Programs & Examples On #Machine translation

What is so bad about singletons?

Some coding snobs look down on them as just a glorified global. In the same way that many people hate the goto statement there are others that hate the idea of ever using a global. I have seen several developers go to extraordinary lengths to avoid a global because they considered using one as an admission of failure. Strange but true.

In practice the Singleton pattern is just a programming technique that is a useful part of your toolkit of concepts. From time to time you might find it is the ideal solution and so use it. But using it just so you can boast about using a design pattern is just as stupid as refusing to ever use it because it is just a global.

SQL "IF", "BEGIN", "END", "END IF"?

If this is MS Sql Server then what you have should work fine... In fact, technically, you don;t need the Begin & End at all, snce there's only one statement in the begin-End Block... (I assume @Classes is a table variable ?)

If @Term = 3
   INSERT INTO @Classes
    SELECT                  XXXXXX  
     FROM XXXX blah blah blah
-- -----------------------------

 -- This next should always run, if the first code did not throw an exception... 
 INSERT INTO @Classes    
 SELECT XXXXXXXX        
 FROM XXXXXX (more code)

How to set null to a GUID property

Is there a way to set my property as null or string.empty in order to restablish the field in the database as null.

No. Because it's non-nullable. If you want it to be nullable, you have to use Nullable<Guid> - if you didn't, there'd be no point in having Nullable<T> to start with. You've got a fundamental issue here - which you actually know, given your first paragraph. You've said, "I know if I want to achieve A, I must do B - but I want to achieve A without doing B." That's impossible by definition.

The closest you can get is to use one specific GUID to stand in for a null value - Guid.Empty (also available as default(Guid) where appropriate, e.g. for the default value of an optional parameter) being the obvious candidate, but one you've rejected for unspecified reasons.

iOS app 'The application could not be verified' only on one device

I had something similar happen to me just recently. I updated my iPhone to 8.1.3, and started getting the 'application could not be verified' error message from Xcode on an app that installed just fine on the same iOS device from the same Mac just a few days ago.

I deleted the app from the device, restarted Xcode, and the app subsequently installed on the device just fine without any error message. Not sure if deleting the app was the fix, or the problem was due to "the phase of the moon".

jQuery .val() vs .attr("value")

If you get the same value for both property and attribute, but still sees it different on the HTML try this to get the HTML one:

$('#inputID').context.defaultValue;

numpy matrix vector multiplication

Simplest solution

Use numpy.dot or a.dot(b). See the documentation here.

>>> a = np.array([[ 5, 1 ,3], 
                  [ 1, 1 ,1], 
                  [ 1, 2 ,1]])
>>> b = np.array([1, 2, 3])
>>> print a.dot(b)
array([16, 6, 8])

This occurs because numpy arrays are not matrices, and the standard operations *, +, -, / work element-wise on arrays. Instead, you could try using numpy.matrix, and * will be treated like matrix multiplication.


Other Solutions

Also know there are other options:

  • As noted below, if using python3.5+ the @ operator works as you'd expect:

    >>> print(a @ b)
    array([16, 6, 8])
    
  • If you want overkill, you can use numpy.einsum. The documentation will give you a flavor for how it works, but honestly, I didn't fully understand how to use it until reading this answer and just playing around with it on my own.

    >>> np.einsum('ji,i->j', a, b)
    array([16, 6, 8])
    
  • As of mid 2016 (numpy 1.10.1), you can try the experimental numpy.matmul, which works like numpy.dot with two major exceptions: no scalar multiplication but it works with stacks of matrices.

    >>> np.matmul(a, b)
    array([16, 6, 8])
    
  • numpy.inner functions the same way as numpy.dot for matrix-vector multiplication but behaves differently for matrix-matrix and tensor multiplication (see Wikipedia regarding the differences between the inner product and dot product in general or see this SO answer regarding numpy's implementations).

    >>> np.inner(a, b)
    array([16, 6, 8])
    
    # Beware using for matrix-matrix multiplication though!
    >>> b = a.T
    >>> np.dot(a, b)
    array([[35,  9, 10],
           [ 9,  3,  4],
           [10,  4,  6]])
    >>> np.inner(a, b) 
    array([[29, 12, 19],
           [ 7,  4,  5],
           [ 8,  5,  6]])
    

Rarer options for edge cases

  • If you have tensors (arrays of dimension greater than or equal to one), you can use numpy.tensordot with the optional argument axes=1:

    >>> np.tensordot(a, b, axes=1)
    array([16,  6,  8])
    
  • Don't use numpy.vdot if you have a matrix of complex numbers, as the matrix will be flattened to a 1D array, then it will try to find the complex conjugate dot product between your flattened matrix and vector (which will fail due to a size mismatch n*m vs n).

What's the best practice using a settings file in Python?

The sample config you provided is actually valid YAML. In fact, YAML meets all of your demands, is implemented in a large number of languages, and is extremely human friendly. I would highly recommend you use it. The PyYAML project provides a nice python module, that implements YAML.

To use the yaml module is extremely simple:

import yaml
config = yaml.safe_load(open("path/to/config.yml"))

How do I dynamically change the content in an iframe using jquery?

var handle = setInterval(changeIframe, 30000);
var sites = ["google.com", "yahoo.com"];
var index = 0;

function changeIframe() {
  $('#frame')[0].src = sites[index++];
  index = index >= sites.length ? 0 : index;
}

MySQL equivalent of DECODE function in Oracle

You can use a CASE statement...however why don't you just create a table with an integer for ages between 0 and 150, a varchar for the written out age and then you can just join on that

Why does ++[[]][+[]]+[+[]] return the string "10"?

Step by steps of that, + turn value to a number and if you add to an empty array +[]...as it's empty and is equal to 0, it will

So from there, now look into your code, it's ++[[]][+[]]+[+[]]...

And there is plus between them ++[[]][+[]] + [+[]]

So these [+[]] will return [0] as they have an empty array which gets converted to 0 inside the other array...

So as imagine, the first value is a 2-dimensional array with one array inside... so [[]][+[]] will be equal to [[]][0] which will return []...

And at the end ++ convert it and increase it to 1...

So you can imagine, 1 + "0" will be "10"...

Why does return the string “10”?

How to trace the path in a Breadth-First Search?

I liked qiao's first answer very much! The only thing missing here is to mark the vertexes as visited.

Why we need to do it?
Lets imagine that there is another node number 13 connected from node 11. Now our goal is to find node 13.
After a little bit of a run the queue will look like this:

[[1, 2, 6], [1, 3, 10], [1, 4, 7], [1, 4, 8], [1, 2, 5, 9], [1, 2, 5, 10]]

Note that there are TWO paths with node number 10 at the end.
Which means that the paths from node number 10 will be checked twice. In this case it doesn't look so bad because node number 10 doesn't have any children.. But it could be really bad (even here we will check that node twice for no reason..)
Node number 13 isn't in those paths so the program won't return before reaching to the second path with node number 10 at the end..And we will recheck it..

All we are missing is a set to mark the visited nodes and not to check them again..
This is qiao's code after the modification:

graph = {
    1: [2, 3, 4],
    2: [5, 6],
    3: [10],
    4: [7, 8],
    5: [9, 10],
    7: [11, 12],
    11: [13]
}


def bfs(graph_to_search, start, end):
    queue = [[start]]
    visited = set()

    while queue:
        # Gets the first path in the queue
        path = queue.pop(0)

        # Gets the last node in the path
        vertex = path[-1]

        # Checks if we got to the end
        if vertex == end:
            return path
        # We check if the current node is already in the visited nodes set in order not to recheck it
        elif vertex not in visited:
            # enumerate all adjacent nodes, construct a new path and push it into the queue
            for current_neighbour in graph_to_search.get(vertex, []):
                new_path = list(path)
                new_path.append(current_neighbour)
                queue.append(new_path)

            # Mark the vertex as visited
            visited.add(vertex)


print bfs(graph, 1, 13)

The output of the program will be:

[1, 4, 7, 11, 13]

Without the unneccecery rechecks..

How to unmount, unrender or remove a component, from itself in a React/Redux/Typescript notification message

This isn't appropriate in all situations but you can conditionally return false inside the component itself if a certain criteria is or isn't met.

It doesn't unmount the component, but it removes all rendered content. This would only be bad, in my mind, if you have event listeners in the component that should be removed when the component is no longer needed.

import React, { Component } from 'react';

export default class MyComponent extends Component {
    constructor(props) {
        super(props);

        this.state = {
            hideComponent: false
        }
    }

    closeThis = () => {
        this.setState(prevState => ({
            hideComponent: !prevState.hideComponent
        })
    });

    render() {
        if (this.state.hideComponent === true) {return false;}

        return (
            <div className={`content`} onClick={() => this.closeThis}>
                YOUR CODE HERE
            </div>
        );
    }
}

How to check the version of scipy

From the python command prompt:

import scipy
print scipy.__version__

In python 3 you'll need to change it to:

print (scipy.__version__)

Pandas create empty DataFrame with only column names

Creating colnames with iterating

df = pd.DataFrame(columns=['colname_' + str(i) for i in range(5)])
print(df)

# Empty DataFrame
# Columns: [colname_0, colname_1, colname_2, colname_3, colname_4]
# Index: []

to_html() operations

print(df.to_html())

# <table border="1" class="dataframe">
#   <thead>
#     <tr style="text-align: right;">
#       <th></th>
#       <th>colname_0</th>
#       <th>colname_1</th>
#       <th>colname_2</th>
#       <th>colname_3</th>
#       <th>colname_4</th>
#     </tr>
#   </thead>
#   <tbody>
#   </tbody>
# </table>

this seems working

print(type(df.to_html()))
# <class 'str'>

The problem is caused by

when you create df like this

df = pd.DataFrame(columns=COLUMN_NAMES)

it has 0 rows × n columns, you need to create at least one row index by

df = pd.DataFrame(columns=COLUMN_NAMES, index=[0])

now it has 1 rows × n columns. You are be able to add data. Otherwise its df that only consist colnames object(like a string list).

Convert number to month name in PHP

You can do it in just one line:

DateTime::createFromFormat('!m', $salary->month)->format('F'); //April

HTML tag inside JavaScript

here's how to incorporate variables and html tags in document.write also note how you can simply add text between the quotes

document.write("<h1>System Paltform: ", navigator.platform, "</h1>");

How to list all functions in a Python module?

import types
import yourmodule

print([getattr(yourmodule, a) for a in dir(yourmodule)
  if isinstance(getattr(yourmodule, a), types.FunctionType)])

How to get the part of a file after the first line that matches a regular expression?

These will print all lines from the last found line "TERMINATE" till end of file:

LINE_NUMBER=`grep -o -n TERMINATE $OSCAM_LOG|tail -n 1|sed "s/:/ \\'/g"|awk -F" " '{print $1}'`
tail -n +$LINE_NUMBER $YOUR_FILE_NAME

Failed to install Python Cryptography package with PIP and setup.py

Those two commands fixed it for me:

brew install openssl
brew link openssl --force

Source: https://github.com/phusion/passenger/issues/1630#issuecomment-147527656

How to copy a char array in C?

You cannot assign arrays to copy them. How you can copy the contents of one into another depends on multiple factors:

For char arrays, if you know the source array is null terminated and destination array is large enough for the string in the source array, including the null terminator, use strcpy():

#include <string.h>

char array1[18] = "abcdefg";
char array2[18];

...

strcpy(array2, array1);

If you do not know if the destination array is large enough, but the source is a C string, and you want the destination to be a proper C string, use snprinf():

#include <stdio.h>

char array1[] = "a longer string that might not fit";
char array2[18];

...

snprintf(array2, sizeof array2, "%s", array1);

If the source array is not necessarily null terminated, but you know both arrays have the same size, you can use memcpy:

#include <string.h>

char array1[28] = "a non null terminated string";
char array2[28];

...

memcpy(array2, array1, sizeof array2);

Can you install and run apps built on the .NET framework on a Mac?

  • .NET Core will install and run on macOS - and just about any other desktop OS.
    IDEs are available for the mac, including:

  • Mono is a good option that I've used in the past. But with Core 3.0 out now, I would go that route.

python - find index position in list based of partial string

Your idea to use enumerate() was correct.

indices = []
for i, elem in enumerate(mylist):
    if 'aa' in elem:
        indices.append(i)

Alternatively, as a list comprehension:

indices = [i for i, elem in enumerate(mylist) if 'aa' in elem]

PHP expects T_PAAMAYIM_NEKUDOTAYIM?

From Wikipedia:

In PHP, the scope resolution operator is also called Paamayim Nekudotayim (Hebrew: ?????? ?????????), which means “double colon” in Hebrew.

The name "Paamayim Nekudotayim" was introduced in the Israeli-developed Zend Engine 0.5 used in PHP 3. Although it has been confusing to many developers who do not speak Hebrew, it is still being used in PHP 5, as in this sample error message:

$ php -r :: Parse error: syntax error, unexpected T_PAAMAYIM_NEKUDOTAYIM

As of PHP 5.4, error messages concerning the scope resolution operator still include this name, but have clarified its meaning somewhat:

$ php -r :: Parse error: syntax error, unexpected '::' (T_PAAMAYIM_NEKUDOTAYIM)

From the official PHP documentation:

The Scope Resolution Operator (also called Paamayim Nekudotayim) or in simpler terms, the double colon, is a token that allows access to static, constant, and overridden properties or methods of a class.

When referencing these items from outside the class definition, use the name of the class.

As of PHP 5.3.0, it's possible to reference the class using a variable. The variable's value can not be a keyword (e.g. self, parent and static).

Paamayim Nekudotayim would, at first, seem like a strange choice for naming a double-colon. However, while writing the Zend Engine 0.5 (which powers PHP 3), that's what the Zend team decided to call it. It actually does mean double-colon - in Hebrew!

How to line-break from css, without using <br />?

There are several options for defining the handling of white spaces and line breaks. If one can put the content in e.g. a <p> tag it is pretty easy to get whatever one wants.

For preserving line breaks but not white spaces use pre-line (not pre) like in:

<style>
 p {
     white-space: pre-line; /* collapse WS, preserve LB */
   }
</style>

<p>hello
How are you</p>

If another behavior is wanted choose among one of these (WS=WhiteSpace, LB=LineBreak):

     white-space: normal;   /* collapse WS, wrap as necessary, collapse LB */
     white-space: nowrap;   /* collapse WS, no wrapping,       collapse LB */
     white-space: pre;      /* preserve WS, no wrapping,       preserve LB */
     white-space: pre-wrap; /* preserve WS, wrap as necessary, preserve LB */
     white-space: inherit;  /* all as parent element */

SOURCE: W3 Schools

Spring: how do I inject an HttpServletRequest into a request-scoped bean?

Request-scoped beans can be autowired with the request object.

private @Autowired HttpServletRequest request;

What exactly is the 'react-scripts start' command?

As Sagiv b.g. pointed out, the npm start command is a shortcut for npm run start. I just wanted to add a real-life example to clarify it a bit more.

The setup below comes from the create-react-app github repo. The package.json defines a bunch of scripts which define the actual flow.

"scripts": {
  "start": "npm-run-all -p watch-css start-js",
  "build": "npm run build-css && react-scripts build",
  "watch-css": "npm run build-css && node-sass-chokidar --include-path ./src --include-path ./node_modules src/ -o src/ --watch --recursive",
  "build-css": "node-sass-chokidar --include-path ./src --include-path ./node_modules src/ -o src/",
  "start-js": "react-scripts start"
},

For clarity, I added a diagram. enter image description here

The blue boxes are references to scripts, all of which you could executed directly with an npm run <script-name> command. But as you can see, actually there are only 2 practical flows:

  • npm run start
  • npm run build

The grey boxes are commands which can be executed from the command line.

So, for instance, if you run npm start (or npm run start) that actually translate to the npm-run-all -p watch-css start-js command, which is executed from the commandline.

In my case, I have this special npm-run-all command, which is a popular plugin that searches for scripts that start with "build:", and executes all of those. I actually don't have any that match that pattern. But it can also be used to run multiple commands in parallel, which it does here, using the -p <command1> <command2> switch. So, here it executes 2 scripts, i.e. watch-css and start-js. (Those last mentioned scripts are watchers which monitor file changes, and will only finish when killed.)

  • The watch-css makes sure that the *.scss files are translated to *.cssfiles, and looks for future updates.

  • The start-js points to the react-scripts start which hosts the website in a development mode.

In conclusion, the npm start command is configurable. If you want to know what it does, then you have to check the package.json file. (and you may want to make a little diagram when things get complicated).

