first GPU.

import os
os.environ["CUDA_DEVICE_ORDER"]="PCI_BUS_ID"   # see issue #152
os.environ["CUDA_VISIBLE_DEVICES"]="0"

You can double check that you have the correct devices visible to TF

from tensorflow.python.client import device_lib
print device_lib.list_local_devices()

I tend to use it from utility module like notebook_util

import notebook_util
notebook_util.pick_gpu_lowest_memory()
import tensorflow as tf

Creating a border like this using :before And :after Pseudo-Elements In CSS?

See the following snippet, is this what you want?

_x000D_
_x000D_ 
body {
    background: silver;
    padding: 0 10px;
}

#content:after {
    height: 10px;
    display: block;
    width: 100px;
    background: #808080;
    border-right: 1px white;
    content: '';
}

#footer:before {
    display: block;
    content: '';
    background: silver;
    height: 10px;
    margin-top: -20px;
    margin-left: 101px;
}

#content {
    background: white;
}


#footer {
    padding-top: 10px;
    background: #404040;
}

p {
    padding: 100px;
    text-align: center;
}

#footer p {
    color: white;
}
_x000D_ 
<body>
    <div id="content"><p>#content</p></div>
    <div id="footer"><p>#footer</p></div>
</body>
_x000D_
_x000D_
_x000D_

JSFiddle

What does it mean when Statement.executeUpdate() returns -1?

For executeUpdate statements against a DB2 for z/OS server, the value that is returned depends on the type of SQL statement that is being executed:

For an SQL statement that can have an update count, such as an INSERT, UPDATE, or DELETE statement, the returned value is the number of affected rows. It can be:

A positive number, if a positive number of rows are affected by the operation, and the operation is not a mass delete on a segmented table space.

0, if no rows are affected by the operation.

-1, if the operation is a mass delete on a segmented table space.

For a DB2 CALL statement, a value of -1 is returned, because the DB2 database server cannot determine the number of affected rows. Calls to getUpdateCount or getMoreResults for a CALL statement also return -1. For any other SQL statement, a value of -1 is returned.

PHP: if !empty & empty

Here's a compact way to do something different in all four cases: 

if(empty($youtube)) {
    if(empty($link)) {
        # both empty
    } else {
        # only $youtube not empty
    }
} else {
    if(empty($link)) {
        # only $link empty
    } else {
        # both not empty
    }
}

If you want to use an expression instead, you can use ?: instead:

echo empty($youtube) ? ( empty($link) ? 'both empty' : 'only $youtube not empty' )
                     : ( empty($link) ? 'only $link empty' : 'both not empty' );

Reshaping data.frame from wide to long format

Since this answer is tagged with , I felt it would be useful to share another alternative from base R: stack.

Note, however, that stack does not work with factors--it only works if is.vector is TRUE, and from the documentation for is.vector, we find that:

is.vector returns TRUE if x is a vector of the specified mode having no attributes other than names. It returns FALSE otherwise.

I'm using the sample data from @Jaap's answer, where the values in the year columns are factors.

Here's the stack approach:

cbind(wide[1:2], stack(lapply(wide[-c(1, 2)], as.character)))
##    Code     Country values  ind
## 1   AFG Afghanistan 20,249 1950
## 2   ALB     Albania  8,097 1950
## 3   AFG Afghanistan 21,352 1951
## 4   ALB     Albania  8,986 1951
## 5   AFG Afghanistan 22,532 1952
## 6   ALB     Albania 10,058 1952
## 7   AFG Afghanistan 23,557 1953
## 8   ALB     Albania 11,123 1953
## 9   AFG Afghanistan 24,555 1954
## 10  ALB     Albania 12,246 1954

How do I add options to a DropDownList using jQuery?

With the plugin: jQuery Selection Box. You can do this:

var myOptions = {
        "Value 1" : "Text 1",
        "Value 2" : "Text 2",
        "Value 3" : "Text 3"
    }
    $("#myselect2").addOption(myOptions, false);

Count lines in large files

If your computer has python, you can try this from the shell:

python -c "print len(open('test.txt').read().split('\n'))"

This uses python -c to pass in a command, which is basically reading the file, and splitting by the "newline", to get the count of newlines, or the overall length of the file.

@BlueMoon's:

bash-3.2$ sed -n '$=' test.txt
519

Using the above:

bash-3.2$ python -c "print len(open('test.txt').read().split('\n'))"
519

How to call jQuery function onclick?

Please have a look at http://jsfiddle.net/2dJAN/59/

$("#submit").click(function () {
var url = $(location).attr('href');
$('#spn_url').html('<strong>' + url + '</strong>');
});

PHP - define constant inside a class

You can define a class constant in php. But your class constant would be accessible from any object instance as well. This is php's functionality. However, as of php7.1, you can define your class constants with access modifiers (public, private or protected).

A work around would be to define your constant as private or protected and then make them readable via a static function. This function should only return the constant values if called from the static context.

You can also create this static function in your parent class and simply inherit this parent class on all other classes to make it a default functionality.

Credits: http://dwellupper.io/post/48/defining-class-constants-in-php

setTimeout or setInterval?

I find the setTimeout method easier to use if you want to cancel the timeout:

function myTimeoutFunction() {
   doStuff();
   if (stillrunning) {
      setTimeout(myTimeoutFunction, 1000);
   }
}

myTimeoutFunction();

Also, if something would go wrong in the function it will just stop repeating at the first time error, instead of repeating the error every second.

Add element to a JSON file?

alternatively you can do 

iter(data).next()['f'] = var

Constructors in JavaScript objects

I guess I'll post what I do with javascript closure since no one is using closure yet. 

var user = function(id) {
  // private properties & methods goes here.
  var someValue;
  function doSomething(data) {
    someValue = data;
  };

  // constructor goes here.
  if (!id) return null;

  // public properties & methods goes here.
  return {
    id: id,
    method: function(params) {
      doSomething(params);
    }
  };
};

Comments and suggestions to this solution are welcome. :)

Extract directory path and filename

bash:

fspec="/exp/home1/abc.txt"
fname="${fspec##*/}"

Python - Get Yesterday's date as a string in YYYY-MM-DD format

An alternative answer that uses today() method to calculate current date and then subtracts one using timedelta(). Rest of the steps remain the same.

https://docs.python.org/3.7/library/datetime.html#timedelta-objects

from datetime import date, timedelta
today = date.today()
yesterday = today - timedelta(days = 1)
print(today)
print(yesterday)

Output: 
2019-06-14
2019-06-13

Rails - passing parameters in link_to

 
link_to "+ Service", controller_action_path(:account_id => acct.id)

If it is still not working check the path:

$ rake routes

CSS: stretching background image to 100% width and height of screen?

You need to set the height of html to 100%

body {
    background-image:url("../images/myImage.jpg");
    background-repeat: no-repeat;
    background-size: 100% 100%;
}
html {
    height: 100%
}

http://jsfiddle.net/8XUjP/

How can I get query string values in JavaScript?

If you do not wish to use a JavaScript library you can use the JavaScript string functions to parse window.location. Keep this code in an external .js file and you can use it over and over again in different projects.

// Example - window.location = "index.htm?name=bob";

var value = getParameterValue("name");

alert("name = " + value);

function getParameterValue(param)
{
    var url = window.location;
    var parts = url.split('?');
    var params = parts[1].split('&');
    var val = "";

    for ( var i=0; i<params.length; i++)
    {
        var paramNameVal = params[i].split('=');

        if ( paramNameVal[0] == param )
        {
            val = paramNameVal[1];
        }
    }
    return val;
}

What REST PUT/POST/DELETE calls should return by a convention?

Forgive the flippancy, but if you are doing REST over HTTP then RFC7231 describes exactly what behaviour is expected from GET, PUT, POST and DELETE.

Update (Jul 3 '14):
The HTTP spec intentionally does not define what is returned from POST or DELETE. The spec only defines what needs to be defined. The rest is left up to the implementer to choose.

How to tell which disk Windows Used to Boot

a simpler way search downloads in the start menu and click on downloads in the search results to see where it will take you the drive will be highlighted in the explorer.

How to increment variable under DOS?

Indeed, set in DOS has no option to allow for arithmetic. You could do a giant lookup table, though:

if %COUNTER%==249 set COUNTER=250
...
if %COUNTER%==3 set COUNTER=4
if %COUNTER%==2 set COUNTER=3
if %COUNTER%==1 set COUNTER=2
if %COUNTER%==0 set COUNTER=1

Changing the "tick frequency" on x or y axis in matplotlib?

 
xmarks=[i for i in range(1,length+1,1)]

plt.xticks(xmarks)

This worked for me

if you want ticks between [1,5] (1 and 5 inclusive) then replace 

length = 5

is there any alternative for ng-disabled in angular2?

To set the disabled property to true or false use

<button [disabled]="!nextLibAvailable" (click)="showNext('library')" class=" btn btn-info btn-xs" title="Next Lib"> {{libraries.name}}">
    <i class="fa fa-chevron-right fa-fw"></i>
</button>

How do you use a variable in a regular expression?

 
this.replace( new RegExp( replaceThis, 'g' ), withThis );

What is the "-->" operator in C/C++?

Utterly geek, but I will be using this:

#define as ;while

int main(int argc, char* argv[])
{
    int n = atoi(argv[1]);
    do printf("n is %d\n", n) as ( n --> 0);
    return 0;
}

ASP.Net MVC - Read File from HttpPostedFileBase without save

This can be done using httpPostedFileBase class returns the HttpInputStreamObject as per specified here

You should convert the stream into byte array and then you can read file content

Please refer following link

http://msdn.microsoft.com/en-us/library/system.web.httprequest.inputstream.aspx]

Hope this helps

UPDATE :

The stream that you get from your HTTP call is read-only sequential (non-seekable) and the FileStream is read/write seekable. You will need first to read the entire stream from the HTTP call into a byte array, then create the FileStream from that array.

Taken from here

// Read bytes from http input stream
BinaryReader b = new BinaryReader(file.InputStream);
byte[] binData = b.ReadBytes(file.ContentLength);

string result = System.Text.Encoding.UTF8.GetString(binData);

How to make PyCharm always show line numbers

For version 2.6 and up, the dialog is in the "Preferences" dialog, access using Cmd ',':

PyCharm (far left menu) -> Preferences... -> Editor (bottom left section) -> Appearance -> Show line numbers checkbox

How can I detect Internet Explorer (IE) and Microsoft Edge using JavaScript?

I'm using UAParser https://github.com/faisalman/ua-parser-js

var a = new UAParser();
var name = a.getResult().browser.name;
var version = a.getResult().browser.version;

MySQL string replace

In addition to gmaggio's answer if you need to dynamically REPLACE and UPDATE according to another column you can do for example:

UPDATE your_table t1
INNER JOIN other_table t2
ON t1.field_id = t2.field_id
SET t1.your_field = IF(LOCATE('articles/updates/', t1.your_field) > 0, 
REPLACE(t1.your_field, 'articles/updates/', t2.new_folder), t1.your_field) 
WHERE...

In my example the string articles/news/ is stored in other_table t2 and there is no need to use LIKE in the WHERE clause.

How do I make a textbox that only accepts numbers?

 
int Number;
bool isNumber;
isNumber = int32.TryPase(textbox1.text, out Number);

if (!isNumber)
{ 
    (code if not an integer);
}
else
{
    (code if an integer);
}

Difference between thread's context class loader and normal classloader

This does not answer the original question, but as the question is highly ranked and linked for any ContextClassLoader query, I think it is important to answer the related question of when the context class loader should be used. Short answer: never use the context class loader! But set it to getClass().getClassLoader() when you have to call a method that is missing a ClassLoader parameter.

When code from one class asks to load another class, the correct class loader to use is the same class loader as the caller class (i.e., getClass().getClassLoader()). This is the way things work 99.9% of the time because this is what the JVM does itself the first time you construct an instance of a new class, invoke a static method, or access a static field.

When you want to create a class using reflection (such as when deserializing or loading a configurable named class), the library that does the reflection should always ask the application which class loader to use, by receiving the ClassLoader as a parameter from the application. The application (which knows all the classes that need constructing) should pass it getClass().getClassLoader().

