Programs & Examples On #Constraintexception

How to use a different version of python during NPM install?

set python to python2.7 before running npm install

Linux:

export PYTHON=python2.7

Windows:

set PYTHON=python2.7

Exception : mockito wanted but not invoked, Actually there were zero interactions with this mock

@Jk1's answer is fine, but Mockito also allows for more succinct injection using annotations:

@InjectMocks MyClass myClass; //@InjectMocks automatically instantiates too
@Mock MyInterface myInterface

But regardless of which method you use, the annotations are not being processed (not even your @Mock) unless you somehow call the static MockitoAnnotation.initMocks() or annotate the class with @RunWith(MockitoJUnitRunner.class).

Multiple INNER JOIN SQL ACCESS

Thanks HansUp for your answer, it is very helpful and it works!

I found three patterns working in Access, yours is the best, because it works in all cases.

  • INNER JOIN, your variant. I will call it "closed set pattern". It is possible to join more than two tables to the same table with good performance only with this pattern.

    SELECT C_Name, cr.P_FirstName+" "+cr.P_SurName AS ClassRepresentativ, cr2.P_FirstName+" "+cr2.P_SurName AS ClassRepresentativ2nd
    FROM
         ((class
           INNER JOIN person AS cr 
           ON class.C_P_ClassRep=cr.P_Nr
         )
         INNER JOIN person AS cr2
         ON class.C_P_ClassRep2nd=cr2.P_Nr
      )
    

    ;

  • INNER JOIN "chained-set pattern"

    SELECT C_Name, cr.P_FirstName+" "+cr.P_SurName AS ClassRepresentativ, cr2.P_FirstName+" "+cr2.P_SurName AS ClassRepresentativ2nd
    FROM person AS cr
    INNER JOIN ( class 
       INNER JOIN ( person AS cr2
       ) ON class.C_P_ClassRep2nd=cr2.P_Nr
    ) ON class.C_P_ClassRep=cr.P_Nr
    ;
    
  • CROSS JOIN with WHERE

    SELECT C_Name, cr.P_FirstName+" "+cr.P_SurName AS ClassRepresentativ, cr2.P_FirstName+" "+cr2.P_SurName AS ClassRepresentativ2nd
    FROM class, person AS cr, person AS cr2
    WHERE class.C_P_ClassRep=cr.P_Nr AND class.C_P_ClassRep2nd=cr2.P_Nr
    ;
    

mkdir's "-p" option

Note that -p is an argument to the mkdir command specifically, not the whole of Unix. Every command can have whatever arguments it needs.

In this case it means "parents", meaning mkdir will create a directory and any parents that don't already exist.

VBA copy cells value and format

This page from Microsoft's Excel VBA documentation helped me: https://docs.microsoft.com/en-us/office/vba/api/excel.xlpastetype

It gives a bunch of options to customize how you paste. For instance, you could xlPasteAll (probably what you're looking for), or xlPasteAllUsingSourceTheme, or even xlPasteAllExceptBorders.

Python RuntimeWarning: overflow encountered in long scalars

Here's an example which issues the same warning:

import numpy as np
np.seterr(all='warn')
A = np.array([10])
a=A[-1]
a**a

yields

RuntimeWarning: overflow encountered in long_scalars

In the example above it happens because a is of dtype int32, and the maximim value storable in an int32 is 2**31-1. Since 10**10 > 2**32-1, the exponentiation results in a number that is bigger than that which can be stored in an int32.

Note that you can not rely on np.seterr(all='warn') to catch all overflow errors in numpy. For example, on 32-bit NumPy

>>> np.multiply.reduce(np.arange(21)+1)
-1195114496

while on 64-bit NumPy:

>>> np.multiply.reduce(np.arange(21)+1)
-4249290049419214848

Both fail without any warning, although it is also due to an overflow error. The correct answer is that 21! equals

In [47]: import math

In [48]: math.factorial(21)
Out[50]: 51090942171709440000L

According to numpy developer, Robert Kern,

Unlike true floating point errors (where the hardware FPU sets a flag whenever it does an atomic operation that overflows), we need to implement the integer overflow detection ourselves. We do it on the scalars, but not arrays because it would be too slow to implement for every atomic operation on arrays.

So the burden is on you to choose appropriate dtypes so that no operation overflows.

Do the parentheses after the type name make a difference with new?

Let's get pedantic, because there are differences that can actually affect your code's behavior. Much of the following is taken from comments made to an "Old New Thing" article.

Sometimes the memory returned by the new operator will be initialized, and sometimes it won't depending on whether the type you're newing up is a POD (plain old data), or if it's a class that contains POD members and is using a compiler-generated default constructor.

  • In C++1998 there are 2 types of initialization: zero and default
  • In C++2003 a 3rd type of initialization, value initialization was added.

Assume:

struct A { int m; }; // POD
struct B { ~B(); int m; }; // non-POD, compiler generated default ctor
struct C { C() : m() {}; ~C(); int m; }; // non-POD, default-initialising m

In a C++98 compiler, the following should occur:

  • new A - indeterminate value
  • new A() - zero-initialize

  • new B - default construct (B::m is uninitialized)

  • new B() - default construct (B::m is uninitialized)

  • new C - default construct (C::m is zero-initialized)

  • new C() - default construct (C::m is zero-initialized)

In a C++03 conformant compiler, things should work like so:

  • new A - indeterminate value
  • new A() - value-initialize A, which is zero-initialization since it's a POD.

  • new B - default-initializes (leaves B::m uninitialized)

  • new B() - value-initializes B which zero-initializes all fields since its default ctor is compiler generated as opposed to user-defined.

  • new C - default-initializes C, which calls the default ctor.

  • new C() - value-initializes C, which calls the default ctor.

So in all versions of C++ there's a difference between new A and new A() because A is a POD.

And there's a difference in behavior between C++98 and C++03 for the case new B().

This is one of the dusty corners of C++ that can drive you crazy. When constructing an object, sometimes you want/need the parens, sometimes you absolutely cannot have them, and sometimes it doesn't matter.

Count the number of Occurrences of a Word in a String

Once you find the term you need to remove it from String under process so that it won't resolve the same again, use indexOf() and substring() , you don't need to do contains check length times

What jar should I include to use javax.persistence package in a hibernate based application?

If you are developing an OSGi system I would recommend you to download the "bundlefied" version from Springsource Enterprise Bundle Repository.

Otherwise its ok to use a regular jar-file containing the javax.persistence package

CSS text-overflow: ellipsis; not working?

I faced the same issue and it seems like none of the solution above works for Safari. For non-safari browser, this works just fine:

display: block; /* or in-line block according to your requirement */
overflow: hidden;
white-space: nowrap;
text-overflow: ellipsis;

For Safari, this is the one that works for me. Note that the media query to check if the browser is Safari might change over time, so just tinker with the media query if it doesn't work for you. With line-clamp property, it would also be possible to have multiple lines in the web with ellipsis, see here.

// Media-query for Safari-only browser.
@media not all and (min-resolution: 0.001dpcm) {
  @media {
    -webkit-line-clamp: 1;
    -webkit-box-orient: vertical;
    display: -webkit-box;
    white-space: normal;
  }
}

How to acces external json file objects in vue.js app

Typescript projects (I have typescript in SFC vue components), need to set resolveJsonModule compiler option to true.

In tsconfig.json:

{
  "compilerOptions": {
    ...
    "resolveJsonModule": true,
    ...
  },
  ...
}

Happy coding :)

(Source https://www.typescriptlang.org/docs/handbook/compiler-options.html)

React router nav bar example

Yes, Daniel is correct, but to expand upon his answer, your primary app component would need to have a navbar component within it. That way, when you render the primary app (any page under the '/' path), it would also display the navbar. I am guessing that you wouldn't want your login page to display the navbar, so that shouldn't be a nested component, and should instead be by itself. So your routes would end up looking something like this:

<Router>
  <Route path="/" component={App}>
    <Route path="page1" component={Page1} />
    <Route path="page2" component={Page2} />
  </Route>
  <Route path="/login" component={Login} />
</Router>

And the other components would look something like this:

var NavBar = React.createClass({
  render() {
    return (
      <div>
        <ul>
          <a onClick={() => history.push('page1') }>Page 1</a>
          <a onClick={() => history.push('page2') }>Page 2</a>
        </ul>
      </div>
    )
  }
});

var App = React.createClass({
  render() {
    return (
      <div>
        <NavBar />
        <div>Other Content</div>
        {this.props.children}
      </div>
    )
  }
});

Is there a Wikipedia API?

If you want to extract structured data from Wikipedia, you may consider using DbPedia http://dbpedia.org/

It provides means to query data using given criteria using SPARQL and returns data from parsed Wikipedia infobox templates

Here is a quick example how it could be done in .NET http://www.kozlenko.info/blog/2010/07/20/executing-sparql-query-on-wikipedia-in-net/

There are some SPARQL libraries available for multiple platforms to make queries easier

If Radio Button is selected, perform validation on Checkboxes

function validateDays() {
    if (document.getElementById("option1").checked == true) {
        alert("You have selected Option 1");
    }
    else if (document.getElementById("option2").checked == true) {
        alert("You have selected Option 2");
    }
    else if (document.getElementById("option3").checked == true) {
        alert("You have selected Option 3");
    }
    else {
        // DO NOTHING
        }
    }

How do I copy a range of formula values and paste them to a specific range in another sheet?

You can change

Range("B3:B65536").Copy Destination:=Sheets("DB").Range("B" & lastrow)

to

Range("B3:B65536").Copy 
Sheets("DB").Range("B" & lastrow).PasteSpecial xlPasteValues

BTW, if you have xls file (excel 2003), you would get an error if your lastrow would be greater 3.

Try to use this code instead:

Sub Get_Data()
    Dim lastrowDB As Long, lastrow As Long
    Dim arr1, arr2, i As Integer

    With Sheets("DB")
        lastrowDB = .Cells(.Rows.Count, "A").End(xlUp).Row + 1
    End With

    arr1 = Array("B", "C", "D", "E", "F", "AH", "AI", "AJ", "J", "P", "AF")
    arr2 = Array("B", "A", "C", "P", "D", "E", "G", "F", "H", "I", "J")

    For i = LBound(arr1) To UBound(arr1)
        With Sheets("Sheet1")
             lastrow = Application.Max(3, .Cells(.Rows.Count, arr1(i)).End(xlUp).Row)
             .Range(.Cells(3, arr1(i)), .Cells(lastrow, arr1(i))).Copy
             Sheets("DB").Range(arr2(i) & lastrowDB).PasteSpecial xlPasteValues
        End With
    Next
    Application.CutCopyMode = False
End Sub

Note, above code determines last non empty row on DB sheet in column A (variable lastrowDB). If you need to find lastrow for each destination column in DB sheet, use next modification:

For i = LBound(arr1) To UBound(arr1)
   With Sheets("DB")
       lastrowDB = .Cells(.Rows.Count, arr2(i)).End(xlUp).Row + 1
   End With

   ' NEXT CODE

Next

You could also use next approach instead Copy/PasteSpecial. Replace

.Range(.Cells(3, arr1(i)), .Cells(lastrow, arr1(i))).Copy
Sheets("DB").Range(arr2(i) & lastrowDB).PasteSpecial xlPasteValues

with

Sheets("DB").Range(arr2(i) & lastrowDB).Resize(lastrow - 2).Value = _
      .Range(.Cells(3, arr1(i)), .Cells(lastrow, arr1(i))).Value

Aren't Python strings immutable? Then why does a + " " + b work?

Adding a bit more to above-mentioned answers.

id of a variable changes upon reassignment.

>>> a = 'initial_string'
>>> id(a)
139982120425648
>>> a = 'new_string'
>>> id(a)
139982120425776

Which means that we have mutated the variable a to point to a new string. Now there exist two string(str) objects:

'initial_string' with id = 139982120425648

and

'new_string' with id = 139982120425776

Consider the below code:

>>> b = 'intitial_string'
>>> id(b)
139982120425648

Now, b points to the 'initial_string' and has the same id as a had before reassignment.

Thus, the 'intial_string' has not been mutated.

SQL Order By Count

...none of the other answers seem to do what the asker asked.

For table named 'things' with column 'group':

SELECT
  things.*, counter.count
FROM
  things
LEFT JOIN (
  SELECT
    things.group, count(things.group) as count
  FROM
    things
  GROUP BY
    things.group
) counter ON counter.group = things.group
ORDER BY
  counter.count ASC;

which gives:

id | name  | group | count 
---------------------------
3  | Cat   | B     | 1
1  | Apple | A     | 2
2  | Boy   | A     | 2
4  | Dog   | C     | 3
5  | Elep  | C     | 3
6  | Fish  | C     | 3

How to Set OnClick attribute with value containing function in ie8?

You could also set onclick to call your function like this:

foo.onclick = function() { callYourJSFunction(arg1, arg2); };

This way, you can pass arguments too. .....

Change background position with jQuery

$('#submenu li').hover(function(){
    $('#carousel').css('backgroundPosition', newValue);
});

Angular2 router (@angular/router), how to set default route?

Only you need to add other parameter in your route, the parameter is useAsDefault:true. For example, if you want the DashboardComponent as default you need to do this:

@RouteConfig([
    { path: '/Dashboard', component: DashboardComponent , useAsDefault:true},
    .
    .
    .
    ])

I recomend you to add names to your routes.

{ path: '/Dashboard',name:'Dashboard', component: DashboardComponent , useAsDefault:true}

use video as background for div

Why not fix a <video> and use z-index:-1 to put it behind all other elements?

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

<div style="position: fixed; top: 0; width: 100%; height: 100%; z-index: -1;">
    <video id="video" style="width:100%; height:100%">
        ....
    </video>
</div>
<div class='content'>
    ....

Demo

If you want it within a container you have to add a container element and a little more CSS

/* HTML */
<div class='vidContain'>
    <div class='vid'>
        <video> ... </video>
    </div>
    <div class='content'> ... The rest of your content ... </div>
</div>

/* CSS */
.vidContain {
    width:300px; height:200px;
    position:relative;
    display:inline-block;
    margin:10px;
}
.vid {
    position: absolute; 
    top: 0; left:0;
    width: 100%; height: 100%; 
    z-index: -1;
}    
.content {
    position:absolute;
    top:0; left:0;
    background: black;
    color:white;
}

Demo

A reference to the dll could not be added

  1. start cmd.exe and type:
  2. Regsvr32 %dllpath%
  3. "%dllpath%" replace to your dll path

I can pass a variable from a JSP scriptlet to JSTL but not from JSTL to a JSP scriptlet without an error

@skaffman nailed it down. They live each in its own context. However, I wouldn't consider using scriptlets as the solution. You'd like to avoid them. If all you want is to concatenate strings in EL and you discovered that the + operator fails for strings in EL (which is correct), then just do:

<c:out value="abc${test}" />

Or if abc is to obtained from another scoped variable named ${resp}, then do:

<c:out value="${resp}${test}" />

How to annotate MYSQL autoincrement field with JPA annotations

can you check whether you connected to the correct database. as i was faced same issue, but finally i found that i connected to different database.

identity supports identity columns in DB2, MySQL, MS SQL Server, Sybase and HypersonicSQL. The returned identifier is of type long, short or int.

More Info : http://docs.jboss.org/hibernate/orm/3.5/reference/en/html/mapping.html#mapping-declaration-id

Does delete on a pointer to a subclass call the base class destructor?

class B
{
public:
    B()
    {
       p = new int[1024];  
    }
    virtual ~B()
    {
        cout<<"B destructor"<<endl;
        //p will not be deleted EVER unless you do it manually.
    }
    int *p;
};


class D : public B
{
public:
    virtual ~D()
    {
        cout<<"D destructor"<<endl;
    }
};

When you do:

B *pD = new D();
delete pD;

The destructor will be called only if your base class has the virtual keyword.

Then if you did not have a virtual destructor only ~B() would be called. But since you have a virtual destructor, first ~D() will be called, then ~B().

No members of B or D allocated on the heap will be deallocated unless you explicitly delete them. And deleting them will call their destructor as well.

Spring MVC Missing URI template variable

@PathVariable is used to tell Spring that part of the URI path is a value you want passed to your method. Is this what you want, or are the variables supposed to be form data posted to the URI?

If you want form data, use @RequestParam instead of @PathVariable.

If you want @PathVariable, you need to specify placeholders in the @RequestMapping entry to tell Spring where the path variables fit in the URI. For example, if you want to extract a path variable called contentId, you would use:

@RequestMapping(value = "/whatever/{contentId}", method = RequestMethod.POST)

Edit: Additionally, if your path variable could contain a '.' and you want that part of the data, then you will need to tell Spring to grab everything, not just the stuff before the '.':

@RequestMapping(value = "/whatever/{contentId:.*}", method = RequestMethod.POST)

This is because the default behaviour of Spring is to treat that part of the URL as if it is a file extension, and excludes it from variable extraction.