CASE statement in SQLite query

Also, you do not have to use nested CASEs. You can use several WHEN-THEN lines and the ELSE line is also optional eventhough I recomend it

CASE 
   WHEN [condition.1] THEN [expression.1]
   WHEN [condition.2] THEN [expression.2]
   ...
   WHEN [condition.n] THEN [expression.n]
   ELSE [expression] 
END

Can I get a patch-compatible output from git-diff?

A useful trick to avoid creating temporary patch files:

git diff | patch -p1 -d [dst-dir]

What is the fastest way to send 100,000 HTTP requests in Python?

Threads are absolutely not the answer here. They will provide both process and kernel bottlenecks, as well as throughput limits that are not acceptable if the overall goal is "the fastest way".

A little bit of twisted and its asynchronous HTTP client would give you much better results.

converting json to string in python

json.dumps() is much more than just making a string out of a Python object, it would always produce a valid JSON string (assuming everything inside the object is serializable) following the Type Conversion Table.

For instance, if one of the values is None, the str() would produce an invalid JSON which cannot be loaded:

>>> data = {'jsonKey': None}
>>> str(data)
"{'jsonKey': None}"
>>> json.loads(str(data))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/json/__init__.py", line 338, in loads
    return _default_decoder.decode(s)
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/json/decoder.py", line 366, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/json/decoder.py", line 382, in raw_decode
    obj, end = self.scan_once(s, idx)
ValueError: Expecting property name: line 1 column 2 (char 1)

But the dumps() would convert None into null making a valid JSON string that can be loaded:

>>> import json
>>> data = {'jsonKey': None}
>>> json.dumps(data)
'{"jsonKey": null}'
>>> json.loads(json.dumps(data))
{u'jsonKey': None}

How to align checkboxes and their labels consistently cross-browsers

For consistency with form fields across browsers we use : box-sizing: border-box

button, checkbox, input, radio, textarea, submit, reset, search, any-form-field {
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
    box-sizing: border-box;
}

C# List<> Sort by x then y

The trick is to implement a stable sort. I've created a Widget class that can contain your test data:

public class Widget : IComparable
{
    int x;
    int y;
    public int X
    {
        get { return x; }
        set { x = value; }
    }

    public int Y
    {
        get { return y; }
        set { y = value; }
    }

    public Widget(int argx, int argy)
    {
        x = argx;
        y = argy;
    }

    public int CompareTo(object obj)
    {
        int result = 1;
        if (obj != null && obj is Widget)
        {
            Widget w = obj as Widget;
            result = this.X.CompareTo(w.X);
        }
        return result;
    }

    static public int Compare(Widget x, Widget y)
    {
        int result = 1;
        if (x != null && y != null)                
        {                
            result = x.CompareTo(y);
        }
        return result;
    }
}

I implemented IComparable, so it can be unstably sorted by List.Sort().

However, I also implemented the static method Compare, which can be passed as a delegate to a search method.

I borrowed this insertion sort method from C# 411:

 public static void InsertionSort<T>(IList<T> list, Comparison<T> comparison)
        {           
            int count = list.Count;
            for (int j = 1; j < count; j++)
            {
                T key = list[j];

                int i = j - 1;
                for (; i >= 0 && comparison(list[i], key) > 0; i--)
                {
                    list[i + 1] = list[i];
                }
                list[i + 1] = key;
            }
    }

You would put this in the sort helpers class that you mentioned in your question.

Now, to use it:

    static void Main(string[] args)
    {
        List<Widget> widgets = new List<Widget>();

        widgets.Add(new Widget(0, 1));
        widgets.Add(new Widget(1, 1));
        widgets.Add(new Widget(0, 2));
        widgets.Add(new Widget(1, 2));

        InsertionSort<Widget>(widgets, Widget.Compare);

        foreach (Widget w in widgets)
        {
            Console.WriteLine(w.X + ":" + w.Y);
        }
    }

And it outputs:

0:1
0:2
1:1
1:2
Press any key to continue . . .

This could probably be cleaned up with some anonymous delegates, but I'll leave that up to you.

EDIT: And NoBugz demonstrates the power of anonymous methods...so, consider mine more oldschool :P

Create a .txt file if doesn't exist, and if it does append a new line

 else if (File.Exists(path)) 
{ 
  using (StreamWriter w = File.AppendText(path))
        {
            w.WriteLine("The next line!"); 
            w.Close();
        }
 } 

ActiveXObject in Firefox or Chrome (not IE!)

ActiveX is supported by Chrome.

Chrome check parameters defined in : control panel/Internet option/Security.

Nevertheless,if it's possible to define four different area with IE, Chrome only check "Internet" area.

How to parse a JSON string to an array using Jackson

I sorted this problem by verifying the json on JSONLint.com and then using Jackson. Below is the code for the same.

 Main Class:-

String jsonStr = "[{\r\n" + "       \"name\": \"John\",\r\n" + "        \"city\": \"Berlin\",\r\n"
                + "         \"cars\": [\r\n" + "            \"FIAT\",\r\n" + "          \"Toyata\"\r\n"
                + "     ],\r\n" + "     \"job\": \"Teacher\"\r\n" + "   },\r\n" + " {\r\n"
                + "     \"name\": \"Mark\",\r\n" + "        \"city\": \"Oslo\",\r\n" + "        \"cars\": [\r\n"
                + "         \"VW\",\r\n" + "            \"Toyata\"\r\n" + "     ],\r\n"
                + "     \"job\": \"Doctor\"\r\n" + "    }\r\n" + "]";

        ObjectMapper mapper = new ObjectMapper();

        MyPojo jsonObj[] = mapper.readValue(jsonStr, MyPojo[].class);

        for (MyPojo itr : jsonObj) {

            System.out.println("Val of getName is: " + itr.getName());
            System.out.println("Val of getCity is: " + itr.getCity());
            System.out.println("Val of getJob is: " + itr.getJob());
            System.out.println("Val of getCars is: " + itr.getCars() + "\n");

        }

POJO:

public class MyPojo {

private List<String> cars = new ArrayList<String>();

private String name;

private String job;

private String city;

public List<String> getCars() {
    return cars;
}

public void setCars(List<String> cars) {
    this.cars = cars;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public String getJob() {
    return job;
}

public void setJob(String job) {
    this.job = job;
}

public String getCity() {
    return city;
}

public void setCity(String city) {
    this.city = city;
} }

  RESULT:-
         Val of getName is: John
         Val of getCity is: Berlin
         Val of getJob is: Teacher
         Val of getCars is: [FIAT, Toyata]

          Val of getName is: Mark
          Val of getCity is: Oslo
          Val of getJob is: Doctor
          Val of getCars is: [VW, Toyata]

Running Java Program from Command Line Linux

If your Main class is in a package called FileManagement, then try:

java -cp . FileManagement.Main

in the parent folder of the FileManagement folder.

If your Main class is not in a package (the default package) then cd to the FileManagement folder and try:

java -cp . Main

More info about the CLASSPATH and how the JRE find classes:

How do I set a column value to NULL in SQL Server Management Studio?

If you are using the table interface you can type in NULL (all caps)

otherwise you can run an update statement where you could:

Update table set ColumnName = NULL where [Filter for record here]

Simple if else onclick then do?

The preferred modern method is to use addEventListener either by adding the event listener direct to the element or to a parent of the elements (delegated).

An example, using delegated events, might be

_x000D_
_x000D_
var box = document.getElementById('box');_x000D_
_x000D_
document.getElementById('buttons').addEventListener('click', function(evt) {_x000D_
  var target = evt.target;_x000D_
  if (target.id === 'yes') {_x000D_
    box.style.backgroundColor = 'red';_x000D_
  } else if (target.id === 'no') {_x000D_
    box.style.backgroundColor = 'green';_x000D_
  } else {_x000D_
    box.style.backgroundColor = 'purple';_x000D_
  }_x000D_
}, false);
_x000D_
#box {_x000D_
  width: 200px;_x000D_
  height: 200px;_x000D_
  background-color: red;_x000D_
}_x000D_
#buttons {_x000D_
  margin-top: 50px;_x000D_
}
_x000D_
<div id='box'></div>_x000D_
<div id='buttons'>_x000D_
  <button id='yes'>yes</button>_x000D_
  <button id='no'>no</button>_x000D_
  <p>Click one of the buttons above.</p>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Best way to encode text data for XML

Here is a single line solution using the XElements. I use it in a very small tool. I don't need it a second time so I keep it this way. (Its dirdy doug)

StrVal = (<x a=<%= StrVal %>>END</x>).ToString().Replace("<x a=""", "").Replace(">END</x>", "")

Oh and it only works in VB not in C#

How to remove a directory from git repository?

To remove folder/directory only from git repository and not from the local try 3 simple commands.


Steps to remove directory

git rm -r --cached FolderName
git commit -m "Removed folder from repository"
git push origin master

Steps to ignore that folder in next commits

To ignore that folder from next commits make one file in root folder (main project directory where the git is initialized) named .gitignore and put that folder name into it. You can ignore as many files/folders as you want

.gitignore file will look like this

/FolderName

remove directory

How to install a specific version of a ruby gem?

Linux

To install different version of ruby, check the latest version of package using apt as below:

$ apt-cache madison ruby
      ruby |    1:1.9.3 | http://ftp.uk.debian.org/debian/ wheezy/main amd64 Packages
      ruby |        4.5 | http://ftp.uk.debian.org/debian/ squeeze/main amd64 Packages

Then install it:

$ sudo apt-get install ruby=1:1.9.3

To check what's the current version, run:

$ gem --version # Check for the current user.
$ sudo gem --version # Check globally.

If the version is still old, you may try to switch the version to new by using ruby version manager (rvm) by:

rvm 1.9.3

Note: You may prefix it by sudo if rvm was installed globally. Or run /usr/local/rvm/scripts/rvm if your command rvm is not in your global PATH. If rvm installation process failed, see the troubleshooting section.


Troubleshooting:

  • If you still have the old version, you may try to install rvm (ruby version manager) via:

    sudo apt-get install curl # Install curl first
    curl -sSL https://get.rvm.io | bash -s stable --ruby # Install only for the user.
    #or:# curl -sSL https://get.rvm.io | sudo bash -s stable --ruby # Install globally. 
    

    then if installed locally (only for current user), load rvm via:

    source /usr/local/rvm/scripts/rvm; rvm 1.9.3
    

    if globally (for all users), then:

    sudo bash -c "source /usr/local/rvm/scripts/rvm; rvm 1.9.3"
    
  • if you still having problem with the new ruby version, try to install it by rvm via:

    source /usr/local/rvm/scripts/rvm && rvm install ruby-1.9.3 # Locally.
    sudo bash -c "source /usr/local/rvm/scripts/rvm && rvm install ruby-1.9.3" # Globally.
    
  • if you'd like to install some gems globally and you have rvm already installed, you may try:

    rvmsudo gem install [gemname]
    

    instead of:

      gem install [gemname] # or:
      sudo gem install [gemname]
    

Note: It's prefered to NOT use sudo to work with RVM gems. When you do sudo you are running commands as root, another user in another shell and hence all of the setup that RVM has done for you is ignored while the command runs under sudo (such things as GEM_HOME, etc...). So to reiterate, as soon as you 'sudo' you are running as the root system user which will clear out your environment as well as any files it creates are not able to be modified by your user and will result in strange things happening.

No resource found that matches the given name: attr 'android:keyboardNavigationCluster'. when updating to Support Library 26.0.0

I was able to resolve it by updating sdk version and tools in gradle compileSdkVersion 26 buildToolsVersion "26.0.1"

and support library 26.0.1 https://developer.android.com/topic/libraries/support-library/revisions.html#26-0-1

How to allow only a number (digits and decimal point) to be typed in an input?

I wrote a working CodePen example to demonstrate a great way of filtering numeric user input. The directive currently only allows positive integers, but the regex can easily be updated to support any desired numeric format.

My directive is easy to use:

<input type="text" ng-model="employee.age" valid-number />

The directive is very easy to understand:

var app = angular.module('myApp', []);

app.controller('MainCtrl', function($scope) {
});

app.directive('validNumber', function() {
  return {
    require: '?ngModel',
    link: function(scope, element, attrs, ngModelCtrl) {
      if(!ngModelCtrl) {
        return; 
      }

      ngModelCtrl.$parsers.push(function(val) {
        if (angular.isUndefined(val)) {
            var val = '';
        }
        var clean = val.replace( /[^0-9]+/g, '');
        if (val !== clean) {
          ngModelCtrl.$setViewValue(clean);
          ngModelCtrl.$render();
        }
        return clean;
      });

      element.bind('keypress', function(event) {
        if(event.keyCode === 32) {
          event.preventDefault();
        }
      });
    }
  };
});

I want to emphasize that keeping model references out of the directive is important.

I hope you find this helpful.

Big thanks to Sean Christe and Chris Grimes for introducing me to the ngModelController

What is the difference between required and ng-required?

AngularJS form elements look for the required attribute to perform validation functions. ng-required allows you to set the required attribute depending on a boolean test (for instance, only require field B - say, a student number - if the field A has a certain value - if you selected "student" as a choice)

As an example, <input required> and <input ng-required="true"> are essentially the same thing

If you are wondering why this is this way, (and not just make <input required="true"> or <input required="false">), it is due to the limitations of HTML - the required attribute has no associated value - its mere presence means (as per HTML standards) that the element is required - so angular needs a way to set/unset required value (required="false" would be invalid HTML)

C#, Looping through dataset and show each record from a dataset column

DateTime TaskStart = DateTime.Parse(dr["TaskStart"].ToString());

Keras input explanation: input_shape, units, batch_size, dim, etc

Units:

The amount of "neurons", or "cells", or whatever the layer has inside it.

It's a property of each layer, and yes, it's related to the output shape (as we will see later). In your picture, except for the input layer, which is conceptually different from other layers, you have:

  • Hidden layer 1: 4 units (4 neurons)
  • Hidden layer 2: 4 units
  • Last layer: 1 unit

Shapes

Shapes are consequences of the model's configuration. Shapes are tuples representing how many elements an array or tensor has in each dimension.

Ex: a shape (30,4,10) means an array or tensor with 3 dimensions, containing 30 elements in the first dimension, 4 in the second and 10 in the third, totaling 30*4*10 = 1200 elements or numbers.

The input shape

What flows between layers are tensors. Tensors can be seen as matrices, with shapes.

In Keras, the input layer itself is not a layer, but a tensor. It's the starting tensor you send to the first hidden layer. This tensor must have the same shape as your training data.

Example: if you have 30 images of 50x50 pixels in RGB (3 channels), the shape of your input data is (30,50,50,3). Then your input layer tensor, must have this shape (see details in the "shapes in keras" section).

Each type of layer requires the input with a certain number of dimensions:

  • Dense layers require inputs as (batch_size, input_size)
    • or (batch_size, optional,...,optional, input_size)
  • 2D convolutional layers need inputs as:
    • if using channels_last: (batch_size, imageside1, imageside2, channels)
    • if using channels_first: (batch_size, channels, imageside1, imageside2)
  • 1D convolutions and recurrent layers use (batch_size, sequence_length, features)

Now, the input shape is the only one you must define, because your model cannot know it. Only you know that, based on your training data.

All the other shapes are calculated automatically based on the units and particularities of each layer.

Relation between shapes and units - The output shape

Given the input shape, all other shapes are results of layers calculations.

The "units" of each layer will define the output shape (the shape of the tensor that is produced by the layer and that will be the input of the next layer).

Each type of layer works in a particular way. Dense layers have output shape based on "units", convolutional layers have output shape based on "filters". But it's always based on some layer property. (See the documentation for what each layer outputs)

Let's show what happens with "Dense" layers, which is the type shown in your graph.

A dense layer has an output shape of (batch_size,units). So, yes, units, the property of the layer, also defines the output shape.

  • Hidden layer 1: 4 units, output shape: (batch_size,4).
  • Hidden layer 2: 4 units, output shape: (batch_size,4).
  • Last layer: 1 unit, output shape: (batch_size,1).

Weights

Weights will be entirely automatically calculated based on the input and the output shapes. Again, each type of layer works in a certain way. But the weights will be a matrix capable of transforming the input shape into the output shape by some mathematical operation.

In a dense layer, weights multiply all inputs. It's a matrix with one column per input and one row per unit, but this is often not important for basic works.

In the image, if each arrow had a multiplication number on it, all numbers together would form the weight matrix.

Shapes in Keras

Earlier, I gave an example of 30 images, 50x50 pixels and 3 channels, having an input shape of (30,50,50,3).

Since the input shape is the only one you need to define, Keras will demand it in the first layer.

But in this definition, Keras ignores the first dimension, which is the batch size. Your model should be able to deal with any batch size, so you define only the other dimensions:

input_shape = (50,50,3)
    #regardless of how many images I have, each image has this shape        

Optionally, or when it's required by certain kinds of models, you can pass the shape containing the batch size via batch_input_shape=(30,50,50,3) or batch_shape=(30,50,50,3). This limits your training possibilities to this unique batch size, so it should be used only when really required.