Any other way to obtain a class loader is incorrect. If a library uses hacks such as Thread.getContextClassLoader(), sun.misc.VM.latestUserDefinedLoader(), or sun.reflect.Reflection.getCallerClass() it is a bug caused by a deficiency in the API. Basically, Thread.getContextClassLoader() exists only because whoever designed the ObjectInputStream API forgot to accept the ClassLoader as a parameter, and this mistake has haunted the Java community to this day.

That said, many many JDK classes use one of a few hacks to guess some class loader to use. Some use the ContextClassLoader (which fails when you run different apps on a shared thread pool, or when you leave the ContextClassLoader null), some walk the stack (which fails when the direct caller of the class is itself a library), some use the system class loader (which is fine, as long as it is documented to only use classes in the CLASSPATH) or bootstrap class loader, and some use an unpredictable combination of the above techniques (which only makes things more confusing). This has resulted in much weeping and gnashing of teeth.

When using such an API, first, try to find an overload of the method that accepts the class loader as a parameter. If there is no sensible method, then try setting the ContextClassLoader before the API call (and resetting it afterwards):

ClassLoader originalClassLoader = Thread.currentThread().getContextClassLoader();
try {
    Thread.currentThread().setContextClassLoader(getClass().getClassLoader());
    // call some API that uses reflection without taking ClassLoader param
} finally {
    Thread.currentThread().setContextClassLoader(originalClassLoader);
}

Resize on div element

Only window is supported yes but you could use a plugin for it: http://benalman.com/projects/jquery-resize-plugin/

Moving from JDK 1.7 to JDK 1.8 on Ubuntu

This is what I do on debian - I suspect it should work on ubuntu (amend the version as required + adapt the folder where you want to copy the JDK files as you wish, I'm using /opt/jdk):

wget --header "Cookie: oraclelicense=accept-securebackup-cookie" http://download.oracle.com/otn-pub/java/jdk/8u71-b15/jdk-8u71-linux-x64.tar.gz
sudo mkdir /opt/jdk
sudo tar -zxf jdk-8u71-linux-x64.tar.gz -C /opt/jdk/
rm jdk-8u71-linux-x64.tar.gz

Then update-alternatives:

sudo update-alternatives --install /usr/bin/java java /opt/jdk/jdk1.8.0_71/bin/java 1
sudo update-alternatives --install /usr/bin/javac javac /opt/jdk/jdk1.8.0_71/bin/javac 1

Select the number corresponding to the /opt/jdk/jdk1.8.0_71/bin/java when running the following commands:

sudo update-alternatives --config java
sudo update-alternatives --config javac

Finally, verify that the correct version is selected:

java -version
javac -version

check if file exists on remote host with ssh

Here is a simple approach:

#!/bin/bash
USE_IP='-o StrictHostKeyChecking=no [email protected]'

FILE_NAME=/home/user/file.txt

SSH_PASS='sshpass -p password-for-remote-machine'

if $SSH_PASS ssh $USE_IP stat $FILE_NAME \> /dev/null 2\>\&1
            then
                    echo "File exists"
            else
                    echo "File does not exist"

fi

You need to install sshpass on your machine to work it.

Customize UITableView header section

If I were you, I would make a method which returns an UIView given a NSString to contain. For example

+ (UIView *) sectionViewWithTitle:(NSString *)title;

In the implementation of this method create a UIView, add a UILabel to it with the properties you want to set, and of course set its title to the given one.

rm: cannot remove: Permission denied

The code says everything:

max@serv$ chmod 777 .

Okay, it doesn't say everything.

In UNIX and Linux, the ability to remove a file is not determined by the access bits of that file. It is determined by the access bits of the directory which contains the file.

Think of it this way -- deleting a file doesn't modify that file. You aren't writing to the file, so why should "w" on the file matter? Deleting a file requires editing the directory that points to the file, so you need "w" on the that directory.

htaccess "order" Deny, Allow, Deny

Update : for the new apache 2.4 jump directly to the end.

The Order keyword and its relation with Deny and Allow Directives is a real nightmare. It would be quite interesting to understand how we ended up with such solution, a non-intuitive one to say the least.

  • The first important point is that the Order keyword will have a big impact on how Allow and Deny directives are used.
  • Secondly, Deny and Allow directives are not applied in the order they are written, they must be seen as two distinct blocks (one the for Deny directives, one for Allow).
  • Thirdly, they are drastically not like firewall rules: all rules are applied, the process is not stopping at the first match.

You have two main modes:

The Order-Deny-Allow-mode, or Allow-anyone-except-this-list-or-maybe-not

Order Deny,Allow
  • This is an allow by default mode. You optionally specify Deny rules.
  • Firstly, the Deny rules reject some requests.
  • If someone gets rejected you can get them back with an Allow.

I would rephrase it as:

Rule Deny
     list of Deny rules
Except
     list of Allow rules
Policy Allow (when no rule fired)

The Order-Allow-Deny-mode, or Reject-everyone-except-this-list-or-maybe-not

Order Allow,Deny
  • This is a deny by default mode. So you usually specify Allow rules.
  • Firstly, someone's request must match at least one Allow rule.
  • If someone matched an Allow, you can still reject them with a Deny.

In the simplified form:

Rule Allow
     list of Allow rules
Except
     list of Deny rules
Policy Deny (when no rule fired)

Back to your case

You need to allow a list of networks which are the country networks. And in this country you want to exclude some proxies' IP addresses.

You have taken the allow-anyone-except-this-list-or-maybe-not mode, so by default anyone can access your server, except proxies' IPs listed in the Deny list, but if they get rejected you still allow the country networks. That's too broad. Not good.

By inverting to order allow,deny you will be in the reject-everyone-except-this-list-or-maybe-not mode. So you will reject access to everyone but allow the country networks and then you will reject the proxies. And of course you must remove the Deny from all as stated by @Gerben and @Michael Slade (this answer only explains what they wrote).

The Deny from all is usually seen with order deny,allow to remove the allow by default access and make a simple, readable configuration. For example, specify a list of allowed IPs after that. You don't need that rule and your question is a perfect case of a 3-way access mode (default policy, exceptions, exceptions to exceptions).

But the guys who designed these settings are certainly insane.

All this is deprecated with Apache 2.4

The whole authorization scheme has been refactored in Apache 2.4 with RequireAll, RequireAny and RequireNone directives. See for example this complex logic example.

So the old strange Order logic becomes a relic, and to quote the new documentation:

Controling how and in what order authorization will be applied has been a bit of a mystery in the past

How to replace comma (,) with a dot (.) using java

 
if(str.indexOf(",")!=-1) { str = str.replaceAll(",","."); }

or even better

str = str.replace(',', '.');

Sorting rows in a data table

This will help you...

DataTable dt = new DataTable();         
dt.DefaultView.Sort = "Column_name desc";
dt = dt.DefaultView.ToTable();

Modifying list while iterating

I guess this is what you want:

l  = range(100)  
index = 0                       
for i in l:                         
    print i,              
    try:
        print l.pop(index+1),                  
        print l.pop(index+1)
    except:
        pass
    index += 1

It is quite handy to code when the number of item to be popped is a run time decision. But it runs with very a bad efficiency and the code is hard to maintain.

CSS: How to change colour of active navigation page menu

I think you are getting confused about what the a:active CSS selector does. This will only change the colour of your link when you click it (and only for the duration of the click i.e. how long your mouse button stays down). What you need to do is introduce a new class e.g. .selected into your CSS and when you select a link, update the selected menu item with new class e.g.

<div class="menuBar">
    <ul>
        <li class="selected"><a href="index.php">HOME</a></li>
        <li><a href="two.php">PORTFOLIO</a></li>
        ....
    </ul>
</div>

// specific CSS for your menu
div.menuBar li.selected a { color: #FF0000; } 
// more general CSS
li.selected a { color: #FF0000; }

You will need to update your template page to take in a selectedPage parameter.

Add space between two particular <td>s

td:nth-of-type(n) { padding-right: 10px;}

it will adjust auto space between all td

How to check if "Radiobutton" is checked?

Simple Solution

radioSection.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
          @Override
          public void onCheckedChanged(RadioGroup group1, int checkedId1) {
              switch (checkedId1) {
                  case R.id.rbSr://radiobuttonID
                      //do what you want
                      break;
                  case R.id.rbJr://radiobuttonID
                      //do what you want
                      break;
              }
          }
      });

mysqli_connect(): (HY000/2002): No connection could be made because the target machine actively refused it

I finally found a solution. I wasted hours just trying to figure what this issue was. I tried deleting all those files suggested above and it didn't work for me, I tried adding new inbound rules to firewall for myslqd.exe and it didn't work. The thing that is causing this error is MySQL port is misconfigured and the fix was really simple. if you are using Wamp or Xampp go to Main Folder/Bin/mysql/mysql/ and find a file named my.ini

Open my.ini file press CTRL + F and inside it search for PORT and change whatever value of port to - 3306 and save file;

After that go to Wamp icon at the bottom of the taskbar (system tray) and left click choose mysql option and click "test port 3306 used" and see if it gives you any error. you can also click use other port other than whatever is shown there and port 3306.

Goodluck. if it works comment.

enter image description here

Check if a file exists or not in Windows PowerShell?

You can use the Test-Path cmd-let. So something like...

if(!(Test-Path [oldLocation]) -and !(Test-Path [newLocation]))
{
    Write-Host "$file doesn't exist in both locations."
}

For each row in an R dataframe

you can do something for a list object,

data("mtcars")
rownames(mtcars)
data <- list(mtcars ,mtcars, mtcars, mtcars);data

out1 <- NULL 
for(i in seq_along(data)) { 
  out1[[i]] <- data[[i]][rownames(data[[i]]) != "Volvo 142E", ] } 
out1

Or a data frame,

data("mtcars")
df <- mtcars
out1 <- NULL 
for(i in 1:nrow(df)) {
  row <- rownames(df[i,])
  # do stuff with row
  out1 <- df[rownames(df) != "Volvo 142E",]
  
}
out1

Is there a Java API that can create rich Word documents?

Try Aspose.Words for java.

Aspose.Words for Java is an advanced (commercial) class library for Java that enables you to perform a great range of document processing tasks directly within your Java applications.

Aspose.Words for Java supports DOC, OOXML, RTF, HTML and OpenDocument formats. With Aspose.Words you can generate, modify, and convert documents without using Microsoft Word.

Common elements in two lists

You can get the common elements between two lists using the method "retainAll". This method will remove all unmatched elements from the list to which it applies.

Ex.: list.retainAll(list1);

In this case from the list, all the elements which are not in list1 will be removed and only those will be remaining which are common between list and list1.

List<Integer> list = new ArrayList<>();
list.add(10);
list.add(13);
list.add(12);
list.add(11);

List<Integer> list1 = new ArrayList<>();
list1.add(10);
list1.add(113);
list1.add(112);
list1.add(111);
//before retainAll
System.out.println(list);
System.out.println(list1);
//applying retainAll on list
list.retainAll(list1);
//After retainAll
System.out.println("list::"+list);
System.out.println("list1::"+list1);

Output: 

[10, 13, 12, 11]
[10, 113, 112, 111]
list::[10]
list1::[10, 113, 112, 111]

NOTE: After retainAll applied on the list, the list contains common element between list and list1.

Sort an array of objects in React and render them

You will need to sort your object before mapping over them. And it can be done easily with a sort() function with a custom comparator definition like

var obj = [...this.state.data];
obj.sort((a,b) => a.timeM - b.timeM);
obj.map((item, i) => (<div key={i}> {item.matchID}  
                      {item.timeM} {item.description}</div>))

How to output HTML from JSP <%! ... %> block?

You can do something like this:

<%!
String myMethod(String input) {
    return "test " + input;
}
%>

<%= myMethod("1 2 3") %>

This will output test 1 2 3 to the page.

Getting the current date in SQL Server?

 
SELECT CAST(GETDATE() AS DATE)

Returns the current date with the time part removed.

DATETIMEs are not "stored in the following format". They are stored in a binary format. 

SELECT CAST(GETDATE() AS BINARY(8))

The display format in the question is independent of storage.

Formatting into a particular display format should be done by your application.

How to create a .NET DateTime from ISO 8601 format

This solution makes use of the DateTimeStyles enumeration, and it also works with Z.

