Programs & Examples On #Coldfire

Common sources of unterminated string literal

Scan the code that comes before the line# mentioned by error message. Whatever is unterminated has resulted in something downstream, (the blamed line#), to be flagged.

Center icon in a div - horizontally and vertically

Since they are already inline-block child elements, you can set text-align:center on the parent without having to set a width or margin:0px auto on the child. Meaning it will work for dynamically generated content with varying widths.

.img_container, .img_container2 {
    text-align: center;
}

This will center the child within both div containers.

UPDATE:

For vertical centering, you can use the calc() function assuming the height of the icon is known.

.img_container > i, .img_container2 > i {
    position:relative;
    top: calc(50% - 10px); /* 50% - 3/4 of icon height */
}

jsFiddle demo - it works.

For what it's worth - you can also use vertical-align:middle assuming display:table-cell is set on the parent.

inline if statement java, why is not working

(inline if) in java won't work if you are using 'if' statement .. the right syntax is in the following example:

int y = (c == 19) ? 7 : 11 ; 

or

String y = (s > 120) ? "Slow Down" : "Safe";
System.out.println(y);

as You can see the type of the variable Y is the same as the return value ...

in your case it is better to use the normal if statement not inline if as it is in the pervious answer without "?"

if (compareChar(curChar, toChar("0"))) getButtons().get(i).setText("§");

Any way to limit border length?

Borders are defined per side only, not in fractions of a side. So, no, you can't do that.

Also, a new element wouldn't be a border either, it would only mimic the behaviour you want - but it would still be an element.

What are "res" and "req" parameters in Express functions?

req is an object containing information about the HTTP request that raised the event. In response to req, you use res to send back the desired HTTP response.

Those parameters can be named anything. You could change that code to this if it's more clear:

app.get('/user/:id', function(request, response){
  response.send('user ' + request.params.id);
});

Edit:

Say you have this method:

app.get('/people.json', function(request, response) { });

The request will be an object with properties like these (just to name a few):

  • request.url, which will be "/people.json" when this particular action is triggered
  • request.method, which will be "GET" in this case, hence the app.get() call.
  • An array of HTTP headers in request.headers, containing items like request.headers.accept, which you can use to determine what kind of browser made the request, what sort of responses it can handle, whether or not it's able to understand HTTP compression, etc.
  • An array of query string parameters if there were any, in request.query (e.g. /people.json?foo=bar would result in request.query.foo containing the string "bar").

To respond to that request, you use the response object to build your response. To expand on the people.json example:

app.get('/people.json', function(request, response) {
  // We want to set the content-type header so that the browser understands
  //  the content of the response.
  response.contentType('application/json');

  // Normally, the data is fetched from a database, but we can cheat:
  var people = [
    { name: 'Dave', location: 'Atlanta' },
    { name: 'Santa Claus', location: 'North Pole' },
    { name: 'Man in the Moon', location: 'The Moon' }
  ];

  // Since the request is for a JSON representation of the people, we
  //  should JSON serialize them. The built-in JSON.stringify() function
  //  does that.
  var peopleJSON = JSON.stringify(people);

  // Now, we can use the response object's send method to push that string
  //  of people JSON back to the browser in response to this request:
  response.send(peopleJSON);
});

How do I view the SQLite database on an Android device?

Using file explorer, you can locate your database file like this:

data-->data-->your.package.name-->databases--->yourdbfile.db

Then you can use any SQLite fronted to explore your database. I use the SQLite Manager Firefox addon. It's nice, small, and fast.

SQL query for extracting year from a date

How about this one?

SELECT TO_CHAR(ASOFDATE, 'YYYY') FROM PSASOFDATE

Failed to load AppCompat ActionBar with unknown error in android studio

Method 1:

Locate /res/values/styles.xml

Change

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">

To

<style name="AppTheme" parent="Base.Theme.AppCompat.Light.DarkActionBar">

Method 2:

Modify template file(locate: android-studio/plugins/android/lib/templates/gradle-projects/NewAndroidModule/root/res/values/styles.xml.ftl)

Change

backwardsCompatibility!true>Theme.AppCompat<#else><#if

To

backwardsCompatibility!true>Base.Theme.AppCompat<#else><#if

Watch Solution On YouTube

Solution

Multiple controllers with AngularJS in single page app

I just put one simple declaration of the app

var app = angular.module("app", ["xeditable"]);

Then I built one service and two controllers

For each controller I had a line in the JS

app.controller('EditableRowCtrl', function ($scope, CRUD_OperService) {

And in the HTML I declared the app scope in a surrounding div

<div ng-app="app">

and each controller scope separately in their own surrounding div (within the app div)

<div ng-controller="EditableRowCtrl">

This worked fine

Makefile ifeq logical or

As found on the mailing list archive,

one can use the filter function.

For example

ifeq ($(GCC_MINOR),$(filter $(GCC_MINOR),4 5))

filter X, A B will return those of A,B that are equal to X. Note, while this is not relevant in the above example, this is a XOR operation. I.e. if you instead have something like:

ifeq (4, $(filter 4, $(VAR1) $(VAR2)))

And then do e.g. make VAR1=4 VAR2=4, the filter will return 4 4, which is not equal to 4.

A variation that performs an OR operation instead is:

ifneq (,$(filter $(GCC_MINOR),4 5))

where a negative comparison against an empty string is used instead (filter will return en empty string if GCC_MINOR doesn't match the arguments). Using the VAR1/VAR2 example it would look like this:

ifneq (, $(filter 4, $(VAR1) $(VAR2)))

The downside to those methods is that you have to be sure that these arguments will always be single words. For example, if VAR1 is 4 foo, the filter result is still 4, and the ifneq expression is still true. If VAR1 is 4 5, the filter result is 4 5 and the ifneq expression is true.

One easy alternative is to just put the same operation in both the ifeq and else ifeq branch, e.g. like this:

ifeq ($(GCC_MINOR),4)
    @echo Supported version
else ifeq ($(GCC_MINOR),5)
    @echo Supported version
else
    @echo Unsupported version
endif

HTML Button Close Window

Closing a window that was opened by the user through JavaScript is considered to be a security risk, thus not all browsers will allow this (which is why all solutions are hacks/workarounds). Browsers that are steadily maintained remove these types of hacks, and solutions that work one day may be broken the next.

This was addressed here by rvighne in a similar question on the subject.

set option "selected" attribute from dynamic created option

Good question. You will need to modify the HTML itself rather than rely on DOM properties.

var opt = $("option[val=ID]"),
    html = $("<div>").append(opt.clone()).html();
html = html.replace(/\>/, ' selected="selected">');
opt.replaceWith(html);

The code grabs the option element for Indonesia, clones it and puts it into a new div (not in the document) to retrieve the full HTML string: <option value="ID">Indonesia</option>.

It then does a string replace to add the attribute selected="selected" as a string, before replacing the original option with this new one.

I tested it on IE7. See it with the reset button working properly here: http://jsfiddle.net/XmW49/

SSRS Query execution failed for dataset

In addition to the above answers, it could be due to a missing SQL stored-procedure or SQL function. For example, this could be due to the function not migrating from a non-prod region to the production (prod) region.

Use a LIKE statement on SQL Server XML Datatype

Yet another option is to cast the XML as nvarchar, and then search for the given string as if the XML vas a nvarchar field.

SELECT * 
FROM Table
WHERE CAST(Column as nvarchar(max)) LIKE '%TEST%'

I love this solution as it is clean, easy to remember, hard to mess up, and can be used as a part of a where clause.

EDIT: As Cliff mentions it, you could use:

...nvarchar if there's characters that don't convert to varchar

Unable to install packages in latest version of RStudio and R Version.3.1.1

Please check the following to be able to install new packages:

1- In Tools -> Global Options -> Packages, uncheck the "Use Internet Explorer library/proxy for HTTP" option,

2- In Tools -> Global Options -> Packages, change the CRAN mirror to "0- Cloud - Rstudio, automatic redirection to servers worldwide"

3- Restart Rstudio.

4- Have fun!

Spring-boot default profile for integration tests

To activate "test" profile write in your build.gradle:

    test.doFirst {
        systemProperty 'spring.profiles.active', 'test'
        activeProfiles = 'test'
    }

jquery stop child triggering parent event

Or, rather than having an extra event handler to prevent another handler, you can use the Event Object argument passed to your click event handler to determine whether a child was clicked. target will be the clicked element and currentTarget will be the .header div:

$(".header").click(function(e){
     //Do nothing if .header was not directly clicked
     if(e.target !== e.currentTarget) return;

     $(this).children(".children").toggle();
});

How to check whether a string is a valid HTTP URL?

This method works fine both in http and https. Just one line :)

if (Uri.IsWellFormedUriString("https://www.google.com", UriKind.Absolute))

MSDN: IsWellFormedUriString

How to reverse an std::string?

I'm not sure what you mean by a string that contains binary numbers. But for reversing a string (or any STL-compatible container), you can use std::reverse(). std::reverse() operates in place, so you may want to make a copy of the string first:

#include <algorithm>
#include <iostream>
#include <string>

int main()
{
    std::string foo("foo");
    std::string copy(foo);
    std::cout << foo << '\n' << copy << '\n';

    std::reverse(copy.begin(), copy.end());
    std::cout << foo << '\n' << copy << '\n';
}

Python: URLError: <urlopen error [Errno 10060]

This is because of the proxy settings. I also had the same problem, under which I could not use any of the modules which were fetching data from the internet. There are simple steps to follow:
1. open the control panel
2. open internet options
3. under connection tab open LAN settings
4. go to advance settings and unmark everything, delete every proxy in there. Or u can just unmark the checkbox in proxy server this will also do the same
5. save all the settings by clicking ok.
you are done. try to run the programme again, it must work it worked for me at least

Absolute vs relative URLs

Let's say you have a site www.yourserver.com. In the root directory for web documents you have an images sub-directoy and in that you have myimage.jpg.

An absolute URL defines the exact location of the document, for example:

http://www.yourserver.com/images/myimage.jpg

A relative URL defines the location relative to the current directory, for example, given you are in the root web directory your image is in:

images/myimage.jpg

(relative to that root directory)

You should always use relative URLS where possible. If you move the site to www.anotherserver.com you would have to update all the absolute URLs that were pointing at www.yourserver.com, relative ones will just keep working as is.

What does enumerate() mean?

I am assuming that you know how to iterate over elements in some list:

for el in my_list:
    # do something

Now sometimes not only you need to iterate over the elements, but also you need the index for each iteration. One way to do it is:

i = 0
for el in my_list:
    # do somethings, and use value of "i" somehow
    i += 1

However, a nicer way is to user the function "enumerate". What enumerate does is that it receives a list, and it returns a list-like object (an iterable that you can iterate over) but each element of this new list itself contains 2 elements: the index and the value from that original input list: So if you have

arr = ['a', 'b', 'c']

Then the command enumerate(arr) returns something like:

[(0,'a'), (1,'b'), (2,'c')]

Now If you iterate over a list (or an iterable) where each element itself has 2 sub-elements, you can capture both of those sub-elements in the for loop like below:

for index, value in enumerate(arr):
    print(index,value)

which would print out the sub-elements of the output of enumerate.

And in general you can basically "unpack" multiple items from list into multiple variables like below:

idx,value = (2,'c')
print(idx)
print(value)

which would print

2
c

This is the kind of assignment happening in each iteration of that loop with enumerate(arr) as iterable.

Detect if string contains any spaces

var inValid = new RegExp('^[_A-z0-9]{1,}$');
var value = "test string";
var k = inValid.test(value);
alert(k);

What is the most effective way for float and double comparison?

As others have pointed out, using a fixed-exponent epsilon (such as 0.0000001) will be useless for values away from the epsilon value. For example, if your two values are 10000.000977 and 10000, then there are NO 32-bit floating-point values between these two numbers -- 10000 and 10000.000977 are as close as you can possibly get without being bit-for-bit identical. Here, an epsilon of less than 0.0009 is meaningless; you might as well use the straight equality operator.

Likewise, as the two values approach epsilon in size, the relative error grows to 100%.

Thus, trying to mix a fixed point number such as 0.00001 with floating-point values (where the exponent is arbitrary) is a pointless exercise. This will only ever work if you can be assured that the operand values lie within a narrow domain (that is, close to some specific exponent), and if you properly select an epsilon value for that specific test. If you pull a number out of the air ("Hey! 0.00001 is small, so that must be good!"), you're doomed to numerical errors. I've spent plenty of time debugging bad numerical code where some poor schmuck tosses in random epsilon values to make yet another test case work.

If you do numerical programming of any kind and believe you need to reach for fixed-point epsilons, READ BRUCE'S ARTICLE ON COMPARING FLOATING-POINT NUMBERS.

Comparing Floating Point Numbers

MySQL Select all columns from one table and some from another table

Using alias for referencing the tables to get the columns from different tables after joining them.

Select tb1.*, tb2.col1, tb2.col2 from table1 tb1 JOIN table2 tb2 on tb1.Id = tb2.Id

Get nth character of a string in Swift programming language

I wanted to point out that if you have a large string and need to randomly access many characters from it, you may want to pay the extra memory cost and convert the string to an array for better performance:

// Pay up front for O(N) memory
let chars = Array(veryLargeString.characters)

for i in 0...veryLargeNumber {
    // Benefit from O(1) access
    print(chars[i])
}

increase font size of hyperlink text html

increase the padding size of font and then try to increase font size:-

style="padding-bottom:40px; font-size: 50px;"

how to auto select an input field and the text in it on page load

To do it on page load:

_x000D_
_x000D_
window.onload = function () {_x000D_
  var input = document.getElementById('myTextInput');_x000D_
  input.focus();_x000D_
  input.select();_x000D_
}
_x000D_
<input id="myTextInput" value="Hello world!" />
_x000D_
_x000D_
_x000D_

Angularjs dynamic ng-pattern validation

I just ran into this the other day.

What I did, which seems easier than the above, is to set the pattern on a variable on the scope and refer to it in ng-pattern in the view.

When "the checkbox is unchecked" I simply set the regex value to /.*/ on the onChanged callback (if going to unchecked). ng-pattern picks that change up and says "OK, your value is fine". Form is now valid. I would also remove the bad data from the field so you don't have an apparent bad phone # sitting there.

I had additional issues around ng-required, and did the same thing. Worked like a charm.

Force decimal point instead of comma in HTML5 number input (client-side)

I have written a custom piece of code to do this

If you want to replace , with ., remove translate_decimals functions completely.

_x000D_
_x000D_
var input = document.querySelector('input[role="custom-number"]');_x000D_
var bincr = document.querySelector('button[role="increment"]');_x000D_
var bdecr = document.querySelector('button[role="decrement"]');_x000D_
_x000D_
function translate_decimals(side = 0)_x000D_
{_x000D_
 input.value = (side == ',' ? input.value.replace('.',',') : input.value.replace(',','.'));_x000D_
}_x000D_
translate_decimals(',');_x000D_
_x000D_
bincr.addEventListener('click', ()=>{_x000D_
 if (input.hasAttribute('max'))_x000D_
 {_x000D_
  if (input.value.substr(0,input.getAttribute('max').length) == input.getAttribute('max').substr(0,input.getAttribute('max').length))_x000D_
  {_x000D_
   return;_x000D_
  }_x000D_
  else_x000D_
  {_x000D_
   translate_decimals('.');_x000D_
   let temp = input.value;_x000D_
   input.value = "";_x000D_
   input.value = (input.hasAttribute('step') ? (parseFloat(temp) + parseFloat(input.getAttribute('step'))) : temp++);_x000D_
   translate_decimals(',');_x000D_
  }_x000D_
 }_x000D_
});_x000D_
_x000D_
bdecr.addEventListener('click', ()=>{_x000D_
 if (input.hasAttribute('min'))_x000D_
 {_x000D_
  if (input.value.substr(0,input.getAttribute('min').length) == input.getAttribute('min').substr(0,input.getAttribute('min').length))_x000D_
  {_x000D_
   return;_x000D_
  }_x000D_
  else_x000D_
  {_x000D_
   translate_decimals('.');_x000D_
   input.value = (input.hasAttribute('step') ? (input.value - input.getAttribute('step')) : input.value--);_x000D_
   translate_decimals(',');_x000D_
  }_x000D_
 }_x000D_
});
_x000D_
/* styling increment & decrement buttons */_x000D_
button[role="increment"],_x000D_
button[role="decrement"] {_x000D_
 width:32px;_x000D_
}
_x000D_
<input type="text" role="custom-number" step="0.01" min="0" max="0" lang="en" value="1.99">_x000D_
<button role="increment">+</button>_x000D_
<button role="decrement">-</button>
_x000D_
_x000D_
_x000D_

Storing files in SQL Server

You might read up on FILESTREAM. Here is some info from the docs that should help you decide:

If the following conditions are true, you should consider using FILESTREAM:

  • Objects that are being stored are, on average, larger than 1 MB.
  • Fast read access is important.
  • You are developing applications that use a middle tier for application logic.