Either way you choose, tensors in the model will have the batch dimension.

So, even if you used input_shape=(50,50,3), when keras sends you messages, or when you print the model summary, it will show (None,50,50,3).

The first dimension is the batch size, it's None because it can vary depending on how many examples you give for training. (If you defined the batch size explicitly, then the number you defined will appear instead of None)

Also, in advanced works, when you actually operate directly on the tensors (inside Lambda layers or in the loss function, for instance), the batch size dimension will be there.

  • So, when defining the input shape, you ignore the batch size: input_shape=(50,50,3)
  • When doing operations directly on tensors, the shape will be again (30,50,50,3)
  • When keras sends you a message, the shape will be (None,50,50,3) or (30,50,50,3), depending on what type of message it sends you.

Dim

And in the end, what is dim?

If your input shape has only one dimension, you don't need to give it as a tuple, you give input_dim as a scalar number.

So, in your model, where your input layer has 3 elements, you can use any of these two:

  • input_shape=(3,) -- The comma is necessary when you have only one dimension
  • input_dim = 3

But when dealing directly with the tensors, often dim will refer to how many dimensions a tensor has. For instance a tensor with shape (25,10909) has 2 dimensions.


Defining your image in Keras

Keras has two ways of doing it, Sequential models, or the functional API Model. I don't like using the sequential model, later you will have to forget it anyway because you will want models with branches.

PS: here I ignored other aspects, such as activation functions.

With the Sequential model:

from keras.models import Sequential  
from keras.layers import *  

model = Sequential()    

#start from the first hidden layer, since the input is not actually a layer   
#but inform the shape of the input, with 3 elements.    
model.add(Dense(units=4,input_shape=(3,))) #hidden layer 1 with input

#further layers:    
model.add(Dense(units=4)) #hidden layer 2
model.add(Dense(units=1)) #output layer   

With the functional API Model:

from keras.models import Model   
from keras.layers import * 

#Start defining the input tensor:
inpTensor = Input((3,))   

#create the layers and pass them the input tensor to get the output tensor:    
hidden1Out = Dense(units=4)(inpTensor)    
hidden2Out = Dense(units=4)(hidden1Out)    
finalOut = Dense(units=1)(hidden2Out)   

#define the model's start and end points    
model = Model(inpTensor,finalOut)

Shapes of the tensors

Remember you ignore batch sizes when defining layers:

  • inpTensor: (None,3)
  • hidden1Out: (None,4)
  • hidden2Out: (None,4)
  • finalOut: (None,1)

Change div height on button click

_x000D_
_x000D_
var ww1 = "";_x000D_
var ww2 = 0;_x000D_
var myVar1 ;_x000D_
var myVar2 ;_x000D_
function wm1(){_x000D_
  myVar1 =setInterval(w1, 15);_x000D_
}_x000D_
function wm2(){_x000D_
  myVar2 =setInterval(w2, 15);_x000D_
}_x000D_
function w1(){_x000D_
 ww1=document.getElementById('chartdiv').style.height;_x000D_
 ww2= ww1.replace("px", ""); _x000D_
    if(parseFloat(ww2) <= 200){_x000D_
document.getElementById('chartdiv').style.height = (parseFloat(ww2)+5) + 'px';_x000D_
    }else{_x000D_
      clearInterval(myVar1);_x000D_
    }_x000D_
}_x000D_
function w2(){_x000D_
 ww1=document.getElementById('chartdiv').style.height;_x000D_
 ww2= ww1.replace("px", ""); _x000D_
    if(parseFloat(ww2) >= 50){_x000D_
document.getElementById('chartdiv').style.height = (parseFloat(ww2)-5) + 'px';_x000D_
    }else{_x000D_
      clearInterval(myVar2);_x000D_
    }_x000D_
}
_x000D_
<html>_x000D_
  <head>    _x000D_
  </head>_x000D_
_x000D_
<body >_x000D_
    <button type="button" onClick = "wm1()">200px</button>_x000D_
    <button type="button" onClick = "wm2()">50px</button>_x000D_
    <div id="chartdiv" style="width: 100%; height: 50px; background-color:#ccc"></div>_x000D_
  _x000D_
  <div id="demo"></div>_x000D_
</body>
_x000D_
_x000D_
_x000D_

Dropping Unique constraint from MySQL table

For WAMP 3.0 : Click Structure Below Add 1 Column you will see '- Indexes' Click -Indexes and drop whichever index you want.

MySQL Stored procedure variables from SELECT statements

You simply need to enclose your SELECT statements in parentheses to indicate that they are subqueries:

SET cityLat = (SELECT cities.lat FROM cities WHERE cities.id = cityID);

Alternatively, you can use MySQL's SELECT ... INTO syntax. One advantage of this approach is that both cityLat and cityLng can be assigned from a single table-access:

SELECT lat, lng INTO cityLat, cityLng FROM cities WHERE id = cityID;

However, the entire procedure can be replaced with a single self-joined SELECT statement:

SELECT   b.*, HAVERSINE(a.lat, a.lng, b.lat, b.lng) AS dist
FROM     cities AS a, cities AS b
WHERE    a.id = cityID
ORDER BY dist
LIMIT    10;

Merging two arrayLists into a new arrayList, with no duplicates and in order, in Java

Java 8 Stream API can be used for the purpose,

ArrayList<String> list1 = new ArrayList<>();

list1.add("A");
list1.add("B");
list1.add("A");
list1.add("D");
list1.add("G");

ArrayList<String> list2 = new ArrayList<>();

list2.add("B");
list2.add("D");
list2.add("E");
list2.add("G");

List<String> noDup = Stream.concat(list1.stream(), list2.stream())
                     .distinct()
                     .collect(Collectors.toList());
noDup.forEach(System.out::println);

En passant, it shouldn't be forgetten that distinct() makes use of hashCode().

C - The %x format specifier

%08x means that every number should be printed at least 8 characters wide with filling all missing digits with zeros, e.g. for '1' output will be 00000001

Elegant way to report missing values in a data.frame

If you want to do it for particular column, then you can also use this

length(which(is.na(airquality[1])==T))

How to post an array of complex objects with JSON, jQuery to ASP.NET MVC Controller?

I've found an solution. I use an solution of Steve Gentile, jQuery and ASP.NET MVC – sending JSON to an Action – Revisited.

My ASP.NET MVC view code looks like:

function getplaceholders() {
        var placeholders = $('.ui-sortable');
        var results = new Array();
        placeholders.each(function() {
            var ph = $(this).attr('id');
            var sections = $(this).find('.sort');
            var section;

            sections.each(function(i, item) {
                var sid = $(item).attr('id');
                var o = { 'SectionId': sid, 'Placeholder': ph, 'Position': i };
                results.push(o);
            });
        });
        var postData = { widgets: results };
        var widgets = results;
        $.ajax({
            url: '/portal/Designer.mvc/SaveOrUpdate',
            type: 'POST',
            dataType: 'json',
            data: $.toJSON(widgets),
            contentType: 'application/json; charset=utf-8',
            success: function(result) {
                alert(result.Result);
            }
        });
    };

and my controller action is decorated with an custom attribute

[JsonFilter(Param = "widgets", JsonDataType = typeof(List<PageDesignWidget>))]
public JsonResult SaveOrUpdate(List<PageDesignWidget> widgets

Code for the custom attribute can be found here (the link is broken now).

Because the link is broken this is the code for the JsonFilterAttribute

public class JsonFilter : ActionFilterAttribute
{
    public string Param { get; set; }
    public Type JsonDataType { get; set; }
    public override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        if (filterContext.HttpContext.Request.ContentType.Contains("application/json"))
        {
            string inputContent;
            using (var sr = new StreamReader(filterContext.HttpContext.Request.InputStream))
            {
                inputContent = sr.ReadToEnd();
            }
            var result = JsonConvert.DeserializeObject(inputContent, JsonDataType);
            filterContext.ActionParameters[Param] = result;
        }
    }
}

JsonConvert.DeserializeObject is from Json.NET

Link: Serializing and Deserializing JSON with Json.NET

Uncaught SyntaxError: Failed to execute 'querySelector' on 'Document'

You are allowed to use IDs that start with a digit in your HTML5 documents:

The value must be unique amongst all the IDs in the element's home subtree and must contain at least one character. The value must not contain any space characters.

There are no other restrictions on what form an ID can take; in particular, IDs can consist of just digits, start with a digit, start with an underscore, consist of just punctuation, etc.

But querySelector method uses CSS3 selectors for querying the DOM and CSS3 doesn't support ID selectors that start with a digit:

In CSS, identifiers (including element names, classes, and IDs in selectors) can contain only the characters [a-zA-Z0-9] and ISO 10646 characters U+00A0 and higher, plus the hyphen (-) and the underscore (_); they cannot start with a digit, two hyphens, or a hyphen followed by a digit.

Use a value like b22 for the ID attribute and your code will work.

Since you want to select an element by ID you can also use .getElementById method:

document.getElementById('22')

Detecting a redirect in ajax request?

Welcome to the future!

Right now we have a "responseURL" property from xhr object. YAY!

See How to get response url in XMLHttpRequest?

However, jQuery (at least 1.7.1) doesn't give an access to XMLHttpRequest object directly. You can use something like this:

var xhr;
var _orgAjax = jQuery.ajaxSettings.xhr;
jQuery.ajaxSettings.xhr = function () {
  xhr = _orgAjax();
  return xhr;
};

jQuery.ajax('http://test.com', {
  success: function(responseText) {
    console.log('responseURL:', xhr.responseURL, 'responseText:', responseText);
  }
});

It's not a clean solution and i suppose jQuery team will make something for responseURL in the future releases.

TIP: just compare original URL with responseUrl. If it's equal then no redirect was given. If it's "undefined" then responseUrl is probably not supported. However as Nick Garvey said, AJAX request never has the opportunity to NOT follow the redirect but you may resolve a number of tasks by using responseUrl property.

How can I tell where mongoDB is storing data? (its not in the default /data/db!)

On MongoDB 4.4+ and on CentOS 8, I found the path by running:

grep dbPath /etc/mongod.conf

How can I check for Python version in a program that uses new language features?

I just found this question after a quick search whilst trying to solve the problem myself and I've come up with a hybrid based on a few of the suggestions above.

I like DevPlayer's idea of using a wrapper script, but the downside is that you end up maintaining multiple wrappers for different OSes, so I decided to write the wrapper in python, but use the same basic "grab the version by running the exe" logic and came up with this.

I think it should work for 2.5 and onwards. I've tested it on 2.66, 2.7.0 and 3.1.2 on Linux and 2.6.1 on OS X so far.

import sys, subprocess
args = [sys.executable,"--version"]

output, error = subprocess.Popen(args ,stdout = subprocess.PIPE, stderr = subprocess.PIPE).communicate()
print("The version is: '%s'"  %error.decode(sys.stdout.encoding).strip("qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLMNBVCXZ,.+ \n") )

Yes, I know the final decode/strip line is horrible, but I just wanted to quickly grab the version number. I'm going to refine that.

This works well enough for me for now, but if anyone can improve it (or tell me why it's a terrible idea) that'd be cool too.

How to insert 1000 rows at a time

DECLARE @X INT = 1
WHILE @X <=1000
BEGIN
    INSERT INTO dbo.YourTable (ID, Age)
    VALUES(@X,LEFT(RAND()*100,2) 
    SET @X+=1
END;

    enter code here
DECLARE @X INT = 1
WHILE @X <=1000
BEGIN
    INSERT INTO dbo.YourTable (ID, Age)
    VALUES(@X,LEFT(RAND()*100,2) 
    SET @X+=1
END;

Jquery - animate height toggle

Worked for me:

$(".filter-mobile").click(function() {
   if ($("#menuProdutos").height() > 0) {
      $("#menuProdutos").animate({
         height: 0
      }, 200);
   } else {
      $("#menuProdutos").animate({
         height: 500
      }, 200);
   }
});

how to increase the limit for max.print in R

Use the options command, e.g. options(max.print=1000000).

See ?options:

 ‘max.print’: integer, defaulting to ‘99999’.  ‘print’ or ‘show’
      methods can make use of this option, to limit the amount of
      information that is printed, to something in the order of
      (and typically slightly less than) ‘max.print’ _entries_.

How do I force "git pull" to overwrite local files?

It seems like most answers here are focused on the master branch; however, there are times when I'm working on the same feature branch in two different places and I want a rebase in one to be reflected in the other without a lot of jumping through hoops.

Based on a combination of RNA's answer and torek's answer to a similar question, I've come up with this which works splendidly:

git fetch
git reset --hard @{u}

Run this from a branch and it'll only reset your local branch to the upstream version.

This can be nicely put into a git alias (git forcepull) as well:

git config alias.forcepull "!git fetch ; git reset --hard @{u}"

Or, in your .gitconfig file:

[alias]
  forcepull = "!git fetch ; git reset --hard @{u}"

Enjoy!

Regex for numbers only

^\d+$, which is "start of string", "1 or more digits", "end of string" in English.

selectOneMenu ajax events

The PrimeFaces ajax events sometimes are very poorly documented, so in most cases you must go to the source code and check yourself.

p:selectOneMenu supports change event:

<p:selectOneMenu ..>
    <p:ajax event="change" update="msgtext"
        listener="#{post.subjectSelectionChanged}" />
    <!--...-->
</p:selectOneMenu>

which triggers listener with AjaxBehaviorEvent as argument in signature:

public void subjectSelectionChanged(final AjaxBehaviorEvent event)  {...}

Golang append an item to a slice

Explanation (read inline comments):


package main

import (
    "fmt"
)

var a = make([]int, 7, 8)
// A slice is a descriptor of an array segment. 
// It consists of a pointer to the array, the length of the segment, and its capacity (the maximum length of the segment).
// The length is the number of elements referred to by the slice.
// The capacity is the number of elements in the underlying array (beginning at the element referred to by the slice pointer).
// |-> Refer to: https://blog.golang.org/go-slices-usage-and-internals -> "Slice internals" section

func Test(slice []int) {
    // slice receives a copy of slice `a` which point to the same array as slice `a`
    slice[6] = 10
    slice = append(slice, 100)
    // since `slice` capacity is 8 & length is 7, it can add 100 and make the length 8
    fmt.Println(slice, len(slice), cap(slice), " << Test 1")
    slice = append(slice, 200)
    // since `slice` capacity is 8 & length also 8, slice has to make a new slice 
    // - with double of size with point to new array (see Reference 1 below).
    // (I'm also confused, why not (n+1)*2=20). But make a new slice of 16 capacity).
    slice[6] = 13 // make sure, it's a new slice :)
    fmt.Println(slice, len(slice), cap(slice), " << Test 2")
}

func main() {
    for i := 0; i < 7; i++ {
        a[i] = i
    }

    fmt.Println(a, len(a), cap(a))
    Test(a)
    fmt.Println(a, len(a), cap(a))
    fmt.Println(a[:cap(a)], len(a), cap(a))
    // fmt.Println(a[:cap(a)+1], len(a), cap(a)) -> this'll not work
}

Output:

[0 1 2 3 4 5 6] 7 8
[0 1 2 3 4 5 10 100] 8 8  << Test 1
[0 1 2 3 4 5 13 100 200] 9 16  << Test 2
[0 1 2 3 4 5 10] 7 8
[0 1 2 3 4 5 10 100] 7 8

Reference 1: https://blog.golang.org/go-slices-usage-and-internals

func AppendByte(slice []byte, data ...byte) []byte {
    m := len(slice)
    n := m + len(data)
    if n > cap(slice) { // if necessary, reallocate
        // allocate double what's needed, for future growth.
        newSlice := make([]byte, (n+1)*2)
        copy(newSlice, slice)
        slice = newSlice
    }
    slice = slice[0:n]
    copy(slice[m:n], data)
    return slice
}

Android Intent Cannot resolve constructor

Same Error was coming with my code in Activity but not in Fragment. Showing constructor error for different line like new Intent( From.this, To.class) and new ArrayList<> etc.

Fixed using closing Android Studio and moving the repository to other location and opening the the project once again. Fixed the problem.

Seems like Android Studio building problem.

How to show image using ImageView in Android

shoud be @drawable/image where image could have any extension like: image.png, image.xml, image.gif. Android will automatically create a reference in R class with its name, so you cannot have in any drawable folder image.png and image.gif.

How do I concatenate two text files in PowerShell?