Find elements inside forms and iframe using Java and Selenium WebDriver

On Selenium >= 3.41 (C#) the rigth syntax is:

webDriver = webDriver.SwitchTo().Frame(webDriver.FindElement(By.Name("icontent")));

How to iterate over columns of pandas dataframe to run regression

You can index dataframe columns by the position using ix.

df1.ix[:,1]

This returns the first column for example. (0 would be the index)

df1.ix[0,]

This returns the first row.

df1.ix[:,1]

This would be the value at the intersection of row 0 and column 1:

df1.ix[0,1]

and so on. So you can enumerate() returns.keys(): and use the number to index the dataframe.

How to style a clicked button in CSS

Unfortunately, there is no :click pseudo selector. If you want to change styling on click, you should use Jquery/Javascript. It certainly is better than the "hack" for pure HTML / CSS. But if you insist...

_x000D_
_x000D_
input {_x000D_
display: none;_x000D_
}_x000D_
span {_x000D_
padding: 20px;_x000D_
font-family: sans-serif;_x000D_
}_x000D_
input:checked + span {_x000D_
  background: #444;_x000D_
  color: #fff;_x000D_
}
_x000D_
  <label for="input">_x000D_
  <input id="input" type="radio" />_x000D_
  <span>NO JS styling</span>_x000D_
  </label>
_x000D_
_x000D_
_x000D_

Or, if you prefer, you can toggle the styling:

_x000D_
_x000D_
input {_x000D_
display: none;_x000D_
}_x000D_
span {_x000D_
padding: 20px;_x000D_
font-family: sans-serif;_x000D_
}_x000D_
input:checked + span {_x000D_
  background: #444;_x000D_
  color: #fff;_x000D_
}
_x000D_
  <label for="input">_x000D_
  <input id="input" type="checkbox" />_x000D_
  <span>NO JS styling</span>_x000D_
  </label>
_x000D_
_x000D_
_x000D_

Applying CSS styles to all elements inside a DIV

#applyCSS > * {
  /* Your style */
}

Check this JSfiddle

It will style all children and grandchildren, but will exclude loosely flying text in the div itself and only target wrapped (by tags) content.

How to compile and run C/C++ in a Unix console/Mac terminal?

All application execution in a Unix (Linux, Mac OS X, AIX, etc.) environment depends on the executable search path.

You can display this path in the terminal with this command:

echo $PATH

On Mac OS X (by default) this will display the following colon separated search path:

/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin

So any executable in the listed directories can by run just by typing in their name. For example:

cat mytextfile.txt

This runs /bin/cat and displays mytextfile.txt to the terminal.

To run any other command that is not in the executable search path requires that you qualify the path to the executable. So say I had an executable called MyProgram in my home directory on Mac OS X I can fully qualify it like so:

/Users/oliver/MyProgram

If you are in a location that is near the program you wished to execute you can qualify the name with a partial path. For example, if MyProgram was in the directory /Users/oliver/MyProject I and I was in my home directory I can qualify the executable name like this, and have it execute:

MyProject/MyProgram

Or say I was in the directory /Users/oliver/MyProject2 and I wanted to execute /Users/oliver/MyProject/MyProgram I can use a relative path like this, to execute it:

../MyProject/MyProgram

Similarly if I am in the same directory as MyProgram I need to use a "current directory" relative path. The current directory you are in is the period character followed by a slash. For example:

./MyProgram

To determine which directory you are currently in use the pwd command.

If you are commonly putting programs in a place on your hard disk that you wish to run without having to qualify their names. For example, if you have a "bin" directory in your home directory for regularly used shell scripts of other programs it may be wise to alter your executable search path.

This can be does easily by either creating or editing the existing .bash_profile file in your home directory and adding the lines:

#!/bin/sh
export PATH=$PATH:~/bin

Here the tilde (~) character is being used as a shortcut for /Users/oliver. Also note that the hash bang (#!) line needs to be the first line of the file (if it doesn't already exist). Note also that this technique requires that your login shell be bash (the default on Mac OS X and most Linux distributions). Also note that if you want your programs installed in ~/bin to be used in preference to system executables your should reorder the export statement as follows:

export PATH=~/bin:$PATH

How to return JSon object

First of all, there's no such thing as a JSON object. What you've got in your question is a JavaScript object literal (see here for a great discussion on the difference). Here's how you would go about serializing what you've got to JSON though:

I would use an anonymous type filled with your results type:

string json = JsonConvert.SerializeObject(new
{
    results = new List<Result>()
    {
        new Result { id = 1, value = "ABC", info = "ABC" },
        new Result { id = 2, value = "JKL", info = "JKL" }
    }
});

Also, note that the generated JSON has result items with ids of type Number instead of strings. I doubt this will be a problem, but it would be easy enough to change the type of id to string in the C#.

I'd also tweak your results type and get rid of the backing fields:

public class Result
{
    public int id { get ;set; }
    public string value { get; set; }
    public string info { get; set; }
}

Furthermore, classes conventionally are PascalCased and not camelCased.

Here's the generated JSON from the code above:

{
  "results": [
    {
      "id": 1,
      "value": "ABC",
      "info": "ABC"
    },
    {
      "id": 2,
      "value": "JKL",
      "info": "JKL"
    }
  ]
}

Using LIKE operator with stored procedure parameters

Your datatype for @location nchar(20) should be @location nvarchar(20), since nChar has a fixed length (filled with Spaces).
If Location is nchar too you will have to convert it:

 ... Cast(Location as nVarchar(200)) like '%'+@location+'%' ...   

To enable nullable parameters with and AND condition just use IsNull or Coalesce for comparison, which is not needed in your example using OR.

e.g. if you would like to compare for Location AND Date and Time.

@location nchar(20),
@time time,
@date date
as
select DonationsTruck.VechileId, Phone, Location, [Date], [Time]
from Vechile, DonationsTruck
where Vechile.VechileId = DonationsTruck.VechileId
and (((Location like '%'+IsNull(@location,Location)+'%')) and [Date]=IsNUll(@date,date) and [Time] = IsNull(@time,Time))

Any way to declare an array in-line?

Other option is to use ArrayUtils.toArray in org.apache.commons.lang3

ArrayUtils.toArray("elem1","elem2")

About the Full Screen And No Titlebar from manifest

To set your App or any individual activity display in Full Screen mode, insert the code

<application 
    android:icon="@drawable/icon" 
    android:label="@string/app_name" 
    android:theme="@android:style/Theme.NoTitleBar.Fullscreen">

in AndroidManifest.xml, under application or activity tab.

How to deploy a war file in Tomcat 7

This has been working for me:

  1. Create your war file (mysite.war) locally.
  2. Rename it locally to something besides .war, like mysite.www
  3. With tomcat still running, upload mysite.www to webapps directory.
  4. After it finishes uploading, delete the previous version mysite.war
  5. List the directory, watching for the directory /mysite to disappear.
  6. Rename mysite.www to be mysite.war
  7. List the directory, watching for the new /mysite to be created.

If you try uploading the new file as a war file, with tomcat still running, it will attempt to expand it before it is all there. It will fail. Having failed, it will not try again. Thus, uploading a www file, then renaming it, allows the whole war file to be present before tomcat notices it.

Hint, don't forget to check that the war file's owner is tomcat (Use chown)

PDO Prepared Inserts multiple rows in single query

For what it is worth, I have seen a lot of users recommend iterating through INSERT statements instead of building out as a single string query as the selected answer did. I decided to run a simple test with just two fields and a very basic insert statement:

<?php
require('conn.php');

$fname = 'J';
$lname = 'M';

$time_start = microtime(true);
$stmt = $db->prepare('INSERT INTO table (FirstName, LastName) VALUES (:fname, :lname)');

for($i = 1; $i <= 10; $i++ )  {
    $stmt->bindParam(':fname', $fname);
    $stmt->bindParam(':lname', $lname);
    $stmt->execute();

    $fname .= 'O';
    $lname .= 'A';
}


$time_end = microtime(true);
$time = $time_end - $time_start;

echo "Completed in ". $time ." seconds <hr>";

$fname2 = 'J';
$lname2 = 'M';

$time_start2 = microtime(true);
$qry = 'INSERT INTO table (FirstName, LastName) VALUES ';
$qry .= "(?,?), ";
$qry .= "(?,?), ";
$qry .= "(?,?), ";
$qry .= "(?,?), ";
$qry .= "(?,?), ";
$qry .= "(?,?), ";
$qry .= "(?,?), ";
$qry .= "(?,?), ";
$qry .= "(?,?), ";
$qry .= "(?,?)";

$stmt2 = $db->prepare($qry);
$values = array();

for($j = 1; $j<=10; $j++) {
    $values2 = array($fname2, $lname2);
    $values = array_merge($values,$values2);

    $fname2 .= 'O';
    $lname2 .= 'A';
}

$stmt2->execute($values);

$time_end2 = microtime(true);
$time2 = $time_end2 - $time_start2;

echo "Completed in ". $time2 ." seconds <hr>";
?>

While the overall query itself took milliseconds or less, the latter (single string) query was consistently 8 times faster or more. If this was built out to say reflect an import of thousands of rows on many more columns, the difference could be enormous.

Returning http 200 OK with error within response body

No, this is very incorrect.

HTTP is an application protocol. 200 implies that the response contains a payload that represents the status of the requested resource. An error message usually is not a representation of that resource.

If something goes wrong while processing GET, the right status code is 4xx ("you messed up") or 5xx ("I messed up").

How to empty a char array?

Don't bother trying to zero-out your char array if you are dealing with strings. Below is a simple way to work with the char strings.

Copy (assign new string):

strcpy(members, "hello");

Concatenate (add the string):

strcat(members, " world");

Empty string:

members[0] = 0;

Simple like that.

'MOD' is not a recognized built-in function name

If using JDBC driver you may use function escape sequence like this:

select {fn MOD(5, 2)}
#Result 1

select  mod(5, 2)
#SQL Error [195] [S00010]: 'mod' is not a recognized built-in function name.

GROUP BY and COUNT in PostgreSQL

There is also EXISTS:

SELECT count(*) AS post_ct
FROM   posts p
WHERE  EXISTS (SELECT FROM votes v WHERE v.post_id = p.id);

In Postgres and with multiple entries on the n-side like you probably have, it's generally faster than count(DISTINCT post_id):

SELECT count(DISTINCT p.id) AS post_ct
FROM   posts p
JOIN   votes v ON v.post_id = p.id;

The more rows per post there are in votes, the bigger the difference in performance. Test with EXPLAIN ANALYZE.

count(DISTINCT post_id) has to read all rows, sort or hash them, and then only consider the first per identical set. EXISTS will only scan votes (or, preferably, an index on post_id) until the first match is found.

If every post_id in votes is guaranteed to be present in the table posts (referential integrity enforced with a foreign key constraint), this short form is equivalent to the longer form:

SELECT count(DISTINCT post_id) AS post_ct
FROM   votes;

May actually be faster than the EXISTS query with no or few entries per post.

The query you had works in simpler form, too:

SELECT count(*) AS post_ct
FROM  (
    SELECT FROM posts 
    JOIN   votes ON votes.post_id = posts.id 
    GROUP  BY posts.id
    ) sub;

Benchmark

To verify my claims I ran a benchmark on my test server with limited resources. All in a separate schema:

Test setup

Fake a typical post / vote situation:

CREATE SCHEMA y;
SET search_path = y;

CREATE TABLE posts (
  id   int PRIMARY KEY
, post text
);

INSERT INTO posts
SELECT g, repeat(chr(g%100 + 32), (random()* 500)::int)  -- random text
FROM   generate_series(1,10000) g;

DELETE FROM posts WHERE random() > 0.9;  -- create ~ 10 % dead tuples

CREATE TABLE votes (
  vote_id serial PRIMARY KEY
, post_id int REFERENCES posts(id)
, up_down bool
);

INSERT INTO votes (post_id, up_down)
SELECT g.* 
FROM  (
   SELECT ((random()* 21)^3)::int + 1111 AS post_id  -- uneven distribution
        , random()::int::bool AS up_down
   FROM   generate_series(1,70000)
   ) g
JOIN   posts p ON p.id = g.post_id;

All of the following queries returned the same result (8093 of 9107 posts had votes).
I ran 4 tests with EXPLAIN ANALYZE ant took the best of five on Postgres 9.1.4 with each of the three queries and appended the resulting total runtimes.

  1. As is.

  2. After ..

    ANALYZE posts;
    ANALYZE votes;
    
  3. After ..

    CREATE INDEX foo on votes(post_id);
    
  4. After ..

    VACUUM FULL ANALYZE posts;
    CLUSTER votes using foo;
    

count(*) ... WHERE EXISTS

  1. 253 ms
  2. 220 ms
  3. 85 ms -- winner (seq scan on posts, index scan on votes, nested loop)
  4. 85 ms

count(DISTINCT x) - long form with join

  1. 354 ms
  2. 358 ms
  3. 373 ms -- (index scan on posts, index scan on votes, merge join)
  4. 330 ms

count(DISTINCT x) - short form without join

  1. 164 ms
  2. 164 ms
  3. 164 ms -- (always seq scan)
  4. 142 ms

Best time for original query in question:

  • 353 ms

For simplified version:

  • 348 ms

@wildplasser's query with a CTE uses the same plan as the long form (index scan on posts, index scan on votes, merge join) plus a little overhead for the CTE. Best time:

  • 366 ms

Index-only scans in the upcoming PostgreSQL 9.2 can improve the result for each of these queries, most of all for EXISTS.

Related, more detailed benchmark for Postgres 9.5 (actually retrieving distinct rows, not just counting):

How to keep console window open

If you want to keep it open when you are debugging, but still let it close normally when not debugging, you can do something like this:

if (System.Diagnostics.Debugger.IsAttached) Console.ReadLine();

Like other answers have stated, the call to Console.ReadLine() will keep the window open until enter is pressed, but Console.ReadLine() will only be called if the debugger is attached.

Java best way for string find and replace?

you can use pattern matcher as well, which will replace all in one shot.

Pattern keyPattern = Pattern.compile(key); Matcher matcher = keyPattern.matcher(str); String nerSrting = matcher.replaceAll(value);

Create a map with clickable provinces/states using SVG, HTML/CSS, ImageMap

I have been using makeaclickablemap for my province maps for some time now and it turned out to be a really good fit.

VBScript -- Using error handling

VBScript has no notion of throwing or catching exceptions, but the runtime provides a global Err object that contains the results of the last operation performed. You have to explicitly check whether the Err.Number property is non-zero after each operation.

On Error Resume Next

DoStep1

If Err.Number <> 0 Then
  WScript.Echo "Error in DoStep1: " & Err.Description
  Err.Clear
End If

DoStep2

If Err.Number <> 0 Then
  WScript.Echo "Error in DoStop2:" & Err.Description
  Err.Clear
End If

'If you no longer want to continue following an error after that block's completed,
'call this.
On Error Goto 0

The "On Error Goto [label]" syntax is supported by Visual Basic and Visual Basic for Applications (VBA), but VBScript doesn't support this language feature so you have to use On Error Resume Next as described above.

How to select records without duplicate on just one field in SQL?

Duplicate rows can be removed for Complex Queries by,

First storing the result to a #TempTable or @TempTableVariable

Delete from #TempTable or @TempTableVariable where your condition

Then select the rest of the data.

If need to create a row number create an identity column.

Convert .pem to .crt and .key

This is what I did on windows.

  1. Download a zip file that contains the open ssl exe from Google
  2. Unpack the zip file and go into the bin folder.
  3. Go to the address bar in the bin folder and type cmd. This will open a command prompt at this folder.
  4. move/Put the .pem file into this bin folder.
  5. Run two commands. One creates the cert and the second the key file
openssl x509 -outform der -in yourPemFilename.pem -out certfileOutName.crt
openssl rsa -in yourPemFilename.pem -out keyfileOutName.key

How to use Bootstrap 4 in ASP.NET Core

What does the trick for me is:

1) Right click on wwwroot > Add > Client Side Library

2) Typed "bootstrap" on the search box

3) Select "Choose specific files"

4) Scroll down and select a folder. In my case I chose "twitter-bootstrap"

5) Check "css" and "js"

6) Click "Install".

A few seconds later I have all of them wwwroot folder. Do the same for all client side packages that you want to add.