For smaller objects, storing varbinary(max) BLOBs in the database often provides better streaming performance.

How can you customize the numbers in an ordered list?

HTML5: Use the value attribute (no CSS needed)

Modern browsers will interpret the value attribute and will display it as you expect. See MDN documentation.

_x000D_
_x000D_
<ol>_x000D_
  <li value="3">This is item three.</li>_x000D_
  <li value="50">This is item fifty.</li>_x000D_
  <li value="100">This is item one hundred.</li>_x000D_
</ol>
_x000D_
_x000D_
_x000D_

Also have a look at the <ol> article on MDN, especially the documentation for the start and attribute.

clear javascript console in Google Chrome

On the Mac you can also use ?+K just like in Terminal.

Running Facebook application on localhost

2013 August. Facebook doesn't allow to set domain with port for an App, as example "localhost:3000".

So you can use https://pagekite.net to tunnel your localhost:port to proper domain.

Rails developers can use http://progrium.com/localtunnel/ for free.

  • Facebook allows only one domain for App at the time. If you are trying to add another one, as localhost, it will show some kind of different error about domain. Be sure to use only one domain for callback and for app domain setting at the time.

Which Architecture patterns are used on Android?

I tried using both the model–view–controller (MVC) and model–view–presenter architectural patterns for doing android development. My findings are model–view–controller works fine, but there are a couple of "issues". It all comes down to how you perceive the Android Activity class. Is it a controller, or is it a view?

The actual Activity class doesn't extend Android's View class, but it does, however, handle displaying a window to the user and also handle the events of that window (onCreate, onPause, etc.).

This means, that when you are using an MVC pattern, your controller will actually be a pseudo view–controller. Since it is handling displaying a window to the user, with the additional view components you have added to it with setContentView, and also handling events for at least the various activity life cycle events.

In MVC, the controller is supposed to be the main entry point. Which is a bit debatable if this is the case when applying it to Android development, since the activity is the natural entry point of most applications.

Because of this, I personally find that the model–view–presenter pattern is a perfect fit for Android development. Since the view's role in this pattern is:

  • Serving as a entry point
  • Rendering components
  • Routing user events to the presenter

This allows you to implement your model like so:

View - this contains your UI components, and handles events for them.

Presenter - this will handle communication between your model and your view, look at it as a gateway to your model. Meaning, if you have a complex domain model representing, God knows what, and your view only needs a very small subset of this model, the presenters job is to query the model and then update the view. For example, if you have a model containing a paragraph of text, a headline and a word-count. But in a given view, you only need to display the headline in the view. Then the presenter will read the data needed from the model, and update the view accordingly.

Model - this should basically be your full domain model. Hopefully it will help making your domain model more "tight" as well, since you won't need special methods to deal with cases as mentioned above.

By decoupling the model from the view all together (through use of the presenter), it also becomes much more intuitive to test your model. You can have unit tests for your domain model, and unit tests for your presenters.

Try it out. I personally find it a great fit for Android development.

Object cannot be cast from DBNull to other types

TryParse is usually the most elegant way to handle this type of thing:

long temp = 0;
if (Int64.TryParse(dataAccCom.GetParameterValue(IDbCmd, "op_Id").ToString(), out temp))
{
   DataTO.Id = temp;
}     

React passing parameter via onclick event using ES6 syntax

Remember that in onClick={ ... }, the ... is a JavaScript expression. So

... onClick={this.handleRemove(id)}

is the same as

var val = this.handleRemove(id);
... onClick={val}

In other words, you call this.handleRemove(id) immediately, and pass that value to onClick, which isn't what you want.

Instead, you want to create a new function with one of the arguments already prefilled; essentially, you want the following:

var newFn = function() {
  var args = Array.prototype.slice.call(arguments);

  // args[0] contains the event object
  this.handleRemove.apply(this, [id].concat(args));
}
... onClick={newFn}

There is a way to express this in ES5 JavaScript: Function.prototype.bind.

... onClick={this.handleRemove.bind(this, id)}

If you use React.createClass, React automatically binds this for you on instance methods, and it may complain unless you change it to this.handleRemove.bind(null, id).

You can also simply define the function inline; this is made shorter with arrow functions if your environment or transpiler supports them:

... onClick={() => this.handleRemove(id)}

If you need access to the event, you can just pass it along:

... onClick={(evt) => this.handleRemove(id, evt)}

How can I convert an HTML element to a canvas element?

Sorry, the browser won't render HTML into a canvas.

It would be a potential security risk if you could, as HTML can include content (in particular images and iframes) from third-party sites. If canvas could turn HTML content into an image and then you read the image data, you could potentially extract privileged content from other sites.

To get a canvas from HTML, you'd have to basically write your own HTML renderer from scratch using drawImage and fillText, which is a potentially huge task. There's one such attempt here but it's a bit dodgy and a long way from complete. (It even attempts to parse the HTML/CSS from scratch, which I think is crazy! It'd be easier to start from a real DOM node with styles applied, and read the styling using getComputedStyle and relative positions of parts of it using offsetTop et al.)

How to make a submit out of a <a href...>...</a> link?

Dont forget the "BUTTON" element wich can handle some more HTML inside...

How to export and import a .sql file from command line with options?

Well you can use below command to export,

mysqldump --databases --user=root --password your_db_name > export_into_db.sql

and the generated file will be available in the same directory where you had ran this command.

Now login to mysql using command,

mysql -u[username] -p

then use "source" command with the file path.

How to make a JTable non-editable

create new DefaultCellEditor class :

public static class Editor_name extends DefaultCellEditor {
  public Editor_name(JCheckBox checkBox) {
   super(checkBox);
  }
  @Override
  public boolean isCellEditable(EventObject anEvent) {
    return false;
  }
}

and use setCellEditor :

JTable table = new JTable();
table.getColumn("columnName").setCellEditor(new Editor_name(new JCheckBox()));

How to Apply Corner Radius to LinearLayout

You can create an XML file in the drawable folder. Call it, for example, shape.xml

In shape.xml:

<shape
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle"   >

    <solid
        android:color="#888888" >
    </solid>

    <stroke
        android:width="2dp"
        android:color="#C4CDE0" >
    </stroke>

    <padding
        android:left="5dp"
        android:top="5dp"
        android:right="5dp"
        android:bottom="5dp"    >
    </padding>

    <corners
        android:radius="11dp"   >
    </corners>

</shape>

The <corner> tag is for your specific question.

Make changes as required.

And in your whatever_layout_name.xml:

<LinearLayout
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:layout_margin="5dp"
    android:background="@drawable/shape"    >
</LinearLayout>

This is what I usually do in my apps. Hope this helps....

Best way to alphanumeric check in JavaScript

The asker's original inclination to use str.charCodeAt(i) appears to be faster than the regular expression alternative. In my test on jsPerf the RegExp option performs 66% slower in Chrome 36 (and slightly slower in Firefox 31).

Here's a cleaned-up version of the original validation code that receives a string and returns true or false:

function isAlphaNumeric(str) {
  var code, i, len;

  for (i = 0, len = str.length; i < len; i++) {
    code = str.charCodeAt(i);
    if (!(code > 47 && code < 58) && // numeric (0-9)
        !(code > 64 && code < 91) && // upper alpha (A-Z)
        !(code > 96 && code < 123)) { // lower alpha (a-z)
      return false;
    }
  }
  return true;
};

Of course, there may be other considerations, such as readability. A one-line regular expression is definitely prettier to look at. But if you're strictly concerned with speed, you may want to consider this alternative.

Render Content Dynamically from an array map function in React Native

Try moving the lapsList function out of your class and into your render function:

render() {
  const lapsList = this.state.laps.map((data) => {
    return (
      <View><Text>{data.time}</Text></View>
    )
  })

  return (
    <View style={styles.container}>
      <View style={styles.footer}>
        <View><Text>coucou test</Text></View>
        {lapsList}
      </View>
    </View>
  )
}

Why do we not have a virtual constructor in C++?

Cant we simply say it like.. We cannot inherit constructors. So there is no point declaring them virtual because the virtual provides polymorphism .

SVG fill color transparency / alpha?

As a not yet fully standardized solution (though in alignment with the color syntax in CSS3) you can use e.g fill="rgba(124,240,10,0.5)". Works fine in Firefox, Opera, Chrome.

Here's an example.

How to read a string one letter at a time in python

# Retain a map of the Morse code
conversion = {}

# Read map from file, add it to the datastructure
morseCodeFile = file('morseCode.txt')
for line in moreCodeFile:
    conversion[line[0]] = line[2:]
morseCodeFile.close()

# Ask for input from the user
s = raw_input("Please enter string to translate")
# Go over each character, and print it the translation.
# Defensive programming: do something sane if the user 
# inputs non-Morse compatible strings.    
for c in s:
    print conversion.get(c, "No translation for "+c)

How do I get cURL to not show the progress bar?

curl -s http://google.com > temp.html

works for curl version 7.19.5 on Ubuntu 9.10 (no progress bar). But if for some reason that does not work on your platform, you could always redirect stderr to /dev/null:

curl  http://google.com 2>/dev/null > temp.html

Simple way to understand Encapsulation and Abstraction

Encapsulation can be thought of as wrapping paper used to bind data and function together as a single unit which protects it from all kinds of external dirt (I mean external functions).

Abstraction involves absence of details and the use of a simple interface to control a complex system.

For example we can light a bulb by the pressing of a button without worrying about the underlying electrical engineering (Abstraction) .

However u cannot light the bulb in any other way. (Encapsulation)

At least one JAR was scanned for TLDs yet contained no TLDs

(tomcat 8.0.28) Above method did not work for me. This is what worked:

  1. Add this line to the end of your {CATALINA-HOME}/conf/logging.properties:

    org.apache.jasper.level = FINEST
    
  2. Shut down the server (if started).

  3. Open console and run (in case of Windows):

    %CATALINA_HOME%\bin\catalina.bat run
    
  4. Enjoy logs, e.g. (again, for Windows):

    {CATALINA-HOME}/logs/catalina.2015-12-28.log
    

I gave up on integrating this with Eclipse launch configuration so be aware that this works only from console, launching the server from Eclipse won't produce additional log messages.

Can a constructor in Java be private?

yes a constructor can be private. A private Constructor prevents any other class from instantiating example of private constructor

public class CustomHttpClient {
private static HttpClient customHttpClient;

/** A private Constructor prevents any other class from instantiating. */
private CustomHttpClient() {
}}

SQLSTATE[HY000] [1045] Access denied for user 'username'@'localhost' using CakePHP

I want to add to the answers posted on above that none of the solutions proposed here worked for me. My WAMP, is working on port 3308 instead of 3306 which is what it is installed by default. I found out that when working in a local environment, if you are using mysqladmin in your computer (for testing environment), and if you are working with port other than 3306, you must define your variable DB_SERVER with the value localhost:NumberOfThePort, so it will look like the following: define("DB_SERVER", "localhost:3308"). You can obtain this value by right-clicking on the WAMP icon in your taskbar (on the hidden icons section) and select Tools. You will see the section: "Port used by MySQL: NumberOfThePort"

This will fix your connection to your database.

This was the error I got: Error: SQLSTATE[HY1045] Access denied for user 'username'@'localhost' on line X.

I hope this helps you out.

:)

get the latest fragment in backstack

Keep your own back stack: myBackStack. As you Add a fragment to the FragmentManager, also add it to myBackStack. In onBackStackChanged() pop from myBackStack when its length is greater than getBackStackEntryCount.

Char to int conversion in C

Since the ASCII codes for '0','1','2'.... are placed from 48 to 57 they are essentially continuous. Now the arithmetic operations require conversion of char datatype to int datatype.Hence what you are basically doing is: 53-48 and hence it stores the value 5 with which you can do any integer operations.Note that while converting back from int to char the compiler gives no error but just performs a modulo 256 operation to put the value in its acceptable range

How to enable bulk permission in SQL Server

SQL Server may also return this error if the service account does not have permission to read the file being imported. Ensure that the service account has read access to the file location. For example:

icacls D:\ImportFiles /Grant "NT Service\MSSQLServer":(OI)(CI)R

How to find out which processes are using swap space in Linux?

Yet two more variants:

Because top or htop could be not installed on small systems, browsing /proc stay always possible.

Even on small systems, you will found a shell...

A variant! (Not bash only)

This is exactly same than lolotux script, but without any fork to grep, awk or ps. This is a lot quicker!

And as is one of the poorest regarding performance, a little work was done to ensure this script will run well under , and some other. Then, (thanks to Stéphane Chazelas,) become a lot quicker again!

#!/bin/sh 
# Get current swap usage for all running processes
# Felix Hauri 2016-08-05
# Rewritted without fork. Inspired by first stuff from
# Erik Ljungstrom 27/05/2011
# Modified by Mikko Rantalainen 2012-08-09
# Pipe the output to "sort -nk3" to get sorted output
# Modified by Marc Methot 2014-09-18
# removed the need for sudo

OVERALL=0
rifs=`printf ': \t'`
for FILE in /proc/[0-9]*/status ;do
    SUM=0
    while IFS="$rifs" read FIELD VALUE ;do
        case $FIELD in
            Pid )    PID=$VALUE      ;;
            Name )   PROGNAME="$VALUE" ;;
            VmSwap ) SUM=$((SUM=${VALUE% *}))  ;;
        esac
    done <$FILE
    [ $SUM -gt 0 ] &&
        printf "PID: %9d  swapped: %11d KB (%s)\n" $PID $SUM "$PROGNAME"
    OVERALL=$((OVERALL+SUM))
done
printf "Total swapped memory: %14u KB\n" $OVERALL

Don't forgot to double quote "$PROGNAME" ! See Stéphane Chazelas's comment:

read FIELD PROGNAME < <(
    perl -ne 'BEGIN{$0="/*/*/../../*/*"} print if /^Name/' /proc/self/status
)
echo $FIELD "$PROGNAME"

Don't try echo $PROGNAME without double quote on sensible system, and be ready to kill current shell before!

And a version

As this become a not so simple script, time is comming to write a dedicated tool by using more efficient language.

#!/usr/bin/perl -w

use strict;
use Getopt::Std;
my ($tot,$mtot)=(0,0);
my %procs;

my %opts;
getopt('', \%opts);

sub sortres {
    return $a <=> $b                                          if $opts{'p'};
    return $procs{$a}->{'cmd'} cmp $procs{$b}->{'cmd'}        if $opts{'c'};
    return $procs{$a}->{'mswap'} <=> $procs{$b}->{'mswap'}    if $opts{'m'};
    return $procs{$a}->{'swap'} <=> $procs{$b}->{'swap'};
};

opendir my $dh,"/proc";

for my $pid (grep {/^\d+$/} readdir $dh) {
    if (open my $fh,"</proc/$pid/status") {
        my ($sum,$nam)=(0,"");
        while (<$fh>) {
            $sum+=$1 if /^VmSwap:\s+(\d+)\s/;
            $nam=$1 if /^Name:\s+(\S+)/;
        }
        if ($sum) {
            $tot+=$sum;
            $procs{$pid}->{'swap'}=$sum;
            $procs{$pid}->{'cmd'}=$nam;
            close $fh;
            if (open my $fh,"</proc/$pid/smaps") {
                $sum=0;
                while (<$fh>) {
                    $sum+=$1 if /^Swap:\s+(\d+)\s/;
                };
            };
            $mtot+=$sum;
            $procs{$pid}->{'mswap'}=$sum;
        } else { close $fh; };
    };
};
map {
    printf "PID: %9d  swapped: %11d (%11d) KB (%s)\n",
        $_, $procs{$_}->{'swap'}, $procs{$_}->{'mswap'}, $procs{$_}->{'cmd'};
} sort sortres keys %procs;
printf "Total swapped memory: %14u (%11u) KB\n", $tot,$mtot;

could by run with one of

-c  sort by command name
-p  sort by pid
-m  sort by swap values
by default, output is sorted by status's vmsize

Get first key in a (possibly) associative array?

use :

$array = ['po','co','so'];

echo reset($array); 

Result : po

How to use terminal commands with Github?