DateTime d2 = DateTime.Parse("2010-08-20T15:00:00Z", null, System.Globalization.DateTimeStyles.RoundtripKind);

This prints the solution perfectly.

The term "Add-Migration" is not recognized

In my case I added dependency via Nuget:

Microsoft.EntityFrameworkCore.Tools

And then run via Package Manager Console:

add-migration Initial -Context "ContextName" -StartupProject "EntryProject.Name" -Project "MigrationProject.Name"

Call async/await functions in parallel

TL;DR

Use Promise.all for the parallel function calls, the answer behaviors not correctly when the error occurs.

First, execute all the asynchronous calls at once and obtain all the Promise objects. Second, use await on the Promise objects. This way, while you wait for the first Promise to resolve the other asynchronous calls are still progressing. Overall, you will only wait for as long as the slowest asynchronous call. For example:

// Begin first call and store promise without waiting
const someResult = someCall();

// Begin second call and store promise without waiting
const anotherResult = anotherCall();

// Now we await for both results, whose async processes have already been started
const finalResult = [await someResult, await anotherResult];

// At this point all calls have been resolved
// Now when accessing someResult| anotherResult,
// you will have a value instead of a promise

JSbin example: http://jsbin.com/xerifanima/edit?js,console

Caveat: It doesn't matter if the await calls are on the same line or on different lines, so long as the first await call happens after all of the asynchronous calls. See JohnnyHK's comment.

Update: this answer has a different timing in error handling according to the @bergi's answer, it does NOT throw out the error as the error occurs but after all the promises are executed. I compare the result with @jonny's tip: [result1, result2] = Promise.all([async1(), async2()]), check the following code snippet

_x000D_
_x000D_ 
const correctAsync500ms = () => {_x000D_
  return new Promise(resolve => {_x000D_
    setTimeout(resolve, 500, 'correct500msResult');_x000D_
  });_x000D_
};_x000D_
_x000D_
const correctAsync100ms = () => {_x000D_
  return new Promise(resolve => {_x000D_
    setTimeout(resolve, 100, 'correct100msResult');_x000D_
  });_x000D_
};_x000D_
_x000D_
const rejectAsync100ms = () => {_x000D_
  return new Promise((resolve, reject) => {_x000D_
    setTimeout(reject, 100, 'reject100msError');_x000D_
  });_x000D_
};_x000D_
_x000D_
const asyncInArray = async (fun1, fun2) => {_x000D_
  const label = 'test async functions in array';_x000D_
  try {_x000D_
    console.time(label);_x000D_
    const p1 = fun1();_x000D_
    const p2 = fun2();_x000D_
    const result = [await p1, await p2];_x000D_
    console.timeEnd(label);_x000D_
  } catch (e) {_x000D_
    console.error('error is', e);_x000D_
    console.timeEnd(label);_x000D_
  }_x000D_
};_x000D_
_x000D_
const asyncInPromiseAll = async (fun1, fun2) => {_x000D_
  const label = 'test async functions with Promise.all';_x000D_
  try {_x000D_
    console.time(label);_x000D_
    let [value1, value2] = await Promise.all([fun1(), fun2()]);_x000D_
    console.timeEnd(label);_x000D_
  } catch (e) {_x000D_
    console.error('error is', e);_x000D_
    console.timeEnd(label);_x000D_
  }_x000D_
};_x000D_
_x000D_
(async () => {_x000D_
  console.group('async functions without error');_x000D_
  console.log('async functions without error: start')_x000D_
  await asyncInArray(correctAsync500ms, correctAsync100ms);_x000D_
  await asyncInPromiseAll(correctAsync500ms, correctAsync100ms);_x000D_
  console.groupEnd();_x000D_
_x000D_
  console.group('async functions with error');_x000D_
  console.log('async functions with error: start')_x000D_
  await asyncInArray(correctAsync500ms, rejectAsync100ms);_x000D_
  await asyncInPromiseAll(correctAsync500ms, rejectAsync100ms);_x000D_
  console.groupEnd();_x000D_
})();
_x000D_
_x000D_
_x000D_

Launch Image does not show up in my iOS App

I just figured this out. My launch image was not showing up, I get a white screen when launching on a device (iPhone 6, 7+) or testFlight. Fix: Renamed "Landing_screen.png" to just "Landing_screen" removing .png part. The image icon in Xcode changed to white icon and in the launch screen storyboard the image appears as a question mark now. The Launch image now appears and not the white screen. My Setup: I am using Swift 3.1 with Xcode 8.3.1. In LaunchScreen.storyboard I added a simple image view and stretched the image to fit the view controller. I set auto layout constraints Top/Bottom/Leading/Trailing space to superview to 0.

What is the equivalent to a JavaScript setInterval/setTimeout in Android/Java?

Here's a setTimeout equivalent, mostly useful when trying to update the User Interface after a delay.

As you may know, updating the user interface can only by done from the UI thread. AsyncTask does that for you by calling its onPostExecute method from that thread.

new AsyncTask<Void, Void, Void>() {
        @Override
        protected Void doInBackground(Void... params) {
            try {
                Thread.sleep(5000);
            } catch (InterruptedException e) {
            }

            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            // Update the User Interface
        }

    }.execute();

How to create/read/write JSON files in Qt5

Sadly, many JSON C++ libraries have APIs that are non trivial to use, while JSON was intended to be easy to use.

So I tried jsoncpp from the gSOAP tools on the JSON doc shown in one of the answers above and this is the code generated with jsoncpp to construct a JSON object in C++ which is then written in JSON format to std::cout:

value x(ctx);
x["appDesc"]["description"] = "SomeDescription";
x["appDesc"]["message"] = "SomeMessage";
x["appName"]["description"] = "Home";
x["appName"]["message"] = "Welcome";
x["appName"]["imp"][0] = "awesome";
x["appName"]["imp"][1] = "best";
x["appName"]["imp"][2] = "good";
std::cout << x << std::endl;

and this is the code generated by jsoncpp to parse JSON from std::cin and extract its values (replace USE_VAL as needed):

value x(ctx);
std::cin >> x;
if (x.soap->error)
  exit(EXIT_FAILURE); // error parsing JSON
#define USE_VAL(path, val) std::cout << path << " = " << val << std::endl
if (x.has("appDesc"))
{
  if (x["appDesc"].has("description"))
    USE_VAL("$.appDesc.description", x["appDesc"]["description"]);
  if (x["appDesc"].has("message"))
    USE_VAL("$.appDesc.message", x["appDesc"]["message"]);
}
if (x.has("appName"))
{
  if (x["appName"].has("description"))
    USE_VAL("$.appName.description", x["appName"]["description"]);
  if (x["appName"].has("message"))
    USE_VAL("$.appName.message", x["appName"]["message"]);
  if (x["appName"].has("imp"))
  {
    for (int i2 = 0; i2 < x["appName"]["imp"].size(); i2++)
      USE_VAL("$.appName.imp[]", x["appName"]["imp"][i2]);
  }
}

This code uses the JSON C++ API of gSOAP 2.8.28. I don't expect people to change libraries, but I think this comparison helps to put JSON C++ libraries in perspective.

Setting a timeout for socket operations

Use the Socket() constructor, and connect(SocketAddress endpoint, int timeout) method instead.

In your case it would look something like:

Socket socket = new Socket();
socket.connect(new InetSocketAddress(ipAddress, port), 1000);

Quoting from the documentation

connect

public void connect(SocketAddress endpoint, int timeout) throws IOException

Connects this socket to the server with a specified timeout value. A timeout of zero is interpreted as an infinite timeout. The connection will then block until established or an error occurs.

Parameters:

endpoint - the SocketAddress
timeout - the timeout value to be used in milliseconds.

Throws:

IOException - if an error occurs during the connection
SocketTimeoutException - if timeout expires before connecting
IllegalBlockingModeException - if this socket has an associated channel, and the channel is in non-blocking mode
IllegalArgumentException - if endpoint is null or is a SocketAddress subclass not supported by this socket

Since: 1.4

Check if a string contains a string in C++

You can try using the find function:

string str ("There are two needles in this haystack.");
string str2 ("needle");

if (str.find(str2) != string::npos) {
//.. found.
}

Can't subtract offset-naive and offset-aware datetimes

You don't need anything outside the std libs

datetime.datetime.now().astimezone()

If you just replace the timezone it will not adjust the time. If your system is already UTC then .replace(tz='UTC') is fine.

>>> x=datetime.datetime.now()
datetime.datetime(2020, 11, 16, 7, 57, 5, 364576)

>>> print(x)
2020-11-16 07:57:05.364576

>>> print(x.astimezone()) 
2020-11-16 07:57:05.364576-07:00

>>> print(x.replace(tzinfo=datetime.timezone.utc)) # wrong
2020-11-16 07:57:05.364576+00:00

How do I get the first n characters of a string without checking the size or going out of bounds?

Don't reinvent the wheel...:

org.apache.commons.lang.StringUtils.substring(String s, int start, int len)

Javadoc says:

StringUtils.substring(null, *, *)    = null
StringUtils.substring("", * ,  *)    = "";
StringUtils.substring("abc", 0, 2)   = "ab"
StringUtils.substring("abc", 2, 0)   = ""
StringUtils.substring("abc", 2, 4)   = "c"
StringUtils.substring("abc", 4, 6)   = ""
StringUtils.substring("abc", 2, 2)   = ""
StringUtils.substring("abc", -2, -1) = "b"
StringUtils.substring("abc", -4, 2)  = "ab"

Thus:

StringUtils.substring("abc", 0, 4) = "abc"

How to write a multiline command?

If you came here looking for an answer to this question but not exactly the way the OP meant, ie how do you get multi-line CMD to work in a single line, I have a sort of dangerous answer for you.

Trying to use this with things that actually use piping, like say findstr is quite problematic. The same goes for dealing with elses. But if you just want a multi-line conditional command to execute directly from CMD and not via a batch file, this should do work well.

Let's say you have something like this in a batch that you want to run directly in command prompt: 

@echo off
for /r %%T IN (*.*) DO (
    if /i "%%~xT"==".sln" (
        echo "%%~T" is a normal SLN file, and not a .SLN.METAPROJ or .SLN.PROJ file
        echo Dumping SLN file contents
        type "%%~T"
    )
)

Now, you could use the line-continuation carat (^) and manually type it out like this, but warning, it's tedious and if you mess up you can learn the joy of typing it all out again.

Well, it won't work with just ^ thanks to escaping mechanisms inside of parentheses shrug At least not as-written. You actually would need to double up the carats like so:

@echo off ^
More? for /r %T IN (*.sln) DO (^^
More? if /i "%~xT"==".sln" (^^
More? echo "%~T" is a normal SLN file, and not a .SLN.METAPROJ or .SLN.PROJ file^^
More? echo Dumping SLN file contents^^
More? type "%~T"))

Instead, you can be a dirty sneaky scripter from the wrong side of the tracks that don't need no carats by swapping them out for a single pipe (|) per continuation of a loop/expression: 

@echo off
for /r %T IN (*.sln) DO if /i "%~xT"==".sln" echo "%~T" is a normal SLN file, and not a .SLN.METAPROJ or .SLN.PROJ file | echo Dumping SLN file contents | type "%~T"

changing source on html5 video tag

Another way you can do in Jquery.

HTML

<video id="videoclip" controls="controls" poster="" title="Video title">
    <source id="mp4video" src="video/bigbunny.mp4" type="video/mp4"  />
</video>

<div class="list-item">
     <ul>
         <li class="item" data-video = "video/bigbunny.mp4"><a href="javascript:void(0)">Big Bunny.</a></li>
     </ul>
</div>

Jquery

$(".list-item").find(".item").on("click", function() {
        let videoData = $(this).data("video");
        let videoSource = $("#videoclip").find("#mp4video");
        videoSource.attr("src", videoData);
        let autoplayVideo = $("#videoclip").get(0);
        autoplayVideo.load();
        autoplayVideo.play();
    });

How to set MouseOver event/trigger for border in XAML?

Yes, this is confusing...

According to this blog post, it looks like this is an omission from WPF.