I think the "powershell way" could be :

set-content destination.log -value (get-content c:\FileToAppend_*.log )

Line continue character in C#

@"string here
that is long you mean"

But be careful, because

@"string here
           and space before this text
     means the space is also a part of the string"

It also escapes things in the string

@"c:\\folder" // c:\\folder
@"c:\folder" // c:\folder
"c:\\folder" // c:\folder

Related

How to show shadow around the linearlayout in Android?

set this xml drwable as your background;---

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

<!-- Bottom 2dp Shadow -->
<item>
    <shape android:shape="rectangle" >
        <solid android:color="#d8d8d8" />-->Your shadow color<--

        <corners android:radius="15dp" />
    </shape>
</item>

<!-- White Top color -->
<item android:bottom="3px" android:left="3px" android:right="3px" android:top="3px">-->here you can customize the shadow size<---
    <shape android:shape="rectangle" >
        <solid android:color="#FFFFFF" />

        <corners android:radius="15dp" />
    </shape>
</item>

</layer-list>

Open URL in new window with JavaScript

Use window.open():

<a onclick="window.open(document.URL, '_blank', 'location=yes,height=570,width=520,scrollbars=yes,status=yes');">
  Share Page
</a>

This will create a link titled Share Page which opens the current url in a new window with a height of 570 and width of 520.

How to use Apple's new .p8 certificate for APNs in firebase console

Apple have recently made new changes in APNs and now apple insist us to use "Token Based Authentication" instead of the traditional ways which we are using for push notification.

So does not need to worry about their expiration and this p8 certificates are for both development and production so again no need to generate 2 separate certificate for each mode.

To generate p8 just go to your developer account and select this option "Apple Push Notification Authentication Key (Sandbox & Production)"

enter image description here

Then will generate directly p8 file.

I hope this will solve your issue.

Read this new APNs changes from apple: https://developer.apple.com/videos/play/wwdc2016/724/

Also you can read this: https://developer.apple.com/library/prerelease/content/documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/Chapters/APNsProviderAPI.html

Unresolved reference issue in PyCharm

  1. check for __init__.py file in src folder
  2. add the src folder as a source root
  3. Then make sure to add add sources to your PYTHONPATH (see above)
  4. in PyCharm menu select: File --> Invalidate Caches / Restart

Converting HTML files to PDF

Amyuni WebkitPDF could be used with JNI for a Windows-only solution. This is a HTML to PDF/XAML conversion library, free for commercial and non-commercial use.

If the output files are not needed immediately, for better scalability it may be better to have a queue and a few background processes taking items from there, converting them and storing then on the database or file system.

usual disclaimer applies

Openstreetmap: embedding map in webpage (like Google Maps)

Simple OSM Slippy Map Demo/Example

Click on "Run code snippet" to see an embedded OpenStreetMap slippy map with a marker on it. This was created with Leaflet.

Code

_x000D_
_x000D_
// Where you want to render the map.
var element = document.getElementById('osm-map');

// Height has to be set. You can do this in CSS too.
element.style = 'height:300px;';

// Create Leaflet map on map element.
var map = L.map(element);

// Add OSM tile leayer to the Leaflet map.
L.tileLayer('http://{s}.tile.osm.org/{z}/{x}/{y}.png', {
    attribution: '&copy; <a href="http://osm.org/copyright">OpenStreetMap</a> contributors'
}).addTo(map);

// Target's GPS coordinates.
var target = L.latLng('47.50737', '19.04611');

// Set map's center to target with zoom 14.
map.setView(target, 14);

// Place a marker on the same location.
L.marker(target).addTo(map);
_x000D_
<script src="https://unpkg.com/[email protected]/dist/leaflet.js"></script>
<link href="https://unpkg.com/[email protected]/dist/leaflet.css" rel="stylesheet"/>
<div id="osm-map"></div>
_x000D_
_x000D_
_x000D_

Specs

  • Uses OpenStreetMaps.
  • Centers the map to the target GPS.
  • Places a marker on the target GPS.
  • Only uses Leaflet as a dependency.

Note:

I used the CDN version of Leaflet here, but you can download the files so you can serve and include them from your own host.

OperationalError, no such column. Django

You did not migrated all changes you made in model. so 1) python manage.py makemigrations 2) python manage.py migrate 3) python manag.py runserver it works 100%

Strings as Primary Keys in SQL Database

Strings are slower in joins and in real life they are very rarely really unique (even when they are supposed to be). The only advantage is that they can reduce the number of joins if you are joining to the primary table only to get the name. However, strings are also often subject to change thus creating the problem of having to fix all related records when the company name changes or the person gets married. This can be a huge performance hit and if all tables that should be related somehow are not related (this happens more often than you think), then you might have data mismatches as well. An integer that will never change through the life of the record is a far safer choice from a data integrity standpoint as well as from a performance standpoint. Natural keys are usually not so good for maintenance of the data.

I also want to point out that the best of both worlds is often to use an autoincrementing key (or in some specialized cases, a GUID) as the PK and then put a unique index on the natural key. You get the faster joins, you don;t get duplicate records, and you don't have to update a million child records because a company name changed.

Why does instanceof return false for some literals?

 typeof(text) === 'string' || text instanceof String; 

you can use this, it will work for both case as

  1. var text="foo"; // typeof will work

  2. String text= new String("foo"); // instanceof will work

Python concatenate text files

def concatFiles():
    path = 'input/'
    files = os.listdir(path)
    for idx, infile in enumerate(files):
        print ("File #" + str(idx) + "  " + infile)
    concat = ''.join([open(path + f).read() for f in files])
    with open("output_concatFile.txt", "w") as fo:
        fo.write(path + concat)

if __name__ == "__main__":
    concatFiles()

Tomcat 404 error: The origin server did not find a current representation for the target resource or is not willing to disclose that one exists

Hope this helps. From eclipse, you right click the project -> Run As -> Run on Server and then it worked for me. I used Eclipse Jee Neon and Apache Tomcat 9.0. :)

I just removed the head portion in index.html file and it worked fine.This is the head tag in html file

Can I use multiple versions of jQuery on the same page?

After looking at this and trying it out I found it actually didn't allow more than one instance of jquery to run at a time. After searching around I found that this did just the trick and was a whole lot less code.

    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js" type="text/javascript"></script>
    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js" type="text/javascript"></script>
    <script>var $j = jQuery.noConflict(true);</script>
    <script>
      $(document).ready(function(){
       console.log($().jquery); // This prints v1.4.2
       console.log($j().jquery); // This prints v1.9.1
      });
   </script>

So then adding the "j" after the "$" was all I needed to do.

$j(function () {
        $j('.button-pro').on('click', function () {
            var el = $('#cnt' + this.id.replace('btn', ''));
            $j('#contentnew > div').not(el).animate({
                height: "toggle",
                opacity: "toggle"
            }, 100).hide();
            el.toggle();
        });
    });

How do I increase the RAM and set up host-only networking in Vagrant?

To increase the memory or CPU count when using Vagrant 2, add this to your Vagrantfile

Vagrant.configure("2") do |config|
    # usual vagrant config here

    config.vm.provider "virtualbox" do |v|
        v.memory = 1024
        v.cpus = 2
    end
end

Counting unique values in a column in pandas dataframe like in Qlik?

Count distinct values, use nunique:

df['hID'].nunique()
5

Count only non-null values, use count:

df['hID'].count()
8

Count total values including null values, use the size attribute:

df['hID'].size
8

Edit to add condition

Use boolean indexing:

df.loc[df['mID']=='A','hID'].agg(['nunique','count','size'])

OR using query:

df.query('mID == "A"')['hID'].agg(['nunique','count','size'])

Output:

nunique    5
count      5
size       5
Name: hID, dtype: int64

How to get previous page url using jquery

var from = document.referrer;
console.log(from);

document.referrer won't be always available.

Use latest version of Internet Explorer in the webbrowser control

I know this has been posted but here is a current version for dotnet 4.5 above that I use. I recommend to use the default browser emulation respecting doctype

InternetExplorerFeatureControl.Instance.BrowserEmulation = DocumentMode.DefaultRespectDocType;

internal class InternetExplorerFeatureControl
{
    private static readonly Lazy<InternetExplorerFeatureControl> LazyInstance = new Lazy<InternetExplorerFeatureControl>(() => new InternetExplorerFeatureControl());
    private const string RegistryLocation = @"SOFTWARE\Microsoft\Internet Explorer\Main\FeatureControl";
    private readonly RegistryView _registryView = Environment.Is64BitOperatingSystem && Environment.Is64BitProcess ? RegistryView.Registry64 : RegistryView.Registry32;
    private readonly string _processName;
    private readonly Version _version;

    #region Feature Control Strings (A)

    private const string FeatureRestrictAboutProtocolIe7 = @"FEATURE_RESTRICT_ABOUT_PROTOCOL_IE7";
    private const string FeatureRestrictAboutProtocol = @"FEATURE_RESTRICT_ABOUT_PROTOCOL";

    #endregion

    #region Feature Control Strings (B)

    private const string FeatureBrowserEmulation = @"FEATURE_BROWSER_EMULATION";

    #endregion

    #region Feature Control Strings (G)

    private const string FeatureGpuRendering = @"FEATURE_GPU_RENDERING";

    #endregion

    #region Feature Control Strings (L)

    private const string FeatureBlockLmzScript = @"FEATURE_BLOCK_LMZ_SCRIPT";

    #endregion

    internal InternetExplorerFeatureControl()
    {
        _processName = $"{Process.GetCurrentProcess().ProcessName}.exe";
        using (var webBrowser = new WebBrowser())
            _version = webBrowser.Version;
    }

    internal static InternetExplorerFeatureControl Instance => LazyInstance.Value;

    internal RegistryHive RegistryHive { get; set; } = RegistryHive.CurrentUser;

    private int GetFeatureControl(string featureControl)
    {
        using (var currentUser = RegistryKey.OpenBaseKey(RegistryHive.CurrentUser, _registryView))
        {
            using (var key = currentUser.CreateSubKey($"{RegistryLocation}\\{featureControl}", false))
            {
                if (key.GetValue(_processName) is int value)
                {
                    return value;
                }
                return -1;
            }
        }
    }

    private void SetFeatureControl(string featureControl, int value)
    {
        using (var currentUser = RegistryKey.OpenBaseKey(RegistryHive, _registryView))
        {
            using (var key = currentUser.CreateSubKey($"{RegistryLocation}\\{featureControl}", true))
            {
                key.SetValue(_processName, value, RegistryValueKind.DWord);
            }
        }
    }

    #region Internet Feature Controls (A)

    /// <summary>
    /// Windows Internet Explorer 8 and later. When enabled, feature disables the "about:" protocol. For security reasons, applications that host the WebBrowser Control are strongly encouraged to enable this feature.
    /// By default, this feature is enabled for Windows Internet Explorer and disabled for applications hosting the WebBrowser Control.To enable this feature using the registry, add the name of your executable file to the following setting.
    /// </summary>
    internal bool AboutProtocolRestriction
    {
        get
        {
            if (_version.Major < 8)
                throw new NotSupportedException($"{AboutProtocolRestriction} requires Internet Explorer 8 and Later.");
            var releaseVersion = new Version(8, 0, 6001, 18702);
            return Convert.ToBoolean(GetFeatureControl(_version >= releaseVersion ? FeatureRestrictAboutProtocolIe7 : FeatureRestrictAboutProtocol));
        }
        set
        {
            if (_version.Major < 8)
                throw new NotSupportedException($"{AboutProtocolRestriction} requires Internet Explorer 8 and Later.");
            var releaseVersion = new Version(8, 0, 6001, 18702);
            SetFeatureControl(_version >= releaseVersion ? FeatureRestrictAboutProtocolIe7 : FeatureRestrictAboutProtocol, Convert.ToInt16(value));
        }
    }

    #endregion

    #region Internet Feature Controls (B)

    /// <summary>
    /// Windows Internet Explorer 8 and later. Defines the default emulation mode for Internet Explorer and supports the following values.
    /// </summary>
    internal DocumentMode BrowserEmulation
    {
        get
        {
            if (_version.Major < 8)
                throw new NotSupportedException($"{nameof(BrowserEmulation)} requires Internet Explorer 8 and Later.");
            var value = GetFeatureControl(FeatureBrowserEmulation);
            if (Enum.IsDefined(typeof(DocumentMode), value))
            {
                return (DocumentMode)value;
            }
            return DocumentMode.NotSet;
        }
        set
        {
            if (_version.Major < 8)
                throw new NotSupportedException($"{nameof(BrowserEmulation)} requires Internet Explorer 8 and Later.");
            var tmp = value;
            if (value == DocumentMode.DefaultRespectDocType)
                tmp = DefaultRespectDocType;
            else if (value == DocumentMode.DefaultOverrideDocType)
                tmp = DefaultOverrideDocType;
            SetFeatureControl(FeatureBrowserEmulation, (int)tmp);
        }
    }

    #endregion

    #region Internet Feature Controls (G)

    /// <summary>
    /// Internet Explorer 9. Enables Internet Explorer to use a graphics processing unit (GPU) to render content. This dramatically improves performance for webpages that are rich in graphics.
    /// By default, this feature is enabled for Internet Explorer and disabled for applications hosting the WebBrowser Control.To enable this feature by using the registry, add the name of your executable file to the following setting.
    /// Note: GPU rendering relies heavily on the quality of your video drivers. If you encounter problems running Internet Explorer with GPU rendering enabled, you should verify that your video drivers are up to date and that they support hardware accelerated graphics.
    /// </summary>
    internal bool GpuRendering
    {
        get
        {
            if (_version.Major < 9)
                throw new NotSupportedException($"{nameof(GpuRendering)} requires Internet Explorer 9 and Later.");
            return Convert.ToBoolean(GetFeatureControl(FeatureGpuRendering));
        }
        set
        {
            if (_version.Major < 9)
                throw new NotSupportedException($"{nameof(GpuRendering)} requires Internet Explorer 9 and Later.");
            SetFeatureControl(FeatureGpuRendering, Convert.ToInt16(value));
        }
    }

    #endregion

    #region Internet Feature Controls (L)

    /// <summary>
    /// Internet Explorer 7 and later. When enabled, feature allows scripts stored in the Local Machine zone to be run only in webpages loaded from the Local Machine zone or by webpages hosted by sites in the Trusted Sites list. For more information, see Security and Compatibility in Internet Explorer 7.
    /// By default, this feature is enabled for Internet Explorer and disabled for applications hosting the WebBrowser Control.To enable this feature by using the registry, add the name of your executable file to the following setting.
    /// </summary>
    internal bool LocalScriptBlocking
    {
        get
        {
            if (_version.Major < 7)
                throw new NotSupportedException($"{nameof(LocalScriptBlocking)} requires Internet Explorer 7 and Later.");
            return Convert.ToBoolean(GetFeatureControl(FeatureBlockLmzScript));
        }
        set
        {
            if (_version.Major < 7)
                throw new NotSupportedException($"{nameof(LocalScriptBlocking)} requires Internet Explorer 7 and Later.");
            SetFeatureControl(FeatureBlockLmzScript, Convert.ToInt16(value));
        }
    }

    #endregion


    private DocumentMode DefaultRespectDocType
    {
        get
        {
            if (_version.Major >= 11)
                return DocumentMode.InternetExplorer11RespectDocType;
            switch (_version.Major)
            {
                case 10:
                    return DocumentMode.InternetExplorer10RespectDocType;
                case 9:
                    return DocumentMode.InternetExplorer9RespectDocType;
                case 8:
                    return DocumentMode.InternetExplorer8RespectDocType;
                default:
                    throw new ArgumentOutOfRangeException();
            }
        }
    }

    private DocumentMode DefaultOverrideDocType
    {
        get
        {
            if (_version.Major >= 11)
                return DocumentMode.InternetExplorer11OverrideDocType;
            switch (_version.Major)
            {
                case 10:
                    return DocumentMode.InternetExplorer10OverrideDocType;
                case 9:
                    return DocumentMode.InternetExplorer9OverrideDocType;
                case 8:
                    return DocumentMode.InternetExplorer8OverrideDocType;
                default:
                    throw new ArgumentOutOfRangeException();
            }
        }
    }
}

internal enum DocumentMode
{
    NotSet = -1,
    [Description("Webpages containing standards-based !DOCTYPE directives are displayed in IE latest installed version mode.")]
    DefaultRespectDocType,
    [Description("Webpages are displayed in IE latest installed version mode, regardless of the declared !DOCTYPE directive.  Failing to declare a !DOCTYPE directive could causes the page to load in Quirks.")]
    DefaultOverrideDocType,
    [Description(
        "Internet Explorer 11. Webpages are displayed in IE11 edge mode, regardless of the declared !DOCTYPE directive. Failing to declare a !DOCTYPE directive causes the page to load in Quirks."
    )] InternetExplorer11OverrideDocType = 11001,

    [Description(
        "IE11. Webpages containing standards-based !DOCTYPE directives are displayed in IE11 edge mode. Default value for IE11."
    )] InternetExplorer11RespectDocType = 11000,

    [Description(
        "Internet Explorer 10. Webpages are displayed in IE10 Standards mode, regardless of the !DOCTYPE directive."
    )] InternetExplorer10OverrideDocType = 10001,

    [Description(
        "Internet Explorer 10. Webpages containing standards-based !DOCTYPE directives are displayed in IE10 Standards mode. Default value for Internet Explorer 10."
    )] InternetExplorer10RespectDocType = 10000,

    [Description(
        "Windows Internet Explorer 9. Webpages are displayed in IE9 Standards mode, regardless of the declared !DOCTYPE directive. Failing to declare a !DOCTYPE directive causes the page to load in Quirks."
    )] InternetExplorer9OverrideDocType = 9999,

    [Description(
        "Internet Explorer 9. Webpages containing standards-based !DOCTYPE directives are displayed in IE9 mode. Default value for Internet Explorer 9.\r\n" +
        "Important  In Internet Explorer 10, Webpages containing standards - based !DOCTYPE directives are displayed in IE10 Standards mode."
    )] InternetExplorer9RespectDocType = 9000,

    [Description(
        "Webpages are displayed in IE8 Standards mode, regardless of the declared !DOCTYPE directive. Failing to declare a !DOCTYPE directive causes the page to load in Quirks."
    )] InternetExplorer8OverrideDocType = 8888,

    [Description(
        "Webpages containing standards-based !DOCTYPE directives are displayed in IE8 mode. Default value for Internet Explorer 8\r\n" +
        "Important  In Internet Explorer 10, Webpages containing standards - based !DOCTYPE directives are displayed in IE10 Standards mode."
    )] InternetExplorer8RespectDocType = 8000,

    [Description(
        "Webpages containing standards-based !DOCTYPE directives are displayed in IE7 Standards mode. Default value for applications hosting the WebBrowser Control."
    )] InternetExplorer7RespectDocType = 7000
}

How do I get the function name inside a function in PHP?