To add all file at a time, use git add -A

To check git whole status, use git log

C++ unordered_map using a custom class type as the key

For enum type, I think this is a suitable way, and the difference between class is how to calculate hash value.

template <typename T>
struct EnumTypeHash {
  std::size_t operator()(const T& type) const {
    return static_cast<std::size_t>(type);
  }
};

enum MyEnum {};
class MyValue {};

std::unordered_map<MyEnum, MyValue, EnumTypeHash<MyEnum>> map_;

<ng-container> vs <template>

Imo use cases for ng-container are simple replacements for which a custom template/component would be overkill. In the API doc they mention the following

use a ng-container to group multiple root nodes

and I guess that's what it is all about: grouping stuff.

Be aware that the ng-container directive falls away instead of a template where its directive wraps the actual content.

Android Canvas.drawText

Worked this out, turns out that android.R.color.black is not the same as Color.BLACK. Changed the code to:

Paint paint = new Paint(); 
paint.setColor(Color.WHITE); 
paint.setStyle(Style.FILL); 
canvas.drawPaint(paint); 

paint.setColor(Color.BLACK); 
paint.setTextSize(20); 
canvas.drawText("Some Text", 10, 25, paint); 

and it all works fine now!!

/usr/lib/libstdc++.so.6: version `GLIBCXX_3.4.15' not found

I got same error. This is how it worked for me:

  • cleaned the project under currently installed gcc
  • recompiled it

Worked perfectly!

How can I create objects while adding them into a vector?

To answer the first part of your question, you must create an object of type Player before you can use it. When you say push_back(Player), it means "add the Player class to the vector", not "add an object of type Player to the vector" (which is what you meant).

You can create the object on the stack like this:

Player player;
vectorOfGamers.push_back(player);    // <-- name of variable, not type

Or you can even create a temporary object inline and push that (it gets copied when it's put in the vector):

vectorOfGamers.push_back(Player());    // <-- parentheses create a "temporary"

To answer the second part, you can create a vector of the base type, which will allow you to push back objects of any subtype; however, this won't work as expected:

vector<Gamer> gamers;
gamers.push_back(Dealer());    // Doesn't work properly!

since when the dealer object is put into the vector, it gets copied as a Gamer object -- this means only the Gamer part is copied effectively "slicing" the object. You can use pointers, however, since then only the pointer would get copied, and the object is never sliced:

vector<Gamer*> gamers;
gamers.push_back(new Dealer());    // <-- Allocate on heap with `new`, since we
                                   // want the object to persist while it's
                                   // pointed to

AngularJS HTTP post to PHP and undefined

In the API I am developing I have a base controller and inside its __construct() method I have the following:

if(isset($_SERVER["CONTENT_TYPE"]) && strpos($_SERVER["CONTENT_TYPE"], "application/json") !== false) {
    $_POST = array_merge($_POST, (array) json_decode(trim(file_get_contents('php://input')), true));
}

This allows me to simply reference the json data as $_POST["var"] when needed. Works great.

That way if an authenticated user connects with a library such a jQuery that sends post data with a default of Content-Type: application/x-www-form-urlencoded or Content-Type: application/json the API will respond without error and will make the API a little more developer friendly.

Hope this helps.

SELECT INTO Variable in MySQL DECLARE causes syntax error?

Per the MySQL docs DECLARE works only at the start of a BEGIN...END block as in a stored program.

Why should you use strncpy instead of strcpy?

While I know the intent behind strncpy, it is not really a good function. Avoid both. Raymond Chen explains.

Personally, my conclusion is simply to avoid strncpy and all its friends if you are dealing with null-terminated strings. Despite the "str" in the name, these functions do not produce null-terminated strings. They convert a null-terminated string into a raw character buffer. Using them where a null-terminated string is expected as the second buffer is plain wrong. Not only do you fail to get proper null termination if the source is too long, but if the source is short you get unnecessary null padding.

See also Why is strncpy insecure?

how to get program files x86 env variable?

IMHO, one point that is missing in this discussion is that whatever variable you use, it is guaranteed to always point at the appropriate folder. This becomes critical in the rare cases where Windows is installed on a drive other than C:\

Where is jarsigner?

For posterity's sake, if you are trying to actually use jarsigner to sign a jar file (such as that of an applet) with a keystore, you'll need to reference jarsigner while running the command from the folder that your keystore is in:

cd "C:\Program Files\Java\jre(version#)\bin"

then

"C:\Program Files\Java\jdk(version#)\bin\jarsigner.exe" -keystore mykeystore (PATH TO YOUR .JAR)\MyJarFile.jar alias

The above might be obvious, but it took me a few tries because I was trying to call jarsigner while inside the JDK folder, which had no knowledge of where my keystore was (in the jre directory!), so I hope this will help those who would like to see a usable syntax for that situation.

Hadoop "Unable to load native-hadoop library for your platform" warning

I had the same problem with JDK6,I changed the JDK to JDK8,the problem solved. Try to use JDK8!!!

Django 1.7 - makemigrations not detecting changes

You may need to fake the initial migrations using the command below

python manage.py migrate --fake-initial

Android basics: running code in the UI thread

If you need to use in Fragment you should use

private Context context;

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        this.context = context;
    }


    ((MainActivity)context).runOnUiThread(new Runnable() {
        public void run() {
            Log.d("UI thread", "I am the UI thread");
        }
    });

instead of

getActivity().runOnUiThread(new Runnable() {
    public void run() {
        Log.d("UI thread", "I am the UI thread");
    }
});

Because There will be null pointer exception in some situation like pager fragment

Which characters make a URL invalid?

To add some clarification and directly address the question above, there are several classes of characters that cause problems for URLs and URIs.

There are some characters that are disallowed and should never appear in a URL/URI, reserved characters (described below), and other characters that may cause problems in some cases, but are marked as "unwise" or "unsafe". Explanations for why the characters are restricted are clearly spelled out in RFC-1738 (URLs) and RFC-2396 (URIs). Note the newer RFC-3986 (update to RFC-1738) defines the construction of what characters are allowed in a given context but the older spec offers a simpler and more general description of which characters are not allowed with the following rules.

Excluded US-ASCII Characters disallowed within the URI syntax:

   control     = <US-ASCII coded characters 00-1F and 7F hexadecimal>
   space       = <US-ASCII coded character 20 hexadecimal>
   delims      = "<" | ">" | "#" | "%" | <">

The character "#" is excluded because it is used to delimit a URI from a fragment identifier. The percent character "%" is excluded because it is used for the encoding of escaped characters. In other words, the "#" and "%" are reserved characters that must be used in a specific context.

List of unwise characters are allowed but may cause problems:

   unwise      = "{" | "}" | "|" | "\" | "^" | "[" | "]" | "`"

Characters that are reserved within a query component and/or have special meaning within a URI/URL:

  reserved    = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" | "$" | ","

The "reserved" syntax class above refers to those characters that are allowed within a URI, but which may not be allowed within a particular component of the generic URI syntax. Characters in the "reserved" set are not reserved in all contexts. The hostname, for example, can contain an optional username so it could be something like ftp://user@hostname/ where the '@' character has special meaning.

Here is an example of a URL that has invalid and unwise characters (e.g. '$', '[', ']') and should be properly encoded:

http://mw1.google.com/mw-earth-vectordb/kml-samples/gp/seattle/gigapxl/$[level]/r$[y]_c$[x].jpg

Some of the character restrictions for URIs and URLs are programming language-dependent. For example, the '|' (0x7C) character although only marked as "unwise" in the URI spec will throw a URISyntaxException in the Java java.net.URI constructor so a URL like http://api.google.com/q?exp=a|b is not allowed and must be encoded instead as http://api.google.com/q?exp=a%7Cb if using Java with a URI object instance.

Moving from one activity to another Activity in Android

First you have to declare the activity in Manifest. It is important. You can add this inside application like this.

Catching "Maximum request length exceeded"

How about catch it at EndRequest event?

protected void Application_EndRequest(object sender, EventArgs e)
    {
        HttpRequest request = HttpContext.Current.Request;
        HttpResponse response = HttpContext.Current.Response;
        if ((request.HttpMethod == "POST") &&
            (response.StatusCode == 404 && response.SubStatusCode == 13))
        {
            // Clear the response header but do not clear errors and
            // transfer back to requesting page to handle error
            response.ClearHeaders();
            HttpContext.Current.Server.Transfer(request.AppRelativeCurrentExecutionFilePath);
        }
    }

Python, Matplotlib, subplot: How to set the axis range?

Using axes objects is a great approach for this. It helps if you want to interact with multiple figures and sub-plots. To add and manipulate the axes objects directly:

import matplotlib.pyplot as plt
fig = plt.figure(figsize=(12,9))

signal_axes = fig.add_subplot(211)
signal_axes.plot(xs,rawsignal)

fft_axes = fig.add_subplot(212)
fft_axes.set_title("FFT")
fft_axes.set_autoscaley_on(False)
fft_axes.set_ylim([0,1000])
fft = scipy.fft(rawsignal)
fft_axes.plot(abs(fft))

plt.show()

How to set selected index JComboBox by value

Why not take a collection, likely a Map such as a HashMap, and use it as the nucleus of your own combo box model class that implements the ComboBoxModel interface? Then you could access your combo box's items easily via their key Strings rather than ints.

For instance...

import java.util.HashMap;
import java.util.Map;

import javax.swing.ComboBoxModel;
import javax.swing.event.ListDataListener;

public class MyComboModel<K, V>   implements ComboBoxModel {
   private Map<K, V> nucleus = new HashMap<K, V>();

   // ... any constructors that you want would go here

   public void put(K key, V value) {
      nucleus.put(key, value);
   }

   public V get(K key) {
      return nucleus.get(key);
   }

   @Override
   public void addListDataListener(ListDataListener arg0) {
      // TODO Auto-generated method stub

   }

   // ... plus all the other methods required by the interface
}

Undefined class constant 'MYSQL_ATTR_INIT_COMMAND' with pdo

I just tried with PHP 5.2, and that constant seems to exists :

var_dump(PDO::MYSQL_ATTR_INIT_COMMAND);

Gives me :

int 1002


But it seems there is a bug in PHP 5.3, that causes this constant to not exists anymore -- or, at least, not when the mysqlnd driver is used (and it's the one that's configured by default)

I suppose a temporary solution, as suggested on this bug report, could be to directly use the integer 1002 value, instead of the contant...

But note that you should go back to using the constant as soon as possible -- as this makes the code easier to understand.

Http 415 Unsupported Media type error with JSON

Add the HTTP header manager and add in it your API's header names and values. e.g. Content-type, Accept, etc. That will resolve your issue.

Javascript - get array of dates between 2 dates

Function:

  var dates = [],
      currentDate = startDate,
      addDays = function(days) {
        var date = new Date(this.valueOf());
        date.setDate(date.getDate() + days);
        return date;
      };
  while (currentDate <= endDate) {
    dates.push(currentDate);
    currentDate = addDays.call(currentDate, 1);
  }
  return dates;
};

Usage:

var dates = getDatesRange(new Date(2019,01,01), new Date(2019,01,25));                                                                                                           
dates.forEach(function(date) {
  console.log(date);
});

Hope it helps you

How do you tell if caps lock is on using JavaScript?

Here is a custom jquery plugin, using jquery ui, made up of all the good ideas on this page and leverages the tooltip widget. The caps lock message is auto applied all password boxes and requires no changes to your current html.

Custom plug in code...

(function ($) {
    $.fn.capsLockAlert = function () {
        return this.each(function () {
            var capsLockOn = false;
            var t = $(this);
            var updateStatus = function () {
                if (capsLockOn) {
                    t.tooltip('open');
                } else {
                    t.tooltip('close');
                }
            }
            t.tooltip({
                items: "input",
                position: { my: "left top", at: "left bottom+10" },
                open: function (event, ui) {
                    ui.tooltip.css({ "min-width": "100px", "white-space": "nowrap" }).addClass('ui-state-error');
                    if (!capsLockOn) t.tooltip('close');
                },
                content: function () {
                    return $('<p style="white-space: nowrap;"/>')
                        .append($('<span class="ui-icon ui-icon-alert" style="display: inline-block; margin-right: 5px; vertical-align: text-top;" />'))
                        .append('Caps Lock On');
                }
            })
            .off("mouseover mouseout")
            .keydown(function (e) {
                if (e.keyCode !== 20) return;
                capsLockOn = !capsLockOn;
                updateStatus();
            })
            .keypress(function (e) {
                var kc = e.which; //get keycode

                var isUp = (kc >= 65 && kc <= 90) ? true : false; // uppercase
                var isLow = (kc >= 97 && kc <= 122) ? true : false; // lowercase
                if (!isUp && !isLow) return; //This isn't a character effected by caps lock

                // event.shiftKey does not seem to be normalized by jQuery(?) for IE8-
                var isShift = (e.shiftKey) ? e.shiftKey : ((kc === 16) ? true : false); // shift is pressed

                // uppercase w/out shift or lowercase with shift == caps lock
                if ((isUp && !isShift) || (isLow && isShift)) {
                    capsLockOn = true;
                } else {
                    capsLockOn = false;
                }
                updateStatus();
            });
        });
    };
})(jQuery);

Apply to all password elements...

$(function () {
    $(":password").capsLockAlert();
});

What's the difference between jquery.js and jquery.min.js?

They are both the same functionally but the .min one has all unnecessary characters removed in order to make the file size smaller.

Just to point out as well, you are better using the minified version (.min) for your live environment as Google are now checking on page loading times. Having all your JS file minified means they will load faster and will score you more brownie points.

You can get an addon for Mozilla called Page Speed that will look through your site and show you all the .JS files and provide minified versions (amongst other things).

Changing the current working directory in Java?

The smarter/easier thing to do here is to just change your code so that instead of opening the file assuming that it exists in the current working directory (I assume you are doing something like new File("blah.txt"), just build the path to the file yourself.

Let the user pass in the base directory, read it from a config file, fall back to user.dir if the other properties can't be found, etc. But it's a whole lot easier to improve the logic in your program than it is to change how environment variables work.

phpmyadmin logs out after 1440 secs

To set permanently cookie you need to follow some steps

Goto->/etc/phpmyadmin/config.inc.php file

add this code

$cfg['LoginCookieValidity'] = <cookie expiration time in seconds > 

Number to String in a formula field

I believe this is what you're looking for:

Convert Decimal Numbers to Text showing only the non-zero decimals

Especially this line might be helpful:

StringVar text     :=  Totext ( {Your.NumberField} , 6 , ""  )  ;

The first parameter is the decimal to be converted, the second parameter is the number of decimal places and the third parameter is the separator for thousands/millions etc.