How to increase Java heap space for a tomcat app

For Windows Service, you need to run tomcat9w.exe (or 6w/7w/8w) depending on your version of tomcat. First, make sure tomcat is stopped. Then double click on tomcat9w.exe. Navigate to the Java tab. If you know you have 64 bit Windows with 64 bit Java and 64 bit Tomcat, then feel free to set the memory higher than 512. You'll need to do some task manager monitoring to determine how high to set it. For most apps developed in 2019... I'd recommend an initial memory pool of 1024, and the maximum memory pool of 2048. Of course if your computer has tons of RAM... feel free to go as high as you want. Also, see this answer: How to increase Maximum Memory Pool Size? Apache Tomcat 9

nvm keeps "forgetting" node in new terminal session

Try nvm alias default. For example:

$ nvm alias default 0.12.7

This sets the default node version in your shell. Then verify that the change persists by closing the shell window, opening a new one, then: node --version

The database cannot be opened because it is version 782. This server supports version 706 and earlier. A downgrade path is not supported

Try to change the compatibility level, worked for me.

Verify what level it is

USE VJ_DATABASE;
GO
SELECT compatibility_level
FROM sys.databases WHERE name = 'VJ_DATABASE';
GO

Then make it compatible with the older version

ALTER DATABASE VJ_DATABASE
SET COMPATIBILITY_LEVEL = 110;   
GO
  • 100 = Sql Server 2008
  • 110 = Sql Server 2012
  • 120 = Sql Server 2014

By default, Sql Server 2014 will change the db versions compatibility to only 2014, using the @@ version you should be able to tell, which version Sql Server is.

Then run the command above to change it the version you have.

Additional step: Ensure you look at the accessibility of the DB is not reset, do this by right clicking on properties of the folder and the database. (make sure you have rights so you don't get an access denied)

HTML / CSS table with GRIDLINES

Via css. Put this inside the <head> tag.

<style type="text/css" media="screen">

table{
border-collapse:collapse;
border:1px solid #FF0000;
}

table td{
border:1px solid #FF0000;
}
</style>

What is the default initialization of an array in Java?

Everything in a Java program not explicitly set to something by the programmer, is initialized to a zero value.

  • For references (anything that holds an object) that is null.
  • For int/short/byte/long that is a 0.
  • For float/double that is a 0.0
  • For booleans that is a false.
  • For char that is the null character '\u0000' (whose decimal equivalent is 0).

When you create an array of something, all entries are also zeroed. So your array contains five zeros right after it is created by new.

Note (based on comments): The Java Virtual Machine is not required to zero out the underlying memory when allocating local variables (this allows efficient stack operations if needed) so to avoid random values the Java Language Specification requires local variables to be initialized.

Python regex findall

you can replace your pattern with

regex = ur"\[P\]([\w\s]+)\[\/P\]"

Horizontal list items

This fiddle shows how

http://jsfiddle.net/9th7X/

ul, li {
    display:inline
}

Great references on lists and css here:

http://alistapart.com/article/taminglists/

Accept server's self-signed ssl certificate in Java client

Trust all SSL certificates:- You can bypass SSL if you want to test on the testing server. But do not use this code for production.

public static class NukeSSLCerts {
protected static final String TAG = "NukeSSLCerts";

public static void nuke() {
    try {
        TrustManager[] trustAllCerts = new TrustManager[] { 
            new X509TrustManager() {
                public X509Certificate[] getAcceptedIssuers() {
                    X509Certificate[] myTrustedAnchors = new X509Certificate[0];  
                    return myTrustedAnchors;
                }

                @Override
                public void checkClientTrusted(X509Certificate[] certs, String authType) {}

                @Override
                public void checkServerTrusted(X509Certificate[] certs, String authType) {}
            }
        };

        SSLContext sc = SSLContext.getInstance("SSL");
        sc.init(null, trustAllCerts, new SecureRandom());
        HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
        HttpsURLConnection.setDefaultHostnameVerifier(new HostnameVerifier() {
            @Override
            public boolean verify(String arg0, SSLSession arg1) {
                return true;
            }
        });
    } catch (Exception e) { 
    }
}

}

Please call this function in onCreate() function in Activity or in your Application Class.

NukeSSLCerts.nuke();

This can be used for Volley in Android.

How does String substring work in Swift

I'm really frustrated at Swift's String access model: everything has to be an Index. All I want is to access the i-th character of the string using Int, not the clumsy index and advancing (which happens to change with every major release). So I made an extension to String:

extension String {
    func index(from: Int) -> Index {
        return self.index(startIndex, offsetBy: from)
    }

    func substring(from: Int) -> String {
        let fromIndex = index(from: from)
        return String(self[fromIndex...])
    }

    func substring(to: Int) -> String {
        let toIndex = index(from: to)
        return String(self[..<toIndex])
    }

    func substring(with r: Range<Int>) -> String {
        let startIndex = index(from: r.lowerBound)
        let endIndex = index(from: r.upperBound)
        return String(self[startIndex..<endIndex])
    }
}

let str = "Hello, playground"
print(str.substring(from: 7))         // playground
print(str.substring(to: 5))           // Hello
print(str.substring(with: 7..<11))    // play

How to remove docker completely from ubuntu 14.04

@miyuru. As suggested by him run all the steps.

Ubuntu version 16.04

Still when I ran docker --version it was returning a version. So to uninstall it completely

Again run the dpkg -l | grep -i docker which will list package still there in system.

For example:

ii  docker-ce-cli      5:19.03.6~3-0~ubuntu-xenial               
amd64        Docker CLI: the open-source application container engine

Now remove them as show below :

sudo apt-get purge -y docker-ce-cli

sudo apt-get autoremove -y --purge docker-ce-cli

sudo apt-get autoclean

Hope this will resolve it, as it did in my case.

lists and arrays in VBA

You will have to change some of your data types but the basics of what you just posted could be converted to something similar to this given the data types I used may not be accurate.

Dim DateToday As String: DateToday = Format(Date, "yyyy/MM/dd")
Dim Computers As New Collection
Dim disabledList As New Collection
Dim compArray(1 To 1) As String

'Assign data to first item in array
compArray(1) = "asdf"

'Format = Item, Key
Computers.Add "ErrorState", "Computer Name"

'Prints "ErrorState"
Debug.Print Computers("Computer Name")

Collections cannot be sorted so if you need to sort data you will probably want to use an array.

Here is a link to the outlook developer reference. http://msdn.microsoft.com/en-us/library/office/ff866465%28v=office.14%29.aspx

Another great site to help you get started is http://www.cpearson.com/Excel/Topic.aspx

Moving everything over to VBA from VB.Net is not going to be simple since not all the data types are the same and you do not have the .Net framework. If you get stuck just post the code you're stuck converting and you will surely get some help!

Edit:

Sub ArrayExample()
    Dim subject As String
    Dim TestArray() As String
    Dim counter As Long

    subject = "Example"
    counter = Len(subject)

    ReDim TestArray(1 To counter) As String

    For counter = 1 To Len(subject)
        TestArray(counter) = Right(Left(subject, counter), 1)
    Next
End Sub

SQL Views - no variables?

What I do is create a view that performs the same select as the table variable and link that view into the second view. So a view can select from another view. This achieves the same result

Validate phone number with JavaScript

Validate phone number + return formatted data

_x000D_
_x000D_
function validTel(str){_x000D_
  str = str.replace(/[^0-9]/g, '');_x000D_
  var l = str.length;_x000D_
  if(l<10) return ['error', 'Tel number length < 10'];_x000D_
  _x000D_
  var tel = '', num = str.substr(-7),_x000D_
      code = str.substr(-10, 3),_x000D_
      coCode = '';_x000D_
  if(l>10) {_x000D_
    coCode = '+' + str.substr(0, (l-10) );_x000D_
  }_x000D_
  tel = coCode +' ('+ code +') '+ num;_x000D_
  _x000D_
  return ['succes', tel];_x000D_
}_x000D_
_x000D_
console.log(validTel('+1 [223] 123.45.67'));
_x000D_
_x000D_
_x000D_

What regular expression will match valid international phone numbers?

It works pretty well with 00xx and +xx:

^(?:00|\+)(9[976]\d|8[987530]\d|6[987]\d|5[90]\d|42\d|3[875]\d|2[98654321]\d|9[8543210]|8[6421]|6[6543210]|5[87654321]|4[987654310]|3[9643210]|2[70]|7|1)\d{1,14}$

Find Number of CPUs and Cores per CPU using Command Prompt

If you want to find how many processors (or CPUs) a machine has the same way %NUMBER_OF_PROCESSORS% shows you the number of cores, save the following script in a batch file, for example, GetNumberOfCores.cmd:

@echo off
for /f "tokens=*" %%f in ('wmic cpu get NumberOfCores /value ^| find "="') do set %%f

And then execute like this:

GetNumberOfCores.cmd

echo %NumberOfCores%

The script will set a environment variable named %NumberOfCores% and it will contain the number of processors.

SQL Server : converting varchar to INT

You could try updating the table to get rid of these characters:

UPDATE dbo.[audit]
  SET UserID = REPLACE(UserID, CHAR(0), '')
  WHERE CHARINDEX(CHAR(0), UserID) > 0;

But then you'll also need to fix whatever is putting this bad data into the table in the first place. In the meantime perhaps try:

SELECT CONVERT(INT, REPLACE(UserID, CHAR(0), ''))
  FROM dbo.[audit];

But that is not a long term solution. Fix the data (and the data type while you're at it). If you can't fix the data type immediately, then you can quickly find the culprit by adding a check constraint:

ALTER TABLE dbo.[audit]
  ADD CONSTRAINT do_not_allow_stupid_data
  CHECK (CHARINDEX(CHAR(0), UserID) = 0);

EDIT

Ok, so that is definitely a 4-digit integer followed by six instances of CHAR(0). And the workaround I posted definitely works for me:

DECLARE @foo TABLE(UserID VARCHAR(32));
INSERT @foo SELECT 0x31353831000000000000;

-- this succeeds:
SELECT CONVERT(INT, REPLACE(UserID, CHAR(0), '')) FROM @foo;

-- this fails:
SELECT CONVERT(INT, UserID) FROM @foo;

Please confirm that this code on its own (well, the first SELECT, anyway) works for you. If it does then the error you are getting is from a different non-numeric character in a different row (and if it doesn't then perhaps you have a build where a particular bug hasn't been fixed). To try and narrow it down you can take random values from the following query and then loop through the characters:

SELECT UserID, CONVERT(VARBINARY(32), UserID)
  FROM dbo.[audit]
  WHERE UserID LIKE '%[^0-9]%';

So take a random row, and then paste the output into a query like this:

DECLARE @x VARCHAR(32), @i INT;
SET @x = CONVERT(VARCHAR(32), 0x...); -- paste the value here
SET @i = 1;
WHILE @i <= LEN(@x)
BEGIN
  PRINT RTRIM(@i) + ' = ' + RTRIM(ASCII(SUBSTRING(@x, @i, 1)))
  SET @i = @i + 1;
END

This may take some trial and error before you encounter a row that fails for some other reason than CHAR(0) - since you can't really filter out the rows that contain CHAR(0) because they could contain CHAR(0) and CHAR(something else). For all we know you have values in the table like:

SELECT '15' + CHAR(9) + '23' + CHAR(0);

...which also can't be converted to an integer, whether you've replaced CHAR(0) or not.

I know you don't want to hear it, but I am really glad this is painful for people, because now they have more war stories to push back when people make very poor decisions about data types.

Windows- Pyinstaller Error "failed to execute script " When App Clicked

I got the same error and figured out that i wrote my script using Anaconda but pyinstaller tries to pack script on pure python. So, modules not exist in pythons library folder cause this problem.

How to create id with AUTO_INCREMENT on Oracle?

FUNCTION UNIQUE2(
 seq IN NUMBER
) RETURN VARCHAR2
AS
 i NUMBER := seq;
 s VARCHAR2(9);
 r NUMBER(2,0);
BEGIN
  WHILE i > 0 LOOP
    r := MOD( i, 36 );
    i := ( i - r ) / 36;
    IF ( r < 10 ) THEN
      s := TO_CHAR(r) || s;
    ELSE
      s := CHR( 55 + r ) || s;
    END IF;
  END LOOP;
  RETURN 'ID'||LPAD( s, 14, '0' );
END;

Difference between View and table in sql

A table contains data, a view is just a SELECT statement which has been saved in the database (more or less, depending on your database).

The advantage of a view is that it can join data from several tables thus creating a new view of it. Say you have a database with salaries and you need to do some complex statistical queries on it.

Instead of sending the complex query to the database all the time, you can save the query as a view and then SELECT * FROM view

How to find the files that are created in the last hour in unix

Check out this link for more details.

To find files which are created in last one hour in current directory, you can use -amin

find . -amin -60 -type f

This will find files which are created with in last 1 hour.

Can I apply the required attribute to <select> fields in HTML5?

Try this

<select>
<option value="" style="display:none">Please select</option>
<option value="one">One</option>
</select>

Plot a horizontal line using matplotlib

In addition to the most upvoted answer here, one can also chain axhline after calling plot on a pandas's DataFrame.

import pandas as pd

(pd.DataFrame([1, 2, 3])
   .plot(kind='bar', color='orange')
   .axhline(y=1.5));

enter image description here

Load a Bootstrap popover content with AJAX. Is this possible?

This works for me, this code fix possibles alignment issues:

<a class="ajax-popover" data-container="body" data-content="Loading..." data-html="data-html" data-placement="bottom" data-title="Title" data-toggle="popover" data-trigger="focus" data-url="your_url" role="button" tabindex="0" data-original-title="" title="">
  <i class="fa fa-info-circle"></i>
</a>

$('.ajax-popover').click(function() {
  var e = $(this);
  if (e.data('loaded') !== true) {
    $.ajax({
      url: e.data('url'),
      dataType: 'html',
      success: function(data) {
        e.data('loaded', true);
        e.attr('data-content', data);
        var popover = e.data('bs.popover');
        popover.setContent();
        popover.$tip.addClass(popover.options.placement);
        var calculated_offset = popover.getCalculatedOffset(popover.options.placement, popover.getPosition(), popover.$tip[0].offsetWidth, popover.$tip[0].offsetHeight);
        popover.applyPlacement(calculated_offset, popover.options.placement);
      },
      error: function(jqXHR, textStatus, errorThrown) {
        return instance.content('Failed to load data');
      }
    });
  }
});

Just in case, the endpoint I'm using returns html (a rails partial)

I took some part of the code from here https://stackoverflow.com/a/13565154/3984542

Lazy Method for Reading Big File in Python?

f = ... # file-like object, i.e. supporting read(size) function and 
        # returning empty string '' when there is nothing to read

def chunked(file, chunk_size):
    return iter(lambda: file.read(chunk_size), '')

for data in chunked(f, 65536):
    # process the data

UPDATE: The approach is best explained in https://stackoverflow.com/a/4566523/38592

Checking if a list is empty with LINQ

I would make one small addition to the code you seem to have settled on: check also for ICollection, as this is implemented even by some non-obsolete generic classes as well (i.e., Queue<T> and Stack<T>). I would also use as instead of is as it's more idiomatic and has been shown to be faster.

public static bool IsEmpty<T>(this IEnumerable<T> list)
{
    if (list == null)
    {
        throw new ArgumentNullException("list");
    }

    var genericCollection = list as ICollection<T>;
    if (genericCollection != null)
    {
        return genericCollection.Count == 0;
    }

    var nonGenericCollection = list as ICollection;
    if (nonGenericCollection != null)
    {
        return nonGenericCollection.Count == 0;
    }

    return !list.Any();
}

How do I fix 'Invalid character value for cast specification' on a date column in flat file?

In order to simulate the issue that you are facing, I created the following sample using SSIS 2008 R2 with SQL Server 2008 R2 backend. The example is based on what I gathered from your question. This example doesn't provide a solution but it might help you to identify where the problem could be in your case.

Created a simple CSV file with two columns namely order number and order date. As you had mentioned in your question, values of both the columns are qualified with double quotes (") and also the lines end with Line Feed (\n) with the date being the last column. The below screenshot was taken using Notepad++, which can display the special characters in a file. LF in the screenshot denotes Line Feed.

Orders file

Created a simple table named dbo.Destination in the SQL Server database to populate the CSV file data using SSIS package. Create script for the table is given below.

CREATE TABLE [dbo].[Destination](
    [OrderNumber] [varchar](50) NULL,
    [OrderDate] [date] NULL
) ON [PRIMARY]
GO

On the SSIS package, I created two connection managers. SQLServer was created using the OLE DB Connection to connect to the SQL Server database. FlatFile is a flat file connection manager.

Connections

Flat file connection manager was configured to read the CSV file and the settings are shown below. The red arrows indicate the changes made.

Provided a name to the flat file connection manager. Browsed to the location of the CSV file and selected the file path. Entered the double quote (") as the text qualifier. Changed the Header row delimiter from {CR}{LF} to {LF}. This header row delimiter change also reflects on the Columns section.

Flat File General

No changes were made in the Columns section.

Flat File Columns

Changed the column name from Column0 to OrderNumber.

Advanced column OrderNumber

Changed the column name from Column1 to OrderDate and also changed the data type to date [DT_DATE]

Advanced column OrderDate

Preview of the data within the flat file connection manager looks good.