You can use the magic constants __METHOD__ (includes the class name) or __FUNCTION__ (just function name) depending on if it's a method or a function... =)

Apache Server (xampp) doesn't run on Windows 10 (Port 80)

I had the same issue and none of the above solutions worked for me.

Apache uses both ports 80 and 443 (for HTTPS) and both must be ready to be used for Apache to start successfully. Only port 80 might not be enough.

I found in my case that when running VMWare Workstation I had the port 443 used by the VMware sharing.

You have to disable sharing in the VMware main Preferences or change the port in this section.

After that as long as you have no other server hooked to the port 80 (see above solutions) then you should be able to start Apache or NGinx on XAMPP or any other Windows stack application.

I hope this will help other users.

How to set enum to null

Color? color = null;

or you can use

Color? color = new Color?();

example where assigning null wont work

color = x == 5 ? Color.Red : x == 9 ? Color.Black : null ; 

so you can use :

 color = x == 5 ? Color.Red : x == 9 ? Color.Black : new Color?(); 

Rounding a double value to x number of decimal places in swift

var n = 123.111222333
n = Double(Int(n * 10.0)) / 10.0

Result: n = 123.1

Change 10.0 (1 decimal place) to any of 100.0 (2 decimal place), 1000.0 (3 decimal place) and so on, for the number of digits you want after decimal..

Bootstrap how to get text to vertical align in a div container

h2.text-left{
  position:relative;
  top:50%;
  transform: translateY(-50%);
  -webkit-transform: translateY(-50%);
  -ms-transform: translateY(-50%);
}

Explanation:

The top:50% style essentially pushes the header element down 50% from the top of the parent element. The translateY stylings also act in a similar manner by moving then element down 50% from the top.

Please note that this works well for headers with 1 (maybe 2) lines of text as this simply moves the top of the header element down 50% and then the rest of the content fills in below that, which means that with multiple lines of text it would appear to be slightly below vertically aligned.

A possible fix for multiple lines would be to use a percentage slightly less than 50%.

Regular expression for only characters a-z, A-Z

/^[a-zA-Z]+$/ 

Off the top of my head.

Edit:

Or if you don't like the weird looking literal syntax you can do it like this

new RegExp("^[a-zA-Z]+$");

Script to get the HTTP status code of a list of urls?

This relies on widely available wget, present almost everywhere, even on Alpine Linux.

wget --server-response --spider --quiet "${url}" 2>&1 | awk 'NR==1{print $2}'

The explanations are as follow :

--quiet

Turn off Wget's output.

Source - wget man pages

--spider

[ ... ] it will not download the pages, just check that they are there. [ ... ]

Source - wget man pages

--server-response

Print the headers sent by HTTP servers and responses sent by FTP servers.

Source - wget man pages

What they don't say about --server-response is that those headers output are printed to standard error (sterr), thus the need to redirect to stdin.

The output sent to standard input, we can pipe it to awk to extract the HTTP status code. That code is :

  • the second ($2) non-blank group of characters: {$2}
  • on the very first line of the header: NR==1

And because we want to print it... {print $2}.

wget --server-response --spider --quiet "${url}" 2>&1 | awk 'NR==1{print $2}'

How do I set a ViewModel on a window in XAML using DataContext property?

In addition to the solution that other people provided (which are good, and correct), there is a way to specify the ViewModel in XAML, yet still separate the specific ViewModel from the View. Separating them is useful for when you want to write isolated test cases.

In App.xaml:

<Application
    x:Class="BuildAssistantUI.App"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:BuildAssistantUI.ViewModels"
    StartupUri="MainWindow.xaml"
    >
    <Application.Resources>
        <local:MainViewModel x:Key="MainViewModel" />
    </Application.Resources>
</Application>

In MainWindow.xaml:

<Window x:Class="BuildAssistantUI.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    DataContext="{StaticResource MainViewModel}"
    />

Disable validation of HTML5 form elements

Just use novalidate in your form.

<form name="myForm" role="form" novalidate class="form-horizontal" ng-hide="formMain">

Cheers!!!

How to create custom button in Android using XML Styles

<gradient android:startColor="#ffdd00"
    android:endColor="@color/colorPrimary"
    android:centerColor="#ffff" />

<corners android:radius="33dp"/>

<padding
    android:bottom="7dp"
    android:left="7dp"
    android:right="7dp"
    android:top="7dp"
    />

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

Solution that handles colspan

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

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

Live Demo

JS

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

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

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

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

CSS

.highlight {
  background-color: #EEE;
}

HTML

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

Styling JQuery UI Autocomplete

You can overwrite the classes in your own css using !important, e.g. if you want to get rid of the rounded corners.

.ui-corner-all
{
border-radius: 0px !important;
}

Select rows from a data frame based on values in a vector

Have a look at ?"%in%".

dt[dt$fct %in% vc,]
   fct X
1    a 2
3    c 3
5    c 5
7    a 7
9    c 9
10   a 1
12   c 2
14   c 4

You could also use ?is.element:

dt[is.element(dt$fct, vc),]

CSS rotate property in IE

Usefull Link for IE transform

This tool converts CSS3 Transform properties (which almost all modern browsers use) to the equivalent CSS using Microsoft's proprietary Visual Filters technology.

Updating .class file in jar

Do you want to do it automatically or manually? If manually, a JAR file is really just a ZIP file, so you should be able to open it with any ZIP reader. (You may need to change the extension first.) If you want to update the JAR file automatically via Eclipse, you may want to look into Ant support in Eclipse and look at the zip task.

jQuery preventDefault() not triggered

Try this:

$("div.subtab_left li.notebook a").click(function(e) {
    e.preventDefault();
});

How to ignore deprecation warnings in Python

For python 3, just write below codes to ignore all warnings.

from warnings import filterwarnings
filterwarnings("ignore")

When should an Excel VBA variable be killed or set to Nothing?

VB6/VBA uses deterministic approach to destoying objects. Each object stores number of references to itself. When the number reaches zero, the object is destroyed.

Object variables are guaranteed to be cleaned (set to Nothing) when they go out of scope, this decrements the reference counters in their respective objects. No manual action required.

There are only two cases when you want an explicit cleanup:

  1. When you want an object to be destroyed before its variable goes out of scope (e.g., your procedure is going to take long time to execute, and the object holds a resource, so you want to destroy the object as soon as possible to release the resource).

  2. When you have a circular reference between two or more objects.

    If objectA stores a references to objectB, and objectB stores a reference to objectA, the two objects will never get destroyed unless you brake the chain by explicitly setting objectA.ReferenceToB = Nothing or objectB.ReferenceToA = Nothing.

The code snippet you show is wrong. No manual cleanup is required. It is even harmful to do a manual cleanup, as it gives you a false sense of more correct code.

If you have a variable at a class level, it will be cleaned/destroyed when the class instance is destructed. You can destroy it earlier if you want (see item 1.).

If you have a variable at a module level, it will be cleaned/destroyed when your program exits (or, in case of VBA, when the VBA project is reset). You can destroy it earlier if you want (see item 1.).

Access level of a variable (public vs. private) does not affect its life time.

How to find files modified in last x minutes (find -mmin does not work as expected)

This may work for you. I used it for cleaning folders during deployments for deleting old deployment files.

clean_anyfolder() {
    local temp2="$1/**"; //PATH
    temp3=( $(ls -d $temp2 -t | grep "`date | awk '{print $2" "$3}'`") )
    j=0;
    while [ $j -lt ${#temp3[@]} ]
    do
            echo "to be removed ${temp3[$j]}"
            delete_file_or_folder ${temp3[$j]} 0 //DELETE HERE
        fi
        j=`expr $j + 1`
    done
}

SQL DELETE with JOIN another table for WHERE condition

I think, from your description, the following would suffice:

DELETE FROM guide_category 
WHERE id_guide NOT IN (SELECT id_guide FROM guide)

I assume, that there are no referential integrity constraints on the tables involved, are there?

Cannot open new Jupyter Notebook [Permission Denied]

None of the above worked for me but the below did:

sudo chown -R user: /Library/Frameworks/Python.framework/Versions/3.9/share/jupyter/

Where user is your username.

How to connect to a MySQL Data Source in Visual Studio

Installing the following packages:

adds MySQL Database to the data sources list (Visual Studio 2017)

How can I convert my Java program to an .exe file?

javapackager

The Java Packager tool compiles, packages, and prepares Java and JavaFX applications for distribution. The javapackager command is the command-line version.

– Oracle's documentation

The javapackager utility ships with the JDK. It can generate .exe files with the -native exe flag, among many other things.

WinRun4J

WinRun4j is a java launcher for windows. It is an alternative to javaw.exe and provides the following benefits:

  • Uses an INI file for specifying classpath, main class, vm args, program args.
  • Custom executable name that appears in task manager.
  • Additional JVM args for more flexible memory use.
  • Built-in icon replacer for custom icon.
  • [more bullet points follow]

– WinRun4J's webpage

WinRun4J is an open source utility. It has many features.

packr

Packages your JAR, assets and a JVM for distribution on Windows, Linux and Mac OS X, adding a native executable file to make it appear like a native app. Packr is most suitable for GUI applications.

– packr README

packr is another open source tool.

JSmooth

JSmooth is a Java Executable Wrapper. It creates native Windows launchers (standard .exe) for your java applications. It makes java deployment much smoother and user-friendly, as it is able to find any installed Java VM by itself.

– JSmooth's website

JSmooth is open source and has features, but it is very old. The last release was in 2007.

JexePack

JexePack is a command line tool (great for automated scripting) that allows you to package your Java application (class files), optionally along with its resources (like GIF/JPG/TXT/etc), into a single compressed 32-bit Windows EXE, which runs using Sun's Java Runtime Environment. Both console and windowed applications are supported.

– JexePack's website

JexePack is trialware. Payment is required for production use, and exe files created with this tool will display "reminders" without payment. Also, the last release was in 2013.

InstallAnywhere

InstallAnywhere makes it easy for developers to create professional installation software for any platform. With InstallAnywhere, you’ll adapt to industry changes quickly, get to market faster and deliver an engaging customer experience. And know the vulnerability of your project’s OSS components before you ship.

– InstallAnywhere's website

InstallAnywhere is a commercial/enterprise package that generates installers for Java-based programs. It's probably capable of creating .exe files.

Executable JAR files

As an alternative to .exe files, you can create a JAR file that automatically runs when double-clicked, by adding an entry point to the JAR manifest.


For more information

An excellent source of information on this topic is Excelsior's article "Convert Java to EXE – Why, When, When Not and How".

See also the companion article "Best JAR to EXE Conversion Tools, Free and Commercial".

How do I check if an index exists on a table field in MySQL?

to just look at a tables layout from the cli. you would do

desc mytable

or

show table mytable

'Property does not exist on type 'never'

Because you are assigning instance to null. The compiler infers that it can never be anything other than null. So it assumes that the else block should never be executed so instance is typed as never in the else block.

Now if you don't declare it as the literal value null, and get it by any other means (ex: let instance: Foo | null = getFoo();), you will see that instance will be null inside the if block and Foo inside the else block.

Never type documentation: https://www.typescriptlang.org/docs/handbook/basic-types.html#never

Edit:

The issue in the updated example is actually an open issue with the compiler. See:

https://github.com/Microsoft/TypeScript/issues/11498 https://github.com/Microsoft/TypeScript/issues/12176

How to perform a for-each loop over all the files under a specified path?

Here is a better way to loop over files as it handles spaces and newlines in file names:

#!/bin/bash

find . -type f -iname "*.txt" -print0 | while IFS= read -r -d $'\0' line; do
    echo "$line"
    ls -l "$line"    
done

login failed for user 'sa'. The user is not associated with a trusted SQL Server connection. (Microsoft SQL Server, Error: 18452) in sql 2008

I was stuck in same problem for many hours. I tried everything found on internet.

At last, I figured out a surprising solution : I had missed \SQLEXPRESS part of the Server name: MY-COMPUTER-NAME\SQLEXPRESS

I hope this helps someone who is stuck in similar kind of problem.

DOM element to corresponding vue.js component

Since v-ref is no longer a directive, but a special attribute, it can also be dynamically defined. This is especially useful in combination with v-for.

For example:

<ul>
    <li v-for="(item, key) in items" v-on:click="play(item,$event)">
        <a v-bind:ref="'key' + item.id" v-bind:href="item.url">
            <!-- content -->
        </a>
    </li>
</ul>

and in Vue component you can use

var recordingModel = new Vue({
  el:'#rec-container',
  data:{
    items:[]
  },

  methods:{
    play:function(key,e){
      // it contains the bound reference
      console.log(this.$refs['item'+key]);
    }
  }
});

How to make vim paste from (and copy to) system's clipboard?

If you are on windows and you want to paste contents of system clipboard using p then type this command.

:set clipboard = unnamed

This solved my problem.

In MySQL, can I copy one row to insert into the same table?

Update 07/07/2014 - The answer based on my answer, by Grim..., is a better solution as it improves on my solution below, so I'd suggest using that.

You can do this without listing all the columns with the following syntax:

CREATE TEMPORARY TABLE tmptable SELECT * FROM table WHERE primarykey = 1;
UPDATE tmptable SET primarykey = 2 WHERE primarykey = 1;
INSERT INTO table SELECT * FROM tmptable WHERE primarykey = 2;

You may decide to change the primary key in another way.

jQuery Form Validation before Ajax submit

You need to trigger form validation before checking if it is valid. Field validation runs after you enter data in each field. Form validation is triggered by the submit event but at the document level. So your event handler is being triggered before jquery validates the whole form. But fret not, there's a simple solution to all of this.

You should validate the form:

if ($(this).validate().form()) {
  // do ajax stuff
}

https://jqueryvalidation.org/Validator.form/#validator-form()

How can I combine two commits into one commit?

  1. Checkout your branch and count quantity of all your commits.
  2. Open git bash and write: git rebase -i HEAD~<quantity of your commits> (i.e. git rebase -i HEAD~5)
  3. In opened txt file change pick keyword to squash for all commits, except first commit (which is on the top). For top one change it to reword (which means you will provide a new comment for this commit in the next step) and click SAVE! If in vim, press esc then save by entering wq! and press enter.
  4. Provide Comment.
  5. Open Git and make "Fetch all" to see new changes.

Done

Create a asmx web service in C# using visual studio 2013

on the web site box, you have selected .NETFramework 4.5 and it doesn show, so click there and choose the 3.5...i hope it helps.

How to use Scanner to accept only valid int as input

I see that Character.isDigit perfectly suits the need, since the input will be just one symbol. Of course we don't have any info about this kb object but just in case it's a java.util.Scanner instance, I'd also suggest using java.io.InputStreamReader for command line input. Here's an example:

java.io.BufferedReader reader = new java.io.BufferedReader(new java.io.InputStreamReader(System.in));
try {
  reader.read();
}
catch(Exception e) {
  e.printStackTrace();
}
reader.close();

Log to the base 2 in python

Try this ,

import math
print(math.log(8,2))  # math.log(number,base) 

Forcing anti-aliasing using css: Is this a myth?