Notify ObservableCollection when Item changes

I know it's late, but maybe this helps others. I have created a class NotifyObservableCollection, that solves the problem of missing notification to item itself, when a property of the item changes. The usage is as simple as ObservableCollection.

public class NotifyObservableCollection<T> : ObservableCollection<T> where T : INotifyPropertyChanged
{
    private void Handle(object sender, PropertyChangedEventArgs args)
    {
        OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset, null));
    }

    protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
    {
        if (e.NewItems != null) {
            foreach (object t in e.NewItems) {
                ((T) t).PropertyChanged += Handle;
            }
        }
        if (e.OldItems != null) {
            foreach (object t in e.OldItems) {
                ((T) t).PropertyChanged -= Handle;
            }
        }
        base.OnCollectionChanged(e);
    }

While Items are added or removed the class forwards the items PropertyChanged event to the collections PropertyChanged event.

usage:

public abstract class ParameterBase : INotifyPropertyChanged
{
    protected readonly CultureInfo Ci = new CultureInfo("en-US");
    private string _value;

    public string Value {
        get { return _value; }
        set {
            if (value == _value) return;
            _value = value;
            OnPropertyChanged();
        }
    }
}

public class AItem {
    public NotifyObservableCollection<ParameterBase> Parameters {
        get { return _parameters; }
        set {
            NotifyCollectionChangedEventHandler cceh = (sender, args) => OnPropertyChanged();
            if (_parameters != null) _parameters.CollectionChanged -= cceh;
            _parameters = value;
            //needed for Binding to AItem at xaml directly
            _parameters.CollectionChanged += cceh; 
        }
    }

    public NotifyObservableCollection<ParameterBase> DefaultParameters {
        get { return _defaultParameters; }
        set {
            NotifyCollectionChangedEventHandler cceh = (sender, args) => OnPropertyChanged();
            if (_defaultParameters != null) _defaultParameters.CollectionChanged -= cceh;
            _defaultParameters = value;
            //needed for Binding to AItem at xaml directly
            _defaultParameters.CollectionChanged += cceh;
        }
    }


public class MyViewModel {
    public NotifyObservableCollection<AItem> DataItems { get; set; }
}

If now a property of an item in DataItems changes, the following xaml will get a notification, though it binds to Parameters[0] or to the item itself except to the changing property Value of the item (Converters at Triggers are called reliable on every change).

<DataGrid CanUserAddRows="False" AutoGenerateColumns="False" ItemsSource="{Binding DataItems}">
    <DataGrid.Columns>
        <DataGridTextColumn Binding="{Binding Parameters[0].Value}" Header="P1">
            <DataGridTextColumn.CellStyle>
                <Style TargetType="DataGridCell">
                    <Setter Property="Background" Value="Aqua" />
                    <Style.Triggers>
                        <DataTrigger Value="False">
                            <!-- Bind to Items with changing properties -->
                            <DataTrigger.Binding>
                                <MultiBinding Converter="{StaticResource ParameterCompareConverter}">
                                    <Binding Path="DefaultParameters[0]" />
                                    <Binding Path="Parameters[0]" />
                                </MultiBinding>
                            </DataTrigger.Binding>
                            <Setter Property="Background" Value="DeepPink" />
                        </DataTrigger>
                        <!-- Binds to AItem directly -->
                        <DataTrigger Value="True" Binding="{Binding Converter={StaticResource CheckParametersConverter}}">
                            <Setter Property="FontWeight" Value="ExtraBold" />
                        </DataTrigger>
                    </Style.Triggers>
                </Style>
            </DataGridTextColumn.CellStyle>
        </DataGridTextColumn>

What is the most efficient way to loop through dataframes with pandas?

For sure, the fastest way to iterate over a dataframe is to access the underlying numpy ndarray either via df.values (as you do) or by accessing each column separately df.column_name.values. Since you want to have access to the index too, you can use df.index.values for that.

index = df.index.values
column_of_interest1 = df.column_name1.values
...
column_of_interestk = df.column_namek.values

for i in range(df.shape[0]):
   index_value = index[i]
   ...
   column_value_k = column_of_interest_k[i]

Not pythonic? Sure. But fast.

If you want to squeeze more juice out of the loop you will want to look into cython. Cython will let you gain huge speedups (think 10x-100x). For maximum performance check memory views for cython.

Why Choose Struct Over Class?

In Swift, a new programming pattern has been introduced known as Protocol Oriented Programming.

Creational Pattern:

In swift, Struct is a value types which are automatically cloned. Therefore we get the required behavior to implement the prototype pattern for free.

Whereas classes are the reference type, which is not automatically cloned during the assignment. To implement the prototype pattern, classes must adopt the NSCopying protocol.


Shallow copy duplicates only the reference, that points to those objects whereas deep copy duplicates object’s reference.


Implementing deep copy for each reference type has become a tedious task. If classes include further reference type, we have to implement prototype pattern for each of the references properties. And then we have to actually copy the entire object graph by implementing the NSCopying protocol.

class Contact{
  var firstName:String
  var lastName:String
  var workAddress:Address // Reference type
}

class Address{
   var street:String
   ...
} 

By using structs and enums, we made our code simpler since we don’t have to implement the copy logic.

conflicting types for 'outchar'

It's because you haven't declared outchar before you use it. That means that the compiler will assume it's a function returning an int and taking an undefined number of undefined arguments.

You need to add a prototype pf the function before you use it:

void outchar(char);  /* Prototype (declaration) of a function to be called */  int main(void) {     ... }  void outchar(char ch) {     ... } 

Note the declaration of the main function differs from your code as well. It's actually a part of the official C specification, it must return an int and must take either a void argument or an int and a char** argument.

How to use Spring Boot with MySQL database and JPA?

In the spring boot reference,it said:

When a class doesn’t include a package declaration it is considered to be in the “default package”. The use of the “default package” is generally discouraged, and should be avoided. It can cause particular problems for Spring Boot applications that use @ComponentScan, @EntityScan or @SpringBootApplication annotations, since every class from every jar, will be read.

com
 +- example
     +- myproject
         +- Application.java
         |
         +- domain
         |   +- Customer.java
         |   +- CustomerRepository.java
         |
         +- service
         |   +- CustomerService.java
         |
         +- web
             +- CustomerController.java

In your cases. You must add scanBasePackages in the @SpringBootApplication annotation.just like@SpringBootApplication(scanBasePackages={"domain","contorller"..})

Is there a 'box-shadow-color' property?

Maybe this is new (I am also pretty crap at css3), but I have a page that uses exactly what you suggest:

-moz-box-shadow: 10px 10px 5px #384e69;
-webkit-box-shadow: 10px 10px 5px #384e69;
box-shadow: 10px 10px 5px #384e69;}

.. and it works fine for me (in Chrome at least).

How can I jump to class/method definition in Atom text editor?

This feature has been built-in into Atom editor (see: symbols-view package), but you need to generate ctags symbols file for your project GH-9, GH-20.

To do that, install ctags command (e.g. brew install ctags on macOS), then:

  1. Append, link or copy ctags-config to your ~/.ctags, example on macOS:

    ln -vs "$(find /Applications/Atom.app -name ctags-config -print -quit)" ~/.ctags
    
  2. Go to your project folder and run:

    cd your/project/directory
    ctags -R .
    
  3. Restart Atom editor.


Alternatively you can use symbol-gen package to generate ctags symbols file for your project based on the options found in .ctags file. You can install it from Atom Package Manager by: apm install symbol-gen. Then hit CMD-Alt-G to generate tags file for your project.


After following above, you can use Go To Declaration option from the context menu.

On macOS you can use also use the following keyboard shortcuts:

  • CMD-R to jump to a function/method in the current ,editor
  • Alt-CMD-Down to go to declaration.

How to insert default values in SQL table?

The best way is:

insert your_table
default values

Set the value of an input field

Direct access

If you use ID then you have direct access to input in JS global scope

_x000D_
_x000D_
myInput.value = 'default_value'
_x000D_
<input id="myInput">
_x000D_
_x000D_
_x000D_

How can I convert string date to NSDate?

Below are some string to date format converting options can be usedin swift iOS.

  1. Thursday, Dec 27, 2018 format= EEEE, MMM d, yyyy
  2. 12/27/2018 format= MM/dd/yyyy
  3. 12-27-2018 09:59 format= MM-dd-yyyy HH:mm
  4. Dec 27, 9:59 AM format= MMM d, h:mm a
  5. December 2018 format= MMMM yyyy
  6. Dec 27, 2018 format= MMM d, yyyy
  7. Thu, 27 Dec 2018 09:59:19 +0000 format= E, d MMM yyyy HH:mm:ss Z
  8. 2018-12-27T09:59:19+0000 format= yyyy-MM-dd'T'HH:mm:ssZ
  9. 27.12.18 format= dd.MM.yy
  10. 09:59:19.815 format= HH:mm:ss.SSS

Getting the Username from the HKEY_USERS values

You can use the command PSGetSid from Microsoft's SysInternals team.

Download URL: http://technet.microsoft.com/en-gb/sysinternals/bb897417.aspx

Usage:

psgetsid [\\computer[,computer[,...] | @file] [-u username [-p password]]] [account|SID]
-u  Specifies optional user name for login to remote computer.
-p  Specifies optional password for user name. If you omit this you will be prompted to enter a hidden password.
Account PsGetSid will report the SID for the specified user account rather than the computer.
SID PsGetSid will report the account for the specified SID.
Computer    Direct PsGetSid to perform the command on the remote computer or computers specified. If you omit the computer name PsGetSid runs the command on the local system, and if you specify a wildcard (\\*), PsGetSid runs the command on all computers in the current domain.
@file   PsGetSid will execute the command on each of the computers listed in the file.

Example:

psgetsid S-1-5-21-583907252-682003330-839522115-63941

NB:

  • Where the user is a domain/AD(LDAP) user, running this on any computer on the domain should give the same results.
  • Where the user is local to the machine the command should either be run on that machine, or you should specify the computer via the optional parameter.

Update

If you use PowerShell, the following may be useful for resolving any AD users listed:

#create a drive for HKEY USERS:
New-PSDrive -PSProvider Registry -Name HKU -Root HKEY_USERS -ErrorAction SilentlyContinue

#List all immediate subfolders
#where they're a folder (not a key)
#and they's an SID (i.e. exclude .DEFAULT and SID_Classes entries)
#return the SID
#and return the related AD entry (should one exist).
Get-ChildItem -Path 'HKU:\' `
| ?{($_.PSIsContainer -eq $true) `
-and ($_.PSChildName -match '^S-[\d-]+$')} `
| select @{N='SID';E={$_.PSChildName}} `
, @{N='Name';E={Get-ADUser $_.PSChildName | select -expand Name}}

You could also refine the SID filter further to only pull back those SIDs which will resolve to an AD account if you wished; more on the SID structure here: https://technet.microsoft.com/en-us/library/cc962011.aspx

Call Python function from MATLAB

I had a similar requirement on my system and this was my solution:

In MATLAB there is a function called perl.m, which allows you to call perl scripts from MATLAB. Depending on which version you are using it will be located somewhere like

C:\Program Files\MATLAB\R2008a\toolbox\matlab\general\perl.m

Create a copy called python.m, a quick search and replace of perl with python, double check the command path it sets up to point to your installation of python. You should now be able to run python scripts from MATLAB.

Example

A simple squared function in python saved as "sqd.py", naturally if I was doing this properly I'd have a few checks in testing input arguments, valid numbers etc.

import sys

def squared(x):
    y = x * x
    return y

if __name__ == '__main__':
    x = float(sys.argv[1])
    sys.stdout.write(str(squared(x)))

Then in MATLAB

>> r=python('sqd.py','3.5')
r =
12.25
>> r=python('sqd.py','5')
r =
25.0
>>

What does `dword ptr` mean?

The dword ptr part is called a size directive. This page explains them, but it wasn't possible to direct-link to the correct section.

Basically, it means "the size of the target operand is 32 bits", so this will bitwise-AND the 32-bit value at the address computed by taking the contents of the ebp register and subtracting four with 0.

How do search engines deal with AngularJS applications?

Update May 2014

Google crawlers now executes javascript - you can use the Google Webmaster Tools to better understand how your sites are rendered by Google.

Original answer
If you want to optimize your app for search engines there is unfortunately no way around serving a pre-rendered version to the crawler. You can read more about Google's recommendations for ajax and javascript-heavy sites here.

If this is an option I'd recommend reading this article about how to do SEO for Angular with server-side rendering.

I’m not sure what the crawler does when it encounters custom tags.

how to insert a new line character in a string to PrintStream then use a scanner to re-read the file

The linefeed character \n is not the line separator in certain operating systems (such as windows, where it's "\r\n") - my suggestion is that you use \r\n instead, then it'll both see the line-break with only \n and \r\n, I've never had any problems using it.

Also, you should look into using a StringBuilder instead of concatenating the String in the while-loop at BookCatalog.toString(), it is a lot more effective. For instance:

public String toString() {
        BookNode current = front;
        StringBuilder sb = new StringBuilder();
        while (current!=null){
            sb.append(current.getData().toString()+"\r\n ");
            current = current.getNext();
        }
        return sb.toString();
}

nginx- duplicate default server error

In my case junk files from editor caused the problem. I had a config as below:

#...
http {
 # ...
 include ../sites/*;
}

In the ../sites directory initially I had a default.config file. However, by mistake I saved duplicate files as default.config.save and default.config.save.1. Removing them resolved the issue.

Does List<T> guarantee insertion order?

This is the code I have for moving an item down one place in a list:

if (this.folderImages.SelectedIndex > -1 && this.folderImages.SelectedIndex < this.folderImages.Items.Count - 1)
{
    string imageName = this.folderImages.SelectedItem as string;
    int index = this.folderImages.SelectedIndex;

    this.folderImages.Items.RemoveAt(index);
    this.folderImages.Items.Insert(index + 1, imageName);
    this.folderImages.SelectedIndex = index + 1;
 }

and this for moving it one place up:

if (this.folderImages.SelectedIndex > 0)
{
    string imageName = this.folderImages.SelectedItem as string;
    int index = this.folderImages.SelectedIndex;

    this.folderImages.Items.RemoveAt(index);
    this.folderImages.Items.Insert(index - 1, imageName);
    this.folderImages.SelectedIndex = index - 1;
}

folderImages is a ListBox of course so the list is a ListBox.ObjectCollection, not a List<T>, but it does inherit from IList so it should behave the same. Does this help?

Of course the former only works if the selected item is not the last item in the list and the latter if the selected item is not the first item.

powershell 2.0 try catch how to access the exception

Try something like this:

try {
    $w = New-Object net.WebClient
    $d = $w.downloadString('http://foo')
}
catch [Net.WebException] {
    Write-Host $_.Exception.ToString()
}

The exception is in the $_ variable. You might explore $_ like this:

try {
    $w = New-Object net.WebClient
    $d = $w.downloadString('http://foo')
}
catch [Net.WebException] {
    $_ | fl * -Force
}

I think it will give you all the info you need.

My rule: if there is some data that is not displayed, try to use -force.

What does "-ne" mean in bash?

"not equal" So in this case, $RESULT is tested to not be equal to zero.

However, the test is done numerically, not alphabetically:

n1 -ne n2     True if the integers n1 and n2 are not algebraically equal.

compared to:

s1 != s2      True if the strings s1 and s2 are not identical.

jQuery .find() on data from .ajax() call is returning "[object Object]" instead of div

You might have to do something like

var content= (typeof response.d) == 'string' ? eval('(' + response.d + ')') : response.d

then you should be able to use

result = $(content).find("#result")

How to use color picker (eye dropper)?

Currently, the eyedropper tool is not working in my version of Chrome (as described above), though it worked for me in the past. I hear it is being updated in the latest version of Chrome.

However, I'm able to grab colors easily in Firefox.

  1. Open page in Firefox
  2. Hamburger Menu -> Web Developer -> Eyedropper
  3. Drag eyedropper tool over the image... Click.
    Color is copied to your clipboard, and eyedropper tool goes away.
  4. Paste color code

In case you cannot get the eyedropper tool to work in Chrome, this is a good work around.
I also find it easier to access :-)

How to clear radio button in Javascript?

Wouldn't a better alternative be to just add a third button ("neither") that will give the same result as none selected?

How to append elements at the end of ArrayList in Java?