To make it work you need to use a style:

    <Border Name="ClearButtonBorder" Grid.Column="1" CornerRadius="0,3,3,0">
        <Border.Style>
            <Style>
                <Setter Property="Border.Background" Value="Blue"/>
                <Style.Triggers>
                    <Trigger Property="Border.IsMouseOver" Value="True">
                        <Setter Property="Border.Background" Value="Green" />
                    </Trigger>
                </Style.Triggers>
            </Style>
        </Border.Style>
        <TextBlock HorizontalAlignment="Center" VerticalAlignment="Center" Text="X" />
    </Border>

I guess this problem isn't that common as most people tend to factor out this sort of thing into a style, so it can be used on multiple controls.

Force div element to stay in same place, when page is scrolled

Use position: fixed instead of position: absolute.

See here.

Switching a DIV background image with jQuery

This is a fairly simple response changes the background of the site with a list of items

function randomToN(maxVal) {
    var randVal = Math.random() * maxVal;
    return typeof 0 == 'undefined' ? Math.round(randVal) : randVal.toFixed(0);
};
var list = [ "IMG0.EXT", "IMG2.EXT","IMG3.EXT" ], // Images
    ram = list[parseFloat(randomToN(list.length))], // Random 1 to n
    img = ram == undefined || ram == null ? list[0] : ram; // Detect null
$("div#ID").css("backgroundImage", "url(" + img + ")"); // push de background

MySQL stored procedure vs function, which would I use when?

Stored procedure can be called recursively but stored function can not

Error: macro names must be identifiers using #ifdef 0

Note that you can also hit this error if you accidentally type:

#define <stdio.h>

...instead of...

#include <stdio.>

Using HeapDumpOnOutOfMemoryError parameter for heap dump for JBoss

You can view this dump from the UNIX console.

The path for the heap dump will be provided as a variable right after where you have placed the mentioned variable.

E.g.:

-XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=${DOMAIN_HOME}/logs/mps"

You can view the dump from the console on the mentioned path.

How can I change a button's color on hover?

 
a.button:hover{
    background: #383;  }

works for me but in my case

#buttonClick:hover {
background-color:green;  }

How do you run a SQL Server query from PowerShell?

You can use the Invoke-Sqlcmd cmdlet

Invoke-Sqlcmd -Query "SELECT GETDATE() AS TimeOfQuery;" -ServerInstance "MyComputer\MyInstance"

http://technet.microsoft.com/en-us/library/cc281720.aspx

"unrecognized import path" with go get

The most common causes are:
1. An incorrectly configured GOROOT
OR
2. GOPATH is not set

I can’t find the Android keytool

The 4-Step Answer above worked for me, but it returns the SH1-key... but Google asks for the MD5-key to generate your API key.

One needs simply to add a '-v' in the command in step 3. -like so:

Updated 4-Step Answer

Ok I did this in Windows 7 32-bit system.

step 1: go to - C:\Program Files\Java\jdk1.7.0\bin - and run jarsigner.exe first ( double click)

step2: locate debug.keystore (in Eclipse: Windows/Preferences/Android/build..), in my case it was - C:\Users\MyPcName.android

step3: open command prompt and go to dir - C:\Program Files\Java\jdk1.7.0\bin and give the following command: keytool -v -list -keystore "C:\Users\MyPcName.android\debug.keystore"

step4: it will ask for Keystore password now. The default is 'android'

Is it better to use path() or url() in urls.py for django 2.0?

From v2.0 many users are using path, but we can use either path or url. For example in django 2.1.1 mapping to functions through url can be done as follows

from django.contrib import admin
from django.urls import path

from django.contrib.auth import login
from posts.views import post_home
from django.conf.urls import url

urlpatterns = [
    path('admin/', admin.site.urls),
    url(r'^posts/$', post_home, name='post_home'),

]

where posts is an application & post_home is a function in views.py

UnsatisfiedDependencyException: Error creating bean with name 'entityManagerFactory'

The MySQL dependency should be like the following syntax in the pom.xml file.

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.21</version>
    </dependency>

Make sure the syntax, groupId, artifactId, Version has included in the dependancy.

How do SETLOCAL and ENABLEDELAYEDEXPANSION work?

A real problem often exists because any variables set inside will not be exported when that batch file finishes. So its not possible to export, which caused us issues. As a result, I just set the registry to ALWAYS used delayed expansion (I don't know why it's not the default, could be speed or legacy compatibility issue.)

Get IPv4 addresses from Dns.GetHostEntry()

IPv6

lblIP.Text = System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName).AddressList(0).ToString()


IPv4

lblIP.Text = System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName).AddressList(1).ToString()

How to get the path of src/test/resources directory in JUnit?

There are differences and constraints in options offered by @Steve C and @ashosborne1. They must be specified, I believe.

When can we can use: File resourcesDirectory = new File("src/test/resources");?

  • 1 When tests are going to be run via maven only but not via IDE.
  • 2.1 When tests are going to be run via maven or
  • 2.2 via IDE and only one project is imported into IDE. (I use “imported” term, cause it is used in IntelliJ IDEA. I think users of eclipse also import their maven project). This will work, cause working directory when you run tests via IDE is the same as your project.
  • 3.1 When tests are going to be run via maven or
  • 3.2 via IDE, and more than one projects are imported into IDE (when you are not a student, you usually import several projects), AND before you run tests via IDE, you manually configure working directory for your tests. That working directory should refer to your imported project that contains the tests. By default, working directory of all projects imported into IDE is only one. Probably it is a restriction of IntelliJ IDEA only, but I think all IDEs work like this. And this configuration that must be done manually, is not good at all. Working with several tests existing in different maven projects, but imported into one big “IDE” project, force us to remember this and don’t allow to relax and get pleasure from your work.

Solution offered by @ashosborne1 (personally I prefer this one) requires 2 additional requirements that must be done before you run tests. Here is a list of steps to use this solution:

  • Create a test folder (“teva”) and file (“readme”) inside of “src/test/resources/”:

    src/test/resources/teva/readme

    File must be created in the test folder, otherwise, it will not work. Maven ignores empty folders.

  • At least once build project via mvn clean install. It will run tests also. It may be enough to run only your test class/method via maven without building a whole project. As a result your test resources will be copied into test-classes, here is a path: target/test-classes/teva/readme

  • After that, you can access the folder using code, already offered by @ashosborne1 (I'm sorry, that I could not edit this code inside of this list of items correctly):

public static final String TEVA_FOLDER = "teva"; ... 
URL tevaUrl = YourTest.class.getClassLoader().getResource(TEVA_FOLDER); 
String tevaTestFolder = new File(tevaUrl.toURI()).getAbsolutePath();

Now you can run your test via IDE as many times as you want. Until you run mvn clean. It will drop the target folder.

Creating file inside a test folder and running maven first time, before you run tests via IDE are needed steps. Without these steps, if you just in your IDE create test resources, then write test and run it via IDE only, you'll get an error. Running tests via mvn copies test resources into target/test-classes/teva/readme and they become accessible for a classloader.

You may ask, why do I need import more than one maven project in IDE and why so many complicated things? For me, one of the main motivation: keeping IDA-related files far from code. I first create a new project in my IDE. It is a fake project, that is just a holder of IDE-related files. Then, I import already existing maven projects. I force these imported projects to keep IDEA files in my original fake project only. As a result I don't see IDE-related files among the code. SVN should not see them (don't offer to configure svn/git to ignore such files, please). Also it is just very convenient.

Accessing post variables using Java Servlets

POST variables should be accessible via the request object: HttpRequest.getParameterMap(). The exception is if the form is sending multipart MIME data (the FORM has enctype="multipart/form-data"). In that case, you need to parse the byte stream with a MIME parser. You can write your own or use an existing one like the Apache Commons File Upload API.

Implement an input with a mask

I wrote a similar solution some time ago.
Of course it's just a PoC and can be improved further.

This solution covers the following features:

  • Seamless character input
  • Pattern customization
  • Live validation while you typing
  • Full date validation (including correct days in each month and a leap year consideration)
  • Descriptive errors, so the user will understand what is going on while he is unable to type a character
  • Fix cursor position and prevent selections
  • Show placeholder if the value is empty

_x000D_
_x000D_ 
const pattern = "__/__/____";_x000D_
const patternFreeChar = "_";_x000D_
const validDate = [_x000D_
  /^[0-3]$/,_x000D_
  /^(0[1-9]|[12]\d|3[01])$/,_x000D_
  /^(0[1-9]|[12]\d|3[01])[01]$/,_x000D_
  /^((0[1-9]|[12]\d|3[01])(0[13578]|1[02])|(0[1-9]|[12]\d|30)(0[469]|11)|(0[1-9]|[12]\d)02)$/,_x000D_
  /^((0[1-9]|[12]\d|3[01])(0[13578]|1[02])|(0[1-9]|[12]\d|30)(0[469]|11)|(0[1-9]|[12]\d)02)[12]$/,_x000D_
  /^((0[1-9]|[12]\d|3[01])(0[13578]|1[02])|(0[1-9]|[12]\d|30)(0[469]|11)|(0[1-9]|[12]\d)02)(19|20)/_x000D_
]_x000D_
_x000D_
/**_x000D_
 * Validate a date as your type._x000D_
 * @param {string} date The date in format DDMMYYYY as a string representation._x000D_
 * @throws {Error} When the date is invalid._x000D_
 */_x000D_
function validateStartTypingDate(date) {_x000D_
  if ( !date ) return "";_x000D_
  _x000D_
  date = date.substr(0, 8);_x000D_
  _x000D_
  if ( !/^\d+$/.test(date) )_x000D_
   throw new Error("Please type numbers only");_x000D_
  _x000D_
 if ( !validDate[Math.min(date.length-1,validDate.length-1)].test(date) ) {_x000D_
    let errMsg = "";_x000D_
    switch ( date.length ) {_x000D_
     case 1:_x000D_
       throw new Error("Day in month can start only with 0, 1, 2 or 3");_x000D_
        _x000D_
     case 2:_x000D_
       throw new Error("Day in month must be in a range between 01 and 31");_x000D_
        _x000D_
     case 3:_x000D_
       throw new Error("Month can start only with 0 or 1");_x000D_
        _x000D_
     case 4: {_x000D_
       const day = parseInt(date.substr(0,2));_x000D_
       const month = parseInt(date.substr(2,2));_x000D_
        const monthName = new Date(0,month-1).toLocaleString('en-us',{month:'long'});_x000D_
        _x000D_
        if ( month < 1 || month > 12 )_x000D_
         throw new Error("Month number must be in a range between 01 and 12");_x000D_
          _x000D_
        if ( day > 30 && [4,6,9,11].includes(month) )_x000D_
         throw new Error(`${monthName} have maximum 30 days`);_x000D_
          _x000D_
        if ( day > 29 && month === 2 )_x000D_
         throw new Error(`${monthName} have maximum 29 days`);_x000D_
        break; _x000D_
      }_x000D_
         _x000D_
      case 5:_x000D_
      case 6:_x000D_
       throw new Error("We support only years between 1900 and 2099, so the full year can start only with 19 or 20");_x000D_
    }_x000D_
  }_x000D_
  _x000D_
  if ( date.length === 8 ) {_x000D_
   const day = parseInt(date.substr(0,2));_x000D_
    const month = parseInt(date.substr(2,2));_x000D_
    const year = parseInt(date.substr(4,4));_x000D_
    const monthName = new Date(0,month-1).toLocaleString('en-us',{month:'long'});_x000D_
    if ( !isLeap(year) && month === 2 && day === 29 )_x000D_
      throw new Error(`The year you are trying to enter (${year}) is not a leap year. Thus, in this year, ${monthName} can have maximum 28 days`);_x000D_
  }_x000D_
  _x000D_
  return date;_x000D_
}_x000D_
_x000D_
/**_x000D_
 * Check whether the given year is a leap year._x000D_
 */_x000D_
function isLeap(year) {_x000D_
  return new Date(year, 1, 29).getDate() === 29;_x000D_
}_x000D_
_x000D_
/**_x000D_
 * Move cursor to the end of the provided input element._x000D_
 */_x000D_
function moveCursorToEnd(el) {_x000D_
 if (typeof el.selectionStart == "number") {_x000D_
  el.selectionStart = el.selectionEnd = el.value.length;_x000D_
 } else if (typeof el.createTextRange != "undefined") {_x000D_
  el.focus();_x000D_
  var range = el.createTextRange();_x000D_
  range.collapse(false);_x000D_
  range.select();_x000D_
 }_x000D_
}_x000D_
_x000D_
/**_x000D_
 * Move cursor to the end of the self input element._x000D_
 */_x000D_
function selfMoveCursorToEnd() {_x000D_
 return moveCursorToEnd(this);_x000D_
}_x000D_
_x000D_
const input = document.querySelector("input")_x000D_
_x000D_
input.addEventListener("keydown", function(event){_x000D_
 event.preventDefault();_x000D_
  document.getElementById("date-error-msg").innerText = "";_x000D_
  _x000D_
  // On digit pressed_x000D_
  let inputMemory = this.dataset.inputMemory || "";_x000D_
  _x000D_
  if ( event.key.length === 1 ) {_x000D_
    try {_x000D_
      inputMemory = validateStartTypingDate(inputMemory + event.key);_x000D_
    } catch (err) {_x000D_
      document.getElementById("date-error-msg").innerText = err.message;_x000D_
    }_x000D_
  }_x000D_
  _x000D_
  // On backspace pressed_x000D_
  if ( event.code === "Backspace" ) {_x000D_
   inputMemory = inputMemory.slice(0, -1);_x000D_
  }_x000D_
  _x000D_
  // Build an output using a pattern_x000D_
  if ( this.dataset.inputMemory !== inputMemory ) {_x000D_
   let output = pattern;_x000D_
   for ( let i=0, digit; i<inputMemory.length, digit=inputMemory[i]; i++ ) {_x000D_
     output = output.replace(patternFreeChar, digit);_x000D_
    }_x000D_
    this.dataset.inputMemory = inputMemory;_x000D_
    this.value = output;_x000D_
  }_x000D_
  _x000D_
  // Clean the value if the memory is empty_x000D_
  if ( inputMemory === "" ) {_x000D_
   this.value = "";_x000D_
  }_x000D_
}, false);_x000D_
_x000D_
input.addEventListener('select', selfMoveCursorToEnd, false);_x000D_
input.addEventListener('mousedown', selfMoveCursorToEnd, false);_x000D_
input.addEventListener('mouseup', selfMoveCursorToEnd, false);_x000D_
input.addEventListener('click', selfMoveCursorToEnd, false);
_x000D_ 
<input type="text" placeholder="DD/MM/YYYY" />_x000D_
<div id="date-error-msg"></div>
_x000D_
_x000D_
_x000D_