Data Preview

On the Control Flow tab of the SSIS package, placed a Data Flow Task.

Control Flow

Within the Data Flow Task, placed a Flat File Source and an OLE DB Destination.

Data Flow Task

The Flat File Source was configured to read the CSV file data using the FlatFile connection manager. Below three screenshots show how the flat file source component was configured.

Flat File Source Connection Manager

Flat File Source Columns

Flat File Source Error Output

The OLE DB Destination component was configured to accept the data from Flat File Source and insert it into SQL Server database table named dbo.Destination. Below three screenshots show how the OLE DB Destination component was configured.

OLE DB Destination Connection Manager

OLE DB Destination Mappings

OLE DB Destination Error Output

Using the steps mentioned in the below 5 screenshots, I added a data viewer on the flow between the Flat File Source and OLE DB Destination.

Right click

Data Flow Path Editor New

Configure Data Viewer

Data Flow Path Editor Added

Data Viewer visible

Before running the package, I verified the initial data present in the table. It is currently empty because I created this using the script provided at the beginning of this post.

Empty Table

Executed the package and the package execution temporarily paused to display the data flowing from Flat File Source to OLE DB Destination in the data viewer. I clicked on the run button to proceed with the execution.

Data Viewer Pause

The package executed successfully.

Successful execution

Flat file source data was inserted successfully into the table dbo.Destination.

Data in table

Here is the layout of the table dbo.Destination. As you can see, the field OrderDate is of data type date and the package still continued to insert the data correctly.

Destination layout

This post even though is not a solution. Hopefully helps you to find out where the problem could be in your scenario.

JavaScript style.display="none" or jQuery .hide() is more efficient?

a = 2;

vs

a(2);
function a(nb) {
    lot;
    of = cross;
    browser();
    return handling(nb);
}

In your opinion, what do you think is going to be the fastest?

VBA: Conditional - Is Nothing

Based on your comment to Issun:

Thanks for the explanation. In my case, The object is declared and created prior to the If condition. So, How do I use If condition to check for < No Variables> ? In other words, I do not want to execute My_Object.Compute if My_Object has < No Variables>

You need to check one of the properties of the object. Without telling us what the object is, we cannot help you.

I did test several common objects and found that an instantiated Collection with no items added shows <No Variables> in the watch window. If your object is indeed a collection, you can check for the <No Variables> condition using the .Count property:

Sub TestObj()
Dim Obj As Object
    Set Obj = New Collection
    If Obj Is Nothing Then
        Debug.Print "Object not instantiated"
    Else
        If Obj.Count = 0 Then
            Debug.Print "<No Variables> (ie, no items added to the collection)"
        Else
            Debug.Print "Object instantiated and at least one item added"
        End If
    End If
End Sub

It is also worth noting that if you declare any object As New then the Is Nothing check becomes useless. The reason is that when you declare an object As New then it gets created automatically when it is first called, even if the first time you call it is to see if it exists!

Dim MyObject As New Collection
If MyObject Is Nothing Then  ' <--- This check always returns False

This does not seem to be the cause of your specific problem. But, since others may find this question through a Google search, I wanted to include it because it is a common beginner mistake.

Android: How can I print a variable on eclipse console?

Ok, Toast is no complex but it need a context object to work, it could be MyActivity.this, then you can write:

Toast.maketext(MyActivity.this, "Toast text to show", Toast.LENGTH_SHORT).show();

Although Toast is a UI resource, then using it in another thread different to ui thread, will send an error or simply not work If you want to print a variable, put the variable name.toString() and concat that with text you want in the maketext String parameter ;)

How to load data from a text file in a PostgreSQL database?

Let consider that your data are in the file values.txt and that you want to import them in the database table myTable then the following query does the job

COPY myTable FROM 'value.txt' (DELIMITER('|'));

https://www.postgresql.org/docs/current/static/sql-copy.html

jQuery: what is the best way to restrict "number"-only input for textboxes? (allow decimal points)

i use that function and it works fine

$(document).ready(function () {
        $("#txt_Price").keypress(function (e) {
            //if the letter is not digit then display error and don't type anything
            //if (e.which != 8 && e.which != 0 && (e.which < 48 || e.which > 57)) 
            if ((e.which != 46 || $(this).val().indexOf('.') != -1) && (e.which < 48 || e.which > 57)) {
                //display error message
                $("#errmsg").html("Digits Only").show().fadeOut("slow");
                return false;
            }
        });
    }); 

Check if multiple strings exist in another string

flog = open('test.txt', 'r')
flogLines = flog.readlines()
strlist = ['SUCCESS', 'Done','SUCCESSFUL']
res = False
for line in flogLines:
     for fstr in strlist:
         if line.find(fstr) != -1:
            print('found') 
            res = True


if res:
    print('res true')
else: 
    print('res false')

output example image

How to center a subview of UIView

I would use:

self.childView.center = CGPointMake(CGRectGetMidX(self.parentView.bounds),
                                    CGRectGetMidY(self.parentView.bounds));

I like to use the CGRect options...

SWIFT 3:

self.childView.center = CGPoint(x: self.parentView.bounds.midX,
                                        y: self.parentView.bounds.midY);

Compare two List<T> objects for equality, ignoring order

In addition to Guffa's answer, you could use this variant to have a more shorthanded notation.

public static bool ScrambledEquals<T>(this IEnumerable<T> list1, IEnumerable<T> list2)
{
  var deletedItems = list1.Except(list2).Any();
  var newItems = list2.Except(list1).Any();
  return !newItems && !deletedItems;          
}

Regular expression that matches valid IPv6 addresses

The following will validate IPv4, IPv6 (full and compressed), and IPv6v4 (full and compressed) addresses:

'/^(?>(?>([a-f0-9]{1,4})(?>:(?1)){7}|(?!(?:.*[a-f0-9](?>:|$)){8,})((?1)(?>:(?1)){0,6})?::(?2)?)|(?>(?>(?1)(?>:(?1)){5}:|(?!(?:.*[a-f0-9]:){6,})(?3)?::(?>((?1)(?>:(?1)){0,4}):)?)?(25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9]?[0-9])(?>\.(?4)){3}))$/iD'

Is it possible to get an Excel document's row count without loading the entire document into memory?

The solution suggested in this answer has been deprecated, and might no longer work.


Taking a look at the source code of OpenPyXL (IterableWorksheet) I've figured out how to get the column and row count from an iterator worksheet:

wb = load_workbook(path, use_iterators=True)
sheet = wb.worksheets[0]

row_count = sheet.get_highest_row() - 1
column_count = letter_to_index(sheet.get_highest_column()) + 1

IterableWorksheet.get_highest_column returns a string with the column letter that you can see in Excel, e.g. "A", "B", "C" etc. Therefore I've also written a function to translate the column letter to a zero based index:

def letter_to_index(letter):
    """Converts a column letter, e.g. "A", "B", "AA", "BC" etc. to a zero based
    column index.

    A becomes 0, B becomes 1, Z becomes 25, AA becomes 26 etc.

    Args:
        letter (str): The column index letter.
    Returns:
        The column index as an integer.
    """
    letter = letter.upper()
    result = 0

    for index, char in enumerate(reversed(letter)):
        # Get the ASCII number of the letter and subtract 64 so that A
        # corresponds to 1.
        num = ord(char) - 64

        # Multiply the number with 26 to the power of `index` to get the correct
        # value of the letter based on it's index in the string.
        final_num = (26 ** index) * num

        result += final_num

    # Subtract 1 from the result to make it zero-based before returning.
    return result - 1

I still haven't figured out how to get the column sizes though, so I've decided to use a fixed-width font and automatically scaled columns in my application.

How do I find out which DOM element has the focus?

document.activeElement may default to the <body> element if no focusable elements are in focus. Additionally, if an element is focused and the browser window is blurred, activeElement will continue to hold the focused element.

If either of these two behaviors are not desirable, consider a CSS-based approach: document.querySelector( ':focus' ).

Switch statement for greater-than/less-than

In my case (color-coding a percentage, nothing performance-critical), I quickly wrote this:

function findColor(progress) {
    const thresholds = [30, 60];
    const colors = ["#90B451", "#F9A92F", "#90B451"];

    return colors.find((col, index) => {
        return index >= thresholds.length || progress < thresholds[index];
    });
}

delete a column with awk or sed

Try using cut... its fast and easy

First you have repeated spaces, you can squeeze those down to a single space between columns if thats what you want with tr -s ' '

If each column already has just one delimiter between it, you can use cut -d ' ' -f-2 to print fields (columns) <= 2.

for example if your data is in a file input.txt you can do one of the following:

cat input.txt | tr -s ' ' | cut -d ' ' -f-2

Or if you better reason about this problem by removing the 3rd column you can write the following

cat input.txt | tr -s ' ' | cut -d ' ' --complement -f3

cut is pretty powerful, you can also extract ranges of bytes, or characters, in addition to columns

excerpt from the man page on the syntax of how to specify the list range

Each LIST is made up of one range, or many ranges separated by commas.
Selected input is written in the same order that it is read, and is
written exactly once. Each range is one of:

  N     N'th byte, character or field, counted from 1
  N-    from N'th byte, character or field, to end of line
  N-M   from N'th to M'th (included) byte, character or field
  -M    from first to M'th (included) byte, character or field

so you also could have said you want specific columns 1 and 2 with...

cat input.txt | tr -s ' ' | cut -d ' ' -f1,2

Bad File Descriptor with Linux Socket write() Bad File Descriptor C

I had this error too, my problem was in some part of code I didn't close file descriptor and in other part, I tried to open that file!! use close(fd) system call after you finished working on a file.

What's the best way to get the last element of an array without deleting it?

Another solution:

$array = array('a' => 'a', 'b' => 'b', 'c' => 'c');
$lastItem = $array[(array_keys($array)[(count($array)-1)])];
echo $lastItem;

How can I open an Excel file in Python?

Try the xlrd library.

[Edit] - from what I can see from your comment, something like the snippet below might do the trick. I'm assuming here that you're just searching one column for the word 'john', but you could add more or make this into a more generic function.

from xlrd import open_workbook

book = open_workbook('simple.xls',on_demand=True)
for name in book.sheet_names():
    if name.endswith('2'):
        sheet = book.sheet_by_name(name)

        # Attempt to find a matching row (search the first column for 'john')
        rowIndex = -1
        for cell in sheet.col(0): # 
            if 'john' in cell.value:
                break

        # If we found the row, print it
        if row != -1:
            cells = sheet.row(row)
            for cell in cells:
                print cell.value

        book.unload_sheet(name) 

How do I revert a Git repository to a previous commit?

For rollback (or to revert):

1. git revert --no-commit "commit-code-to-remove" HEAD
(e.g. git revert --no-commit d57a39d HEAD)
2. git commit
3. git push

Try the above two steps, and if you find this is what you want then git push.

If you find something wrong, do:

git revert --abort

Setting the focus to a text field

In a JFrame or JDialog you can always overwrite the setVisible() method, it works well. I haven't tried in a JPanel, but can be an alternative.

@Override
public void setVisible(boolean value) {
    super.setVisible(value);
    control.requestFocusInWindow();
}

sizing div based on window width

Try absolute positioning:

<div style="position:relative;width:100%;">
    <div id="help" style="
    position:absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    z-index:1;">
        <img src="/portfolio/space_1_header.png" border="0" style="width:100%;">
    </div>
</div>

Should I use 'border: none' or 'border: 0'?

In my point,

border:none is working but not valid w3c standard

so better we can use border:0;

Multiple Order By with LINQ

You can use the ThenBy and ThenByDescending extension methods:

foobarList.OrderBy(x => x.Foo).ThenBy( x => x.Bar)

How to make a countdown timer in Android?

just copy paste the following code........

MainActivity

package com.example.countdowntimer;

import java.util.concurrent.TimeUnit;
import android.app.Activity;
import android.os.Bundle;
import android.os.CountDownTimer;
import android.widget.TextView;


public class MainActivity extends Activity {


      TextView text1;

 private static final String FORMAT = "%02d:%02d:%02d";

 int seconds , minutes;

@Override
public void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);


    text1=(TextView)findViewById(R.id.textView1);

    new CountDownTimer(16069000, 1000) { // adjust the milli seconds here

        public void onTick(long millisUntilFinished) {

            text1.setText(""+String.format(FORMAT,
                    TimeUnit.MILLISECONDS.toHours(millisUntilFinished),
TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished) - TimeUnit.HOURS.toMinutes(
                    TimeUnit.MILLISECONDS.toHours(millisUntilFinished)),
  TimeUnit.MILLISECONDS.toSeconds(millisUntilFinished) - TimeUnit.MINUTES.toSeconds(
                      TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished))));              
        }

        public void onFinish() {
            text1.setText("done!");
        }
     }.start();             

  }

  }

activity_main.xml

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="vertical" >

<TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true"
    android:layout_marginLeft="34dp"
    android:layout_marginTop="58dp"
    android:text="Large Text"
    android:textAppearance="?android:attr/textAppearanceMedium" />

   </RelativeLayout>

Setting ANDROID_HOME enviromental variable on Mac OS X

In Terminal:

nano ~/.bash_profile 

Add lines:

export ANDROID_HOME=/YOUR_PATH_TO/android-sdk
export PATH=$ANDROID_HOME/platform-tools:$PATH
export PATH=$ANDROID_HOME/tools:$PATH

Check it worked:

source ~/.bash_profile
echo $ANDROID_HOME

Constructor overload in TypeScript

TypeScript allows you to declare overloads but you can only have one implementation and that implementation must have a signature that is compatible with all overloads. In your example, this can easily be done with an optional parameter as in,

interface IBox {    
    x : number;
    y : number;
    height : number;
    width : number;
}

class Box {
    public x: number;
    public y: number;
    public height: number;
    public width: number;

    constructor(obj?: IBox) {    
        this.x = obj && obj.x || 0
        this.y = obj && obj.y || 0
        this.height = obj && obj.height || 0
        this.width = obj && obj.width || 0;
    }   
}

or two overloads with a more general constructor as in,

interface IBox {    
    x : number;
    y : number;
    height : number;
    width : number;
}

class Box {
    public x: number;
    public y: number;
    public height: number;
    public width: number;

    constructor();
    constructor(obj: IBox); 
    constructor(obj?: any) {    
        this.x = obj && obj.x || 0
        this.y = obj && obj.y || 0
        this.height = obj && obj.height || 0
        this.width = obj && obj.width || 0;
    }   
}

PHP 7: Missing VCRUNTIME140.dll

Usually this is an error in your PHP configuration.

It's actually pretty easy to figure out what exactly is going on:

  • Create a small file (test.php) with the standard phpinfo() script
  • Open a command prompt
  • Start php manually using the small file, e.g. '"\program files\php\php.exe" test.php
  • Read the error messages :-)

Importing larger sql files into MySQL

3 things you have to do, if you are doing it locally:

in php.ini or php.cfg of your php installation

post_max_size=500M

upload_max_filesize=500M

memory_limit=900M

or set other values. Restart Apache.

OR

Use php big dump tool its best ever i have seen. its free and opensource

http://www.ozerov.de/bigdump/

Does the 'mutable' keyword have any purpose other than allowing the variable to be modified by a const function?

The mutable keyword is very useful when creating stubs for class test purposes. You can stub a const function and still be able to increase (mutable) counters or whatever test functionality you have added to your stub. This keeps the interface of the stubbed class intact.

Can I pass a JavaScript variable to another browser window?

Putting code to the matter, you can do this from the parent window:

var thisIsAnObject = {foo:'bar'};
var w = window.open("http://example.com");
w.myVariable = thisIsAnObject;

or this from the new window:

var myVariable = window.opener.thisIsAnObject;

I prefer the latter, because you will probably need to wait for the new page to load anyway, so that you can access its elements, or whatever you want.

Check if array is empty or null

I think it is dangerous to use $.isEmptyObject from jquery to check whether the array is empty, as @jesenko mentioned. I just met that problem.

In the isEmptyObject doc, it mentions:

The argument should always be a plain JavaScript Object

which you can determine by $.isPlainObject. The return of $.isPlainObject([]) is false.

Unable to start debugging on the web server. Could not start ASP.NET debugging VS 2010, II7, Win 7 x64

Try going to IIS and checking to make sure the App Pool you are using is started. A lot of times, you will produce an error that shuts down the app pool. You just need to right click and Start and you should be good to go.

How do I activate C++ 11 in CMake?

I am using

include(CheckCXXCompilerFlag)
CHECK_CXX_COMPILER_FLAG("-std=c++11" COMPILER_SUPPORTS_CXX11)
CHECK_CXX_COMPILER_FLAG("-std=c++0x" COMPILER_SUPPORTS_CXX0X)
if(COMPILER_SUPPORTS_CXX11)
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
elseif(COMPILER_SUPPORTS_CXX0X)
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++0x")
else()
        message(STATUS "The compiler ${CMAKE_CXX_COMPILER} has no C++11 support. Please use a different C++ compiler.")
endif()

But if you want to play with C++11, g++ 4.6.1 is pretty old. Try to get a newer g++ version.