Here is the syntax, along with some other methods you might find useful:

    //add to the end of the list
    stringList.add(random);

    //add to the beginning of the list
    stringList.add(0,  random);

    //replace the element at index 4 with random
    stringList.set(4, random);

    //remove the element at index 5
    stringList.remove(5);

    //remove all elements from the list
    stringList.clear();

jQuery javascript regex Replace <br> with \n

a cheap and nasty would be:

jQuery("#myDiv").html().replace("<br>", "\n").replace("<br />", "\n")

EDIT

jQuery("#myTextArea").val(
    jQuery("#myDiv").html()
        .replace(/\<br\>/g, "\n")
        .replace(/\<br \/\>/g, "\n")
);

Also created a jsfiddle if needed: http://jsfiddle.net/2D3xx/

How to set div's height in css and html

<div style="height: 100px;"> </div>

OR

<div id="foo"/> and set the style as #foo { height: 100px; }
<div class="bar"/> and set the style as .bar{ height: 100px;  }

Package opencv was not found in the pkg-config search path

with opencv 4.0;

  • add -DOPENCV_GENERATE_PKGCONFIG=ON to build arguments
  • pkg-config --cflags --libs opencv4 instead of opencv

TypeError: ObjectId('') is not JSON serializable

For those who need to return the data thru Jsonify with Flask:

cursor = db.collection.find()
data = []
for doc in cursor:
    doc['_id'] = str(doc['_id']) # This does the trick!
    data.append(doc)
return jsonify(data)

Difference of two date time in sql server

Please check below trick to find the date difference between two dates

 DATEDIFF(DAY,ordr.DocDate,RDR1.U_ProgDate) datedifff

where you can change according your requirement as you want difference of days or month or year or time.

How can I convert string to datetime with format specification in JavaScript?

Use new Date(dateString) if your string is compatible with Date.parse(). If your format is incompatible (I think it is), you have to parse the string yourself (should be easy with regular expressions) and create a new Date object with explicit values for year, month, date, hour, minute and second.

How to hide the title bar for an Activity in XML with existing custom theme

For AppCompat, following solution worked for me:

Add new theme style with no action bar in your styles.xml and set parent="Theme.AppCompat.NoActionBar".

<style name="SplashTheme" parent="Theme.AppCompat.NoActionBar">

    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimary</item>
    <item name="colorAccent">@color/colorAccent</item>
    <item name="android:windowBackground">@color/colorPrimary</item>

</style>


Now implement the same theme style to your splash screen activity in androidManifest.xml

<activity
        android:name=".ActivityName"
        android:theme="@style/SplashTheme"> // apply splash them here 

        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
</activity>

Here is result:

enter image description here

List of ANSI color escape sequences

The ANSI escape sequences you're looking for are the Select Graphic Rendition subset. All of these have the form

\033[XXXm

where XXX is a series of semicolon-separated parameters.

To say, make text red, bold, and underlined (we'll discuss many other options below) in C you might write:

printf("\033[31;1;4mHello\033[0m");

In C++ you'd use

std::cout<<"\033[31;1;4mHello\033[0m";

In Python3 you'd use

print("\033[31;1;4mHello\033[0m")

and in Bash you'd use

echo -e "\033[31;1;4mHello\033[0m"

where the first part makes the text red (31), bold (1), underlined (4) and the last part clears all this (0).

As described in the table below, there are a large number of text properties you can set, such as boldness, font, underlining, &c. (Isn't it silly that StackOverflow doesn't allow you to put proper tables in answers?)

Font Effects

Code Effect Note
0 Reset / Normal all attributes off
1 Bold or increased intensity
2 Faint (decreased intensity) Not widely supported.
3 Italic Not widely supported. Sometimes treated as inverse.
4 Underline
5 Slow Blink less than 150 per minute
6 Rapid Blink MS-DOS ANSI.SYS; 150+ per minute; not widely supported
7 [[reverse video]] swap foreground and background colors
8 Conceal Not widely supported.
9 Crossed-out Characters legible, but marked for deletion. Not widely supported.
10 Primary(default) font
11–19 Alternate font Select alternate font n-10
20 Fraktur hardly ever supported
21 Bold off or Double Underline Bold off not widely supported; double underline hardly ever supported.
22 Normal color or intensity Neither bold nor faint
23 Not italic, not Fraktur
24 Underline off Not singly or doubly underlined
25 Blink off
27 Inverse off
28 Reveal conceal off
29 Not crossed out
30–37 Set foreground color See color table below
38 Set foreground color Next arguments are 5;<n> or 2;<r>;<g>;<b>, see below
39 Default foreground color implementation defined (according to standard)
40–47 Set background color See color table below
48 Set background color Next arguments are 5;<n> or 2;<r>;<g>;<b>, see below
49 Default background color implementation defined (according to standard)
51 Framed
52 Encircled
53 Overlined
54 Not framed or encircled
55 Not overlined
60 ideogram underline hardly ever supported
61 ideogram double underline hardly ever supported
62 ideogram overline hardly ever supported
63 ideogram double overline hardly ever supported
64 ideogram stress marking hardly ever supported
65 ideogram attributes off reset the effects of all of 60-64
90–97 Set bright foreground color aixterm (not in standard)
100–107 Set bright background color aixterm (not in standard)

2-bit Colours

You've got this already!

4-bit Colours

The standards implementing terminal colours began with limited (4-bit) options. The table below lists the RGB values of the background and foreground colours used for these by a variety of terminal emulators:

Table of ANSI colours implemented by various terminal emulators

Using the above, you can make red text on a green background (but why?) using:

\033[31;42m

11 Colours (An Interlude)

In their book "Basic Color Terms: Their Universality and Evolution", Brent Berlin and Paul Kay used data collected from twenty different languages from a range of language families to identify eleven possible basic color categories: white, black, red, green, yellow, blue, brown, purple, pink, orange, and gray.

Berlin and Kay found that, in languages with fewer than the maximum eleven color categories, the colors followed a specific evolutionary pattern. This pattern is as follows:

  1. All languages contain terms for black (cool colours) and white (bright colours).
  2. If a language contains three terms, then it contains a term for red.
  3. If a language contains four terms, then it contains a term for either green or yellow (but not both).
  4. If a language contains five terms, then it contains terms for both green and yellow.
  5. If a language contains six terms, then it contains a term for blue.
  6. If a language contains seven terms, then it contains a term for brown.
  7. If a language contains eight or more terms, then it contains terms for purple, pink, orange or gray.

This may be why story Beowulf only contains the colours black, white, and red. It may also be why the Bible does not contain the colour blue. Homer's Odyssey contains black almost 200 times and white about 100 times. Red appears 15 times, while yellow and green appear only 10 times. (More information here)

Differences between languages are also interesting: note the profusion of distinct colour words used by English vs. Chinese. However, digging deeper into these languages shows that each uses colour in distinct ways. (More information)

Chinese vs English colour names. Image adapted from "muyueh.com"

Generally speaking, the naming, use, and grouping of colours in human languages is fascinating. Now, back to the show.

8-bit (256) colours

Technology advanced, and tables of 256 pre-selected colours became available, as shown below.

256-bit colour mode for ANSI escape sequences

Using these above, you can make pink text like so:

\033[38;5;206m     #That is, \033[38;5;<FG COLOR>m

And make an early-morning blue background using

\033[48;5;57m      #That is, \033[48;5;<BG COLOR>m

And, of course, you can combine these:

\033[38;5;206;48;5;57m

The 8-bit colours are arranged like so:

0x00-0x07:  standard colors (same as the 4-bit colours)
0x08-0x0F:  high intensity colors
0x10-0xE7:  6 × 6 × 6 cube (216 colors): 16 + 36 × r + 6 × g + b (0 = r, g, b = 5)
0xE8-0xFF:  grayscale from black to white in 24 steps

ALL THE COLOURS

Now we are living in the future, and the full RGB spectrum is available using:

\033[38;2;<r>;<g>;<b>m     #Select RGB foreground color
\033[48;2;<r>;<g>;<b>m     #Select RGB background color

So you can put pinkish text on a brownish background using

\033[38;2;255;82;197;48;2;155;106;0mHello

Support for "true color" terminals is listed here.

Much of the above is drawn from the Wikipedia page "ANSI escape code".

A Handy Script to Remind Yourself

Since I'm often in the position of trying to remember what colours are what, I have a handy script called: ~/bin/ansi_colours:

#!/usr/bin/python

print "\\033[XXm"

for i in range(30,37+1):
    print "\033[%dm%d\t\t\033[%dm%d" % (i,i,i+60,i+60);

print "\033[39m\\033[39m - Reset colour"
print "\\033[2K - Clear Line"
print "\\033[<L>;<C>H OR \\033[<L>;<C>f puts the cursor at line L and column C."
print "\\033[<N>A Move the cursor up N lines"
print "\\033[<N>B Move the cursor down N lines"
print "\\033[<N>C Move the cursor forward N columns"
print "\\033[<N>D Move the cursor backward N columns"
print "\\033[2J Clear the screen, move to (0,0)"
print "\\033[K Erase to end of line"
print "\\033[s Save cursor position"
print "\\033[u Restore cursor position"
print " "
print "\\033[4m  Underline on"
print "\\033[24m Underline off"
print "\\033[1m  Bold on"
print "\\033[21m Bold off"

This prints

Simple ANSI colours

How to use pull to refresh in Swift?

Pull to refresh is built in iOS. You could do this in swift like

var refreshControl = UIRefreshControl()

override func viewDidLoad() {
   super.viewDidLoad()

   refreshControl.attributedTitle = NSAttributedString(string: "Pull to refresh")
   refreshControl.addTarget(self, action: #selector(self.refresh(_:)), for: .valueChanged)
   tableView.addSubview(refreshControl) // not required when using UITableViewController
}

@objc func refresh(_ sender: AnyObject) {
   // Code to refresh table view  
}

At some point you could end refreshing.

refreshControl.endRefreshing()

Practical uses for the "internal" keyword in C#

There are cases when it makes sense to make members of classes internal. One example could be if you want to control how the classes are instantiated; let's say you provide some sort of factory for creating instances of the class. You can make the constructor internal, so that the factory (that resides in the same assembly) can create instances of the class, but code outside of that assembly can't.

However, I can't see any point with making classes or members internal without specific reasons, just as little as it makes sense to make them public, or private without specific reasons.

Update TensorFlow

for a specific version

pip install --upgrade tensorflow==2.2

How to test an Internet connection with bash?

Ping was designed to do exactly what you're looking to do. However, if the site blocks ICMP echo, then you can always do the telnet to port 80 of some site, wget, or curl.

Yarn install command error No such file or directory: 'install'

I had the same issue on Ubuntu 17.04.

This solution worked for me:

sudo apt remove cmdtest
sudo apt remove yarn
curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -
echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list
sudo apt-get update
sudo apt-get install yarn -y

then

yarn install

result:

yarn install v1.3.2
warning You are using Node "6.0.0" which is not supported and may encounter bugs or unexpected behaviour. Yarn supports the following server range: "^4.8.0 || ^5.7.0 || ^6.2.2 || >=8.0.0"
info No lockfile found.
[1/4] Resolving packages...
[2/4] Fetching packages...
[3/4] Linking dependencies...
[4/4] Building fresh packages...

info Lockfile not saved, no dependencies.
Done in 0.20s.

Hope that it will help you.

How to get the return value from a thread in python?

I stole kindall's answer and cleaned it up just a little bit.

The key part is adding *args and **kwargs to join() in order to handle the timeout

class threadWithReturn(Thread):
    def __init__(self, *args, **kwargs):
        super(threadWithReturn, self).__init__(*args, **kwargs)

        self._return = None

    def run(self):
        if self._Thread__target is not None:
            self._return = self._Thread__target(*self._Thread__args, **self._Thread__kwargs)

    def join(self, *args, **kwargs):
        super(threadWithReturn, self).join(*args, **kwargs)

        return self._return

UPDATED ANSWER BELOW

This is my most popularly upvoted answer, so I decided to update with code that will run on both py2 and py3.

Additionally, I see many answers to this question that show a lack of comprehension regarding Thread.join(). Some completely fail to handle the timeout arg. But there is also a corner-case that you should be aware of regarding instances when you have (1) a target function that can return None and (2) you also pass the timeout arg to join(). Please see "TEST 4" to understand this corner case.

ThreadWithReturn class that works with py2 and py3:

import sys
from threading import Thread
from builtins import super    # https://stackoverflow.com/a/30159479

if sys.version_info >= (3, 0):
    _thread_target_key = '_target'
    _thread_args_key = '_args'
    _thread_kwargs_key = '_kwargs'
else:
    _thread_target_key = '_Thread__target'
    _thread_args_key = '_Thread__args'
    _thread_kwargs_key = '_Thread__kwargs'

class ThreadWithReturn(Thread):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self._return = None

    def run(self):
        target = getattr(self, _thread_target_key)
        if not target is None:
            self._return = target(
                *getattr(self, _thread_args_key),
                **getattr(self, _thread_kwargs_key)
            )

    def join(self, *args, **kwargs):
        super().join(*args, **kwargs)
        return self._return

Some sample tests are shown below:

import time, random

# TEST TARGET FUNCTION
def giveMe(arg, seconds=None):
    if not seconds is None:
        time.sleep(seconds)
    return arg

# TEST 1
my_thread = ThreadWithReturn(target=giveMe, args=('stringy',))
my_thread.start()
returned = my_thread.join()
# (returned == 'stringy')

# TEST 2
my_thread = ThreadWithReturn(target=giveMe, args=(None,))
my_thread.start()
returned = my_thread.join()
# (returned is None)

# TEST 3
my_thread = ThreadWithReturn(target=giveMe, args=('stringy',), kwargs={'seconds': 5})
my_thread.start()
returned = my_thread.join(timeout=2)
# (returned is None) # because join() timed out before giveMe() finished

# TEST 4
my_thread = ThreadWithReturn(target=giveMe, args=(None,), kwargs={'seconds': 5})
my_thread.start()
returned = my_thread.join(timeout=random.randint(1, 10))

Can you identify the corner-case that we may possibly encounter with TEST 4?

The problem is that we expect giveMe() to return None (see TEST 2), but we also expect join() to return None if it times out.

returned is None means either:

(1) that's what giveMe() returned, or

(2) join() timed out

This example is trivial since we know that giveMe() will always return None. But in real-world instance (where the target may legitimately return None or something else) we'd want to explicitly check for what happened.

Below is how to address this corner-case:

# TEST 4
my_thread = ThreadWithReturn(target=giveMe, args=(None,), kwargs={'seconds': 5})
my_thread.start()
returned = my_thread.join(timeout=random.randint(1, 10))

if my_thread.isAlive():
    # returned is None because join() timed out
    # this also means that giveMe() is still running in the background
    pass
    # handle this based on your app's logic
else:
    # join() is finished, and so is giveMe()
    # BUT we could also be in a race condition, so we need to update returned, just in case
    returned = my_thread.join()

How to use C++ in Go

As of go1.2+, cgo automatically incorporates and compiles C++ code:

http://golang.org/doc/go1.2#cgo_and_cpp

Grant Select on all Tables Owned By Specific User

yes, its possible, run this command:

lets say you have user called thoko

grant select any table, insert any table, delete any table, update any table to thoko;

note: worked on oracle database

jQuery datepicker years shown

Adding to what @Shog9 posted, you can also restrict dates individually in the beforeShowDay: callback function.

You supply a function that takes a date and returns a boolean array:

"$(".selector").datepicker({ beforeShowDay: nationalDays}) 
natDays = [[1, 26, 'au'], [2, 6, 'nz'], [3, 17, 'ie'], [4, 27, 'za'], 
[5, 25, 'ar'], [6, 6, 'se'], [7, 4, 'us'], [8, 17, 'id'], [9, 7, 
'br'], [10, 1, 'cn'], [11, 22, 'lb'], [12, 12, 'ke']]; 
function nationalDays(date) { 
    for (i = 0; i < natDays.length; i++) { 
      if (date.getMonth() == natDays[i][0] - 1 && date.getDate() == 
natDays[i][1]) { 
        return [false, natDays[i][2] + '_day']; 
      } 
    } 
  return [true, '']; 
} 

Is there a way to view past mysql queries with phpmyadmin?

Yes, you can log queries to a special phpMyAdmin DB table.

See SQL_history.

Uncaught TypeError: data.push is not a function

make sure you push into an Array only and if their is error like Uncaught TypeError: data.push is not a function** then check for type of data you can do this by consol.log(data) hope this will help

I do not understand how execlp() works in Linux

this prototype:

  int execlp(const char *file, const char *arg, ...);

Says that execlp ìs a variable argument function. It takes 2 const char *. The rest of the arguments, if any, are the additional arguments to hand over to program we want to run - also char * - all these are C strings (and the last argument must be a NULL pointer)

So, the file argument is the path name of an executable file to be executed. arg is the string we want to appear as argv[0] in the executable. By convention, argv[0] is just the file name of the executable, normally it's set to the same as file.