A link to jsfiddle: https://jsfiddle.net/d1xbpw8f/56/

Good luck!

Math functions in AngularJS bindings

You have to inject Math into your scope, if you need to use it as $scope know nothing about Math.

Simplest way, you can do

$scope.Math = window.Math;

in your controller. Angular way to do this correctly would be create a Math service, I guess.

How do I kill an Activity when the Back button is pressed?

 
public boolean onKeyDown(int keycode, KeyEvent event) {
    if (keycode == KeyEvent.KEYCODE_BACK) {
        moveTaskToBack(true);
    }
    return super.onKeyDown(keycode, event);
}

My app closed with above code.

How to use `subprocess` command with pipes

To use a pipe with the subprocess module, you have to pass shell=True.

However, this isn't really advisable for various reasons, not least of which is security. Instead, create the ps and grep processes separately, and pipe the output from one into the other, like so:

ps = subprocess.Popen(('ps', '-A'), stdout=subprocess.PIPE)
output = subprocess.check_output(('grep', 'process_name'), stdin=ps.stdout)
ps.wait()

In your particular case, however, the simple solution is to call subprocess.check_output(('ps', '-A')) and then str.find on the output.

get data from mysql database to use in javascript

Probably the easiest way to do it is to have a php file return JSON. So let's say you have a file query.php,

$result = mysql_query("SELECT field_name, field_value
                       FROM the_table");
$to_encode = array();
while($row = mysql_fetch_assoc($result)) {
  $to_encode[] = $row;
}
echo json_encode($to_encode);

If you're constrained to using document.write (as you note in the comments below) then give your fields an id attribute like so: <input type="text" id="field1" />. You can reference that field with this jQuery: $("#field1").val().

Here's a complete example with the HTML. If we're assuming your fields are called field1 and field2, then

<!DOCTYPE html>
<html>
  <head>
    <title>That's about it</title>
  </head>
  <body>
    <form>
      <input type="text" id="field1" />
      <input type="text" id="field2" />
    </form>
  </body>
  <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.5.1/jquery.min.js"></script>
  <script>
    $.getJSON('data.php', function(data) {
      $.each(data, function(fieldName, fieldValue) {
        $("#" + fieldName).val(fieldValue);
      });
    });
  </script>
</html>

That's insertion after the HTML has been constructed, which might be easiest. If you mean to populate data while you're dynamically constructing the HTML, then you'd still want the PHP file to return JSON, you would just add it directly into the value attribute.

Where is Python's sys.path initialized from?

Python really tries hard to intelligently set sys.path. How it is set can get really complicated. The following guide is a watered-down, somewhat-incomplete, somewhat-wrong, but hopefully-useful guide for the rank-and-file python programmer of what happens when python figures out what to use as the initial values of sys.path, sys.executable, sys.exec_prefix, and sys.prefix on a normal python installation.

First, python does its level best to figure out its actual physical location on the filesystem based on what the operating system tells it. If the OS just says "python" is running, it finds itself in $PATH. It resolves any symbolic links. Once it has done this, the path of the executable that it finds is used as the value for sys.executable, no ifs, ands, or buts.

Next, it determines the initial values for sys.exec_prefix and sys.prefix.

If there is a file called pyvenv.cfg in the same directory as sys.executable or one directory up, python looks at it. Different OSes do different things with this file.

One of the values in this config file that python looks for is the configuration option home = <DIRECTORY>. Python will use this directory instead of the directory containing sys.executable when it dynamically sets the initial value of sys.prefix later. If the applocal = true setting appears in the pyvenv.cfg file on Windows, but not the home = <DIRECTORY> setting, then sys.prefix will be set to the directory containing sys.executable.

Next, the PYTHONHOME environment variable is examined. On Linux and Mac, sys.prefix and sys.exec_prefix are set to the PYTHONHOME environment variable, if it exists, superseding any home = <DIRECTORY> setting in pyvenv.cfg. On Windows, sys.prefix and sys.exec_prefix is set to the PYTHONHOME environment variable, if it exists, unless a home = <DIRECTORY> setting is present in pyvenv.cfg, which is used instead.

Otherwise, these sys.prefix and sys.exec_prefix are found by walking backwards from the location of sys.executable, or the home directory given by pyvenv.cfg if any.

If the file lib/python<version>/dyn-load is found in that directory or any of its parent directories, that directory is set to be to be sys.exec_prefix on Linux or Mac. If the file lib/python<version>/os.py is is found in the directory or any of its subdirectories, that directory is set to be sys.prefix on Linux, Mac, and Windows, with sys.exec_prefix set to the same value as sys.prefix on Windows. This entire step is skipped on Windows if applocal = true is set. Either the directory of sys.executable is used or, if home is set in pyvenv.cfg, that is used instead for the initial value of sys.prefix.

If it can't find these "landmark" files or sys.prefix hasn't been found yet, then python sets sys.prefix to a "fallback" value. Linux and Mac, for example, use pre-compiled defaults as the values of sys.prefix and sys.exec_prefix. Windows waits until sys.path is fully figured out to set a fallback value for sys.prefix.

Then, (what you've all been waiting for,) python determines the initial values that are to be contained in sys.path.

  1. The directory of the script which python is executing is added to sys.path. On Windows, this is always the empty string, which tells python to use the full path where the script is located instead.
  2. The contents of PYTHONPATH environment variable, if set, is added to sys.path, unless you're on Windows and applocal is set to true in pyvenv.cfg.
  3. The zip file path, which is <prefix>/lib/python35.zip on Linux/Mac and os.path.join(os.dirname(sys.executable), "python.zip") on Windows, is added to sys.path.
  4. If on Windows and no applocal = true was set in pyvenv.cfg, then the contents of the subkeys of the registry key HK_CURRENT_USER\Software\Python\PythonCore\<DLLVersion>\PythonPath\ are added, if any.
  5. If on Windows and no applocal = true was set in pyvenv.cfg, and sys.prefix could not be found, then the core contents of the of the registry key HK_CURRENT_USER\Software\Python\PythonCore\<DLLVersion>\PythonPath\ is added, if it exists;
  6. If on Windows and no applocal = true was set in pyvenv.cfg, then the contents of the subkeys of the registry key HK_LOCAL_MACHINE\Software\Python\PythonCore\<DLLVersion>\PythonPath\ are added, if any.
  7. If on Windows and no applocal = true was set in pyvenv.cfg, and sys.prefix could not be found, then the core contents of the of the registry key HK_CURRENT_USER\Software\Python\PythonCore\<DLLVersion>\PythonPath\ is added, if it exists;
  8. If on Windows, and PYTHONPATH was not set, the prefix was not found, and no registry keys were present, then the relative compile-time value of PYTHONPATH is added; otherwise, this step is ignored.
  9. Paths in the compile-time macro PYTHONPATH are added relative to the dynamically-found sys.prefix.
  10. On Mac and Linux, the value of sys.exec_prefix is added. On Windows, the directory which was used (or would have been used) to search dynamically for sys.prefix is added.

At this stage on Windows, if no prefix was found, then python will try to determine it by searching all the directories in sys.path for the landmark files, as it tried to do with the directory of sys.executable previously, until it finds something. If it doesn't, sys.prefix is left blank.

Finally, after all this, Python loads the site module, which adds stuff yet further to sys.path:

It starts by constructing up to four directories from a head and a tail part. For the head part, it uses sys.prefix and sys.exec_prefix; empty heads are skipped. For the tail part, it uses the empty string and then lib/site-packages (on Windows) or lib/pythonX.Y/site-packages and then lib/site-python (on Unix and Macintosh). For each of the distinct head-tail combinations, it sees if it refers to an existing directory, and if so, adds it to sys.path and also inspects the newly added path for configuration files.

Determine the size of an InputStream

When explicitly dealing with a ByteArrayInputStream then contrary to some of the comments on this page you can use the .available() function to get the size. Just have to do it before you start reading from it.

From the JavaDocs:

Returns the number of remaining bytes that can be read (or skipped over) from this input stream. The value returned is count - pos, which is the number of bytes remaining to be read from the input buffer.

https://docs.oracle.com/javase/7/docs/api/java/io/ByteArrayInputStream.html#available()

The requested URL /about was not found on this server

The selected answer didn't solve this issue for me. So for those still scratching their head over this one, I found another solution!

In my Apache settings httpd.conf(you can find the conf file by running apachectl -V in your console), enabled the following module:

LoadModule rewrite_module modules/mod_rewrite.so

And now the site works as expected.

Android getResources().getDrawable() deprecated API 22

Try this:

public static List<ProductActivity> getCatalog(Resources res){
    if(catalog == null) {
        catalog.add(new Product("Dead or Alive", res
                .getDrawable(R.drawable.product_salmon),
                "Dead or Alive by Tom Clancy with Grant Blackwood", 29.99));
        catalog.add(new Product("Switch", res
                .getDrawable(R.drawable.switchbook),
                "Switch by Chip Heath and Dan Heath", 24.99));
        catalog.add(new Product("Watchmen", res
                .getDrawable(R.drawable.watchmen),
                "Watchmen by Alan Moore and Dave Gibbons", 14.99));
    }
}

LaTeX source code listing like in professional books

I wonder why nobody mentioned the Minted package. It has far better syntax highlighting than the LaTeX listing package. It uses Pygments.