Calling C++ class methods via a function pointer

A function pointer to a class member is a problem that is really suited to using boost::function. Small example:

#include <boost/function.hpp>
#include <iostream>

class Dog 
{
public:
   Dog (int i) : tmp(i) {}
   void bark ()
   {
      std::cout << "woof: " << tmp << std::endl;
   }
private:
   int tmp;
};



int main()
{
   Dog* pDog1 = new Dog (1);
   Dog* pDog2 = new Dog (2);

   //BarkFunction pBark = &Dog::bark;
   boost::function<void (Dog*)> f1 = &Dog::bark;

   f1(pDog1);
   f1(pDog2);
}

how do I get eclipse to use a different compiler version for Java?

Eclipse uses it's own internal compiler that can compile to several Java versions.

From Eclipse Help > Java development user guide > Concepts > Java Builder

The Java builder builds Java programs using its own compiler (the Eclipse Compiler for Java) that implements the Java Language Specification.

For Eclipse Mars.1 Release (4.5.1), this can target 1.3 to 1.8 inclusive.

When you configure a project:

[project-name] > Properties > Java Compiler > Compiler compliance level

This configures the Eclipse Java compiler to compile code to the specified Java version, typically 1.8 today.

Host environment variables, eg JAVA_HOME etc, are not used.

The Oracle/Sun JDK compiler is not used.

What's the right way to create a date in Java?

The excellent joda-time library is almost always a better choice than Java's Date or Calendar classes. Here's a few examples:

DateTime aDate = new DateTime(year, month, day, hour, minute, second);
DateTime anotherDate = new DateTime(anotherYear, anotherMonth, anotherDay, ...);
if (aDate.isAfter(anotherDate)) {...}
DateTime yearFromADate = aDate.plusYears(1);

Checking for NULL pointer in C/C++

Actually, I use both variants.

There are situations, where you first check for the validity of a pointer, and if it is NULL, you just return/exit out of a function. (I know this can lead to the discussion "should a function have only one exit point")

Most of the time, you check the pointer, then do what you want and then resolve the error case. The result can be the ugly x-times indented code with multiple if's.

In-place type conversion of a NumPy array

You can change the array type without converting like this:

a.dtype = numpy.float32

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

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

...applied to each member of your array.

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

- edit -

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

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

...then change the dtype when done.

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

import numpy

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

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

ORA-12514 TNS:listener does not currently know of service requested in connect descriptor

This really should be a comment to Brad Rippe's answer, but alas, not enough rep. That answer got me 90% of the way there. In my case, the installation and configuration of the databases put entries in the tnsnames.ora file for the databases I was running. First, I was able to connect to the database by setting the environment variables (Windows):

set ORACLE_SID=mydatabase
set ORACLE_HOME=C:\Oracle\product\11.2.0\dbhome_1

and then connecting using

sqlplus / as sysdba

Next, running the command from Brad Rippe's answer:

select value from v$parameter where name='service_names';

showed that the names didn't match exactly. The entries as created using Oracle's Database Configuration Assistant where originally:

MYDATABASE =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = mylaptop.mydomain.com)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = mydatabase.mydomain.com)
    )
  ) 

The service name from the query was just mydatabase rather than mydatabase.mydomain.com. I edited the tnsnames.ora file to just the base name without the domain portion so they looked like this:

MYDATABASE =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = mylaptop.mydomain.com)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = mydatabase)
    )
  ) 

I restarted the TNS Listener service (I often use lsnrctl stop and lsnrctl start from an administrator command window [or Windows Powershell] instead of the Services control panel, but both work.) After that, I was able to connect.

Call a function from another file?

Came across the same feature but I had to do the below to make it work.

If you are seeing 'ModuleNotFoundError: No module named', you probably need the dot(.) in front of the filename as below;

from .file import funtion

Ant if else condition?

You can also do this with ant contrib's if task.

<if>
    <equals arg1="${condition}" arg2="true"/>
    <then>
        <copy file="${some.dir}/file" todir="${another.dir}"/>
    </then>
    <elseif>
        <equals arg1="${condition}" arg2="false"/>
        <then>
            <copy file="${some.dir}/differentFile" todir="${another.dir}"/>
        </then>
    </elseif>
    <else>
        <echo message="Condition was neither true nor false"/>
    </else>
</if>

Best way to format integer as string with leading zeros?

You can use the zfill() method to pad a string with zeros:

In [3]: str(1).zfill(2)
Out[3]: '01'

Copy-item Files in Folders and subfolders in the same directory structure of source server using PowerShell

If you want to mirror same content from source to destination, try following one.

function CopyFilesToFolder ($fromFolder, $toFolder) {
    $childItems = Get-ChildItem $fromFolder
    $childItems | ForEach-Object {
         Copy-Item -Path $_.FullName -Destination $toFolder -Recurse -Force
    }
}

Test:

CopyFilesToFolder "C:\temp\q" "c:\temp\w"

How do I open an .exe from another C++ .exe?

You should always avoid using system() because

  • It is resource heavy
  • It defeats security -- you don't know you it's a valid command or does the same thing on every system, you could even start up programs you didn't intend to start up. The danger is that when you directly execute a program, it gets the same privileges as your program -- meaning that if, for example, you are running as system administrator then the malicious program you just inadvertently executed is also running as system administrator. If that doesn't scare you silly, check your pulse.
  • Anti virus programs hate it, your program could get flagged as a virus.

You should use CreateProcess().

You can use Createprocess() to just start up an .exe and creating a new process for it. The application will run independent from the calling application.

Here's an example I used in one of my projects:

#include <windows.h>

VOID startup(LPCTSTR lpApplicationName)
{
   // additional information
   STARTUPINFO si;     
   PROCESS_INFORMATION pi;

   // set the size of the structures
   ZeroMemory( &si, sizeof(si) );
   si.cb = sizeof(si);
   ZeroMemory( &pi, sizeof(pi) );

  // start the program up
  CreateProcess( lpApplicationName,   // the path
    argv[1],        // Command line
    NULL,           // Process handle not inheritable
    NULL,           // Thread handle not inheritable
    FALSE,          // Set handle inheritance to FALSE
    0,              // No creation flags
    NULL,           // Use parent's environment block
    NULL,           // Use parent's starting directory 
    &si,            // Pointer to STARTUPINFO structure
    &pi             // Pointer to PROCESS_INFORMATION structure (removed extra parentheses)
    );
    // Close process and thread handles. 
    CloseHandle( pi.hProcess );
    CloseHandle( pi.hThread );
}

EDIT: The error you are getting is because you need to specify the path of the .exe file not just the name. Openfile.exe probably doesn't exist.

Attach a body onload event with JS

This takes advantage of DOMContentLoaded - which fires before onload - but allows you to stick in all your unobtrusiveness...

window.onload - Dean Edwards - The blog post talks more about it - and here is the complete code copied from the comments of that same blog.

// Dean Edwards/Matthias Miller/John Resig

function init() {
  // quit if this function has already been called
  if (arguments.callee.done) return;

  // flag this function so we don't do the same thing twice
  arguments.callee.done = true;

  // kill the timer
  if (_timer) clearInterval(_timer);

  // do stuff
};

/* for Mozilla/Opera9 */
if (document.addEventListener) {
  document.addEventListener("DOMContentLoaded", init, false);
}

/* for Internet Explorer */
/*@cc_on @*/
/*@if (@_win32)
  document.write("<script id=__ie_onload defer src=javascript:void(0)><\/script>");
  var script = document.getElementById("__ie_onload");
  script.onreadystatechange = function() {
    if (this.readyState == "complete") {
      init(); // call the onload handler
    }
  };
/*@end @*/

/* for Safari */
if (/WebKit/i.test(navigator.userAgent)) { // sniff
  var _timer = setInterval(function() {
    if (/loaded|complete/.test(document.readyState)) {
      init(); // call the onload handler
    }
  }, 10);
}

/* for other browsers */
window.onload = init;

How do I put a border around an Android textview?

I found a better way to put a border around a TextView.

Use a nine-patch image for the background. It's pretty simple, the SDK comes with a tool to make the 9-patch image, and it involves absolutely no coding.

The link is http://developer.android.com/guide/topics/graphics/2d-graphics.html#nine-patch.

joining two select statements

You should use UNION if you want to combine different resultsets. Try the following:

(SELECT * 
 FROM ( SELECT * 
        FROM orders_products 
        INNER JOIN orders ON orders_products.orders_id = orders.orders_id  
        WHERE products_id = 181) AS A)
UNION 

(SELECT * 
 FROM ( SELECT * 
        FROM orders_products 
        INNER JOIN orders ON orders_products.orders_id = orders.orders_id 
        WHERE products_id = 180) AS B
ON A.orders_id=B.orders_id)

Change name of folder when cloning from GitHub?

Arrived here because my source repo had %20 in it which was creating local folders with %20 in them when using simplistic git clone <url>.

Easy solution:

git clone https://teamname.visualstudio.com/Project%20Name/_git/Repo%20Name "Repo Name"

How to check if keras tensorflow backend is GPU or CPU version?

Also you can check using Keras backend function:

from keras import backend as K
K.tensorflow_backend._get_available_gpus()

I test this on Keras (2.1.1)

Arduino Tools > Serial Port greyed out

sudo arduino is the only way I get the Arduino IDE working (serial port and upload) on ubuntu 12.04 (64) Indeed the serial port to use is /dev/ttyACM0 in my case too. The other two (ttyS4 and ttyS0) gave an error when trying to upload to Uno. Have fun

What is the symbol for whitespace in C?

The character representation of a Space is simply ' '.

void foo (const char *s)
{
    unsigned char c;
    ...
    if (c == ' ')
        ...
}

But if you are really looking for all whitespace, then C has a function (actually it's often a macro) for that:

#include <ctype.h>
...

void foo (const char *s)
{
    char c;
    ...
    if (isspace(c))
        ...
}

You can read about isspace here

If you really want to catch all non-printing characters, the function to use is isprint from the same library. This deals with all of the characters below 0x20 (the ASCII code for a space) and above 0x7E (0x7f is the code for DEL, and everything above that is an extension).

In raw code this is equivalent to:

if (c < ' ' || c >= 0x7f)
    // Deal with non-printing characters.

Using AngularJS date filter with UTC date

After some research I was able to find a good solution for converting UTC to local time, have a a look at the fiddle. Hope it help

https://jsfiddle.net/way2ajay19/2kramzng/20/

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>

<div ng-app ng-controller="MyCtrl">
  {{date | date:'yyyy-mm-dd hh:mm:ss' }}
</div>


<script>
function MyCtrl($scope) {
 $scope.d = "2017-07-21 19:47:00";
  $scope.d = $scope.d.replace(" ", 'T') + 'Z';
  $scope.date = new Date($scope.d);
}
</script>

HTTP Status 405 - Request method 'POST' not supported (Spring MVC)

I found the problem that was causing the HTTP error.

In the setFalse() function that is triggered by the Save button my code was trying to submit the form that contained the button.

        function setFalse(){
            document.getElementById("hasId").value ="false";
            document.deliveryForm.submit();
            document.submitForm.submit();

when I remove the document.submitForm.submit(); it works:

        function setFalse(){
            document.getElementById("hasId").value ="false";
            document.deliveryForm.submit()

@Roger Lindsjö Thank you for spotting my error where I wasn't passing on the right parameter!

How can I enable the MySQLi extension in PHP 7?

Let's use

mysqli_connect

instead of

mysql_connect

because mysql_connect isn't supported in PHP 7.

How to set the text color of TextView in code?

You should use:

holder.text.setTextColor(Color.RED);

You can use various functions from the Color class to get the same effect of course.

  • Color.parseColor (Manual) (like LEX uses)

    text.setTextColor(Color.parseColor("#FFFFFF"));
    
  • Color.rgb and Color.argb (Manual rgb) (Manual argb) (like Ganapathy uses)

    holder.text.setTextColor(Color.rgb(200,0,0));
    holder.text.setTextColor(Color.argb(0,200,0,0));
    
  • And of course, if you want to define your color in an XML file, you can do this:

    <color name="errorColor">#f00</color>
    

    because the getColor() function is deprecated1, you need to use it like so:

    ContextCompat.getColor(context, R.color.your_color);
    
  • You can also insert plain HEX, like so:

    myTextView.setTextColor(0xAARRGGBB);
    

    Where you have an alpha-channel first, then the color value.

Check out the complete manual of course, public class Color extends Object.


1This code used to be in here as well:

textView.setTextColor(getResources().getColor(R.color.errorColor));

This method is now deprecated in Android M. You can however use it from the contextCompat in the support library, as the example now shows.

How to delete stuff printed to console by System.out.println()?

Clearing screen in Java is not supported, but you can try some hacks to achieve this.

a) Use OS-depends command, like this for Windows:

Runtime.getRuntime().exec("cls");

b) Put bunch of new lines (this makes ilusion that screen is clear)

c) If you ever want to turn off System.out, you can try this:

System.setOut(new PrintStream(new OutputStream() {
    @Override public void write(int b) throws IOException {}
}));

Get width/height of SVG element

Use getBBox function

http://jsfiddle.net/Xkv3X/1/

var bBox = svg1.getBBox();
console.log('XxY', bBox.x + 'x' + bBox.y);
console.log('size', bBox.width + 'x' + bBox.height);

How to make the web page height to fit screen height

you can use css to set the body tag to these settings:

body
{
padding:0px;
margin:0px;
width:100%;
height:100%;
}

Convert categorical data in pandas dataframe

If your concern was only that you making a extra column and deleting it later, just dun use a new column at the first place.

dataframe = pd.DataFrame({'col1':[1,2,3,4,5], 'col2':list('abcab'),  'col3':list('ababb')})
dataframe.col3 = pd.Categorical.from_array(dataframe.col3).codes

You are done. Now as Categorical.from_array is deprecated, use Categorical directly

dataframe.col3 = pd.Categorical(dataframe.col3).codes

If you also need the mapping back from index to label, there is even better way for the same

dataframe.col3, mapping_index = pd.Series(dataframe.col3).factorize()

check below

print(dataframe)
print(mapping_index.get_loc("c"))

Can not deserialize instance of java.util.ArrayList out of VALUE_STRING

Setting this attribute to ObjectMapper instance works,

objectMapper.enable(DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY);

AttributeError: Module Pip has no attribute 'main'

It appears that pip did a refactor and moved main to internal. There is a comprehensive discussion about it here: https://github.com/pypa/pip/issues/5240

A workaround for me was to change

import pip
pip.main(...)

to

from pip._internal import main
main(...)

I recommend reading through the discussion, I'm not sure this is the best approach, but it worked for my purposes.

What is the difference between a HashMap and a TreeMap?

Along with sorted key store one another difference is with TreeMap, developer can give (String.CASE_INSENSITIVE_ORDER) with String keys, so then the comparator ignores case of key while performing comparison of keys on map access. This is not possible to give such option with HashMap - it is always case sensitive comparisons in HashMap.

What do 'lazy' and 'greedy' mean in the context of regular expressions?

Greedy means your expression will match as large a group as possible, lazy means it will match the smallest group possible. For this string:

abcdefghijklmc

and this expression:

a.*c

A greedy match will match the whole string, and a lazy match will match just the first abc.

The page cannot be displayed because an internal server error has occurred on server

I think the best first approach is to make sure to turn on detailed error messages via your web.config file, like this:

<configuration>
    <system.webServer>
        <httpErrors errorMode="Detailed"></httpErrors>
    </system.webServer>
</configuration>

After doing this, you should get a more detailed error message from the server.

In my particular case, the more detailed error pointed out that my <defaultDocument> section of the web.config file was not allowed at the folder level where I'd placed my web.config. It said

This configuration section cannot be used at this path. This happens when the section is locked at a parent level. Locking is either by default (overrideModeDefault="Deny"), or set explicitly by a location tag with overrideMode="Deny" or the legacy allowOverride="false". "

Hiding user input on terminal in Linux script

I always like to use Ansi escape characters:

echo -e "Enter your password: \x1B[8m"
echo -e "\x1B[0m"

8m makes text invisible and 0m resets text to "normal." The -e makes Ansi escapes possible.

The only caveat is that you can still copy and paste the text that is there, so you probably shouldn't use this if you really want security.

It just lets people not look at your passwords when you type them in. Just don't leave your computer on afterwards. :)


NOTE:

The above is platform independent as long as it supports Ansi escape sequences.

However, for another Unix solution, you could simply tell read to not echo the characters...

printf "password: "
let pass $(read -s)
printf "\nhey everyone, the password the user just entered is $pass\n"

Having the output of a console application in Visual Studio instead of the console

regarding System.Diagnostics.Debug producing a lot of "junk" in the Output window: You can turn that off by right clicking in the output window. E.g. there's an item "Module Load Messages" which you want to disable and an item "Program Output" which you want to keep.