Here's a nice way to achieve anti-aliasing:

text-shadow: 0 0 1px rgba(0,0,0,0.3);

Cannot find Microsoft.Office.Interop Visual Studio

If you're using Visual Studio 2015 and you're encountering this problem, you can install MS Office Developer Tools for VS2015 here.

Override and reset CSS style: auto or none don't work

Set min-width: inherit /* Reset the min-width */

Try this. It will work.

SQL Server Output Clause into a scalar variable

Over a year later... if what you need is get the auto generated id of a table, you can just

SELECT @ReportOptionId = SCOPE_IDENTITY()

Otherwise, it seems like you are stuck with using a table.

android.os.FileUriExposedException: file:///storage/emulated/0/test.txt exposed beyond app through Intent.getData()

Try this solution

PUT THESE PERMISSIONS IN MANIFEST

 <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
 <uses-permission android:name="android.permission.CAMERA" />

INTENT TO CAPTURE IMAGE

Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
                    startActivityForResult(takePictureIntent, REQUEST_IMAGE_CAPTURE);
                }

GET CAPTURED IMAGE IN ONACTIVITYRESULT

@Override
            protected void onActivityResult(int requestCode, int resultCode, Intent data) {
                super.onActivityResult(requestCode, resultCode, data);
                if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
                    Bundle extras = data.getExtras();
                    Bitmap imageBitmap = (Bitmap) extras.get("data");
                    // CALL THIS METHOD TO GET THE URI FROM THE BITMAP
                    Uri tempUri = getImageUri(getApplicationContext(), imageBitmap);
                    //DO SOMETHING WITH URI
                }
            } 

METHOD TO GET IMAGE URI

public Uri getImageUri(Context inContext, Bitmap inImage) {
        ByteArrayOutputStream bytes = new ByteArrayOutputStream();
        inImage.compress(Bitmap.CompressFormat.JPEG, 100, bytes);
        String path = MediaStore.Images.Media.insertImage(inContext.getContentResolver(), inImage, "Title", null);
        return Uri.parse(path);
    }

Git push rejected after feature branch rebase

I would use instead "checkout -b" and it is easier to understand.

git checkout myFeature
git rebase master
git push origin --delete myFeature
git push origin myFeature

when you delete you prevent to push in an exiting branch that contains different SHA ID. I am deleting only the remote branch in this case.

Display Image On Text Link Hover CSS Only

It is not possible to do this with just CSS alone, you will need to use Javascript.

<img src="default_image.jpg" id="image" width="100" height="100" alt="" />


<a href="page.html" onmouseover="document.images['image'].src='mouseover.jpg';" onmouseout="document.images['image'].src='default_image.jpg';"/>Text</a>

Proxy with urllib2

proxy = urllib2.ProxyHandler({'http': '127.0.0.1'})
opener = urllib2.build_opener(proxy)
urllib2.install_opener(opener)
urllib2.urlopen('http://www.google.com')

Setting java locale settings

You could call during init or whatever Locale.setDefault() or -Duser.language=, -Duser.country=, and -Duser.variant= at the command line. Here's something on Sun's site.

Retrieve the commit log for a specific line in a file?

Simplifying @matt's answer -

git blame -L14,15 -- <file_path>

Here you will get a blame for a lines 14 to 15.

Since -L option expects Range as a param we can't get a Blame for a single line using the -L option`.

Reference

Declaring and initializing arrays in C

It is not possible to assign values to an array all at once after initialization. The best alternative would be to use a loop.

for(i=0;i<N;i++)
{
     array[i] = i;
}

You can hard code and assign values like --array[0] = 1 and so on.

Memcpy can also be used if you have the data stored in an array already.

Image comparison - fast algorithm

Below are three approaches to solving this problem (and there are many others).

  • The first is a standard approach in computer vision, keypoint matching. This may require some background knowledge to implement, and can be slow.

  • The second method uses only elementary image processing, and is potentially faster than the first approach, and is straightforward to implement. However, what it gains in understandability, it lacks in robustness -- matching fails on scaled, rotated, or discolored images.

  • The third method is both fast and robust, but is potentially the hardest to implement.

Keypoint Matching

Better than picking 100 random points is picking 100 important points. Certain parts of an image have more information than others (particularly at edges and corners), and these are the ones you'll want to use for smart image matching. Google "keypoint extraction" and "keypoint matching" and you'll find quite a few academic papers on the subject. These days, SIFT keypoints are arguably the most popular, since they can match images under different scales, rotations, and lighting. Some SIFT implementations can be found here.

One downside to keypoint matching is the running time of a naive implementation: O(n^2m), where n is the number of keypoints in each image, and m is the number of images in the database. Some clever algorithms might find the closest match faster, like quadtrees or binary space partitioning.


Alternative solution: Histogram method

Another less robust but potentially faster solution is to build feature histograms for each image, and choose the image with the histogram closest to the input image's histogram. I implemented this as an undergrad, and we used 3 color histograms (red, green, and blue), and two texture histograms, direction and scale. I'll give the details below, but I should note that this only worked well for matching images VERY similar to the database images. Re-scaled, rotated, or discolored images can fail with this method, but small changes like cropping won't break the algorithm

Computing the color histograms is straightforward -- just pick the range for your histogram buckets, and for each range, tally the number of pixels with a color in that range. For example, consider the "green" histogram, and suppose we choose 4 buckets for our histogram: 0-63, 64-127, 128-191, and 192-255. Then for each pixel, we look at the green value, and add a tally to the appropriate bucket. When we're done tallying, we divide each bucket total by the number of pixels in the entire image to get a normalized histogram for the green channel.

For the texture direction histogram, we started by performing edge detection on the image. Each edge point has a normal vector pointing in the direction perpendicular to the edge. We quantized the normal vector's angle into one of 6 buckets between 0 and PI (since edges have 180-degree symmetry, we converted angles between -PI and 0 to be between 0 and PI). After tallying up the number of edge points in each direction, we have an un-normalized histogram representing texture direction, which we normalized by dividing each bucket by the total number of edge points in the image.

To compute the texture scale histogram, for each edge point, we measured the distance to the next-closest edge point with the same direction. For example, if edge point A has a direction of 45 degrees, the algorithm walks in that direction until it finds another edge point with a direction of 45 degrees (or within a reasonable deviation). After computing this distance for each edge point, we dump those values into a histogram and normalize it by dividing by the total number of edge points.

Now you have 5 histograms for each image. To compare two images, you take the absolute value of the difference between each histogram bucket, and then sum these values. For example, to compare images A and B, we would compute

|A.green_histogram.bucket_1 - B.green_histogram.bucket_1| 

for each bucket in the green histogram, and repeat for the other histograms, and then sum up all the results. The smaller the result, the better the match. Repeat for all images in the database, and the match with the smallest result wins. You'd probably want to have a threshold, above which the algorithm concludes that no match was found.


Third Choice - Keypoints + Decision Trees

A third approach that is probably much faster than the other two is using semantic texton forests (PDF). This involves extracting simple keypoints and using a collection decision trees to classify the image. This is faster than simple SIFT keypoint matching, because it avoids the costly matching process, and keypoints are much simpler than SIFT, so keypoint extraction is much faster. However, it preserves the SIFT method's invariance to rotation, scale, and lighting, an important feature that the histogram method lacked.

Update:

My mistake -- the Semantic Texton Forests paper isn't specifically about image matching, but rather region labeling. The original paper that does matching is this one: Keypoint Recognition using Randomized Trees. Also, the papers below continue to develop the ideas and represent the state of the art (c. 2010):

Can I call a base class's virtual function if I'm overriding it?

Yes you can call it. C++ syntax for calling parent class function in child class is

class child: public parent {
  // ...

  void methodName() {
    parent::methodName(); // calls Parent class' function
  }
};

Read more about function overriding.

Frontend tool to manage H2 database

There's a shell client built in too which is handy.

java -cp h2*.jar org.h2.tools.Shell

http://opensource-soa.blogspot.com.au/2009/03/how-to-use-h2-shell.html

$ java -cp h2.jar org.h2.tools.Shell -help
Interactive command line tool to access a database using JDBC.
Usage: java org.h2.tools.Shell <options>
Options are case sensitive. Supported options are:
[-help] or [-?]        Print the list of options
[-url "<url>"]         The database URL (jdbc:h2:...)
[-user <user>]         The user name
[-password <pwd>]      The password
[-driver <class>]      The JDBC driver class to use (not required in most cases)
[-sql "<statements>"]  Execute the SQL statements and exit
[-properties "<dir>"]  Load the server properties from this directory
If special characters don't work as expected, you may need to use
 -Dfile.encoding=UTF-8 (Mac OS X) or CP850 (Windows).
See also http://h2database.com/javadoc/org/h2/tools/Shell.html

Calling a Fragment method from a parent Activity

you also call fragment method using interface like

first you create interface

public interface InterfaceName {
    void methodName();
}

after creating interface you implement interface in your fragment

MyFragment extends Fragment implements InterfaceName {
    @overide
    void methodName() {

    }
}

and you create the reference of interface in your activity

class Activityname extends AppCompatActivity {
    Button click;
    MyFragment fragment;

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity);

        click = findViewById(R.id.button);

        fragment = new MyFragment();

        click.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
               fragment.methodName();
            }
        });
    }
}

What are some great online database modeling tools?

S.Lott inserted a comment, but it should be an answer: see the same question.

EDIT

Since it wasn't as obvious as I intended it to be, here follows a verbatim copy of S.Lott's answer in the other question:

I'm a big fan of ARGO UML from Tigris.org. Draws nice pictures using standard UML notation. It does some code generation, but mostly Java classes, which isn't SQL DDL, so that may not be close enough to what you want to do.

You can look at the Data Modelling Tools list and see if anything there is better than Argo UML. Many of the items on this list are free or cheap.

Also, if you're using Eclipse or NetBeans, there are many design plug-ins, some of which may have the features you're looking for.

How to select an element by classname using jqLite?

angualr uses the lighter version of jquery called as jqlite which means it doesnt have all the features of jQuery. here is a reference in angularjs docs about what you can use from jquery. Angular Element docs

In your case you need to find a div with ID or class name. for class name you can use

var elems =$element.find('div') //returns all the div's in the $elements
    angular.forEach(elems,function(v,k)){
    if(angular.element(v).hasClass('class-name')){
     console.log(angular.element(v));
}}

or you can use much simpler way by query selector

angular.element(document.querySelector('#id'))

angular.element(elem.querySelector('.classname'))

it is not as flexible as jQuery but what

Found conflicts between different versions of the same dependent assembly that could not be resolved

I have uninstalled Microsoft ASP.NET MVC nuget.org from manage NuGet Packagaes and again re-installed it. While re-installing it resolved all the conflicts related to razor version. Try it .

How do I create an array of strings in C?

char name[10][10]
int i,j,n;//here "n" is number of enteries
printf("\nEnter size of array = ");
scanf("%d",&n);
for(i=0;i<n;i++)
{
    for(j=0;j<1;j++)
    {
        printf("\nEnter name = ");
        scanf("%s",&name[i]);
    }
}
//printing the data
for(i=0;i<n;i++)
{
    for(j=0;j<1;j++)
    {
        printf("%d\t|\t%s\t|\t%s",rollno[i][j],name[i],sex[i]);
    }
    printf("\n");
}

Here try this!!!

How Can I Truncate A String In jQuery?

The solution above won't work if the original string has no spaces.

Try this:

var title = "This is your title";
var shortText = jQuery.trim(title).substring(0, 10)
                          .trim(this) + "...";

How to load json into my angular.js ng-model?

Here's a simple example of how to load JSON data into an Angular model.

I have a JSON 'GET' web service which returns a list of Customer details, from an online copy of Microsoft's Northwind SQL Server database.

http://www.iNorthwind.com/Service1.svc/getAllCustomers

It returns some JSON data which looks like this:

{ 
    "GetAllCustomersResult" : 
        [
            {
              "CompanyName": "Alfreds Futterkiste",
              "CustomerID": "ALFKI"
            },
            {
              "CompanyName": "Ana Trujillo Emparedados y helados",
              "CustomerID": "ANATR"
            },
            {
              "CompanyName": "Antonio Moreno Taquería",
              "CustomerID": "ANTON"
            }
        ]
    }

..and I want to populate a drop down list with this data, to look like this...

Angular screenshot

I want the text of each item to come from the "CompanyName" field, and the ID to come from the "CustomerID" fields.

How would I do it ?

My Angular controller would look like this:

function MikesAngularController($scope, $http) {

    $scope.listOfCustomers = null;

    $http.get('http://www.iNorthwind.com/Service1.svc/getAllCustomers')
         .success(function (data) {
             $scope.listOfCustomers = data.GetAllCustomersResult;
         })
         .error(function (data, status, headers, config) {
             //  Do some error handling here
         });
}

... which fills a "listOfCustomers" variable with this set of JSON data.

Then, in my HTML page, I'd use this:

<div ng-controller='MikesAngularController'>
    <span>Please select a customer:</span>
    <select ng-model="selectedCustomer" ng-options="customer.CustomerID as customer.CompanyName for customer in listOfCustomers" style="width:350px;"></select>
</div>

And that's it. We can now see a list of our JSON data on a web page, ready to be used.

The key to this is in the "ng-options" tag:

customer.CustomerID as customer.CompanyName for customer in listOfCustomers

It's a strange syntax to get your head around !

When the user selects an item in this list, the "$scope.selectedCustomer" variable will be set to the ID (the CustomerID field) of that Customer record.

The full script for this example can be found here:

JSON data with Angular

Mike

How do I detect IE 8 with jQuery?

It is documented in jQuery API Documentation. Check for Internet Explorer with $.browser.msie and then check its version with $.browser.version.

UPDATE: $.browser removed in jQuery 1.9

The jQuery.browser() method has been deprecated since jQuery 1.3 and is removed in 1.9. If needed, it is available as part of the jQuery Migrate plugin. We recommend using feature detection with a library such as Modernizr.

Timestamp with a millisecond precision: How to save them in MySQL

You need to be at MySQL version 5.6.4 or later to declare columns with fractional-second time datatypes. Not sure you have the right version? Try SELECT NOW(3). If you get an error, you don't have the right version.

For example, DATETIME(3) will give you millisecond resolution in your timestamps, and TIMESTAMP(6) will give you microsecond resolution on a *nix-style timestamp.

Read this: https://dev.mysql.com/doc/refman/8.0/en/fractional-seconds.html

NOW(3) will give you the present time from your MySQL server's operating system with millisecond precision.

If you have a number of milliseconds since the Unix epoch, try this to get a DATETIME(3) value

FROM_UNIXTIME(ms * 0.001)

Javascript timestamps, for example, are represented in milliseconds since the Unix epoch.

(Notice that MySQL internal fractional arithmetic, like * 0.001, is always handled as IEEE754 double precision floating point, so it's unlikely you'll lose precision before the Sun becomes a white dwarf star.)

If you're using an older version of MySQL and you need subsecond time precision, your best path is to upgrade. Anything else will force you into doing messy workarounds.

If, for some reason you can't upgrade, you could consider using BIGINT or DOUBLE columns to store Javascript timestamps as if they were numbers. FROM_UNIXTIME(col * 0.001) will still work OK. If you need the current time to store in such a column, you could use UNIX_TIMESTAMP() * 1000

How can I render repeating React elements?

Since Array(3) will create an un-iterable array, it must be populated to allow the usage of the map Array method. A way to "convert" is to destruct it inside Array-brackets, which "forces" the Array to be filled with undefined values, same as Array(N).fill(undefined)

<table>
    { [...Array(3)].map((_, index) => <tr key={index}/>) }
</table>

Another way would be via Array fill():

<table>
    { Array(3).fill(<tr/>) }
</table>

?? Problem with above example is the lack of key prop, which is a must.
(Using an iterator's index as key is not recommended)


Nested Nodes:

_x000D_
_x000D_
const tableSize = [3,4]
const Table = (
    <table>
        <tbody>
        { [...Array(tableSize[0])].map((tr, trIdx) => 
            <tr key={trIdx}> 
              { [...Array(tableSize[1])].map((a, tdIdx, arr) => 
                  <td key={trIdx + tdIdx}>
                  {arr.length * trIdx + tdIdx + 1}
                  </td>
               )}
            </tr>
        )}
        </tbody>
    </table>
);

ReactDOM.render(Table, document.querySelector('main'))
_x000D_
td{ border:1px solid silver; padding:1em; }
_x000D_
<script crossorigin src="https://unpkg.com/react@16/umd/react.development.js"></script>
<script crossorigin src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"></script>
<main></main>
_x000D_
_x000D_
_x000D_

shorthand If Statements: C#

Use the ternary operator

direction == 1 ? dosomething () : dosomethingelse ();

Extract the filename from a path

Find a file using wildcard and getting filename:

Resolve-Path "Package.1.0.191.*.zip" | Split-Path -leaf

How to get a URL parameter in Express?