The ... are now the additional arguments to give to the executable.

Say you run this from a commandline/shell:

$ ls

That'd be execlp("ls", "ls", (char *)NULL); Or if you run

$ ls -l /

That'd be execlp("ls", "ls", "-l", "/", (char *)NULL);

So on to execlp("/bin/sh", ..., "ls -l /bin/??", ...);

Here you are going to the shell, /bin/sh , and you're giving the shell a command to execute. That command is "ls -l /bin/??". You can run that manually from a commandline/shell:

 $ ls -l /bin/??

Now, how do you run a shell and tell it to execute a command ? You open up the documentation/man page for your shell and read it.

What you want to run is:

$ /bin/sh -c "ls -l /bin/??"

This becomes

  execlp("/bin/sh","/bin/sh", "-c", "ls -l /bin/??", (char *)NULL);

Side note: The /bin/?? is doing pattern matching, this pattern matching is done by the shell, and it expands to all files under /bin/ with 2 characters. If you simply did

  execlp("ls","ls", "-l", "/bin/??", (char *)NULL);

Probably nothing would happen (unless there's a file actually named /bin/??) as there's no shell that interprets and expands /bin/??

Gem Command not found

check that rvm is a function type rvm | head -1

Window.Open with PDF stream instead of PDF location

Note: I have verified this in the latest version of IE, and other browsers like Mozilla and Chrome and this works for me. Hope it works for others as well.

if (data == "" || data == undefined) {
    alert("Falied to open PDF.");
} else { //For IE using atob convert base64 encoded data to byte array
    if (window.navigator && window.navigator.msSaveOrOpenBlob) {
        var byteCharacters = atob(data);
        var byteNumbers = new Array(byteCharacters.length);
        for (var i = 0; i < byteCharacters.length; i++) {
            byteNumbers[i] = byteCharacters.charCodeAt(i);
        }
        var byteArray = new Uint8Array(byteNumbers);
        var blob = new Blob([byteArray], {
            type: 'application/pdf'
        });
        window.navigator.msSaveOrOpenBlob(blob, fileName);
    } else { // Directly use base 64 encoded data for rest browsers (not IE)
        var base64EncodedPDF = data;
        var dataURI = "data:application/pdf;base64," + base64EncodedPDF;
        window.open(dataURI, '_blank');
    }

}

Case-insensitive search in Rails model

Assuming that you use mysql, you could use fields that are not case sensitive: http://dev.mysql.com/doc/refman/5.0/en/case-sensitivity.html

Foreach value from POST from form

If your post keys have to be parsed and the keys are sequences with data, you can try this:

Post data example: Storeitem|14=data14

foreach($_POST as $key => $value){
    $key=Filterdata($key); $value=Filterdata($value);
    echo($key."=".$value."<br>");
}

then you can use strpos to isolate the end of the key separating the number from the key.

What is the standard naming convention for html/css ids and classes?

tl;dr;

There is no one true answer. You can pick one of the many out there, or create your own standards based on what makes sense, depending upon who you're working with. And it is 100% dependent upon the platform.


Original Post

Just one more alternative standard to consider:

<div id="id_name" class="class-name"></div>

And in your script:

var variableName = $("#id_name .class-name");

This just uses a camelCase, under_score, and hyphen-ation respectively for variables, ids, and classes. I've read about this standard on a couple of different websites. Although a little redundant in css/jquery selectors, redundancies make it easier to catch errors. eg: If you see .unknown_name or #unknownName in your CSS file, you know you need to figure out what that's actually referring to.


UPDATE 2019

(Hyphens are called 'kebab-case', underscores are called 'snake_case', and then you have 'TitleCase', 'pascalCase')

I personally dislike hyphens. I originally posted this as one alternative (because the rules are simple). However, Hyphens make selection shortcuts very difficult (double click, ctrl/option + left/right, and ctrl/cmd+D in vsCode. Also, class names and file names are the only place where hyphens work, because they're almost always in quotes or in css, etc. But the shortcut thing still applies.

In addition to variables, class names, and ids, you also want to look at file name conventions. And Git Branches.

My office's coding group actually had a meeting a month or two ago to discuss how we were going to name things. For git branches, we couldn't decide between 321-the_issue_description or 321_the-issue-description. (I wanted 321_theIssueDescription, but my coworkers didn't like that.)

An Example, to demonstrate working with other peoples' standards...

Vue.js does have a standard. Actually they have two alternate standards for several of their items. I dislike both of their versions for filenames. They recommend either "/path/kebab-case.vue" or "/path/TitleCase.Vue". The former is harder to rename, unless you're specifically trying to rename part of it. The latter is not good for cross-platform compatibility. I would prefer "/path/snake_case.vue". However, when working with other people or existing projects, it's important to follow whatever standard was already laid out. Therefore I go with kebab-case for filenames in Vue, even though I'll totally complain about it. Because not following that means changing a lot of files that vue-cli sets up.

Run a JAR file from the command line and specify classpath

You can do these in unix shell:

java -cp MyJar.jar:lib/* com.somepackage.subpackage.Main

You can do these in windows powershell:

java -cp "MyJar.jar;lib\*" com.somepackage.subpackage.Main

Firefox and SSL: sec_error_unknown_issuer

To answer the non-reproducability aspect of the question - Firefox automatically imports intermediate certificates into its certificate store. So if you've previously visited a site which has used the same Intermediate Certificate using a correctly configured certificate chain then Firefox will store that Certificate so you will not see the problem when you visit a site that has an incorrectly configured chain using the same Intermediate certificate.

You can check this in Firefox's Certificate Manager (Options->Privacy&Security->View Certificates...) where you can see all stored certificates. Under the 'Security Device' Column you can check where a certificate has come from - automatically/manually imported certificates will appear as from 'Software Security Device' as opposed to the 'Builtin Object Token', which are the default set installed with Firefox. You can delete/Distrust any specific certificates and test again.

Best practice for instantiating a new Android Fragment

If Android decides to recreate your Fragment later, it's going to call the no-argument constructor of your fragment. So overloading the constructor is not a solution.

With that being said, the way to pass stuff to your Fragment so that they are available after a Fragment is recreated by Android is to pass a bundle to the setArguments method.

So, for example, if we wanted to pass an integer to the fragment we would use something like:

public static MyFragment newInstance(int someInt) {
    MyFragment myFragment = new MyFragment();

    Bundle args = new Bundle();
    args.putInt("someInt", someInt);
    myFragment.setArguments(args);

    return myFragment;
}

And later in the Fragment onCreate() you can access that integer by using:

getArguments().getInt("someInt", 0);

This Bundle will be available even if the Fragment is somehow recreated by Android.

Also note: setArguments can only be called before the Fragment is attached to the Activity.

This approach is also documented in the android developer reference: https://developer.android.com/reference/android/app/Fragment.html

JavaScript for detecting browser language preference

DanSingerman has a very good solution for this question.

The only reliable source for the language is in the HTTP-request header. So you need a server-side script to reply the request-header or at least the Accept-Language field back to you.

Here is a very simple Node.js server which should be compatible with DanSingermans jQuery plugin.

var http = require('http');
http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end(JSON.stringify(req.headers));
}).listen(80,'0.0.0.0');

Generate list of all possible permutations of a string

Though this doesn't answer your question exactly, here's one way to generate every permutation of the letters from a number of strings of the same length: eg, if your words were "coffee", "joomla" and "moodle", you can expect output like "coodle", "joodee", "joffle", etc.

Basically, the number of combinations is the (number of words) to the power of (number of letters per word). So, choose a random number between 0 and the number of combinations - 1, convert that number to base (number of words), then use each digit of that number as the indicator for which word to take the next letter from.

eg: in the above example. 3 words, 6 letters = 729 combinations. Choose a random number: 465. Convert to base 3: 122020. Take the first letter from word 1, 2nd from word 2, 3rd from word 2, 4th from word 0... and you get... "joofle".

If you wanted all the permutations, just loop from 0 to 728. Of course, if you're just choosing one random value, a much simpler less-confusing way would be to loop over the letters. This method lets you avoid recursion, should you want all the permutations, plus it makes you look like you know Maths(tm)!

If the number of combinations is excessive, you can break it up into a series of smaller words and concatenate them at the end.

batch/bat to copy folder and content at once

For Folder Copy You can Use

robocopy C:\Source D:\Destination /E

For File Copy

copy D:\Sourcefile.txt D:\backup\Destinationfile.txt /Y 

Delete file in some folder last modify date more than some day

forfiles -p "D:\FolderPath" -s -m *.[Filetype eg-->.txt] -d -[Numberof dates] -c "cmd /c del @PATH"

And you can Shedule task in windows perform this task automatically in specific time.

Change background color of selected item on a ListView

View updateview;// above oncreate method
listView.setChoiceMode(ListView.CHOICE_MODE_SINGLE);


listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
         if (updateview != null) 
            updateview.setBackgroundColor(Color.TRANSPARENT);
         updateview = view;   

         view.setBackgroundColor(Color.CYAN);
     }
});

Indexes of all occurrences of character in a string

With Java9, one can make use of the iterate(int seed, IntPredicate hasNext,IntUnaryOperator next) as follows:-

List<Integer> indexes = IntStream
          .iterate(word.indexOf(c), index -> index >= 0, index -> word.indexOf(c, index + 1))
          .boxed()
          .collect(Collectors.toList());
System.out.printlnt(indexes);

How to scroll the page when a modal dialog is longer than the screen?

position:fixed implies that, well, the modal window will remain fixed relative to the viewpoint. I agree with your assessment that it's appropriate in this scenario, with that in mind why don'y you add a scrollbar to the modal window itself?

If so, correct max-height and overflow properties should do the trick.

How to convert Varchar to Double in sql?

This might be more desirable, that is use float instead

SELECT fullName, CAST(totalBal as float) totalBal FROM client_info ORDER BY totalBal DESC

elasticsearch bool query combine must with OR

$filterQuery = $this->queryFactory->create(QueryInterface::TYPE_BOOL, ['must' => $queries,'should'=>$queriesGeo]);

In must you need to add the query condition array which you want to work with AND and in should you need to add the query condition which you want to work with OR.

You can check this: https://github.com/Smile-SA/elasticsuite/issues/972

What is the largest possible heap size with a 64-bit JVM?

For a 64-bit JVM running in a 64-bit OS on a 64-bit machine, is there any limit besides the theoretical limit of 2^64 bytes or 16 exabytes?

You also have to take hardware limits into account. While pointers may be 64bit current CPUs can only address a less than 2^64 bytes worth of virtual memory.

With uncompressed pointers the hotspot JVM needs a continuous chunk of virtual address space for its heap. So the second hurdle after hardware is the operating system providing such a large chunk, not all OSes support this.

And the third one is practicality. Even if you can have that much virtual memory it does not mean the CPUs support that much physical memory, and without physical memory you will end up swapping, which will adversely affect the performance of the JVM because the GCs generally have to touch a large fraction of the heap.

As other answers mention compressed oops: By bumping the object alignment higher than 8 bytes the limits with compressed oops can be increased beyond 32GB

typedef fixed length array

Here's a short example of why typedef array can be confusingly inconsistent. The other answers provide a workaround.

#include <stdio.h>
typedef char type24[3];

int func(type24 a) {
        type24 b;
        printf("sizeof(a) is %zu\n",sizeof(a));
        printf("sizeof(b) is %zu\n",sizeof(b));
        return 0;
}

int main(void) {
        type24 a;
        return func(a);
}

This produces the output

sizeof(a) is 8
sizeof(b) is 3

because type24 as a parameter is a pointer. (In C, arrays are always passed as pointers.) The gcc8 compiler will issue a warning by default, thankfully.

Multiple Buttons' OnClickListener() android

I find that using a long if/else chain (or switch), in addition to the list of findViewById(btn).setOnClickListener(this) is ugly. how about creating new View.OnlickListeners with override, in-line:

findViewById(R.id.signInButton).setOnClickListener(new View.OnClickListener()
    { @Override public void onClick(View v) { signIn(); }});
findViewById(R.id.signOutButton).setOnClickListener(new View.OnClickListener()
    { @Override public void onClick(View v) { signOut(); }});
findViewById(R.id.keyTestButton).setOnClickListener(new View.OnClickListener()
    { @Override public void onClick(View v) { decryptThisTest(); }});
findViewById(R.id.getBkTicksButton).setOnClickListener(new View.OnClickListener()
    { @Override public void onClick(View v) { getBookTickers(); }});
findViewById(R.id.getBalsButton).setOnClickListener(new View.OnClickListener()
    { @Override public void onClick(View v) { getBalances(); }});

Mongoose (mongodb) batch insert?

Mongoose 4.4.0 now supports bulk insert

Mongoose 4.4.0 introduces --true-- bulk insert with the model method .insertMany(). It is way faster than looping on .create() or providing it with an array.

Usage:

var rawDocuments = [/* ... */];

Book.insertMany(rawDocuments)
    .then(function(mongooseDocuments) {
         /* ... */
    })
    .catch(function(err) {
        /* Error handling */
    });

Or

Book.insertMany(rawDocuments, function (err, mongooseDocuments) { /* Your callback function... */ });

You can track it on:

Find text string using jQuery?

Take a look at highlight (jQuery plugin).

Why does NULL = NULL evaluate to false in SQL server

How old is Frank? I don't know (null).

How old is Shirley? I don't know (null).

Are Frank and Shirley the same age?

Correct answer should be "I don't know" (null), not "no", as Frank and Shirley might be the same age, we simply don't know.

How to insert a text at the beginning of a file?

To add a line to the top of the file:

sed -i '1iText to add\'

How to get current class name including package name in Java?

use this.getClass().getName() to get packageName.className and use this.getClass().getSimpleName() to get only class name

Export multiple classes in ES6 modules

Hope this helps:

// Export (file name: my-functions.js)
export const MyFunction1 = () => {}
export const MyFunction2 = () => {}
export const MyFunction3 = () => {}

// if using `eslint` (airbnb) then you will see warning, so do this:
const MyFunction1 = () => {}
const MyFunction2 = () => {}
const MyFunction3 = () => {}

export {MyFunction1, MyFunction2, MyFunction3};

// Import
import * as myFns from "./my-functions";

myFns.MyFunction1();
myFns.MyFunction2();
myFns.MyFunction3();


// OR Import it as Destructured
import { MyFunction1, MyFunction2, MyFunction3 } from "./my-functions";

// AND you can use it like below with brackets (Parentheses) if it's a function 
// AND without brackets if it's not function (eg. variables, Objects or Arrays)  
MyFunction1();
MyFunction2();

How to open child forms positioned within MDI parent in VB.NET?

   Private Sub FileMenu_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) handles FileMenu.Click

    Form1.MdiParent = Me
    Form1.Dock = DockStyle.Fill
    Form1.Show()
End Sub

Passing string parameter in JavaScript function

Rename your variable name to myname, bacause name is a generic property of window and is not writable in the same window.

And replace

onclick='myfunction(\''" + name + "'\')'

With

onclick='myfunction(myname)'

Working example:

_x000D_
_x000D_
var myname = "Mathew";_x000D_
document.write('<button id="button" type="button" onclick="myfunction(myname);">click</button>');_x000D_
function myfunction(name) {_x000D_
    alert(name);_x000D_
}
_x000D_
_x000D_
_x000D_

How to strip HTML tags from a string in SQL Server?