Optional args in MATLAB functions

A simple way of doing this is via nargin (N arguments in). The downside is you have to make sure that your argument list and the nargin checks match.

It is worth remembering that all inputs are optional, but the functions will exit with an error if it calls a variable which is not set. The following example sets defaults for b and c. Will exit if a is not present.

function [ output_args ] = input_example( a, b, c )
if nargin < 1
  error('input_example :  a is a required input')
end

if nargin < 2
  b = 20
end

if nargin < 3
  c = 30
end
end

How to send authorization header with axios

On non-simple http requests your browser will send a "preflight" request (an OPTIONS method request) first in order to determine what the site in question considers safe information to send (see here for the cross-origin policy spec about this). One of the relevant headers that the host can set in a preflight response is Access-Control-Allow-Headers. If any of the headers you want to send were not listed in either the spec's list of whitelisted headers or the server's preflight response, then the browser will refuse to send your request.

In your case, you're trying to send an Authorization header, which is not considered one of the universally safe to send headers. The browser then sends a preflight request to ask the server whether it should send that header. The server is either sending an empty Access-Control-Allow-Headers header (which is considered to mean "don't allow any extra headers") or it's sending a header which doesn't include Authorization in its list of allowed headers. Because of this, the browser is not going to send your request and instead chooses to notify you by throwing an error.

Any Javascript workaround you find that lets you send this request anyways should be considered a bug as it is against the cross origin request policy your browser is trying to enforce for your own safety.

tl;dr - If you'd like to send Authorization headers, your server had better be configured to allow it. Set your server up so it responds to an OPTIONS request at that url with an Access-Control-Allow-Headers: Authorization header.

What is two way binding?

Actually emberjs supports two-way binding, which is one of the most powerful feature for a javascript MVC framework. You can check it out where it mentioning binding in its user guide.

for emberjs, to create two way binding is by creating a new property with the string Binding at the end, then specifying a path from the global scope:

App.wife = Ember.Object.create({
  householdIncome: 80000
});

App.husband = Ember.Object.create({
  householdIncomeBinding: 'App.wife.householdIncome'
});

App.husband.get('householdIncome'); // 80000

// Someone gets raise.
App.husband.set('householdIncome', 90000);
App.wife.get('householdIncome'); // 90000

Note that bindings don't update immediately. Ember waits until all of your application code has finished running before synchronizing changes, so you can change a bound property as many times as you'd like without worrying about the overhead of syncing bindings when values are transient.

Hope it helps in extend of original answer selected.

Convert date from 'Thu Jun 09 2011 00:00:00 GMT+0530 (India Standard Time)' to 'YYYY-MM-DD' in javascript

Above solutions will work only if its a string. Input type date, gives you output in javascript date object in some cases like if you use angular or so. That's why some people are getting error like "TypeError: str.split is not a function". It's a date object, so you should use functions of Date object in javascript to manipulate it. Example here:

var date = $scope.dateObj ; 
//dateObj is data bind to the ng-modal of input type dat.
console.log(date.getFullYear()); //this will give you full year eg : 1990
console.log(date.getDate()); //gives you the date from 1 to 31
console.log(date.getMonth() + 1); //getMonth will give month from 0 to 11 

Check the following link for reference:

Converting JSON to XML in Java

Underscore-java library has static method U.jsonToXml(jsonstring). I am the maintainer of the project. Live example

import com.github.underscore.lodash.U;

public class MyClass {
    public static void main(String args[]) {
        String json = "{\"name\":\"JSON\",\"integer\":1,\"double\":2.0,\"boolean\":true,\"nested\":{\"id\":42},\"array\":[1,2,3]}";  
        System.out.println(json); 
        String xml = U.jsonToXml(json);  
        System.out.println(xml); 
    }
}

Output:

{"name":"JSON","integer":1,"double":2.0,"boolean":true,"nested":{"id":42},"array":[1,2,3]}
<?xml version="1.0" encoding="UTF-8"?>
<root>
  <name>JSON</name>
  <integer number="true">1</integer>
  <double number="true">2.0</double>
  <boolean boolean="true">true</boolean>
  <nested>
    <id number="true">42</id>
  </nested>
  <array number="true">1</array>
  <array number="true">2</array>
  <array number="true">3</array>
</root>

How can I select all children of an element except the last child?

Make it simple:

You can apply your style to all the div and re-initialize the last one with :last-child:

for example in CSS:

.yourclass{
    border: 1px solid blue;
}
.yourclass:last-child{
    border: 0;
}

or in SCSS:

.yourclass{
    border: 1px solid rgba(255, 255, 255, 1);
    &:last-child{
        border: 0;
    }
}
  • easy to read/remember
  • fast to execute
  • browser compatible (IE9+ since it's still CSS3)

How to dismiss keyboard for UITextView with return key?

swift

func textView(textView: UITextView, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool {
    if text == "\n" {
        textView.resignFirstResponder()
    }
    return true
}

and configure

How to make use of ng-if , ng-else in angularJS

You can also try ternary operator. Something like this

{{data.id === 5 ? "it's true" : "it's false"}}

Change your html code little bit and try this hope so it will be work for you.

How can I simulate an array variable in MySQL?

This works fine for list of values:

SET @myArrayOfValue = '2,5,2,23,6,';

WHILE (LOCATE(',', @myArrayOfValue) > 0)
DO
SET @value = ELT(1, @myArrayOfValue);
    SET @STR = SUBSTRING(@myArrayOfValue, 1, LOCATE(',',@myArrayOfValue)-1);
    SET @myArrayOfValue = SUBSTRING(@myArrayOfValue, LOCATE(',', @myArrayOfValue) + 1);

    INSERT INTO `Demo` VALUES(@STR, 'hello');
END WHILE;

Trigger change event <select> using jquery

To select an option, use .val('value-of-the-option') on the select element. To trigger the change element, use .change() or .trigger('change').

The problems in your code are the comma instead of the dot in $('.check'),trigger('change'); and the fact that you call it before binding the event handler.

WPF - add static items to a combo box

You can also add items in code:

cboWhatever.Items.Add("SomeItem");

Also, to add something where you control display/value, (almost categorically needed in my experience) you can do so. I found a good stackoverflow reference here:

Key Value Pair Combobox in WPF

Sum-up code would be something like this:

ComboBox cboSomething = new ComboBox();
cboSomething.DisplayMemberPath = "Key";
cboSomething.SelectedValuePath = "Value";
cboSomething.Items.Add(new KeyValuePair<string, string>("Something", "WhyNot"));
cboSomething.Items.Add(new KeyValuePair<string, string>("Deus", "Why"));
cboSomething.Items.Add(new KeyValuePair<string, string>("Flirptidee", "Stuff"));
cboSomething.Items.Add(new KeyValuePair<string, string>("Fernum", "Blictor"));

Formatting DataBinder.Eval data

Text='<%# DateTime.Parse(Eval("LastLoginDate").ToString()).ToString("MM/dd/yyyy hh:mm tt") %>'

This works for the format as you want

Select only rows if its value in a particular column is less than the value in the other column

df[df$aged <= df$laclen, ] 

Should do the trick. The square brackets allow you to index based on a logical expression.

Conditionally displaying JSF components

Yes, use the rendered attribute.

<h:form rendered="#{some boolean condition}">

You usually tie it to the model rather than letting the model grab the component and manipulate it.

E.g.

<h:form rendered="#{bean.booleanValue}" />
<h:form rendered="#{bean.intValue gt 10}" />
<h:form rendered="#{bean.objectValue eq null}" />
<h:form rendered="#{bean.stringValue ne 'someValue'}" />
<h:form rendered="#{not empty bean.collectionValue}" />
<h:form rendered="#{not bean.booleanValue and bean.intValue ne 0}" />
<h:form rendered="#{bean.enumValue eq 'ONE' or bean.enumValue eq 'TWO'}" />

Note the importance of keyword based EL operators such as gt, ge, le and lt instead of >, >=, <= and < as angle brackets < and > are reserved characters in XML. See also this related Q&A: Error parsing XHTML: The content of elements must consist of well-formed character data or markup.

As to your specific use case, let's assume that the link is passing a parameter like below:

<a href="page.xhtml?form=1">link</a>

You can then show the form as below:

<h:form rendered="#{param.form eq '1'}">

(the #{param} is an implicit EL object referring to a Map representing the request parameters)

See also:

Reading HTTP headers in a Spring REST controller

Instead of taking the HttpServletRequest object in every method, keep in controllers' context by auto-wiring via the constructor. Then you can access from all methods of the controller.

public class OAuth2ClientController {
    @Autowired
    private OAuth2ClientService oAuth2ClientService;

    private HttpServletRequest request;

    @Autowired
    public OAuth2ClientController(HttpServletRequest request) {
        this.request = request;
    }

    @RequestMapping(method = RequestMethod.POST)
    public ResponseEntity<String> createClient(@RequestBody OAuth2Client client) {
        System.out.println(request.getRequestURI());
        System.out.println(request.getHeader("Content-Type"));

        return ResponseEntity.ok();
    }
}

What are the rules for calling the superclass constructor?

In C++, the no-argument constructors for all superclasses and member variables are called for you, before entering your constructor. If you want to pass them arguments, there is a separate syntax for this called "constructor chaining", which looks like this:

class Sub : public Base
{
  Sub(int x, int y)
  : Base(x), member(y)
  {
  }
  Type member;
};

If anything run at this point throws, the bases/members which had previously completed construction have their destructors called and the exception is rethrown to to the caller. If you want to catch exceptions during chaining, you must use a function try block:

class Sub : public Base
{
  Sub(int x, int y)
  try : Base(x), member(y)
  {
    // function body goes here
  } catch(const ExceptionType &e) {
    throw kaboom();
  }
  Type member;
};

In this form, note that the try block is the body of the function, rather than being inside the body of the function; this allows it to catch exceptions thrown by implicit or explicit member and base class initializations, as well as during the body of the function. However, if a function catch block does not throw a different exception, the runtime will rethrow the original error; exceptions during initialization cannot be ignored.

How to add style from code behind?

Try this:

Html Markup

<asp:HyperLink ID="HyperLink1" runat="server" NavigateUrl="#">HyperLink</asp:HyperLink>

Code

using System.Drawing;
using System.Web.UI;
using System.Web.UI.WebControls;

protected void Page_Load(object sender, EventArgs e)
{
    Style style = new Style();
    style.ForeColor = Color.Green;
    this.Page.Header.StyleSheet.CreateStyleRule(style, this, "#" + HyperLink1.ClientID + ":hover");
}

Is there a performance difference between CTE , Sub-Query, Temporary Table or Table Variable?

Just 2 things I think make it ALWAYS preferable to use a # Temp Table rather then a CTE are:

  1. You can not put a primary key on a CTE so the data being accessed by the CTE will have to traverse each one of the indexes in the CTE's tables rather then just accessing the PK or Index on the temp table.

  2. Because you can not add constraints, indexes and primary keys to a CTE they are more prone to bugs creeping in and bad data.


-onedaywhen yesterday

Here is an example where #table constraints can prevent bad data which is not the case in CTE's

DECLARE @BadData TABLE ( 
                       ThisID int
                     , ThatID int );
INSERT INTO @BadData
       ( ThisID
       , ThatID
       ) 
VALUES
       ( 1, 1 ),
       ( 1, 2 ),
       ( 2, 2 ),
       ( 1, 1 );

IF OBJECT_ID('tempdb..#This') IS NOT NULL
    DROP TABLE #This;
CREATE TABLE #This ( 
             ThisID int NOT NULL
           , ThatID int NOT NULL
                        UNIQUE(ThisID, ThatID) );
INSERT INTO #This
SELECT * FROM @BadData;
WITH This_CTE
     AS (SELECT *
           FROM @BadData)
     SELECT *
       FROM This_CTE;

Passing parameter to controller action from a Html.ActionLink

You are using incorrect overload. You should use this overload

public static MvcHtmlString ActionLink(
    this HtmlHelper htmlHelper,
    string linkText,
    string actionName,
    string controllerName,
    Object routeValues,
    Object htmlAttributes
) 

And the correct code would be

<%= Html.ActionLink("Create New Part", "CreateParts", "PartList", new { parentPartId = 0 }, null)%>

Note that extra parameter at the end. For the other overloads, visit LinkExtensions.ActionLink Method. As you can see there is no string, string, string, object overload that you are trying to use.

How to debug when Kubernetes nodes are in 'Not Ready' state

First, describe nodes and see if it reports anything:

$ kubectl describe nodes

Look for conditions, capacity and allocatable:

Conditions:
  Type              Status
  ----              ------
  OutOfDisk         False
  MemoryPressure    False
  DiskPressure      False
  Ready             True
Capacity:
 cpu:       2
 memory:    2052588Ki
 pods:      110
Allocatable:
 cpu:       2
 memory:    1950188Ki
 pods:      110

If everything is alright here, SSH into the node and observe kubelet logs to see if it reports anything. Like certificate erros, authentication errors etc.

If kubelet is running as a systemd service, you can use

$ journalctl -u kubelet

Copy file from source directory to binary directory using CMake

If you want to put the content of example into install folder after build:

code/
  src/
  example/
  CMakeLists.txt

try add the following to your CMakeLists.txt:

install(DIRECTORY example/ DESTINATION example)

How to 'update' or 'overwrite' a python list

I think it is more pythonic:

aList.remove(123)
aList.insert(0, 2014)

more useful:

def shuffle(list, to_delete, to_shuffle, index):
    list.remove(to_delete)
    list.insert(index, to_shuffle)
    return

list = ['a', 'b']
shuffle(list, 'a', 'c', 0)
print list
>> ['c', 'b']

How to declare a Fixed length Array in TypeScript

The javascript array has a constructor that accepts the length of the array:

let arr = new Array<number>(3);
console.log(arr); // [undefined × 3]

However, this is just the initial size, there's no restriction on changing that:

arr.push(5);
console.log(arr); // [undefined × 3, 5]

Typescript has tuple types which let you define an array with a specific length and types:

let arr: [number, number, number];

arr = [1, 2, 3]; // ok
arr = [1, 2]; // Type '[number, number]' is not assignable to type '[number, number, number]'
arr = [1, 2, "3"]; // Type '[number, number, string]' is not assignable to type '[number, number, number]'

getElementById returns null?

There could be many reason why document.getElementById doesn't work

  • You have an invalid ID

    ID and NAME tokens must begin with a letter ([A-Za-z]) and may be followed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods ("."). (resource: What are valid values for the id attribute in HTML?)

  • you used some id that you already used as <meta> name in your header (e.g. copyright, author... ) it looks weird but happened to me: if your 're using IE take a look at (resource: http://www.phpied.com/getelementbyid-description-in-ie/)

  • you're targeting an element inside a frame or iframe. In this case if the iframe loads a page within the same domain of the parent you should target the contentdocument before looking for the element (resource: Calling a specific id inside a frame)

  • you're simply looking to an element when the node is not effectively loaded in the DOM, or maybe it's a simple misspelling

I doubt you used same ID twice or more: in that case document.getElementById should return at least the first element

Android Studio with Google Play Services

Follow this article -> http://developer.android.com/google/play-services/setup.html

You should to choose Using Android Studio

enter image description here

Example Gradle file:

Note: Open the build.gradle file inside your application module directory.

apply plugin: 'com.android.application'

android {
    compileSdkVersion 20
    buildToolsVersion "20.0.0"

    defaultConfig {
        applicationId "{applicationId}"
        minSdkVersion 14
        targetSdkVersion 20
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            runProguard false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:20.+'
    compile 'com.google.android.gms:play-services:6.1.+'
}

You can find latest version of Google Play Services here: https://developer.android.com/google/play-services/index.html

Does Ruby have a string.startswith("abc") built in method?

Your question title and your question body are different. Ruby does not have a starts_with? method. Rails, which is a Ruby framework, however, does, as sepp2k states. See his comment on his answer for the link to the documentation for it.

You could always use a regular expression though:

if SomeString.match(/^abc/) 
   # SomeString starts with abc

^ means "start of string" in regular expressions

Opening database file from within SQLite command-line shell

You can simply specify the database file name in the command line:

bash-3.2 # sqlite3 UserDb.sqlite
SQLite version 3.16.2 2017-01-06 16:32:41
Enter ".help" for usage hints.

sqlite> .databases
main: /db/UserDb.sqlite

sqlite> .tables
accountLevelSettings  genres               syncedThumbs
collectionActivity    recordingFilter      thumbs
contentStatus         syncedContentStatus 

sqlite> select count(*) from genres;
10

Moreover, you can execute your query from the command line:

bash-3.2 # sqlite3 UserDb.sqlite 'select count(*) from genres'
10

You could attach another database file from the SQLite shell:

sqlite> attach database 'RelDb.sqlite' as RelDb;

sqlite> .databases
main: /db/UserDb.sqlite
RelDb: /db/RelDb_1.sqlite

sqlite> .tables
RelDb.collectionRelationship  contentStatus               
RelDb.contentRelationship     genres                      
RelDb.leagueRelationship      recordingFilter             
RelDb.localizedString         syncedContentStatus         
accountLevelSettings          syncedThumbs                
collectionActivity            thumbs                      

The tables from this 2nd database will be accessible via prefix of the database:

sqlite> select count(*) from RelDb.localizedString;
2442

But who knows how to specify multiple database files from the command line to execute the query from the command line?