$ pip install Pygments

Example in LaTeX:

\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[english]{babel}

\usepackage{minted}

\begin{document}
\begin{minted}{python}
import numpy as np

def incmatrix(genl1,genl2):
    m = len(genl1)
    n = len(genl2)
    M = None #to become the incidence matrix
    VT = np.zeros((n*m,1), int)  #dummy variable

    #compute the bitwise xor matrix
    M1 = bitxormatrix(genl1)
    M2 = np.triu(bitxormatrix(genl2),1) 

    for i in range(m-1):
        for j in range(i+1, m):
            [r,c] = np.where(M2 == M1[i,j])
            for k in range(len(r)):
                VT[(i)*n + r[k]] = 1;
                VT[(i)*n + c[k]] = 1;
                VT[(j)*n + r[k]] = 1;
                VT[(j)*n + c[k]] = 1;

                if M is None:
                    M = np.copy(VT)
                else:
                    M = np.concatenate((M, VT), 1)

                VT = np.zeros((n*m,1), int)

    return M
\end{minted}
\end{document}

Which results in:

enter image description here

You need to use the flag -shell-escape with the pdflatex command.

For more information: https://www.sharelatex.com/learn/Code_Highlighting_with_minted

How to disable <br> tags inside <div> by css?

You could alter your CSS to render them less obtrusively, e.g.

div p,
div br {
    display: inline;
}

http://jsfiddle.net/zG9Ax/

or - as my commenter points out:

div br {
    display: none;
}

but then to achieve the example of what you want, you'll need to trim the p down, so:

div br {
    display: none;
}
div p {
    padding: 0;
    margin: 0;
}

http://jsfiddle.net/zG9Ax/1

Maximum concurrent connections to MySQL

I can assure you that raw speed ultimately lies in the non-standard use of Indexes for blazing speed using large tables.

JSON, REST, SOAP, WSDL, and SOA: How do they all link together

WSDL: Stands for Web Service Description Language

In SOAP(simple object access protocol), when you use web service and add a web service to your project, your client application(s) doesn't know about web service Functions. Nowadays it's somehow old-fashion and for each kind of different client you have to implement different WSDL files. For example you cannot use same file for .Net and php client. The WSDL file has some descriptions about web service functions. The type of this file is XML. SOAP is an alternative for REST.

REST: Stands for Representational State Transfer

It is another kind of API service, it is really easy to use for clients. They do not need to have special file extension like WSDL files. The CRUD operation can be implemented by different HTTP Verbs(GET for Reading, POST for Creation, PUT or PATCH for Updating and DELETE for Deleting the desired document) , They are based on HTTP protocol and most of times the response is in JSON or XML format. On the other hand the client application have to exactly call the related HTTP Verb via exact parameters names and types. Due to not having special file for definition, like WSDL, it is a manually job using the endpoint. But it is not a big deal because now we have a lot of plugins for different IDEs to generating the client-side implementation.

SOA: Stands for Service Oriented Architecture

Includes all of the programming with web services concepts and architecture. Imagine that you want to implement a large-scale application. One practice can be having some different services, called micro-services and the whole application mechanism would be calling needed web service at the right time. Both REST and SOAP web services are kind of SOA.

JSON: Stands for javascript Object Notation

when you serialize an object for javascript the type of object format is JSON. imagine that you have the human class : 

class Human{
 string Name;
 string Family;
 int Age;
}

and you have some instances from this class :

Human h1 = new Human(){
  Name='Saman',
  Family='Gholami',
  Age=26
}

when you serialize the h1 object to JSON the result is :

  [h1:{Name:'saman',Family:'Gholami',Age:'26'}, ...]

javascript can evaluate this format by eval() function and make an associative array from this JSON string. This one is different concept in comparison to other concepts I described formerly.

Excel doesn't update value unless I hit Enter

Executive summary / TL;DR:
Try doing a find & replace of "=" with "=". Yes, replace the equals sign with itself. For my scenario, it forced everything to update.

Background:
I frequently make formulas across multiple columns then concatenate them together. After doing such, I'll copy & paste them as values to extract my created formula. After this process, they're typically stuck displaying a formula, and not displaying a value, unless I enter the cell and press Enter. Pressing F2 & Enter repeatedly is not fun.

Including external HTML file to another HTML file

You can use jquery load for that.

<script type="text/javascript">
$(document).ready(function(e) {
    $('#header').load('name.html',function(){alert('loaded')});
});
</script>

Don't forget to include jquery library befor above code.

When should I use a trailing slash in my URL?

That's not really a question of aesthetics, but indeed a technical difference. The directory thinking of it is totally correct and pretty much explaining everything. Let's work it out:

You are back in the stone age now or only serve static pages

You have a fixed directory structure on your web server and only static files like images, html and so on — no server side scripts or whatsoever.

A browser requests /index.htm, it exists and is delivered to the client. Later you have lots of - let's say - DVD movies reviewed and a html page for each of them in the /dvd/ directory. Now someone requests /dvd/adams_apples.htm and it is delivered because it is there.

At some day, someone just requests /dvd/ - which is a directory and the server is trying to figure out what to deliver. Besides access restrictions and so on there are two possibilities: Show the user the directory content (I bet you already have seen this somewhere) or show a default file (in Apache it is: DirectoryIndex: sets the file that Apache will serve if a directory is requested.)

So far so good, this is the expected case. It already shows the difference in handling, so let's get into it:

At 5:34am you made a mistake uploading your files

(Which is by the way completely understandable.) So, you did something entirely wrong and instead of uploading /dvd/the_big_lebowski.htm you uploaded that file as dvd (with no extension) to /.

Someone bookmarked your /dvd/ directory listing (of course you didn't want to create and always update that nifty index.htm) and is visiting your web-site. Directory content is delivered - all fine.

Someone heard of your list and is typing /dvd. And now it is screwed. Instead of your DVD directory listing the server finds a file with that name and is delivering your Big Lebowski file.

So, you delete that file and tell the guy to reload the page. Your server looks for the /dvd file, but it is gone. Most servers will then notice that there is a directory with that name and tell the client that what it was looking for is indeed somewhere else. The response will most likely be be:

Status Code:301 Moved Permanently with Location: http://[...]/dvd/

So, totally ignoring what you think about directories or files, the server only can handle such stuff and - unless told differently - decides for you about the meaning of "slash or not".

Finally after receiving this response, the client loads /dvd/ and everything is fine.

Is it fine? No.

"Just fine" is not good enough for you

You have some dynamic page where everything is passed to /index.php and gets processed. Everything worked quite good until now, but that entire thing starts to feel slower and you investigate.

Soon, you'll notice that /dvd/list is doing exactly the same: Redirecting to /dvd/list/ which is then internally translated into index.php?controller=dvd&action=list. One additional request - but even worse! customer/login redirects to customer/login/ which in turn redirects to the HTTPS URL of customer/login/. You end up having tons of unnecessary HTTP redirects (= additional requests) that make the user experience slower.

Most likely you have a default directory index here, too: index.php?controller=dvd with no action simply internally loads index.php?controller=dvd&action=list.

Summary:

  • If it ends with / it can never be a file. No server guessing.

  • Slash or no slash are entirely different meanings. There is a technical/resource difference between "slash or no slash", and you should be aware of it and use it accordingly. Just because the server most likely loads /dvd/index.htm - or loads the correct script stuff - when you say /dvd: It does it, but not because you made the right request. Which would have been /dvd/.

  • Omitting the slash even if you indeed mean the slashed version gives you an additional HTTP request penalty. Which is always bad (think of mobile latency) and has more weight than a "pretty URL" - especially since crawlers are not as dumb as SEOs believe or want you to believe ;)

Create unique constraint with null columns

Create two partial indexes:

CREATE UNIQUE INDEX favo_3col_uni_idx ON favorites (user_id, menu_id, recipe_id)
WHERE menu_id IS NOT NULL;

CREATE UNIQUE INDEX favo_2col_uni_idx ON favorites (user_id, recipe_id)
WHERE menu_id IS NULL;

This way, there can only be one combination of (user_id, recipe_id) where menu_id IS NULL, effectively implementing the desired constraint.

Possible drawbacks: you cannot have a foreign key referencing (user_id, menu_id, recipe_id), you cannot base CLUSTER on a partial index, and queries without a matching WHERE condition cannot use the partial index. (It seems unlikely you'd want a FK reference three columns wide - use the PK column instead).

If you need a complete index, you can alternatively drop the WHERE condition from favo_3col_uni_idx and your requirements are still enforced.
The index, now comprising the whole table, overlaps with the other one and gets bigger. Depending on typical queries and the percentage of NULL values, this may or may not be useful. In extreme situations it might even help to maintain all three indexes (the two partial ones and a total on top).

Aside: I advise not to use mixed case identifiers in PostgreSQL.

Position one element relative to another in CSS

position: absolute will position the element by coordinates, relative to the closest positioned ancestor, i.e. the closest parent which isn't position: static.

Have your four divs nested inside the target div, give the target div position: relative, and use position: absolute on the others.

Structure your HTML similar to this:

<div id="container">
  <div class="top left"></div>
  <div class="top right"></div>
  <div class="bottom left"></div>
  <div class="bottom right"></div>
</div>

And this CSS should work:

#container {
  position: relative;
}

#container > * {
  position: absolute;
}

.left {
  left: 0;
}

.right {
  right: 0;
}

.top {
  top: 0;
}

.bottom {
  bottom: 0;
}

...

Can I change the name of `nohup.out`?

my start.sh file:

#/bin/bash

nohup forever -c php artisan your:command >>storage/logs/yourcommand.log 2>&1 &

There is one important thing only. FIRST COMMAND MUST BE "nohup", second command must be "forever" and "-c" parameter is forever's param, "2>&1 &" area is for "nohup". After running this line then you can logout from your terminal, relogin and run "forever restartall" voilaa... You can restart and you can be sure that if script halts then forever will restart it.

I <3 forever

QED symbol in latex

I think you are looking for this:

\newcommand*{\QEDA}{\hfill\ensuremath{\blacksquare}}

Usage:

\begin{example}
  blah blah blah \QEDA
\end{example}

linux shell script: split string, put them in an array then loop through them

 
sentence="one;two;three"
a="${sentence};"
while [ -n "${a}" ]
do
    echo ${a%%;*}
    a=${a#*;}
done

Using true and false in C

I would go for 1. I haven't met incompatibility with it and is more natural. But, I think that it is a part of C++ not C standard. I think that with dirty hacking with defines or your third option - won't gain any performance, but only pain maintaining the code.

Make an html number input always display 2 decimal places

So if someone else stumbles upon this here is a JavaScript solution to this problem:

Step 1: Hook your HTML number input box to an onchange event

myHTMLNumberInput.onchange = setTwoNumberDecimal;

or in the html code if you so prefer

<input type="number" onchange="setTwoNumberDecimal" min="0" max="10" step="0.25" value="0.00" />

Step 2: Write the setTwoDecimalPlace method

function setTwoNumberDecimal(event) {
    this.value = parseFloat(this.value).toFixed(2);
}

By changing the '2' in toFixed you can get more or less decimal places if you so prefer.

'Connect-MsolService' is not recognized as the name of a cmdlet

Following worked for me:

  1. Uninstall the previously installed ‘Microsoft Online Service Sign-in Assistant’ and ‘Windows Azure Active Directory Module for Windows PowerShell’.
  2. Install 64-bit versions of ‘Microsoft Online Service Sign-in Assistant’ and ‘Windows Azure Active Directory Module for Windows PowerShell’. https://littletalk.wordpress.com/2013/09/23/install-and-configure-the-office-365-powershell-cmdlets/

If you get the following error In order to install Windows Azure Active Directory Module for Windows PowerShell, you must have Microsoft Online Services Sign-In Assistant version 7.0 or greater installed on this computer, then install the Microsoft Online Services Sign-In Assistant for IT Professionals BETA: http://www.microsoft.com/en-us/download/details.aspx?id=39267

  1. Copy the folders called MSOnline and MSOnline Extended from the source

C:\Windows\System32\WindowsPowerShell\v1.0\Modules\

to the folder

C:\Windows\SysWOW64\WindowsPowerShell\v1.0\Modules\

https://stackoverflow.com/a/16018733/5810078.

(But I have actually copied all the possible files from

C:\Windows\System32\WindowsPowerShell\v1.0\

to

C:\Windows\SysWOW64\WindowsPowerShell\v1.0\

(For copying you need to alter the security permissions of that folder))

How to show PIL images on the screen?