If you want to grab the query parameter value in the URL, follow below code pieces

//url.localhost:8888/p?tagid=1234
req.query.tagid
OR
req.param.tagid

If you want to grab the URL parameter using Express param function

Express param function to grab a specific parameter. This is considered middleware and will run before the route is called.

This can be used for validations or grabbing important information about item.

An example for this would be:

// parameter middleware that will run before the next routes
app.param('tagid', function(req, res, next, tagid) {

// check if the tagid exists
// do some validations
// add something to the tagid
var modified = tagid+ '123';

// save name to the request
req.tagid= modified;

next();
});

// http://localhost:8080/api/tags/98
app.get('/api/tags/:tagid', function(req, res) {
// the tagid was found and is available in req.tagid
res.send('New tag id ' + req.tagid+ '!');
});

Delete directory with files in it?

you can try this simple 12 line of code for delete folder or folder files... happy coding... ;) :)

function deleteAll($str) {
    if (is_file($str)) {
        return unlink($str);
    }
    elseif (is_dir($str)) {
        $scan = glob(rtrim($str,'/').'/*');
        foreach($scan as $index=>$path) {
            $this->deleteAll($path);
        }            
        return @rmdir($str);
    }
}

curl -GET and -X GET

By default you use curl without explicitly saying which request method to use. If you just pass in a HTTP URL like curl http://example.com it will use GET. If you use -d or -F curl will use POST, -I will cause a HEAD and -T will make it a PUT.

If for whatever reason you're not happy with these default choices that curl does for you, you can override those request methods by specifying -X [WHATEVER]. This way you can for example send a DELETE by doing curl -X DELETE [URL].

It is thus pointless to do curl -X GET [URL] as GET would be used anyway. In the same vein it is pointless to do curl -X POST -d data [URL]... But you can make a fun and somewhat rare request that sends a request-body in a GET request with something like curl -X GET -d data [URL].

Digging deeper

curl -GET (using a single dash) is just wrong for this purpose. That's the equivalent of specifying the -G, -E and -T options and that will do something completely different.

There's also a curl option called --get to not confuse matters with either. It is the long form of -G, which is used to convert data specified with -d into a GET request instead of a POST.

(I subsequently used my own answer here to populate the curl FAQ to cover this.)

Warnings

Modern versions of curl will inform users about this unnecessary and potentially harmful use of -X when verbose mode is enabled (-v) - to make users aware. Further explained and motivated in this blog post.

-G converts a POST + body to a GET + query

You can ask curl to convert a set of -d options and instead of sending them in the request body with POST, put them at the end of the URL's query string and issue a GET, with the use of `-G. Like this:

curl -d name=daniel -d grumpy=yes -G https://example.com/

Extracting specific columns from a data frame

[ and subset are not substitutable:

[ does return a vector if only one column is selected.

df = data.frame(a="a",b="b")    

identical(
  df[,c("a")], 
  subset(df,select="a")
) 

identical(
  df[,c("a","b")],  
  subset(df,select=c("a","b"))
)

Java Regex Capturing Groups

The issue you're having is with the type of quantifier. You're using a greedy quantifier in your first group (index 1 - index 0 represents the whole Pattern), which means it'll match as much as it can (and since it's any character, it'll match as many characters as there are in order to fulfill the condition for the next groups).

In short, your 1st group .* matches anything as long as the next group \\d+ can match something (in this case, the last digit).

As per the 3rd group, it will match anything after the last digit.

If you change it to a reluctant quantifier in your 1st group, you'll get the result I suppose you are expecting, that is, the 3000 part.

Note the question mark in the 1st group.

String line = "This order was placed for QT3000! OK?";
Pattern pattern = Pattern.compile("(.*?)(\\d+)(.*)");
Matcher matcher = pattern.matcher(line);
while (matcher.find()) {
    System.out.println("group 1: " + matcher.group(1));
    System.out.println("group 2: " + matcher.group(2));
    System.out.println("group 3: " + matcher.group(3));
}

Output:

group 1: This order was placed for QT
group 2: 3000
group 3: ! OK?

More info on Java Pattern here.

Finally, the capturing groups are delimited by round brackets, and provide a very useful way to use back-references (amongst other things), once your Pattern is matched to the input.

In Java 6 groups can only be referenced by their order (beware of nested groups and the subtlety of ordering).

In Java 7 it's much easier, as you can use named groups.

How to get primary key of table?

MySQL has a SQL query "SHOW INDEX FROM" which returns the indexes from a table. For eg. - the following query will show all the indexes for the products table:-

SHOW INDEXES FROM products \G

It returns a table with type, column_name, Key_name, etc. and displays output with all indexes and primary keys as -

*************************** 1. row ***************************
        Table: products
   Non_unique: 0
     Key_name: PRIMARY
 Seq_in_index: 1
  Column_name: product_id
    Collation: A
  Cardinality: 0
     Sub_part: NULL
       Packed: NULL
         Null: 
   Index_type: BTREE
      Comment: 
Index_comment: 

To just display primary key from the table use :-

SHOW INDEXES FROM table_name WHERE Key_name = 'PRIMARY'

Java, List only subdirectories from a directory, not files

    File files = new File("src");
    // src is folder name...
    //This will return the list of the subDirectories
    List<File> subDirectories = Arrays.stream(files.listFiles()).filter(File::isDirectory).collect(Collectors.toList());
// this will print all the sub directories
Arrays.stream(files.listFiles()).filter(File::isDirectory).forEach(System.out::println);

MySQL - SELECT all columns WHERE one column is DISTINCT

If what your asking is to only show rows that have 1 link for them then you can use the following:

SELECT * FROM posted WHERE link NOT IN 
(SELECT link FROM posted GROUP BY link HAVING COUNT(LINK) > 1)

Again this is assuming that you want to cut out anything that has a duplicate link.

offsetTop vs. jQuery.offset().top

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

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

Convert A String (like testing123) To Binary In Java

A shorter example

private static final Charset UTF_8 = Charset.forName("UTF-8");

String text = "Hello World!";
byte[] bytes = text.getBytes(UTF_8);
System.out.println("bytes= "+Arrays.toString(bytes));
System.out.println("text again= "+new String(bytes, UTF_8));

prints

bytes= [72, 101, 108, 108, 111, 32, 87, 111, 114, 108, 100, 33]
text again= Hello World!

Binding ComboBox SelectedItem using MVVM

I had a similar problem where the SelectedItem-binding did not update when I selected something in the combobox. My problem was that I had to set UpdateSourceTrigger=PropertyChanged for the binding.

<ComboBox ItemsSource="{Binding SalesPeriods}" 
          SelectedItem="{Binding SelectedItem, UpdateSourceTrigger=PropertyChanged}" />

Which version of Python do I have installed?

For bash scripts this would be the easiest way:

# In the form major.minor.micro e.g. '3.6.8'
# The second part excludes the 'Python ' prefix 
PYTHON_VERSION=`python3 --version | awk '{print $2}'`
echo "python3 version: ${PYTHON_VERSION}"
python3 version: 3.6.8

And if you just need the major.minor version (e.g. 3.6) you can either use the above and then pick the first 3 characters:

PYTHON_VERSION=`python3 --version | awk '{print $2}'`
echo "python3 major.minor: ${PYTHON_VERSION:0:3}"
python3 major.minor: 3.6

or

PYTHON_VERSION=`python3 -c 'import sys; print(str(sys.version_info[0])+"."+str(sys.version_info[1]))'`
echo "python3 major.minor: ${PYTHON_VERSION}"
python3 major.minor: 3.6

How can I replace every occurrence of a String in a file with PowerShell?

(Get-Content file.txt) | 
Foreach-Object {$_ -replace '\[MYID\]','MyValue'}  | 
Out-File file.txt

Note the parentheses around (Get-Content file.txt) is required:

Without the parenthesis the content is read, one line at a time, and flows down the pipeline until it reaches out-file or set-content, which tries to write to the same file, but it's already open by get-content and you get an error. The parenthesis causes the operation of content reading to be performed once (open, read and close). Only then when all lines have been read, they are piped one at a time and when they reach the last command in the pipeline they can be written to the file. It's the same as $content=content; $content | where ...

What does @media screen and (max-width: 1024px) mean in CSS?

It means if the screen size is 1024 then only apply below CSS rules.

How do I calculate the MD5 checksum of a file in Python?

You can calculate the checksum of a file by reading the binary data and using hashlib.md5().hexdigest(). A function to do this would look like the following:

def File_Checksum_Dis(dirname):
    
    if not os.path.exists(dirname):
        print(dirname+" directory is not existing");
    
    for fname in os.listdir(dirname):
        if not fname.endswith('~'):
            fnaav = os.path.join(dirname, fname);
            fd = open(fnaav, 'rb');
            data = fd.read();
            fd.close();
        
            print("-"*70);
            print("File Name is: ",fname);          
            print(hashlib.md5(data).hexdigest())
            print("-"*70);
                

Dump a list in a pickle file and retrieve it back later

Pickling will serialize your list (convert it, and it's entries to a unique byte string), so you can save it to disk. You can also use pickle to retrieve your original list, loading from the saved file.

So, first build a list, then use pickle.dump to send it to a file...

Python 3.4.1 (default, May 21 2014, 12:39:51) 
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.2.79)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> mylist = ['I wish to complain about this parrot what I purchased not half an hour ago from this very boutique.', "Oh yes, the, uh, the Norwegian Blue...What's,uh...What's wrong with it?", "I'll tell you what's wrong with it, my lad. 'E's dead, that's what's wrong with it!", "No, no, 'e's uh,...he's resting."]
>>> 
>>> import pickle
>>> 
>>> with open('parrot.pkl', 'wb') as f:
...   pickle.dump(mylist, f)
... 
>>> 

Then quit and come back later… and open with pickle.load...

Python 3.4.1 (default, May 21 2014, 12:39:51) 
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.2.79)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import pickle
>>> with open('parrot.pkl', 'rb') as f:
...   mynewlist = pickle.load(f)
... 
>>> mynewlist
['I wish to complain about this parrot what I purchased not half an hour ago from this very boutique.', "Oh yes, the, uh, the Norwegian Blue...What's,uh...What's wrong with it?", "I'll tell you what's wrong with it, my lad. 'E's dead, that's what's wrong with it!", "No, no, 'e's uh,...he's resting."]
>>>

Could not load file or assembly ... An attempt was made to load a program with an incorrect format (System.BadImageFormatException)

I had the same issue. Project B in my case was a .Net Core Class Library which has a Nuget "Microsoft.Management.Infrastructure" installed. The error was that i called my project B "MI". I changed the project name to something else and suddenly everything worked again.

Creating a pandas DataFrame from columns of other DataFrames with similar indexes

What you ask for is the join operation. With the how argument, you can define how unique indices are handled. Here, some article, which looks helpful concerning this point. In the example below, I left out cosmetics (like renaming columns) for simplicity.

Code

import numpy as np
import pandas as pd
df1 = pd.DataFrame(np.random.randn(5,3), index=pd.date_range('01/02/2014',periods=5,freq='D'), columns=['a','b','c'] )
df2 = pd.DataFrame(np.random.randn(8,3), index=pd.date_range('01/01/2014',periods=8,freq='D'), columns=['a','b','c'] )

df3 = df1.join(df2, how='outer', lsuffix='_df1', rsuffix='_df2')
print(df3)

Output

               a_df1     b_df1     c_df1     a_df2     b_df2     c_df2
2014-01-01       NaN       NaN       NaN  0.109898  1.107033 -1.045376
2014-01-02  0.573754  0.169476 -0.580504 -0.664921 -0.364891 -1.215334
2014-01-03 -0.766361 -0.739894 -1.096252  0.962381 -0.860382 -0.703269
2014-01-04  0.083959 -0.123795 -1.405974  1.825832 -0.580343  0.923202
2014-01-05  1.019080 -0.086650  0.126950 -0.021402 -1.686640  0.870779
2014-01-06 -1.036227 -1.103963 -0.821523 -0.943848 -0.905348  0.430739
2014-01-07       NaN       NaN       NaN  0.312005  0.586585  1.531492
2014-01-08       NaN       NaN       NaN -0.077951 -1.189960  0.995123

Could not autowire field in spring. why?

I've faced the same issue today. Turned out to be I forgot to mention @Service/@Component annotation for my service implementation file, for which spring is not able autowire and failing to create the bean.

How to check if the user can go back in browser history or not

I'm not sure if this works and it is completely untested, but try this:

<script type="text/javascript">

    function goBack() {
        history.back();
    }

    if (history.length > 0) { //if there is a history...
        document.getElementsByTagName('button')[].onclick="goBack()"; //assign function "goBack()" to all buttons onClick
    } else {
        die();
    }
</script>

And somewhere in HTML:

<button value="Button1"> //These buttons have no action
<button value="Button2">

EDIT:

What you can also do is to research what browsers support the back function (I think they all do) and use the standard JavaScript browser detection object found, and described thoroughly, on this page. Then you can have 2 different pages: one for the "good browsers" compatible with the back button and one for the "bad browsers" telling them to go update their browser

How to fill in proxy information in cntlm config file?

Once you generated the file, and changed your password, you can run as below,

cntlm -H

Username will be the same. it will ask for password, give it, then copy the PassNTLMv2, edit the cntlm.ini, then just run the following

cntlm -v

Spark Dataframe distinguish columns with duplicated name

I would recommend that you change the column names for your join.

df1.select(col("a") as "df1_a", col("f") as "df1_f")
   .join(df2.select(col("a") as "df2_a", col("f") as "df2_f"), col("df1_a" === col("df2_a"))

The resulting DataFrame will have schema

(df1_a, df1_f, df2_a, df2_f)

Composer Update Laravel

When you run composer update, composer generates a file called composer.lock which lists all your packages and the currently installed versions. This allows you to later run composer install, which will install the packages listed in that file, recreating the environment that you were last using.

It appears from your log that some of the versions of packages that are listed in your composer.lock file are no longer available. Thus, when you run composer install, it complains and fails. This is usually no big deal - just run composer update and it will attempt to build a set of packages that work together and write a new composer.lock file.

However, you're running into a different problem. It appears that, in your composer.json file, the original developer has added some pre- or post- update actions that are failing, specifically a php artisan migrate command. This can be avoided by running the following: composer update --no-scripts

This will run the composer update but will skip over the scripts added to the file. You should be able to successfully run the update this way.

However, this does not solve the problem long-term. There are two problems:

  1. A migration is for database changes, not random stuff like compiling assets. Go through the migrations and remove that code from there.

  2. Assets should not be compiled each time you run composer update. Remove that step from the composer.json file.

From what I've read, best practice seems to be compiling assets on an as-needed basis during development (ie. when you're making changes to your LESS files - ideally using a tool like gulp.js) and before deployment.

How do you test that a Python function throws an exception?

I just discovered that the Mock library provides an assertRaisesWithMessage() method (in its unittest.TestCase subclass), which will check not only that the expected exception is raised, but also that it is raised with the expected message:

from testcase import TestCase

import mymod

class MyTestCase(TestCase):
    def test1(self):
        self.assertRaisesWithMessage(SomeCoolException,
                                     'expected message',
                                     mymod.myfunc)

Asp.Net MVC with Drop Down List, and SelectListItem Assistance

You have a view model to which your view is strongly typed => use strongly typed helpers:

<%= Html.DropDownListFor(
    x => x.SelectedAccountId, 
    new SelectList(Model.Accounts, "Value", "Text")
) %>

Also notice that I use a SelectList for the second argument.

And in your controller action you were returning the view model passed as argument and not the one you constructed inside the action which had the Accounts property correctly setup so this could be problematic. I've cleaned it a bit:

public ActionResult AccountTransaction()
{
    var accounts = Services.AccountServices.GetAccounts(false);
    var viewModel = new AccountTransactionView
    {
        Accounts = accounts.Select(a => new SelectListItem
        {
            Text = a.Description,
            Value = a.AccountId.ToString()
        })
    };
    return View(viewModel);
}

comparing strings in vb

I think this String.Equals is what you need.

Dim aaa = "12/31"
            Dim a = String.Equals(aaa, "06/30")

a will return false.

Using scanner.nextLine()

or

int selection = Integer.parseInt(scanner.nextLine());

Is there a way to get the git root directory in one command?