Right way to reverse a pandas DataFrame?

What is the right way to reverse a pandas DataFrame?

TL;DR: df[::-1]

This is objectively IMO the best method for reversing a DataFrame, because it is a ONE step operation, also very readable (assuming familiarity with slice notation).


Long Version

I've found the ol' slicing trick df[::-1] (or the equivalent df.loc[::-1]1) to be the most concise and idiomatic way of reversing a DataFrame. This mirrors the python list reversal syntax lst[::-1] and is clear in its intent. With the loc syntax, you are also able to slice columns if required, so it is a bit more flexible.

Some points to consider while handling the index:

  • "what if I want to reverse the index as well?"

    • you're already done. df[::-1] reverses both the index and values.
  • "what if I want to drop the index from the result?"

  • "what if I want to keep the index untouched (IOW, only reverse the data, not the index)?"

    • this is somewhat unconventional because it implies the index isn't really relevant to the data. Perhaps consider removing it entirely? Although what you're asking for can technically be achieved using either df[:] = df[::-1] which creates an in-place update to df, or df.loc[::-1].set_index(df.index), which returns a copy.

1: df.loc[::-1] and df.iloc[::-1] are equivalent since the slicing syntax remains the same, whether you're reversing by position (iloc) or label (loc).


The Proof is in the Pudding

enter image description here

X-axis represents the dataset size. Y-axis represents time taken to reverse. No method scales as well as the slicing trick, it's all the way at the bottom of the graph. Benchmarking code for reference, plots generated using perfplot.


Comments on other solutions

  • df.reindex(index=df.index[::-1]) is clearly a popular solution, but on first glance, how obvious is it to an unfamiliar reader that this code is "reversing a DataFrame"? Additionally, this is reversing the index, then using that intermediate result to reindex, so this is essentially a TWO step operation (when it could've been just one).

  • df.sort_index(ascending=False) may work in most cases where you have a simple range index, but this assumes your index was sorted in ascending order and so doesn't generalize well.

  • PLEASE do not use iterrows. I see some options suggesting iterating in reverse. Whatever your use case, there is likely a vectorized method available, but if there isn't then you can use something a little more reasonable such as list comprehensions. See How to iterate over rows in a DataFrame in Pandas for more detail on why iterrows is an antipattern.

SVN: Is there a way to mark a file as "do not commit"?

Subversion does not have a built-in "do not commit" / "ignore on commit" feature, as of February 2016 / version 1.9. This answer is a non-ideal command-line workaround

As the OP states, TortoiseSVN has a built in changelist, "ignore-on-commit", which is automatically excluded from commits. The command-line client does not have this, so you need to use multiple changelists to accomplish this same behavior (with caveats):

  • one for work you want to commit [work]
  • one for things you want to ignore [ignore-on-commit]

Since there's precedent with TortoiseSVN, I use "ignore-on-commit" in my examples for the files I don't want to commit. I'll use "work" for the files I do, but you could pick any name you wanted.

First, add all files to a changelist named "work". This must be run from the root of your working copy:

svn cl work . -R

This will add all files in the working copy recursively to the changelist named "work". There is a disadvantage to this - as new files are added to the working copy, you'll need to specifically add the new files or they won't be included. Second, if you have to run this again you'll then need to re-add all of your "ignore-on-commit" files again. Not ideal - you could start maintaining your own 'ignore' list in a file as others have done.

Then, for the files you want to exclude:

svn cl ignore-on-commit path\to\file-to-ignore

Because files can only be in one changelist, running this addition after your previous "work" add will remove the file you want to ignore from the "work" changelist and put it in the "ignore-on-commit" changelist.

When you're ready to commit your modified files you do wish to commit, you'd then simply add "--cl work" to your commit:

svn commit --cl work -m "message"

Here's what a simple example looks like on my machine:

D:\workspace\trunk>svn cl work . -R
Skipped '.'
Skipped 'src'
Skipped 'src\conf'
A [work] src\conf\db.properties
Skipped 'src\java'
Skipped 'src\java\com'
Skipped 'src\java\com\corp'
Skipped 'src\java\com\corp\sample'
A [work] src\java\com\corp\sample\Main.java
Skipped 'src\java\com\corp\sample\controller'
A [work] src\java\com\corp\sample\controller\Controller.java
Skipped 'src\java\com\corp\sample\model'
A [work] src\java\com\corp\sample\model\Model.java
Skipped 'src\java\com\corp\sample\view'
A [work] src\java\com\corp\sample\view\View.java
Skipped 'src\resource'
A [work] src\resource\icon.ico
Skipped 'src\test'

D:\workspace\trunk>svn cl ignore-on-commit src\conf\db.properties
D [work] src\conf\db.properties
A [ignore-on-commit] src\conf\db.properties

D:\workspace\trunk>svn status

--- Changelist 'work':
        src\java\com\corp\sample\Main.java
        src\java\com\corp\sample\controller\Controller.java
        src\java\com\corp\sample\model\Model.java
M       src\java\com\corp\sample\view\View.java
        src\resource\icon.ico

--- Changelist 'ignore-on-commit':
M       src\conf\db.properties

D:\workspace\trunk>svn commit --cl work -m "fixed refresh issue"
Sending        src\java\com\corp\sample\view\View.java
Transmitting file data .done
Committing transaction...
Committed revision 9.

An alternative would be to simply add every file you wish to commit to a 'work' changelist, and not even maintain an ignore list, but this is a lot of work, too. Really, the only simple, ideal solution is if/when this gets implemented in SVN itself. There's a longstanding issue about this in the Subversion issue tracker, SVN-2858, in the event this changes in the future.

Passing bash variable to jq

Posting it here as it might help others. In string it might be necessary to pass the quotes to jq. To do the following with jq:

.items[] | select(.name=="string")

in bash you could do

EMAILID=$1
projectID=$(cat file.json | jq -r '.resource[] | select(.username=='\"$EMAILID\"') | .id')

essentially escaping the quotes and passing it on to jq

How to set the "Content-Type ... charset" in the request header using a HTML link

This is not possible from HTML on. The closest what you can get is the accept-charset attribute of the <form>. Only MSIE browser adheres that, but even then it is doing it wrong (e.g. CP1252 is actually been used when it says that it has sent ISO-8859-1). Other browsers are fully ignoring it and they are using the charset as specified in the Content-Type header of the response. Setting the character encoding right is basically fully the responsiblity of the server side. The client side should just send it back in the same charset as the server has sent the response in.

To the point, you should really configure the character encoding stuff entirely from the server side on. To overcome the inability to edit URIEncoding attribute, someone here on SO wrote a (complex) filter: Detect the URI encoding automatically in Tomcat. You may find it useful as well (note: I haven't tested it).


Update: Noted should be that the meta tag as given in your question is ignored when the content is been transferred over HTTP. Instead, the HTTP response Content-Type header will be used to determine the content type and character encoding. You can determine the HTTP header with for example Firebug, in the Net panel.

alt text

c++ boost split string

My best guess at why you had problems with the ----- covering your first result is that you actually read the input line from a file. That line probably had a \r on the end so you ended up with something like this:

-----------test2-------test3

What happened is the machine actually printed this:

test-------test2-------test3\r-------

That means, because of the carriage return at the end of test3, that the dashes after test3 were printed over the top of the first word (and a few of the existing dashes between test and test2 but you wouldn't notice that because they were already dashes).

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

Introduction

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

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

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

Turn off ajax / don't use remote command!

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

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

Generic JSF 2.x example

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

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

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

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

Generic JSF 1.x example

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

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

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

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

Common static file example

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

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

// ...

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

Common dynamic file example

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

E.g. iText PDF:

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

// ...

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

E.g. Apache POI HSSF:

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

// ...

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

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

Utility method

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

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

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

apache mod_rewrite is not working or not enabled

To get mod_rewrite to work for me in Apache 2.4, I had to add the "Require all granted" line below.

<Directory /var/www>
   # Required if running apache > 2.4
   Require all granted

   RewriteEngine on 
   RewriteRule ^cachebust-([a-z0-9]+)\/(.*) /$2 [L] 
 </Directory>

supposedly a similar requirement exists for Apache 2.2 as well, if you're using that:

<Directory /var/www>
   # Required if running apache 2.2
   Order allow,deny
   Allow from all

   RewriteEngine on 
   RewriteRule ^cachebust-([a-z0-9]+)\/(.*) /$2 [L] 
 </Directory>

Note that an ErrorDocument 404 directive can sometimes override these things as well, so if it's not working try commenting out your ErrorDocument directive and see if it works. The above example can be used to ensure a site isn't served from cache by including a subfolder in the path, though the files reside at the root of the server.

replacing text in a file with Python

Faster way of writing it would be...

in = open('path/to/input/file').read()
out = open('path/to/input/file', 'w')
replacements = {'zero':'0', 'temp':'bob', 'garbage':'nothing'}
for i in replacements.keys():
    in = in.replace(i, replacements[i])
out.write(in)
out.close

This eliminated a lot of the iterations that the other answers suggest, and will speed up the process for longer files.

How to configure Eclipse build path to use Maven dependencies?

Typically, you can copy the .classpath file from a working project since there isn’t anything project specific here assuming you’re structured as a standard Maven project.

Finding sum of elements in Swift array

Swift 4 example

class Employee {
    var salary: Int =  0
    init (_ salary: Int){
        self.salary = salary
    }
}

let employees = [Employee(100),Employee(300),Employee(600)]
var sumSalary = employees.reduce(0, {$0 + $1.salary}) //1000

Retrieve a single file from a repository

I use this

$ cat ~/.wgetrc
check_certificate = off

$ wget https://raw.github.com/jquery/jquery/master/grunt.js
HTTP request sent, awaiting response... 200 OK
Length: 11339 (11K) [text/plain]
Saving to: `grunt.js'

Jump into interface implementation in Eclipse IDE

Here's what I do:

  • In the interface, move the cursor to the method name. Press F4. => Type Hierarchy view appears
  • In the lower part of the view, the method should already be selected. In its toolbar, click "Lock view and show members in hierarchy" (should be the leftmost toolbar icon).
  • In the upper part of the view, you can browse through all implementations of the method.

The procedure isn't very quick, but it gives you a good overview.

I can't access http://localhost/phpmyadmin/

Run the Apache server, note down the port number(eg:8081) Open your browser and type localhost:8081(or apache's port number)

Creating a very simple linked list

Here is a good implementation.

  1. It is short, but implemented Add(x), Delete(x), Contain(x) and Print().
  2. It avoid special process when add to empty list or delete the first element. While most of other examples did special process when delete the first element.
  3. The list can contain any data type.

    using System;
    
    class Node<Type> : LinkedList<Type>
    {   // Why inherit from LinkedList? A: We need to use polymorphism.
        public Type value;
        public Node(Type value) { this.value = value; }
    }
    class LinkedList<Type>
    {   
        Node<Type> next;  // This member is treated as head in class LinkedList, but treated as next element in class Node.
        /// <summary> if x is in list, return previos pointer of x. (We can see any class variable as a pointer.)
        /// if not found, return the tail of the list. </summary>
        protected LinkedList<Type> Previos(Type x)
        {
            LinkedList<Type> p = this;      // point to head
            for (; p.next != null; p = p.next)
                if (p.next.value.Equals(x))
                    return p;               // find x, return the previos pointer.
            return p;                       // not found, p is the tail.
        }
        /// <summary> return value: true = success ; false = x not exist </summary>
        public bool Contain(Type x) { return Previos(x).next != null ? true : false; }
        /// <summary> return value: true = success ; false = fail to add. Because x already exist. 
        /// </summary> // why return value? If caller want to know the result, they don't need to call Contain(x) before, the action waste time.
        public bool Add(Type x)
        {
            LinkedList<Type> p = Previos(x);
            if (p.next != null)             // Find x already in list
                return false;
            p.next = new Node<Type>(x);
            return true;
        }
        /// <summary> return value: true = success ; false = x not exist </summary>
        public bool Delete(Type x)
        {
            LinkedList<Type> p = Previos(x);
            if (p.next == null)
                return false;
            //Node<Type> node = p.next;
            p.next = p.next.next;
            //node.Dispose();       // GC dispose automatically.
            return true;
        }
        public void Print()
        {
            Console.Write("List: ");
            for (Node<Type> node = next; node != null; node = node.next)
                Console.Write(node.value.ToString() + " ");
            Console.WriteLine();
        }
    }
    class Test
    {
        static void Main()
        {
            LinkedList<int> LL = new LinkedList<int>();
            if (!LL.Contain(0)) // Empty list
                Console.WriteLine("0 is not exist.");
            LL.Print();
            LL.Add(0);      // Add to empty list
            LL.Add(1); LL.Add(2); // attach to tail
            LL.Add(2);      // duplicate add, 2 is tail.
            if (LL.Contain(0))// Find existed element which is head
                Console.WriteLine("0 is exist.");
            LL.Print();
            LL.Delete(0);   // Delete head
            LL.Delete(2);   // Delete tail
            if (!LL.Delete(0)) // Delete non-exist element
                Console.WriteLine("0 is not exist.");
            LL.Print();
            Console.ReadLine();
        }
    }
    

By the way, the implementation in http://www.functionx.com/csharp1/examples/linkedlist.htm have some problem:

  1. Delete() will fail when there is only 1 element. (Throw exception at line "Head.Next = Current.Next;" because Current is null.)
  2. Delete(position) will fail when deleting first element, In other words, call Delete(0) will fail.

C# if/then directives for debug vs release

I got to thinking about a better way. It dawned on me that #if blocks are effectively comments in other configurations (assuming DEBUG or RELEASE; but true with any symbol)

public class Mytest
    {
        public DateTime DateAndTimeOfTransaction;
    }

    public void ProcessCommand(Mytest Command)
        {
            CheckMyCommandPreconditions(Command);
            // do more stuff with Command...
        }

        [Conditional("DEBUG")]
        private static void CheckMyCommandPreconditions(Mytest Command)
        {
            if (Command.DateAndTimeOfTransaction > DateTime.Now)
                throw new InvalidOperationException("DateTime expected to be in the past");
        }

How to send string from one activity to another?

Say there is EditText et1 in ur MainActivity and u wanna pass this to SecondActivity

String s=et1.getText().toString();
Bundle basket= new Bundle();
basket.putString("abc", s);
Intent a=new Intent(MainActivity.this,SecondActivity.class);
a.putExtras(basket);
startActivity(a);

now in Second Activity, say u wanna put the string passed from EditText et1 to TextView txt1 of SecondActivity

Bundle gt=getIntent().getExtras();
str=gt.getString("abc");
txt1.setText(str);

How to use <DllImport> in VB.NET?

Imports System.Runtime.InteropServices

Two dimensional array list

Here's how to make and print a 2D Multi-Dimensional Array using the ArrayList Object.

import java.util.ArrayList;

public class TwoD_ArrayListExample {
    static public ArrayList<ArrayList<String>> gameBoard = new ArrayList<ArrayList<String>>();

    public static void main(String[] args) {
        insertObjects();
        printTable(gameBoard);
    }

    public static void insertObjects() {
        for (int rowNum = 0; rowNum != 8; rowNum++) {
            ArrayList<String> oneRow = new ArrayList<String>();
            gameBoard.add(rowNum, oneRow);

            for (int columnNum = 0; columnNum != 8; columnNum++) {
                String description= "Description of Objects: row= "+ rowNum + ", column= "+ columnNum;
                    oneRow.add(columnNum, description);
            }
        }
    }

    // The printTable method prints the table to the console
    private static void printTable(ArrayList<ArrayList<String>> table) {
        for (int row = 0; row != 8; row++) {
            for (int col = 0; col != 8; col++) {
                System.out.println("Printing:               row= "+ row+ ", column= "+ col);
                System.out.println(table.get(row).get(col).toString());
            }
        }
        System.out.println("\n");
    }
}

Node.js: what is ENOSPC error and how to solve?

On Linux, this is likely to be a limit on the number of file watches.

The development server uses inotify to implement hot-reloading. The inotify API allows the development server to watch files and be notified when they change.

The default inotify file watch limit varies from distribution to distribution (8192 on Fedora). The needs of the development server often exceeds this limit.