You can display an image in your own window using Tkinter, w/o depending on image viewers installed in your system:

import Tkinter as tk
from PIL import Image, ImageTk  # Place this at the end (to avoid any conflicts/errors)

window = tk.Tk()
#window.geometry("500x500") # (optional)    
imagefile = {path_to_your_image_file}
img = ImageTk.PhotoImage(Image.open(imagefile))
lbl = tk.Label(window, image = img).pack()
window.mainloop()

For Python 3, replace import Tkinter as tk with import tkinter as tk.

Excel VBA For Each Worksheet Loop

Try to slightly modify your code:

Sub forEachWs()
    Dim ws As Worksheet
    For Each ws In ActiveWorkbook.Worksheets
        Call resizingColumns(ws)
    Next
End Sub

Sub resizingColumns(ws As Worksheet)
    With ws
        .Range("A:A").ColumnWidth = 20.14
        .Range("B:B").ColumnWidth = 9.71
        .Range("C:C").ColumnWidth = 35.86
        .Range("D:D").ColumnWidth = 30.57
        .Range("E:E").ColumnWidth = 23.57
        .Range("F:F").ColumnWidth = 21.43
        .Range("G:G").ColumnWidth = 18.43
        .Range("H:H").ColumnWidth = 23.86
        .Range("i:I").ColumnWidth = 27.43
        .Range("J:J").ColumnWidth = 36.71
        .Range("K:K").ColumnWidth = 30.29
        .Range("L:L").ColumnWidth = 31.14
        .Range("M:M").ColumnWidth = 31
        .Range("N:N").ColumnWidth = 41.14
        .Range("O:O").ColumnWidth = 33.86
    End With
End Sub

Note, resizingColumns routine takes parametr - worksheet to which Ranges belongs.

Basically, when you're using Range("O:O") - code operats with range from ActiveSheet, that's why you should use With ws statement and then .Range("O:O").

And there is no need to use global variables (unless you are using them somewhere else)

How to save an image locally using Python whose URL address I already know?

 
import urllib
resource = urllib.urlopen("http://www.digimouth.com/news/media/2011/09/google-logo.jpg")
output = open("file01.jpg","wb")
output.write(resource.read())
output.close()

file01.jpg will contain your image.

How to restart Activity in Android

Just to combine Ralf and Ben's answers (including changes made in comments):

if (Build.VERSION.SDK_INT >= 11) {
    recreate();
} else {
    Intent intent = getIntent();
    intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
    finish();
    overridePendingTransition(0, 0);

    startActivity(intent);
    overridePendingTransition(0, 0);
}

How to get the current date and time

Just construct a new Date object without any arguments; this will assign the current date and time to the new object.

import java.util.Date;

Date d = new Date();

In the words of the Javadocs for the zero-argument constructor:

Allocates a Date object and initializes it so that it represents the time at which it was allocated, measured to the nearest millisecond.

Make sure you're using java.util.Date and not java.sql.Date -- the latter doesn't have a zero-arg constructor, and has somewhat different semantics that are the topic of an entirely different conversation. :)

Downloading MySQL dump from command line

If you have the database named archiedb, use this:

mysql -p <password for the database> --databases archiedb > /home/database_backup.sql

Assuming this is Linux, choose where the backup file will be saved.

Sql Server return the value of identity column after insert statement

Here goes a bunch of different ways to get the ID, including Scope_Identity:

https://stackoverflow.com/a/42655/1504882

Stopping fixed position scrolling at a certain point?

Here's a quick jQuery plugin I just wrote that can do what you require:

$.fn.followTo = function (pos) {
    var $this = this,
        $window = $(window);

    $window.scroll(function (e) {
        if ($window.scrollTop() > pos) {
            $this.css({
                position: 'absolute',
                top: pos
            });
        } else {
            $this.css({
                position: 'fixed',
                top: 0
            });
        }
    });
};

$('#yourDiv').followTo(250);

See working example →

GROUP_CONCAT ORDER BY

Try 

SELECT li.clientid, group_concat(li.views ORDER BY li.views) AS views,
       group_concat(li.percentage ORDER BY li.percentage) 
FROM table_views li 
GROUP BY client_id

http://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html#function%5Fgroup-concat

Display a decimal in scientific notation

This worked best for me:

import decimal
'%.2E' % decimal.Decimal('40800000000.00000000000000')
# 4.08E+10

C compiler for Windows?

GCC is ubiquitous. It is trusted and well understood by thousands of folks across dozens of communities.

Visual Studio is perhaps the best IDE ever developed. It has a great compiler underneath it. But it is strictly Windows-only.

If you're just playing, get GCC --it's free. If you're concerned about multiple platfroms, it's GCC. If you're talking serious Windows development, get Visual Studio.

How to copy a file to a remote server in Python using SCP or SSH?

Try this if you wan't to use SSL certificates:

import subprocess

try:
    # Set scp and ssh data.
    connUser = 'john'
    connHost = 'my.host.com'
    connPath = '/home/john/'
    connPrivateKey = '/home/user/myKey.pem'

    # Use scp to send file from local to host.
    scp = subprocess.Popen(['scp', '-i', connPrivateKey, 'myFile.txt', '{}@{}:{}'.format(connUser, connHost, connPath)])

except CalledProcessError:
    print('ERROR: Connection to host failed!')

How to split page into 4 equal parts?

Demo at http://jsfiddle.net/CRSVU/

_x000D_
_x000D_ 
html,
body {
  height: 100%;
  padding: 0;
  margin: 0;
}

div {
  width: 50%;
  height: 50%;
  float: left;
}

#div1 {
  background: #DDD;
}

#div2 {
  background: #AAA;
}

#div3 {
  background: #777;
}

#div4 {
  background: #444;
}
_x000D_ 
<div id="div1"></div>
<div id="div2"></div>
<div id="div3"></div>
<div id="div4"></div>
_x000D_
_x000D_
_x000D_

How to make sure you don't get WCF Faulted state exception?

This error can also be caused by having zero methods tagged with the OperationContract attribute. This was my problem when building a new service and testing it a long the way.

How do I correctly detect orientation change using Phonegap on iOS?

This is what I do:

_x000D_
_x000D_ 
function doOnOrientationChange() {_x000D_
    switch(window.orientation) {  _x000D_
      case -90: case 90:_x000D_
        alert('landscape');_x000D_
        break; _x000D_
      default:_x000D_
        alert('portrait');_x000D_
        break; _x000D_
    }_x000D_
}_x000D_
  _x000D_
window.addEventListener('orientationchange', doOnOrientationChange);_x000D_
  _x000D_
// Initial execution if needed_x000D_
doOnOrientationChange();
_x000D_
_x000D_
_x000D_

Update May 2019: window.orientation is a deprecated feature and not supported by most browsers according to MDN. The orientationchange event is associated with window.orientation and therefore should probably not be used.

The remote server returned an error: (403) Forbidden

Its a permissions error. Your VS probably runs using an elevated account or different user account than the user using the installed version.

It may be useful to check your IIS permissions and see what accounts have access to the resource you are accessing. Cross reference that with the account you use and the account the installed versions are using.

How To limit the number of characters in JTextField?

Just put this code in KeyTyped event:

    if ((jtextField.getText() + evt.getKeyChar()).length() > 20) {
        evt.consume();
    }

Where "20" is the maximum number of characters that you want.

Tomcat Servlet: Error 404 - The requested resource is not available

You have to user ../../projectName/Filename.jsp in your action attr. or href

../ = contains current folder simple(demo.project.filename.jsp)

Servlet can only be called with 1 slash forward to your project name..

What's wrong with foreign keys?

Verifying foreign key constraints takes some CPU time, so some folks omit foreign keys to get some extra performance.

Gather multiple sets of columns

This could be done using reshape. It is possible with dplyr though.

  colnames(df) <- gsub("\\.(.{2})$", "_\\1", colnames(df))
  colnames(df)[2] <- "Date"
  res <- reshape(df, idvar=c("id", "Date"), varying=3:8, direction="long", sep="_")
  row.names(res) <- 1:nrow(res)
  
   head(res)
  #  id       Date time       Q3.2       Q3.3
  #1  1 2009-01-01    1  1.3709584  0.4554501
  #2  2 2009-01-02    1 -0.5646982  0.7048373
  #3  3 2009-01-03    1  0.3631284  1.0351035
  #4  4 2009-01-04    1  0.6328626 -0.6089264
  #5  5 2009-01-05    1  0.4042683  0.5049551
  #6  6 2009-01-06    1 -0.1061245 -1.7170087

Or using dplyr

  library(tidyr)
  library(dplyr)
  colnames(df) <- gsub("\\.(.{2})$", "_\\1", colnames(df))

  df %>%
     gather(loop_number, "Q3", starts_with("Q3")) %>% 
     separate(loop_number,c("L1", "L2"), sep="_") %>% 
     spread(L1, Q3) %>%
     select(-L2) %>%
     head()
  #  id       time       Q3.2       Q3.3
  #1  1 2009-01-01  1.3709584  0.4554501
  #2  1 2009-01-01  1.3048697  0.2059986
  #3  1 2009-01-01 -0.3066386  0.3219253
  #4  2 2009-01-02 -0.5646982  0.7048373
  #5  2 2009-01-02  2.2866454 -0.3610573
  #6  2 2009-01-02 -1.7813084 -0.7838389

Update

With new version of tidyr, we can use pivot_longer to reshape multiple columns. (Using the changed column names from gsub above)

library(dplyr)
library(tidyr)
df %>% 
    pivot_longer(cols = starts_with("Q3"), 
          names_to = c(".value", "Q3"), names_sep = "_") %>% 
    select(-Q3)
# A tibble: 30 x 4
#      id time         Q3.2    Q3.3
#   <int> <date>      <dbl>   <dbl>
# 1     1 2009-01-01  0.974  1.47  
# 2     1 2009-01-01 -0.849 -0.513 
# 3     1 2009-01-01  0.894  0.0442
# 4     2 2009-01-02  2.04  -0.553 
# 5     2 2009-01-02  0.694  0.0972
# 6     2 2009-01-02 -1.11   1.85  
# 7     3 2009-01-03  0.413  0.733 
# 8     3 2009-01-03 -0.896 -0.271 
#9     3 2009-01-03  0.509 -0.0512
#10     4 2009-01-04  1.81   0.668 
# … with 20 more rows

NOTE: Values are different because there was no set seed in creating the input dataset

Replacing few values in a pandas dataframe column with another value

The easiest way is to use the replace method on the column. The arguments are a list of the things you want to replace (here ['ABC', 'AB']) and what you want to replace them with (the string 'A' in this case):

>>> df['BrandName'].replace(['ABC', 'AB'], 'A')
0    A
1    B
2    A
3    D
4    A

This creates a new Series of values so you need to assign this new column to the correct column name:

df['BrandName'] = df['BrandName'].replace(['ABC', 'AB'], 'A')

How do I unbind "hover" in jQuery?

Actually, the jQuery documentation has a more simple approach than the chained examples shown above (although they'll work just fine):

$("#myElement").unbind('mouseenter mouseleave');

As of jQuery 1.7, you are also able use $.on() and $.off() for event binding, so to unbind the hover event, you would use the simpler and tidier:

$('#myElement').off('hover');

The pseudo-event-name "hover" is used as a shorthand for "mouseenter mouseleave" but was handled differently in earlier jQuery versions; requiring you to expressly remove each of the literal event names. Using $.off() now allows you to drop both mouse events using the same shorthand.

Edit 2016:

Still a popular question so it's worth drawing attention to @Dennis98's point in the comments below that in jQuery 1.9+, the "hover" event was deprecated in favour of the standard "mouseenter mouseleave" calls. So your event binding declaration should now look like this:

$('#myElement').off('mouseenter mouseleave');

How can I bold the fonts of a specific row or cell in an Excel worksheet with C#?

How to Bold entire row 10 example: 

workSheet.Cells[10, 1].EntireRow.Font.Bold = true;

More formally:

Microsoft.Office.Interop.Excel.Range rng = workSheet.Cells[10, 1] as Xl.Range;
rng.EntireRow.Font.Bold = true;

How to Bold Specific Cell 'A10' for example:

workSheet.Cells[10, 1].Font.Bold = true;

Little more formal:

int row = 1;
int column = 1;  /// 1 = 'A' in Excel

Microsoft.Office.Interop.Excel.Range rng = workSheet.Cells[row, column] as Xl.Range;
rng.Font.Bold = true;

What does .class mean in Java?