If you're looking for a good alias to do this plus not blow up cd if you aren't in a git dir:

alias ..g='git rev-parse && cd "$(git rev-parse --show-cdup)"'

When should I use curly braces for ES6 import?

Summary ES6 modules:

Exports:

You have two types of exports:

  1. Named exports
  2. Default exports, a maximum one per module

Syntax:

// Module A
export const importantData_1 = 1;
export const importantData_2 = 2;
export default function foo () {}

Imports:

The type of export (i.e., named or default exports) affects how to import something:

  1. For a named export we have to use curly braces and the exact name as the declaration (i.e. variable, function, or class) which was exported.
  2. For a default export we can choose the name.

Syntax:

// Module B, imports from module A which is located in the same directory

import { importantData_1 , importantData_2  } from './A';  // For our named imports

// Syntax single named import:
// import { importantData_1 }

// For our default export (foo), the name choice is arbitrary
import ourFunction from './A';

Things of interest:

  1. Use a comma-separated list within curly braces with the matching name of the export for named export.
  2. Use a name of your choosing without curly braces for a default export.

Aliases:

Whenever you want to rename a named import this is possible via aliases. The syntax for this is the following:

import { importantData_1 as myData } from './A';

Now we have imported importantData_1, but the identifier is myData instead of importantData_1.

How to copy Java Collections list

Every other Object not --> you need to iterate and do a copy by yourself.

To avoid this implement Cloneable.

public class User implements Serializable, Cloneable {

    private static final long serialVersionUID = 1L;

    private String user;
    private String password;
    ...

    @Override
    public Object clone() {
        Object o = null;
        try {
          o = super.clone();
        } catch(CloneNotSupportedException e) {
        }
        return o;
     }
 }

....

  public static void main(String[] args) {

      List<User> userList1 = new ArrayList<User>();

      User user1 = new User();
      user1.setUser("User1");
      user1.setPassword("pass1");
      ...

      User user2 = new User();
      user2.setUser("User2");
      user2.setPassword("pass2");
      ...

      userList1 .add(user1);
      userList1 .add(user2);

      List<User> userList2 = new ArrayList<User>();


      for(User u: userList1){
          u.add((User)u.clone());
      }

      //With this you can avoid 
      /*
        for(User u: userList1){
            User tmp = new User();
            tmp.setUser(u.getUser);
            tmp.setPassword(u.getPassword);
            ...
            u.add(tmp);               
        }
       */

  }

How do I compile a Visual Studio project from the command-line?

To be honest I have to add my 2 cents.

You can do it with msbuild.exe. There are many version of the msbuild.exe.

C:\Windows\Microsoft.NET\Framework64\v2.0.50727\msbuild.exe C:\Windows\Microsoft.NET\Framework64\v3.5\msbuild.exe C:\Windows\Microsoft.NET\Framework64\v4.0.30319\msbuild.exe
C:\Windows\Microsoft.NET\Framework\v2.0.50727\msbuild.exe C:\Windows\Microsoft.NET\Framework\v3.5\msbuild.exe C:\Windows\Microsoft.NET\Framework\v4.0.30319\msbuild.exe

Use version you need. Basically you have to use the last one.

C:\Windows\Microsoft.NET\Framework64\v4.0.30319\msbuild.exe

So how to do it.

  1. Run the COMMAND window

  2. Input the path to msbuild.exe

C:\Windows\Microsoft.NET\Framework64\v4.0.30319\msbuild.exe

  1. Input the path to the project solution like

"C:\Users\Clark.Kent\Documents\visual studio 2012\Projects\WpfApplication1\WpfApplication1.sln"

  1. Add any flags you need after the solution path.

  2. Press ENTER

Note you can get help about all possible flags like

C:\Windows\Microsoft.NET\Framework64\v4.0.30319\msbuild.exe /help

css3 text-shadow in IE9

I was looking for a cross-browser text-stroke solution that works when overlaid on background images. think I have a solution for this that doesn't involve extra mark-up, js and works in IE7-9 (I haven't tested 6), and doesn't cause aliasing problems.

This is a combination of using CSS3 text-shadow, which has good support except IE (http://caniuse.com/#search=text-shadow), then using a combination of filters for IE. CSS3 text-stroke support is poor at the moment.

IE Filters

The glow filter (http://www.impressivewebs.com/css3-text-shadow-ie/) looks terrible, so I didn't use that.

David Hewitt's answer involved adding dropshadow filters in a combination of directions. ClearType is then removed unfortunately so we end up with badly aliased text.

I then combined some of the elements suggested on useragentman with the dropshadow filters.

Putting it together

This example would be black text with a white stroke. I'm using conditional html classes by the way to target IE (http://paulirish.com/2008/conditional-stylesheets-vs-css-hacks-answer-neither/).

#myelement {
    color: #000000;
    text-shadow:
    -1px -1px 0 #ffffff,  
    1px -1px 0 #ffffff,
    -1px 1px 0 #ffffff,
    1px 1px 0 #ffffff;
}

html.ie7 #myelement,
html.ie8 #myelement,
html.ie9 #myelement {
    background-color: white;
    filter: progid:DXImageTransform.Microsoft.Chroma(color='white') progid:DXImageTransform.Microsoft.Alpha(opacity=100) progid:DXImageTransform.Microsoft.dropshadow(color=#ffffff,offX=1,offY=1) progid:DXImageTransform.Microsoft.dropshadow(color=#ffffff,offX=-1,offY=1) progid:DXImageTransform.Microsoft.dropshadow(color=#ffffff,offX=1,offY=-1) progid:DXImageTransform.Microsoft.dropshadow(color=#ffffff,offX=-1,offY=-1);
    zoom: 1;
}

Html attributes for EditorFor() in ASP.NET MVC

Now ASP.Net MVC 5.1 got a built in support for it.

From Release Notes

We now allow passing in HTML attributes in EditorFor as an anonymous object.

For example:

@Html.EditorFor(model => model, 
              new { htmlAttributes = new { @class = "form-control" }, })

Best way to create a temp table with same columns and type as a permanent table

I realize this question is extremely old, but for anyone looking for a solution specific to PostgreSQL, it's:

CREATE TEMP TABLE tmp_table AS SELECT * FROM original_table LIMIT 0;

Note, the temp table will be put into a schema like pg_temp_3.

This will create a temporary table that will have all of the columns (without indexes) and without the data, however depending on your needs, you may want to then delete the primary key:

ALTER TABLE pg_temp_3.tmp_table DROP COLUMN primary_key;

If the original table doesn't have any data in it to begin with, you can leave off the "LIMIT 0".

Pass data to layout that are common to all pages

Why hasn't anyone suggested extension methods on ViewData?

Option #1

Seems to me by far the least intrusive and simplest solution to the problem. No hardcoded strings. No imposed restrictions. No magic coding. No complex code.

public static class ViewDataExtensions
{
    private const string TitleData = "Title";
    public static void SetTitle<T>(this ViewDataDictionary<T> viewData, string value) => viewData[TitleData] = value;
    public static string GetTitle<T>(this ViewDataDictionary<T> viewData) => (string)viewData[TitleData] ?? "";
}

Set data in the page

ViewData.SetTitle("abc");

Option #2

Another option, making the field declaration easier.

public static class ViewDataExtensions
{
    public static ViewDataField<string, V> Title<V>(this ViewDataDictionary<V> viewData) => new ViewDataField<string, V>(viewData, "Title", "");
}

public class ViewDataField<T,V>
{
    private readonly ViewDataDictionary<V> _viewData;
    private readonly string _field;
    private readonly T _defaultValue;

    public ViewDataField(ViewDataDictionary<V> viewData, string field, T defaultValue)
    {
        _viewData = viewData;
        _field = field;
        _defaultValue = defaultValue;
    }

    public T Value {
        get => (T)(_viewData[_field] ?? _defaultValue);
        set => _viewData[_field] = value;
    }
}

Set data in the page. Declaration is easier than first option, but usage syntax is slightly longer.

ViewData.Title().Value = "abc";

Option #3

Then can combine that with returning a single object containing all layout-related fields with their default values.

public static class ViewDataExtensions
{
    private const string LayoutField = "Layout";
    public static LayoutData Layout<T>(this ViewDataDictionary<T> viewData) => 
        (LayoutData)(viewData[LayoutField] ?? (viewData[LayoutField] = new LayoutData()));
}

public class LayoutData
{
    public string Title { get; set; } = "";
}

Set data in the page

var layout = ViewData.Layout();
layout.Title = "abc";

This third option has several benefits and I think is the best option in most cases:

  • Simplest declaration of fields and default values.

  • Simplest usage syntax when setting multiple fields.

  • Allows setting various kinds of data in the ViewData (eg. Layout, Header, Navigation).

  • Allows additional code and logic within LayoutData class.

P.S. Don't forget to add the namespace of ViewDataExtensions in _ViewImports.cshtml

Which way is best for creating an object in JavaScript? Is `var` necessary before an object property?

There is no "best way" to create an object. Each way has benefits depending on your use case.

The constructor pattern (a function paired with the new operator to invoke it) provides the possibility of using prototypal inheritance, whereas the other ways don't. So if you want prototypal inheritance, then a constructor function is a fine way to go.

However, if you want prototypal inheritance, you may as well use Object.create, which makes the inheritance more obvious.

Creating an object literal (ex: var obj = {foo: "bar"};) works great if you happen to have all the properties you wish to set on hand at creation time.

For setting properties later, the NewObject.property1 syntax is generally preferable to NewObject['property1'] if you know the property name. But the latter is useful when you don't actually have the property's name ahead of time (ex: NewObject[someStringVar]).

Hope this helps!

How do I check out an SVN project into Eclipse as a Java project?

Here are the steps:

  • Install the subclipse plugin (provides svn connectivity in eclipse) and connect to the repository. Instructions here: http://subclipse.tigris.org/install.html
  • Go to File->New->Other->Under the SVN category, select Checkout Projects from SVN.
  • Select your project's root folder and select checkout as a project in the workspace.

It seems you are checking the .project file into the source repository. I would suggest not checking in the .project file so users can have their own version of the file. Also, if you use the subclipse plugin it allows you to check out and configure a source folder as a java project. This process creates the correct .project for you(with the java nature),

android - listview get item view by position

workignHoursListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> parent,View view, int position, long id) {
        viewtype yourview=yourListViewId.getChildAt(position).findViewById(R.id.viewid);
    }
});

REST, HTTP DELETE and parameters

I think this is non-restful. I do not think the restful service should handle the requirement of forcing the user to confirm a delete. I would handle this in the UI.

Does specifying force_delete=true make sense if this were a program's API? If someone was writing a script to delete this resource, would you want to force them to specify force_delete=true to actually delete the resource?

The target principal name is incorrect. Cannot generate SSPI context

I had this problem when trying to connect to my SQL Server 2017 instance via L2TP VPN on a domain-joined Windows 10 machine.

The problem ended up being in my VPN settings. In the security settings, in Authentication, using EAP-MSCHAPv2 and in the Properties dialog, I had selected Automatically use my Windows logon name and password (and domain if any).

Location of the option to turn off

I turned this off and then re-connected my VPN and then I was able to connect to SQL Server successfully.

I believe this was causing my SQL login (with Windows account security) to use Kerberos instead of NTLM, causing the SSPI error.

Java serialization - java.io.InvalidClassException local class incompatible

@DanielChapman gives a good explanation of serialVersionUID, but no solution. the solution is this: run the serialver program on all your old classes. put these serialVersionUID values in your current versions of the classes. as long as the current classes are serial compatible with the old versions, you should be fine. (note for future code: you should always have a serialVersionUID on all Serializable classes)

if the new versions are not serial compatible, then you need to do some magic with a custom readObject implementation (you would only need a custom writeObject if you were trying to write new class data which would be compatible with old code). generally speaking adding or removing class fields does not make a class serial incompatible. changing the type of existing fields usually will.

Of course, even if the new class is serial compatible, you may still want a custom readObject implementation. you may want this if you want to fill in any new fields which are missing from data saved from old versions of the class (e.g. you have a new List field which you want to initialize to an empty list when loading old class data).

how to evenly distribute elements in a div next to each other?

_x000D_
_x000D_
.container {_x000D_
  padding: 10px;_x000D_
}_x000D_
.parent {_x000D_
  width: 100%;_x000D_
  background: #7b7b7b;_x000D_
  display: flex;_x000D_
  justify-content: space-between;_x000D_
  height: 4px;_x000D_
}_x000D_
.child {_x000D_
  color: #fff;_x000D_
  background: green;_x000D_
  padding: 10px 10px;_x000D_
  border-radius: 50%;_x000D_
  position: relative;_x000D_
  top: -8px;_x000D_
}
_x000D_
<div class="container">_x000D_
  <div class="parent">_x000D_
    <span class="child"></span>_x000D_
    <span class="child"></span>_x000D_
    <span class="child"></span>_x000D_
    <span class="child"></span>_x000D_
    <span class="child"></span>_x000D_
    <span class="child"></span>_x000D_
    <span class="child"></span>_x000D_
    <span class="child"></span>_x000D_
    <span class="child"></span>_x000D_
    <span class="child"></span>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How to convert a string of numbers to an array of numbers?

My 2 cents for golfers:

b="1,2,3,4".split`,`.map(x=>+x)

backquote is string litteral so we can omit the parenthesis (because of the nature of split function) but it is equivalent to split(','). The string is now an array, we just have to map each value with a function returning the integer of the string so x=>+x (which is even shorter than the Number function (5 chars instead of 6)) is equivalent to :

function(x){return parseInt(x,10)}// version from techfoobar
(x)=>{return parseInt(x)}         // lambda are shorter and parseInt default is 10
(x)=>{return +x}                  // diff. with parseInt in SO but + is better in this case
x=>+x                             // no multiple args, just 1 function call

I hope it is a bit more clear.

Android Button setOnClickListener Design

Android lambada solution

public void registerButtons(){
    register(R.id.buttonName1, ()-> {/*Your code goes here*/});
    register(R.id.buttonName2, ()-> {/*Your code goes here*/});
    register(R.id.buttonName3, ()-> {/*Your code goes here*/});
}

private void register(int buttonResourceId, Runnable r){
    findViewById(buttonResourceId).setOnClickListener(v -> r.run());
}

Switch case solution solution

public void registerButtons(){
    register(R.id.buttonName1);
    register(R.id.buttonName2);
    register(R.id.buttonName3);
}

private void register(int buttonResourceId){
    findViewById(buttonResourceId).setOnClickListener(buttonClickListener);
}

private OnClickListener buttonClickListener = new OnClickListener() {

    @Override
    public void onClick(View v){
        switch (v.getId()) {
            case R.id.buttonName1:
                // TODO Auto-generated method stub
                break;
            case R.id.buttonName2:
                // TODO Auto-generated method stub
                break;
            case View.NO_ID:
            default:
                // TODO Auto-generated method stub
                break;
        }
    }
};

How do I connect to my existing Git repository using Visual Studio Code?

  1. Open Visual Studio Code terminal (Ctrl + `)
  2. Write the Git clone command. For example,

    git clone https://github.com/angular/angular-phonecat.git
    
  3. Open the folder you have just cloned (menu FileOpen Folder)

    Enter image description here

PHP simple foreach loop with HTML

This will work although when embedding PHP in HTML it is better practice to use the following form:

<table>
    <?php foreach($array as $key=>$value): ?>
    <tr>
        <td><?= $key; ?></td>
    </tr>
    <?php endforeach; ?>
</table>

You can find the doc for the alternative syntax on PHP.net

Where to find free public Web Services?

Here you can find some public REST services for encryption and security related things: http://security.jelastic.servint.net

JSF(Primefaces) ajax update of several elements by ID's

If the to-be-updated component is not inside the same NamingContainer component (ui:repeat, h:form, h:dataTable, etc), then you need to specify the "absolute" client ID. Prefix with : (the default NamingContainer separator character) to start from root.

<p:ajax process="@this" update="count :subTotal"/>

To be sure, check the client ID of the subTotal component in the generated HTML for the actual value. If it's inside for example a h:form as well, then it's prefixed with its client ID as well and you would need to fix it accordingly.

<p:ajax process="@this" update="count :formId:subTotal"/>

Space separation of IDs is more recommended as <f:ajax> doesn't support comma separation and starters would otherwise get confused.

How to listen for 'props' changes

I use props and variables computed properties if I need create logic after to receive the changes

export default {
name: 'getObjectDetail',
filters: {},
components: {},
props: {
    objectDetail: {
      type: Object,
      required: true
    }
},
computed: {
    _objectDetail: {
        let value = false
        ...

        if (someValidation)
        ...
    }
}

Could not find the main class, program will exit

if you build the source files with lower version of Java (example Java1.5) and trying to run that program/application with higher version of Java (example java 1.6) you will get this problem. for better explanation see this link. click here