Derived from @Goner Doug answer, with a few things updated:
- using REPLACE where possible
- conversion of predefined entities like &eacute; (I chose the ones I needed :-)
- some conversion of list tags <ul> and <li>

ALTER FUNCTION [dbo].[udf_StripHTML]
--by Patrick Honorez --- www.idevlop.com
--inspired by http://stackoverflow.com/questions/457701/best-way-to-strip-html-tags-from-a-string-in-sql-server/39253602#39253602
(
@HTMLText varchar(MAX)
)
RETURNS varchar(MAX)
AS
BEGIN
DECLARE @Start  int
DECLARE @End    int
DECLARE @Length int

set @HTMLText = replace(@htmlText, '<br>',CHAR(13) + CHAR(10))
set @HTMLText = replace(@htmlText, '<br/>',CHAR(13) + CHAR(10))
set @HTMLText = replace(@htmlText, '<br />',CHAR(13) + CHAR(10))
set @HTMLText = replace(@htmlText, '<li>','- ')
set @HTMLText = replace(@htmlText, '</li>',CHAR(13) + CHAR(10))

set @HTMLText = replace(@htmlText, '&rsquo;' collate Latin1_General_CS_AS, ''''  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&quot;' collate Latin1_General_CS_AS, '"'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&amp;' collate Latin1_General_CS_AS, '&'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&euro;' collate Latin1_General_CS_AS, '€'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&lt;' collate Latin1_General_CS_AS, '<'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&gt;' collate Latin1_General_CS_AS, '>'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&oelig;' collate Latin1_General_CS_AS, 'oe'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&nbsp;' collate Latin1_General_CS_AS, ' '  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&copy;' collate Latin1_General_CS_AS, '©'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&laquo;' collate Latin1_General_CS_AS, '«'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&reg;' collate Latin1_General_CS_AS, '®'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&plusmn;' collate Latin1_General_CS_AS, '±'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&sup2;' collate Latin1_General_CS_AS, '²'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&sup3;' collate Latin1_General_CS_AS, '³'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&micro;' collate Latin1_General_CS_AS, 'µ'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&middot;' collate Latin1_General_CS_AS, '·'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&ordm;' collate Latin1_General_CS_AS, 'º'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&raquo;' collate Latin1_General_CS_AS, '»'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&frac14;' collate Latin1_General_CS_AS, '¼'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&frac12;' collate Latin1_General_CS_AS, '½'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&frac34;' collate Latin1_General_CS_AS, '¾'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&Aelig' collate Latin1_General_CS_AS, 'Æ'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&Ccedil;' collate Latin1_General_CS_AS, 'Ç'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&Egrave;' collate Latin1_General_CS_AS, 'È'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&Eacute;' collate Latin1_General_CS_AS, 'É'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&Ecirc;' collate Latin1_General_CS_AS, 'Ê'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&Ouml;' collate Latin1_General_CS_AS, 'Ö'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&agrave;' collate Latin1_General_CS_AS, 'à'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&acirc;' collate Latin1_General_CS_AS, 'â'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&auml;' collate Latin1_General_CS_AS, 'ä'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&aelig;' collate Latin1_General_CS_AS, 'æ'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&ccedil;' collate Latin1_General_CS_AS, 'ç'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&egrave;' collate Latin1_General_CS_AS, 'è'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&eacute;' collate Latin1_General_CS_AS, 'é'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&ecirc;' collate Latin1_General_CS_AS, 'ê'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&euml;' collate Latin1_General_CS_AS, 'ë'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&icirc;' collate Latin1_General_CS_AS, 'î'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&ocirc;' collate Latin1_General_CS_AS, 'ô'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&ouml;' collate Latin1_General_CS_AS, 'ö'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&divide;' collate Latin1_General_CS_AS, '÷'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&oslash;' collate Latin1_General_CS_AS, 'ø'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&ugrave;' collate Latin1_General_CS_AS, 'ù'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&uacute;' collate Latin1_General_CS_AS, 'ú'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&ucirc;' collate Latin1_General_CS_AS, 'û'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&uuml;' collate Latin1_General_CS_AS, 'ü'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&quot;' collate Latin1_General_CS_AS, '"'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&amp;' collate Latin1_General_CS_AS, '&'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&lsaquo;' collate Latin1_General_CS_AS, '<'  collate Latin1_General_CS_AS)
set @HTMLText = replace(@htmlText, '&rsaquo;' collate Latin1_General_CS_AS, '>'  collate Latin1_General_CS_AS)


-- Remove anything between <STYLE> tags
SET @Start = CHARINDEX('<STYLE', @HTMLText)
SET @End = CHARINDEX('</STYLE>', @HTMLText, CHARINDEX('<', @HTMLText)) + 7
SET @Length = (@End - @Start) + 1

WHILE (@Start > 0 AND @End > 0 AND @Length > 0) BEGIN
SET @HTMLText = STUFF(@HTMLText, @Start, @Length, '')
SET @Start = CHARINDEX('<STYLE', @HTMLText)
SET @End = CHARINDEX('</STYLE>', @HTMLText, CHARINDEX('</STYLE>', @HTMLText)) + 7
SET @Length = (@End - @Start) + 1
END

-- Remove anything between <whatever> tags
SET @Start = CHARINDEX('<', @HTMLText)
SET @End = CHARINDEX('>', @HTMLText, CHARINDEX('<', @HTMLText))
SET @Length = (@End - @Start) + 1

WHILE (@Start > 0 AND @End > 0 AND @Length > 0) BEGIN
SET @HTMLText = STUFF(@HTMLText, @Start, @Length, '')
SET @Start = CHARINDEX('<', @HTMLText)
SET @End = CHARINDEX('>', @HTMLText, CHARINDEX('<', @HTMLText))
SET @Length = (@End - @Start) + 1
END

RETURN LTRIM(RTRIM(@HTMLText))

END

Printing all properties in a Javascript Object

What about this:

var txt="";
var nyc = {
    fullName: "New York City",
    mayor: "Michael Bloomberg",
    population: 8000000,
    boroughs: 5
};

for (var x in nyc){
    txt += nyc[x];
}

How to center an iframe horizontally?

If you can't access the iFrame class then add below css to wrapper div.

<div style="display: flex; justify-content: center;">
    <iframe></iframe>
</div>

Difference in make_shared and normal shared_ptr in C++

I see one problem with std::make_shared, it doesn't support private/protected constructors

Convert seconds to HH-MM-SS with JavaScript?

There are lots of options of solve this problem, and obvious there are good option suggested about, But I wants to add one more optimized code here

function formatSeconds(sec) {
     return [(sec / 3600), ((sec % 3600) / 60), ((sec % 3600) % 60)]
            .map(v => v < 10 ? "0" + parseInt(v) : parseInt(v))
            .filter((i, j) => i !== "00" || j > 0)
            .join(":");
}

if you don't wants formatted zero with less then 10 number, you can use

function formatSeconds(sec) {
  return parseInt(sec / 3600) + ':' + parseInt((sec % 3600) / 60) + ':' + parseInt((sec % 3600) % 60);

}

Sample Code http://fiddly.org/1c476/1

C# Convert List<string> to Dictionary<string, string>

You can use:

var dictionary = myList.ToDictionary(x => x);

PHP function overloading

<?php

    class abs
    {
        public function volume($arg1=null, $arg2=null, $arg3=null)
        {   
            if($arg1 == null && $arg2 == null && $arg3 == null)
        {
            echo "function has no arguments. <br>";
        }

        else if($arg1 != null && $arg2 != null && $arg3 != null)
            {
            $volume=$arg1*$arg2*$arg3;
            echo "volume of a cuboid ".$volume ."<br>";
            }
            else if($arg1 != null && $arg2 != null)
            {
            $area=$arg1*$arg2;
            echo "area of square  = " .$area ."<br>";
            }
            else if($arg1 != null)
            {
            $volume=$arg1*$arg1*$arg1; 
            echo "volume of a cube = ".$volume ."<br>";
            }


        }


    }

    $obj=new abs();
    echo "For no arguments. <br>";
    $obj->volume();
    echo "For one arguments. <br>";
    $obj->volume(3);
    echo "For two arguments. <br>";
    $obj->volume(3,4);
    echo "For three arguments. <br>";
    $obj->volume(3,4,5);
    ?>

Find string between two substrings

source='your token _here0@df and maybe _here1@df or maybe _here2@df'
start_sep='_'
end_sep='@df'
result=[]
tmp=source.split(start_sep)
for par in tmp:
  if end_sep in par:
    result.append(par.split(end_sep)[0])

print result

must show: here0, here1, here2

the regex is better but it will require additional lib an you may want to go for python only

Passing variables, creating instances, self, The mechanics and usage of classes: need explanation

class Foo          (object):
    # ^class name  #^ inherits from object

    bar = "Bar" #Class attribute.

    def __init__(self):
        #        #^ The first variable is the class instance in methods.  
        #        #  This is called "self" by convention, but could be any name you want.
        #^ double underscore (dunder) methods are usually special.  This one 
        #  gets called immediately after a new instance is created.

        self.variable = "Foo" #instance attribute.
        print self.variable, self.bar  #<---self.bar references class attribute
        self.bar = " Bar is now Baz"   #<---self.bar is now an instance attribute
        print self.variable, self.bar  

    def method(self, arg1, arg2):
        #This method has arguments.  You would call it like this:  instance.method(1, 2)
        print "in method (args):", arg1, arg2
        print "in method (attributes):", self.variable, self.bar


a = Foo() # this calls __init__ (indirectly), output:
                 # Foo bar
                 # Foo  Bar is now Baz
print a.variable # Foo
a.variable = "bar"
a.method(1, 2) # output:
               # in method (args): 1 2
               # in method (attributes): bar  Bar is now Baz
Foo.method(a, 1, 2) #<--- Same as a.method(1, 2).  This makes it a little more explicit what the argument "self" actually is.

class Bar(object):
    def __init__(self, arg):
        self.arg = arg
        self.Foo = Foo()

b = Bar(a)
b.arg.variable = "something"
print a.variable # something
print b.Foo.variable # Foo

Create Word Document using PHP in Linux

<?php
function fWriteFile($sFileName,$sFileContent="No Data",$ROOT)
    {
        $word = new COM("word.application") or die("Unable to instantiate Word");
        //bring it to front
        $word->Visible = 1;
        //open an empty document
        $word->Documents->Add();
        //do some weird stuff
        $word->Selection->TypeText($sFileContent);
        $word->Documents[1]->SaveAs($ROOT."/".$sFileName.".doc");
        //closing word
        $word->Quit();
        //free the object
        $word = null;
        return $sFileName;
    }
?>



<?php
$PATH_ROOT=dirname(__FILE__);
$Return ="<table>";
$Return .="<tr><td>Row[0]</td></tr>";
 $Return .="<tr><td>Row[1]</td></tr>";
$sReturn .="</table>";
fWriteFile("test",$Return,$PATH_ROOT);
?> 

What's the best practice for putting multiple projects in a git repository?

While most people will tell you to just use multiple repositories, I feel it's worth mentioning there are other solutions.

Solution 1

A single repository can contain multiple independent branches, called orphan branches. Orphan branches are completely separate from each other; they do not share histories.

git checkout --orphan BRANCHNAME

This creates a new branch, unrelated to your current branch. Each project should be in its own orphaned branch.

Now for whatever reason, git needs a bit of cleanup after an orphan checkout.

rm .git/index
rm -r *

Make sure everything is committed before deleting

Once the orphan branch is clean, you can use it normally.

Solution 2

Avoid all the hassle of orphan branches. Create two independent repositories, and push them to the same remote. Just use different branch names for each repo.

# repo 1
git push origin master:master-1

# repo 2
git push origin master:master-2

I want to declare an empty array in java and then I want do update it but the code is not working

You need to give the array a size:

public static void main(String args[])
{
    int array[] = new int[4];
    int number = 5, i = 0,j = 0;
    while (i<4){
        array[i]=number;
        i=i+1;
    }
    while (j<4){
        System.out.println(array[j]);
        j++;
    }
}

Is it possible to set an object to null?

You can set any pointer to NULL, though NULL is simply defined as 0 in C++:

myObject *foo = NULL;

Also note that NULL is defined if you include standard headers, but is not built into the language itself. If NULL is undefined, you can use 0 instead, or include this:

#ifndef NULL
#define NULL 0
#endif

As an aside, if you really want to set an object, not a pointer, to NULL, you can read about the Null Object Pattern.

Why do we usually use || over |? What is the difference?

The basic difference between them is that | first converts the values to binary then performs the bit wise or operation. Meanwhile, || does not convert the data into binary and just performs the or expression on it's original state.

int two = -2; int four = -4;
result = two | four; // bitwise OR example

System.out.println(Integer.toBinaryString(two));
System.out.println(Integer.toBinaryString(four));
System.out.println(Integer.toBinaryString(result));

Output:
11111111111111111111111111111110
11111111111111111111111111111100
11111111111111111111111111111110

Read more: http://javarevisited.blogspot.com/2015/01/difference-between-bitwsie-and-logical.html#ixzz45PCxdQhk

Tomcat: LifecycleException when deploying

I also faced this due to Tomcat version mismatching! According to the documentation, the default tomcat version of Grails 4.0.x is tomcat 8 but in the server that I was using had the tomcat version of 9.0.31!

in the build.gradle file I changed compile "org.springframework.boot:spring-boot-starter-tomcat" to provided "org.springframework.boot:spring-boot-starter-tomcat" and added/modified the cache plugin to compile "org.grails.plugins:cache", { exclude group: "org.codehaus.groovy", module: "groovy-all" } under dependencies block! [Cache plugin comes with groovy-all 2.1]

It worked like a charm! Strangely, this did not cause any problems when running the app with command grails run-app

Is there a job scheduler library for node.js?

I am the auhor of node-runnr . It have a very simple approach to create job. Also its very easy and clear to declare time and interval. For example, to execute a job at every 10min 20sec,

Runnr.addIntervalJob('10:20', function(){...}, 'myjob')

To do a job at 10am and 3pm daily,

Runnr.addDailyJob(['10:0:0', '15:0:0'], function(){...}, 'myjob')

Its that simple. For further detail: https://github.com/Saquib764/node-runnr

Find row number of matching value

For your first method change ws.Range("A") to ws.Range("A:A") which will search the entirety of column a, like so:

Sub Find_Bingo()

        Dim wb As Workbook
        Dim ws As Worksheet
        Dim FoundCell As Range
        Set wb = ActiveWorkbook
        Set ws = ActiveSheet

            Const WHAT_TO_FIND As String = "Bingo"

            Set FoundCell = ws.Range("A:A").Find(What:=WHAT_TO_FIND)
            If Not FoundCell Is Nothing Then
                MsgBox (WHAT_TO_FIND & " found in row: " & FoundCell.Row)
            Else
                MsgBox (WHAT_TO_FIND & " not found")
            End If
End Sub

For your second method, you are using Bingo as a variable instead of a string literal. This is a good example of why I add Option Explicit to the top of all of my code modules, as when you try to run the code it will direct you to this "variable" which is undefined and not intended to be a variable at all.

Additionally, when you are using With...End With you need a period . before you reference Cells, so Cells should be .Cells. This mimics the normal qualifying behavior (i.e. Sheet1.Cells.Find..)

Change Bingo to "Bingo" and change Cells to .Cells

With Sheet1
        Set FoundCell = .Cells.Find(What:="Bingo", After:=.Cells(1, 1), _
        LookIn:=xlValues, lookat:=xlPart, SearchOrder:=xlByRows, _
        SearchDirection:=xlNext, MatchCase:=False, SearchFormat:=False)
    End With

If Not FoundCell Is Nothing Then
        MsgBox ("""Bingo"" found in row " & FoundCell.Row)
Else
        MsgBox ("Bingo not found")
End If

Update

In my

With Sheet1
    .....
End With

The Sheet1 refers to a worksheet's code name, not the name of the worksheet itself. For example, say I open a new blank Excel workbook. The default worksheet is just Sheet1. I can refer to that in code either with the code name of Sheet1 or I can refer to it with the index of Sheets("Sheet1"). The advantage to using a codename is that it does not change if you change the name of the worksheet.

Continuing this example, let's say I renamed Sheet1 to Data. Using Sheet1 would continue to work, as the code name doesn't change, but now using Sheets("Sheet1") would return an error and that syntax must be updated to the new name of the sheet, so it would need to be Sheets("Data").

In the VB Editor you would see something like this:

code object explorer example

Notice how, even though I changed the name to Data, there is still a Sheet1 to the left. That is what I mean by codename.