Adding to the above answers:

Suppose you have a a class named "myPackage.MyClass". Assuming that is in classpath, the following statements are equivalent.

//checking class name using string comparison, only Runtime check possible
if(myInstance.getClass().getName().equals(Class.forName("myPackage.MyClass")).getName()){}

//checking actual Class object for equality, only Runtime check possible
if(myInstance.getClass().getName() == Class.forName("myPackage.MyClass"))){}

//checking actual Class object for equality, but compile time validation
//will ensure MyClass is in classpath. Hence this approach is better (according to fail-fast paradigm)
if(myInstance.getClass() == MyClass.class){}

Similarly, the following are also equivalent.

Class<?> myClassObject = MyClass.class; //compile time check

Class<?> myClassObject = Class.forname("myPackage.MyClass"); //only runtime check

If JVM loads a type, a class object representing that type will be present in JVM. we can get the metadata regarding the type from that class object which is used very much in reflection package. MyClass.class is a shorthand method which actually points to the Class object representing MyClass.

As an addendum, some information about Class<?> reference which will be useful to read along with this as most of the time, they are used together.

Class<?> reference type can hold any Class object which represents any type.

This works in a similar fashion if the Class<?> reference is in method argument as well.

Please note that the class "Class" does not have a public constructor. So you cannot instantiate "Class" instances with "new" operator.

How to debug in Django, the good way?

i highly suggest to use PDB.

import pdb
pdb.set_trace()

You can inspect all the variables values, step in to the function and much more. https://docs.python.org/2/library/pdb.html

for checking out the all kind of request,response and hits to database.i am using django-debug-toolbar https://github.com/django-debug-toolbar/django-debug-toolbar

Align <div> elements side by side

_x000D_
_x000D_ 
.section {
  display: flex;
}

.element-left {
  width: 94%;
}

.element-right {
  flex-grow: 1;
}
_x000D_ 
<div class="section">
  <div id="dB" class="element-left" }>
    <a href="http://notareallink.com" title="Download" id="buyButton">Download</a>
  </div>
  <div id="gB" class="element-right">
    <a href="#" title="Gallery" onclick="$j('#galleryDiv').toggle('slow');return false;" id="galleryButton">Gallery</a>
  </div>
</div>
_x000D_
_x000D_
_x000D_

or

_x000D_
_x000D_ 
.section {
  display: flex;
  flex-wrap: wrap;
}

.element-left {
  flex: 2;
}

.element-right {
  width: 100px;
}
_x000D_ 
<div class="section">
  <div id="dB" class="element-left" }>
    <a href="http://notareallink.com" title="Download" id="buyButton">Download</a>
  </div>
  <div id="gB" class="element-right">
    <a href="#" title="Gallery" onclick="$j('#galleryDiv').toggle('slow');return false;" id="galleryButton">Gallery</a>
  </div>
</div>
_x000D_
_x000D_
_x000D_

How to ignore the first line of data when processing CSV data?

use csv.DictReader instead of csv.Reader. If the fieldnames parameter is omitted, the values in the first row of the csvfile will be used as field names. you would then be able to access field values using row["1"] etc

How to check if element in groovy array/hash/collection/list?

For lists, use contains:

[1,2,3].contains(1) == true

MS SQL compare dates?

 
SELECT CASE WHEN CAST(date1 AS DATE) <= CAST(date2 AS DATE) ...

Should do what you need.

Test Case

WITH dates(date1, date2, date3, date4)
     AS (SELECT CAST('20101231 15:13:48.593' AS DATETIME),
                CAST('20101231 00:00:00.000' AS DATETIME),
                CAST('20101231 15:13:48.593' AS DATETIME),
                CAST('20101231 00:00:00.000' AS DATETIME))
SELECT CASE
         WHEN CAST(date1 AS DATE) <= CAST(date2 AS DATE) THEN 'Y'
         ELSE 'N'
       END AS COMPARISON_WITH_CAST,
       CASE
         WHEN date3 <= date4 THEN 'Y'
         ELSE 'N'
       END AS COMPARISON_WITHOUT_CAST
FROM   dates

Returns

COMPARISON_WITH_CAST   |  COMPARISON_WITHOUT_CAST
Y                         N

How to remove duplicate white spaces in string using Java?

This can be possible in three steps:

  1. Convert the string in to character array (ToCharArray)
  2. Apply for loop on charater array
  3. Then apply string replace function (Replace ("sting you want to replace"," original string"));

Get DateTime.Now with milliseconds precision

This should work:

DateTime.Now.ToString("hh.mm.ss.ffffff");

If you don't need it to be displayed and just need to know the time difference, well don't convert it to a String. Just leave it as, DateTime.Now();

And use TimeSpan to know the difference between time intervals:

Example

DateTime start;
TimeSpan time;

start = DateTime.Now;

//Do something here

time = DateTime.Now - start;
label1.Text = String.Format("{0}.{1}", time.Seconds, time.Milliseconds.ToString().PadLeft(3, '0'));

How do I dispatch_sync, dispatch_async, dispatch_after, etc in Swift 3, Swift 4, and beyond?

This one is good example for Swift 4 about async:

DispatchQueue.global(qos: .background).async {
    // Background Thread
    DispatchQueue.main.async {
        // Run UI Updates or call completion block
    }
}

Why does npm install say I have unmet dependencies?

Take care about your angular version, if you work under angular 2.x.x so maybe you need to upgrade to angular 4.x.x

Some dependencies needs angular 4

Here is a tutorial for how to install angular 4 or update your project.

How to run Rake tasks from within Rake tasks?

I would suggest not to create general debug and release tasks if the project is really something that gets compiled and so results in files. You should go with file-tasks which is quite doable in your example, as you state, that your output goes into different directories. Say your project just compiles a test.c file to out/debug/test.out and out/release/test.out with gcc you could setup your project like this:

WAYS = ['debug', 'release']
FLAGS = {}
FLAGS['debug'] = '-g'
FLAGS['release'] = '-O'
def out_dir(way)
  File.join('out', way)
end
def out_file(way)
  File.join(out_dir(way), 'test.out')
end
WAYS.each do |way|
  desc "create output directory for #{way}"
  directory out_dir(way)

  desc "build in the #{way}-way"
  file out_file(way) => [out_dir(way), 'test.c'] do |t|
    sh "gcc #{FLAGS[way]} -c test.c -o #{t.name}"
  end
end
desc 'build all ways'
task :all => WAYS.map{|way|out_file(way)}

task :default => [:all]

This setup can be used like:

rake all # (builds debug and release)
rake debug # (builds only debug)
rake release # (builds only release)

This does a little more as asked for, but shows my points:

  1. output directories are created, as necessary.
  2. the files are only recompiled if needed (this example is only correct for the simplest of test.c files).
  3. you have all tasks readily at hand if you want to trigger the release build or the debug build.
  4. this example includes a way to also define small differences between debug and release-builds.
  5. no need to reenable a build-task that is parametrized with a global variable, because now the different builds have different tasks. the codereuse of the build-task is done by reusing the code to define the build-tasks. see how the loop does not execute the same task twice, but instead created tasks, that can later be triggered (either by the all-task or be choosing one of them on the rake commandline).

Determining complexity for recursive functions (Big O notation)

We can prove it mathematically which is something I was missing in the above answers.

It can dramatically help you understand how to calculate any method. I recommend reading it from top to bottom to fully understand how to do it:

  1. T(n) = T(n-1) + 1 It means that the time it takes for the method to finish is equal to the same method but with n-1 which is T(n-1) and we now add + 1 because it's the time it takes for the general operations to be completed (except T(n-1)). Now, we are going to find T(n-1) as follow: T(n-1) = T(n-1-1) + 1. It looks like we can now form a function that can give us some sort of repetition so we can fully understand. We will place the right side of T(n-1) = ... instead of T(n-1) inside the method T(n) = ... which will give us: T(n) = T(n-1-1) + 1 + 1 which is T(n) = T(n-2) + 2 or in other words we need to find our missing k: T(n) = T(n-k) + k. The next step is to take n-k and claim that n-k = 1 because at the end of the recursion it will take exactly O(1) when n<=0. From this simple equation we now know that k = n - 1. Let's place k in our final method: T(n) = T(n-k) + k which will give us: T(n) = 1 + n - 1 which is exactly n or O(n).
  2. Is the same as 1. You can test it your self and see that you get O(n).
  3. T(n) = T(n/5) + 1 as before, the time for this method to finish equals to the time the same method but with n/5 which is why it is bounded to T(n/5). Let's find T(n/5) like in 1: T(n/5) = T(n/5/5) + 1 which is T(n/5) = T(n/5^2) + 1. Let's place T(n/5) inside T(n) for the final calculation: T(n) = T(n/5^k) + k. Again as before, n/5^k = 1 which is n = 5^k which is exactly as asking what in power of 5, will give us n, the answer is log5n = k (log of base 5). Let's place our findings in T(n) = T(n/5^k) + k as follow: T(n) = 1 + logn which is O(logn)
  4. T(n) = 2T(n-1) + 1 what we have here is basically the same as before but this time we are invoking the method recursively 2 times thus we multiple it by 2. Let's find T(n-1) = 2T(n-1-1) + 1 which is T(n-1) = 2T(n-2) + 1. Our next place as before, let's place our finding: T(n) = 2(2T(n-2)) + 1 + 1 which is T(n) = 2^2T(n-2) + 2 that gives us T(n) = 2^kT(n-k) + k. Let's find k by claiming that n-k = 1 which is k = n - 1. Let's place k as follow: T(n) = 2^(n-1) + n - 1 which is roughly O(2^n)
  5. T(n) = T(n-5) + n + 1 It's almost the same as 4 but now we add n because we have one for loop. Let's find T(n-5) = T(n-5-5) + n + 1 which is T(n-5) = T(n - 2*5) + n + 1. Let's place it: T(n) = T(n-2*5) + n + n + 1 + 1) which is T(n) = T(n-2*5) + 2n + 2) and for the k: T(n) = T(n-k*5) + kn + k) again: n-5k = 1 which is n = 5k + 1 that is roughly n = k. This will give us: T(n) = T(0) + n^2 + n which is roughly O(n^2).

I now recommend reading the rest of the answers which now, will give you a better perspective. Good luck winning those big O's :)

How to change a dataframe column from String type to Double type in PySpark?

Preserve the name of the column and avoid extra column addition by using the same name as input column:

changedTypedf = joindf.withColumn("show", joindf["show"].cast(DoubleType()))

How does the "this" keyword work?

Whould this help? (Most confusion of 'this' in javascript is coming from the fact that it generally is not linked to your object, but to the current executing scope -- that might not be exactly how it works but is always feels like that to me -- see the article for a complete explanation)

Android ListView with onClick items

I was able to go around the whole thing by replacing the context reference from this or Context.this to getapplicationcontext.

How to reset index in a pandas dataframe?

DataFrame.reset_index is what you're looking for. If you don't want it saved as a column, then do:

df = df.reset_index(drop=True)

If you don't want to reassign:

df.reset_index(drop=True, inplace=True)

Present and dismiss modal view controller

The easiest way i tired in xcode 4.52 was to create an additional view and connect them by using segue modal(control drag the button from view one to the second view, chose Modal). Then drag in a button to second view or the modal view that you created. Control and drag this button to the header file and use action connection. This will create an IBaction in your controller.m file. Find your button action type in the code.

[self dismissViewControllerAnimated:YES completion:nil];

Call to a member function on a non-object

Either $objPage is not an instance variable OR your are overwriting $objPage with something that is not an instance of class PageAttributes.

Show "loading" animation on button click

If you are using ajax then (making it as simple as possible)

  1. Add your loading gif image to html and make it hidden (using style in html itself now, you can add it to separate CSS):

    <img src="path\to\loading\gif" id="img" style="display:none"/ >

  2. Show the image when button is clicked and hide it again on success function

    $('#buttonID').click(function(){
  $('#img').show(); //<----here
  $.ajax({
    ....
   success:function(result){
       $('#img').hide();  //<--- hide again
   }
}

Make sure you hide the image on ajax error callbacks too to make sure the gif hides even if the ajax fails.