The Data worksheet can be referenced in two ways:

Debug.Print Sheet1.Name
Debug.Print Sheets("Data").Name

Both should return Data

More discussion on worksheet code names can be found here.

unique() for more than one variable

This is an addition to Josh's answer.

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

Example:

library(data.table)

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

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

# set the key to all columns
setkey(dt)

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

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

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

unique combination of V1 and V2

Converting Float to Dollars and Cents

In Python 3.x and 2.7, you can simply do this:

>>> '${:,.2f}'.format(1234.5)
'$1,234.50'

The :, adds a comma as a thousands separator, and the .2f limits the string to two decimal places (or adds enough zeroes to get to 2 decimal places, as the case may be) at the end.

TypeError: only length-1 arrays can be converted to Python scalars while plot showing

dataframe['column'].squeeze() should solve this. It basically changes the dataframe column to a list.

Convert string to BigDecimal in java

You are storing 135.69 as String in currency. But instead of passing variable currency, you are again passing 135.69(double value) into new BigDecimal(). So you are seeing a lot of numbers in the output. If you pass the currency variable, your output will be 135.69

How do you get AngularJS to bind to the title attribute of an A tag?

It looks like ng-attr is a new directive in AngularJS 1.1.4 that you can possibly use in this case.

<!-- example -->
<a ng-attr-title="{{product.shortDesc}}"></a>

However, if you stay with 1.0.7, you can probably write a custom directive to mirror the effect.

How can I convert a string to a number in Perl?

This is a simple solution:

Example 1

my $var1 = "123abc";
print $var1 + 0;

Result

123

Example 2

my $var2 = "abc123";
print $var2 + 0;

Result

0

using facebook sdk in Android studio

*Gradle Repository for the Facebook SDK.

dependencies {
    compile 'com.facebook.android:facebook-android-sdk:4.4.0'
}

Search for the latest version facebook sdk

How to update a record using sequelize for node?

If Model.update statement does not work for you, you can try like this:

try{ 
    await sequelize.query('update posts set param=:param where conditionparam=:conditionparam', {replacements: {param: 'parameter', conditionparam:'condition'}, type: QueryTypes.UPDATE})
}
catch(err){
    console.log(err)
}

Vue.js img src concatenate variable and text

In another case I'm able to use template literal ES6 with backticks, so for yours could be set as:

<img v-bind:src="`${imgPreUrl()}img/logo.png`">

DLL Load Library - Error Code 126

This can also happen when you're trying to load a DLL and that in turn needs another DLL which cannot be not found.

Confused about stdin, stdout and stderr?

stderr will not do IO Cache buffering so if our application need to print critical message info (some errors ,exceptions) to console or to file use it where as use stdout to print general log info as it use IO Cache buffering there is a chance that before writing our messages to file application may close ,leaving debugging complex

Using BigDecimal to work with currencies

1) If you are limited to the double precision, one reason to use BigDecimals is to realize operations with the BigDecimals created from the doubles.

2) The BigDecimal consists of an arbitrary precision integer unscaled value and a non-negative 32-bit integer scale, while the double wraps a value of the primitive type double in an object. An object of type Double contains a single field whose type is double

3) It should make no difference

You should have no difficulties with the $ and precision. One way to do it is using System.out.printf

How to use bitmask?

Briefly bitmask helps to manipulate position of multiple values. There is a good example here ;

Bitflags are a method of storing multiple values, which are not mutually exclusive, in one variable. You've probably seen them before. Each flag is a bit position which can be set on or off. You then have a bunch of bitmasks #defined for each bit position so you can easily manipulate it:

    #define LOG_ERRORS            1  // 2^0, bit 0
    #define LOG_WARNINGS          2  // 2^1, bit 1
    #define LOG_NOTICES           4  // 2^2, bit 2
    #define LOG_INCOMING          8  // 2^3, bit 3
    #define LOG_OUTGOING         16  // 2^4, bit 4
    #define LOG_LOOPBACK         32  // and so on...

// Only 6 flags/bits used, so a char is fine
unsigned char flags;

// initialising the flags
// note that assigning a value will clobber any other flags, so you
// should generally only use the = operator when initialising vars.
flags = LOG_ERRORS;
// sets to 1 i.e. bit 0

//initialising to multiple values with OR (|)
flags = LOG_ERRORS | LOG_WARNINGS | LOG_INCOMING;
// sets to 1 + 2 + 8 i.e. bits 0, 1 and 3

// setting one flag on, leaving the rest untouched
// OR bitmask with the current value
flags |= LOG_INCOMING;

// testing for a flag
// AND with the bitmask before testing with ==
if ((flags & LOG_WARNINGS) == LOG_WARNINGS)
   ...

// testing for multiple flags
// as above, OR the bitmasks
if ((flags & (LOG_INCOMING | LOG_OUTGOING))
         == (LOG_INCOMING | LOG_OUTGOING))
   ...

// removing a flag, leaving the rest untouched
// AND with the inverse (NOT) of the bitmask
flags &= ~LOG_OUTGOING;

// toggling a flag, leaving the rest untouched
flags ^= LOG_LOOPBACK;



**

WARNING: DO NOT use the equality operator (i.e. bitflags == bitmask) for testing if a flag is set - that expression will only be true if that flag is set and all others are unset. To test for a single flag you need to use & and == :

**

if (flags == LOG_WARNINGS) //DON'T DO THIS
   ...
if ((flags & LOG_WARNINGS) == LOG_WARNINGS) // The right way
   ...
if ((flags & (LOG_INCOMING | LOG_OUTGOING)) // Test for multiple flags set
         == (LOG_INCOMING | LOG_OUTGOING))
   ...

You can also search C++ Triks

Chrome blocks different origin requests

Direct Javascript calls between frames and/or windows are only allowed if they conform to the same-origin policy. If your window and iframe share a common parent domain you can set document.domain to "domain lower") one or both such that they can communicate. Otherwise you'll need to look into something like the postMessage() API.

Accept function as parameter in PHP

Just code it like this:

function example($anon) {
  $anon();
}

example(function(){
  // some codes here
});

it would be great if you could invent something like this (inspired by Laravel Illuminate):

Object::method("param_1", function($param){
  $param->something();
});

How to use sbt from behind proxy?

To provide one answer that will work for all Windows-users:

Add the following to your sbtconfig.txt (C:\Program Files (x86)\sbt\conf)

-Dhttp.proxyHost=XXXXXXX -Dhttp.proxyPort=YYYY -Dhttp.proxySet=true -Dhttps.proxyHost=XXXXXXX -Dhttps.proxyPort=YYYY -Dhttps.proxySet=true

Replace both XXXXXXX with your proxyHost, and both YYYY with your proxyPort.

If you get the error "Could not find or load main class" you need to set your JAVA_HOME:

set JAVA_HOME=C:\Progra~1\Java\jdkxxxxxx

When on 64-bit windows, use:

Progra~1 = 'Program Files'

Progra~2 = 'Program Files(x86)'

How do I make a simple crawler in PHP?

I created a small class to grab data from the provided url, then extract html elements of your choice. The class makes use of CURL and DOMDocument.

php class:

class crawler {


   public static $timeout = 2;
   public static $agent   = 'Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)';


   public static function http_request($url) {
      $ch = curl_init();
      curl_setopt($ch, CURLOPT_URL,            $url);
      curl_setopt($ch, CURLOPT_USERAGENT,      self::$agent);
      curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, self::$timeout);
      curl_setopt($ch, CURLOPT_TIMEOUT,        self::$timeout);
      curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
      $response = curl_exec($ch);
      curl_close($ch);
      return $response;
   }


   public static function strip_whitespace($data) {
      $data = preg_replace('/\s+/', ' ', $data);
      return trim($data);
   }


   public static function extract_elements($tag, $data) {
      $response = array();
      $dom      = new DOMDocument;
      @$dom->loadHTML($data);
      foreach ( $dom->getElementsByTagName($tag) as $index => $element ) {
         $response[$index]['text'] = self::strip_whitespace($element->nodeValue);
         foreach ( $element->attributes as $attribute ) {
            $response[$index]['attributes'][strtolower($attribute->nodeName)] = self::strip_whitespace($attribute->nodeValue);
         }
      }
      return $response;
   }


}

example usage:

$data  = crawler::http_request('https://stackoverflow.com/questions/2313107/how-do-i-make-a-simple-crawler-in-php');
$links = crawler::extract_elements('a', $data);
if ( count($links) > 0 ) {
   file_put_contents('links.json', json_encode($links, JSON_PRETTY_PRINT));
}

example response:

[
    {
        "text": "Stack Overflow",
        "attributes": {
            "href": "https:\/\/stackoverflow.com",
            "class": "-logo js-gps-track",
            "data-gps-track": "top_nav.click({is_current:false, location:2, destination:8})"
        }
    },
    {
        "text": "Questions",
        "attributes": {
            "id": "nav-questions",
            "href": "\/questions",
            "class": "-link js-gps-track",
            "data-gps-track": "top_nav.click({is_current:true, location:2, destination:1})"
        }
    },
    {
        "text": "Developer Jobs",
        "attributes": {
            "id": "nav-jobs",
            "href": "\/jobs?med=site-ui&ref=jobs-tab",
            "class": "-link js-gps-track",
            "data-gps-track": "top_nav.click({is_current:false, location:2, destination:6})"
        }
    }
]

List of tuples to dictionary

With dict comprehension:

h = {k:v for k,v in l}

Determining 32 vs 64 bit in C++

Unfortunately there is no cross platform macro which defines 32 / 64 bit across the major compilers. I've found the most effective way to do this is the following.

First I pick my own representation. I prefer ENVIRONMENT64 / ENVIRONMENT32. Then I find out what all of the major compilers use for determining if it's a 64 bit environment or not and use that to set my variables.

// Check windows
#if _WIN32 || _WIN64
#if _WIN64
#define ENVIRONMENT64
#else
#define ENVIRONMENT32
#endif
#endif

// Check GCC
#if __GNUC__
#if __x86_64__ || __ppc64__
#define ENVIRONMENT64
#else
#define ENVIRONMENT32
#endif
#endif

Another easier route is to simply set these variables from the compiler command line.

How to define custom sort function in javascript?

or shorter

_x000D_
_x000D_
function sortBy(field) {_x000D_
  return function(a, b) {_x000D_
    return (a[field] > b[field]) - (a[field] < b[field])_x000D_
  };_x000D_
}_x000D_
_x000D_
let myArray = [_x000D_
    {tabid: 6237, url: 'https://reddit.com/r/znation'},_x000D_
    {tabid: 8430, url: 'https://reddit.com/r/soccer'},_x000D_
    {tabid: 1400, url: 'https://reddit.com/r/askreddit'},_x000D_
    {tabid: 3620, url: 'https://reddit.com/r/tacobell'},_x000D_
    {tabid: 5753, url: 'https://reddit.com/r/reddevils'},_x000D_
]_x000D_
_x000D_
myArray.sort(sortBy('url'));_x000D_
console.log(myArray);
_x000D_
_x000D_
_x000D_

How to insert newline in string literal?

If I understand the question: Couple "\r\n" to get that new line below in a textbox. My example worked -

   string s1 = comboBox1.Text;     // s1 is the variable assigned to box 1, etc.
   string s2 = comboBox2.Text;

   string both = s1 + "\r\n" + s2;
   textBox1.Text = both;

A typical answer could be s1 s2 in the text box using defined type style.

Changing the sign of a number in PHP?

I think Gumbo's answer is just fine. Some people prefer this fancy expression that does the same thing:

$int = (($int > 0) ? -$int : $int);

EDIT: Apparently you are looking for a function that will make negatives positive as well. I think these answers are the simplest:

/* I am not proposing you actually use functions called
   "makeNegative" and "makePositive"; I am just presenting
   the most direct solution in the form of two clearly named
   functions. */
function makeNegative($num) { return -abs($num); }
function makePositive($num) { return abs($num); }

MySQL JDBC Driver 5.1.33 - Time Zone Issue

You can use the MySQL connector in the Maven dependency,

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.14</version>
</dependency>

Then you need the set the right parameters in the application.properties file,

spring.datasource.url=jdbc:mysql://localhost:3306/UserReward?useUnicode=true&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC
spring.datasource.username=testuser
spring.datasource.password=testpassword
# MySQL driver
spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.jpa.database-platform=org.hibernate.dialect.MySQL5Dialect

Vertically align an image inside a div with responsive height

I came across this thread in search of a solution that:

  • uses 100% of the given image's width
  • keeps the image aspect ratio
  • keeps the image vertically aligned to the middle
  • works in browsers that do not fully support flex

Testing some of the solutions posted above I didn't find one to meet all of this criteria, so I put together this simple one which might be useful for other people needing to do the same:

_x000D_
_x000D_
.container {_x000D_
  width: 30%;_x000D_
  float: left;_x000D_
  border: 1px solid turquoise;_x000D_
  margin-right: 3px;_x000D_
  margin-top: 3px;_x000D_
}_x000D_
_x000D_
.container:last-of-kind {_x000D_
  margin-right: 0px;_x000D_
}_x000D_
_x000D_
.image-container {_x000D_
  position: relative;_x000D_
  overflow: hidden;_x000D_
  padding-bottom: 70%;_x000D_
  /* this is the desired aspect ratio */_x000D_
  width: 100%;_x000D_
}_x000D_
_x000D_
.image-container img {_x000D_
  position: absolute;_x000D_
  /* the following 3 properties center the image on the vertical axis */_x000D_
  top: 0;_x000D_
  bottom: 0;_x000D_
  margin: auto;_x000D_
  /* uses image at 100% width (also meaning it's horizontally center) */_x000D_
  width: 100%;_x000D_
}
_x000D_
<div class="container">_x000D_
  <div class="image-container">_x000D_
    <img src="http://placehold.it/800x800" class="img-responsive">_x000D_
  </div>_x000D_
</div>_x000D_
_x000D_
<div class="container">_x000D_
  <div class="image-container">_x000D_
    <img src="http://placehold.it/800x800" class="img-responsive">_x000D_
  </div>_x000D_
</div>_x000D_
_x000D_
<div class="container">_x000D_
  <div class="image-container">_x000D_
    <img src="http://placehold.it/800x800" class="img-responsive">_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Working example on JSFiddle

Ordering by the order of values in a SQL IN() clause

Give this a shot:

SELECT name, description, ...
WHERE id IN
    (SELECT id FROM table1 WHERE...)
ORDER BY
    (SELECT display_order FROM table1 WHERE...),
    (SELECT name FROM table1 WHERE...)

The WHEREs will probably take a little tweaking to get the correlated subqueries working properly, but the basic principle should be sound.

In-place edits with sed on OS X

This creates backup files. E.g. sed -i -e 's/hello/hello world/' testfile for me, creates a backup file, testfile-e, in the same dir.

Only variable references should be returned by reference - Codeigniter

Edit filename: core/Common.php, line number: 257

Before

return $_config[0] =& $config; 

After

$_config[0] =& $config;
return $_config[0]; 

Update

Added by NikiC

In PHP assignment expressions always return the assigned value. So $_config[0] =& $config returns $config - but not the variable itself, but a copy of its value. And returning a reference to a temporary value wouldn't be particularly useful (changing it wouldn't do anything).

Update

This fix has been merged into CI 2.2.1 (https://github.com/bcit-ci/CodeIgniter/commit/69b02d0f0bc46e914bed1604cfbd9bf74286b2e3). It's better to upgrade rather than modifying core framework files.

REST API error return good practices

A great resource to pick the correct HTTP error code for your API: http://www.codetinkerer.com/2015/12/04/choosing-an-http-status-code.html

An excerpt from the article:

Where to start:

enter image description here

2XX/3XX:

enter image description here

4XX:

enter image description here

5XX:

enter image description here

In Django, how do I check if a user is in a certain group?

I have done it the following way. Seems inefficient but I had no other way in my mind:

@login_required
def list_track(request):

usergroup = request.user.groups.values_list('name', flat=True).first()
if usergroup in 'appAdmin':
    tracks = QuestionTrack.objects.order_by('pk')
    return render(request, 'cmit/appadmin/list_track.html', {'tracks': tracks})

else:
    return HttpResponseRedirect('/cmit/loggedin')