The best approach is to try increasing the file watch limit temporarily, then making that a permanent configuration change if you're happy with it. Note, though, that this changes your entire system's configuration, not just node.

To view your current limit:

sysctl fs.inotify.max_user_watches

To temporarily set a new limit:

# this limit will revert after reset
sudo sysctl fs.inotify.max_user_watches=524288
sudo sysctl -p
# now restart the server and see if it works

To set a permanent limit:

echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf
sudo sysctl -p

Replace values in list using Python

This might help...

test_list = [5, 8]
test_list[0] = None
print test_list
#prints [None, 8]

JPA eager fetch does not join

"mxc" is right. fetchType just specifies when the relation should be resolved.

To optimize eager loading by using an outer join you have to add

@Fetch(FetchMode.JOIN)

to your field. This is a hibernate specific annotation.

How do I get the color from a hexadecimal color code using .NET?

I needed to convert a HEX color code to a System.Drawing.Color, specifically a shade of Alice Blue as a background on a WPF form and found it took longer than expected to find the answer:

using System.Windows.Media;

--

System.Drawing.Color myColor = System.Drawing.ColorTranslator.FromHtml("#EFF3F7");
this.Background = new SolidColorBrush(System.Windows.Media.Color.FromArgb(myColor.A, myColor.R, myColor.G, myColor.B));

Set focus on textbox in WPF

txtCompanyID.Focusable = true;
Keyboard.Focus(txtCompanyID);

msdn:

There can be only one element on the whole desktop that has keyboard focus. In WPF, the element that has keyboard focus will have IsKeyboardFocused set to true.

You could break after the setting line and check the value of IsKeyboardFocused property. Also check if you really reach that line or maybe you set some other element to get focus after that.

How to "EXPIRE" the "HSET" child key in redis?

There is a Redisson java framework which implements hash Map object with entry TTL support. It uses hmap and zset Redis objects under the hood. Usage example:

RMapCache<Integer, String> map = redisson.getMapCache('map');
map.put(1, 30, TimeUnit.DAYS); // this entry expires in 30 days

This approach is quite useful.

Datatable select method ORDER BY clause

Use

datatable.select("col1='test'","col1 ASC")

Then before binding your data to the grid or repeater etc, use this

datatable.defaultview.sort()

That will solve your problem.

Richtextbox wpf binding

There is a much easier way!

You can easily create an attached DocumentXaml (or DocumentRTF) property which will allow you to bind the RichTextBox's document. It is used like this, where Autobiography is a string property in your data model:

<TextBox Text="{Binding FirstName}" />
<TextBox Text="{Binding LastName}" />
<RichTextBox local:RichTextBoxHelper.DocumentXaml="{Binding Autobiography}" />

Voila! Fully bindable RichTextBox data!

The implementation of this property is quite simple: When the property is set, load the XAML (or RTF) into a new FlowDocument. When the FlowDocument changes, update the property value.

This code should do the trick:

using System.IO;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
public class RichTextBoxHelper : DependencyObject
{
    public static string GetDocumentXaml(DependencyObject obj)
    {
        return (string)obj.GetValue(DocumentXamlProperty);
    }

    public static void SetDocumentXaml(DependencyObject obj, string value)
    {
        obj.SetValue(DocumentXamlProperty, value);
    }

    public static readonly DependencyProperty DocumentXamlProperty =
        DependencyProperty.RegisterAttached(
            "DocumentXaml",
            typeof(string),
            typeof(RichTextBoxHelper),
            new FrameworkPropertyMetadata
            {
                BindsTwoWayByDefault = true,
                PropertyChangedCallback = (obj, e) =>
                {
                    var richTextBox = (RichTextBox)obj;

                    // Parse the XAML to a document (or use XamlReader.Parse())
                    var xaml = GetDocumentXaml(richTextBox);
                    var doc = new FlowDocument();
                    var range = new TextRange(doc.ContentStart, doc.ContentEnd);

                    range.Load(new MemoryStream(Encoding.UTF8.GetBytes(xaml)),
                          DataFormats.Xaml);

                    // Set the document
                    richTextBox.Document = doc;

                    // When the document changes update the source
                    range.Changed += (obj2, e2) =>
                    {
                        if (richTextBox.Document == doc)
                        {
                            MemoryStream buffer = new MemoryStream();
                            range.Save(buffer, DataFormats.Xaml);
                            SetDocumentXaml(richTextBox,
                                Encoding.UTF8.GetString(buffer.ToArray()));
                        }
                    };
                }
            });
}

The same code could be used for TextFormats.RTF or TextFormats.XamlPackage. For XamlPackage you would have a property of type byte[] instead of string.

The XamlPackage format has several advantages over plain XAML, especially the ability to include resources such as images, and it is more flexible and easier to work with than RTF.

It is hard to believe this question sat for 15 months without anyone pointing out the easy way to do this.

DataGridView AutoFit and Fill

You need to use the DataGridViewColumn.AutoSizeMode property.

You can use one of these values for column 0 and 1:

AllCells: The column width adjusts to fit the contents of all cells in the column, including the header cell.
AllCellsExceptHeader: The column width adjusts to fit the contents of all cells in the column, excluding the header cell.
DisplayedCells: The column width adjusts to fit the contents of all cells in the column that are in rows currently displayed onscreen, including the header cell.
DisplayedCellsExceptHeader: The column width adjusts to fit the contents of all cells in the column that are in rows currently displayed onscreen, excluding the header cell.

Then you use the Fill value for column 2

The column width adjusts so that the widths of all columns exactly fills the display area of the control...

this.DataGridView1.Columns[0].AutoSizeMode = DataGridViewAutoSizeColumnMode.DisplayedCells;
this.DataGridView1.Columns[1].AutoSizeMode = DataGridViewAutoSizeColumnMode.DisplayedCells;
this.DataGridView1.Columns[2].AutoSizeMode = DataGridViewAutoSizeColumnMode.Fill;

As pointed out by other users, the default value can be set at datagridview level with DataGridView.AutoSizeColumnsMode property.

this.DataGridView1.Columns[0].AutoSizeMode = DataGridViewAutoSizeColumnMode.DisplayedCells;
this.DataGridView1.Columns[1].AutoSizeMode = DataGridViewAutoSizeColumnMode.DisplayedCells;

could be:

this.DataGridView1.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.DisplayedCells;

Important note:

If your grid is bound to a datasource and columns are auto-generated (AutoGenerateColumns property set to True), you need to use the DataBindingComplete event to apply style AFTER columns have been created.


In some scenarios (change cells value by code for example), I had to call DataGridView1.AutoResizeColumns(); to refresh the grid.

How to define dimens.xml for every different screen size in android?

I've uploaded a simple java program which takes your project location and the dimension file you want as input. Based on that, it would output the corresponding dimension file in the console. Here's the link to it:

https://github.com/akeshwar/Dimens-for-different-screens-in-Android/blob/master/Main.java

Here's the full code for the reference:

public class Main {


    /**
     * You can change your factors here. The current factors are in accordance with the official documentation.
     */
    private static final double LDPI_FACTOR = 0.375;
    private static final double MDPI_FACTOR = 0.5;
    private static final double HDPI_FACTOR = 0.75;
    private static final double XHDPI_FACTOR = 1.0;
    private static final double XXHDPI_FACTOR = 1.5;
    private static final double XXXHDPI_FACTOR = 2.0;

    private static double factor;

    public static void main(String[] args) throws IOException {


        Scanner in = new Scanner(System.in);
        System.out.println("Enter the location of the project/module");
        String projectPath = in.nextLine();

        System.out.println("Which of the following dimension file do you want?\n1. ldpi \n2. mdpi \n3. hdpi \n4. xhdpi \n5. xxhdpi \n6. xxxhdpi");

        int dimenType = in.nextInt();

        switch (dimenType) {
            case 1: factor = LDPI_FACTOR;
                break;
            case 2: factor = MDPI_FACTOR;
                break;
            case 3: factor = HDPI_FACTOR;
                break;
            case 4: factor = XHDPI_FACTOR;
                break;
            case 5: factor = XXHDPI_FACTOR;
                break;
            case 6: factor = XXXHDPI_FACTOR;
                break;
            default:
                factor = 1.0;
        }

        //full path = "/home/akeshwar/android-sat-bothIncluded-notintegrated/code/tpr-5-5-9/princetonReview/src/main/res/values/dimens.xml"
        //location of the project or module = "/home/akeshwar/android-sat-bothIncluded-notintegrated/code/tpr-5-5-9/princetonReview/"


        /**
         * In case there is some I/O exception with the file, you can directly copy-paste the full path to the file here:
         */
        String fullPath = projectPath + "/src/main/res/values/dimens.xml";

        FileInputStream fstream = new FileInputStream(fullPath);
        BufferedReader br = new BufferedReader(new InputStreamReader(fstream));

        String strLine;

        while ((strLine = br.readLine()) != null)   {
            modifyLine(strLine);
        }
        br.close();

    }

    private static void modifyLine(String line) {

        /**
         * Well, this is how I'm detecting if the line has some dimension value or not.
         */
        if(line.contains("p</")) {
            int endIndex = line.indexOf("p</");

            //since indexOf returns the first instance of the occurring string. And, the actual dimension would follow after the first ">" in the screen
            int begIndex = line.indexOf(">");

            String prefix = line.substring(0, begIndex+1);
            String root = line.substring(begIndex+1, endIndex-1);
            String suffix = line.substring(endIndex-1,line.length());


            /**
             * Now, we have the root. We can use it to create different dimensions. Root is simply the dimension number.
             */

            double dimens = Double.parseDouble(root);
            dimens = dimens*factor*1000;
            dimens = (double)((int)dimens);
            dimens = dimens/1000;
            root = dimens + "";

            System.out.println(prefix + " " +  root + " " + suffix );

        }

        System.out.println(line);
    }
}

PHP function overloading

PHP does not support overloading for now. Hope this will be implemented in the other versions like other programming languages.

Checkout this library, This will allow you to use PHP Overloading in terms of closures. https://github.com/Sahil-Gulati/Overloading

How to validate IP address in Python?

I have to give a great deal of credit to Markus Jarderot for his post - the majority of my post is inspired from his.

I found that Markus' answer still fails some of the IPv6 examples in the Perl script referenced by his answer.

Here is my regex that passes all of the examples in that Perl script:

r"""^
     \s* # Leading whitespace
     # Zero-width lookaheads to reject too many quartets
     (?:
        # 6 quartets, ending IPv4 address; no wildcards
        (?:[0-9a-f]{1,4}(?::(?!:))){6}
             (?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)
        (?:\.(?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)){3}
      |
        # 0-5 quartets, wildcard, ending IPv4 address
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,4}[0-9a-f]{1,4})?
        (?:::(?!:))
             (?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)
        (?:\.(?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)){3}
      |
        # 0-4 quartets, wildcard, 0-1 quartets, ending IPv4 address
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,3}[0-9a-f]{1,4})?
        (?:::(?!:))
        (?:[0-9a-f]{1,4}(?::(?!:)))?
             (?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)
        (?:\.(?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)){3}
      |
        # 0-3 quartets, wildcard, 0-2 quartets, ending IPv4 address
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,2}[0-9a-f]{1,4})?
        (?:::(?!:))
        (?:[0-9a-f]{1,4}(?::(?!:))){0,2}
             (?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)
        (?:\.(?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)){3}
      |
        # 0-2 quartets, wildcard, 0-3 quartets, ending IPv4 address
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,1}[0-9a-f]{1,4})?
        (?:::(?!:))
        (?:[0-9a-f]{1,4}(?::(?!:))){0,3}
             (?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)
        (?:\.(?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)){3}
      |
        # 0-1 quartets, wildcard, 0-4 quartets, ending IPv4 address
        (?:[0-9a-f]{1,4}){0,1}
        (?:::(?!:))
        (?:[0-9a-f]{1,4}(?::(?!:))){0,4}
             (?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)
        (?:\.(?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)){3}
      |
        # wildcard, 0-5 quartets, ending IPv4 address
        (?:::(?!:))
        (?:[0-9a-f]{1,4}(?::(?!:))){0,5}
             (?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)
        (?:\.(?:25[0-4]|2[0-4]\d|1\d\d|[1-9]\d|\d)){3}
      |
        # 8 quartets; no wildcards
        (?:[0-9a-f]{1,4}(?::(?!:))){7}[0-9a-f]{1,4}
      |
        # 0-7 quartets, wildcard
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,6}[0-9a-f]{1,4})?
        (?:::(?!:))
      |
        # 0-6 quartets, wildcard, 0-1 quartets
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,5}[0-9a-f]{1,4})?
        (?:::(?!:))
        (?:[0-9a-f]{1,4})?
      |
        # 0-5 quartets, wildcard, 0-2 quartets
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,4}[0-9a-f]{1,4})?
        (?:::(?!:))
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,1}[0-9a-f]{1,4})?
      |
        # 0-4 quartets, wildcard, 0-3 quartets
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,3}[0-9a-f]{1,4})?
        (?:::(?!:))
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,2}[0-9a-f]{1,4})?
      |
        # 0-3 quartets, wildcard, 0-4 quartets
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,2}[0-9a-f]{1,4})?
        (?:::(?!:))
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,3}[0-9a-f]{1,4})?
      |
        # 0-2 quartets, wildcard, 0-5 quartets
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,1}[0-9a-f]{1,4})?
        (?:::(?!:))
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,4}[0-9a-f]{1,4})?
      |
        # 0-1 quartets, wildcard, 0-6 quartets
        (?:[0-9a-f]{1,4})?
        (?:::(?!:))
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,5}[0-9a-f]{1,4})?
      |
        # wildcard, 0-7 quartets
        (?:::(?!:))
        (?:(?:[0-9a-f]{1,4}(?::(?!:))){0,6}[0-9a-f]{1,4})?
     )
     (?:/(?:1(?:2[0-7]|[01]\d)|\d\d?))? # With an optional CIDR routing prefix (0-128)
     \s* # Trailing whitespace
    $"""

I also put together a Python script to test all of those IPv6 examples; it's here on Pastebin because it was too large to post here.

You can run the script with test result and example arguments in the form of "[result]=[example]", so like:

python script.py Fail=::1.2.3.4: pass=::127.0.0.1 false=::: True=::1

or you can simply run all of the tests by specifying no arguments, so like:

python script.py

Anyway, I hope this helps somebody else!

How to download a file from my server using SSH (using PuTTY on Windows)

try this scp -r -P2222 [email protected]:/home2/kwazy/www/utrecht-connected.nl /Desktop

Another easier option if you're going to be pulling files left and right is to just use an SFTP client like WinSCP. Then you're not typing out 100 characters every time you want to pull something, just drag and drop.

Edit: Just noticed /Desktop probably isn't where you're looking to download the file to. Should be something like C:\Users\you\Desktop

How to pass extra variables in URL with WordPress

To make the round trip "The WordPress Way" on the "front-end" (doesn't work in the context of wp-admin), you need to use 3 WordPress functions:

  • add_query_arg() - to create the URL with your new query variable ('c' in your example)
  • the query_vars filter - to modify the list of public query variables that WordPress knows about (this only works on the front-end, because the WP Query is not used on the back end - wp-admin - so this will also not be available in admin-ajax)
  • get_query_var() - to retrieve the value of your custom query variable passed in your URL.

Note: there's no need to even touch the superglobals ($_GET) if you do it this way.

Example

On the page where you need to create the link / set the query variable:

if it's a link back to this page, just adding the query variable

<a href="<?php echo esc_url( add_query_arg( 'c', $my_value_for_c ) )?>">

if it's a link to some other page

<a href="<?php echo esc_url( add_query_arg( 'c', $my_value_for_c, site_url( '/some_other_page/' ) ) )?>">

In your functions.php, or some plugin file or custom class (front-end only):

function add_custom_query_var( $vars ){
  $vars[] = "c";
  return $vars;
}
add_filter( 'query_vars', 'add_custom_query_var' );

On the page / function where you wish to retrieve and work with the query var set in your URL:

$my_c = get_query_var( 'c' );

On the Back End (wp-admin)

On the back end we don't ever run wp(), so the main WP Query does not get run. As a result, there are no query vars and the query_vars hook is not run.

In this case, you'll need to revert to the more standard approach of examining your $_GET superglobal. The best way to do this is probably:

$my_c = filter_input( INPUT_GET, "c", FILTER_SANITIZE_STRING );

though in a pinch you could do the tried and true

$my_c = isset( $_GET['c'] ? $_GET['c'] : "";

or some variant thereof.

npm - how to show the latest version of a package

You can see all the version of a module with npm view. eg: To list all versions of bootstrap including beta.

npm view bootstrap versions

But if the version list is very big it will truncate. An --json option will print all version including beta versions as well.

npm view bootstrap versions --json

If you want to list only the stable versions not the beta then use singular version

npm view bootstrap@* versions

Or

npm view bootstrap@* versions --json

And, if you want to see only latest version then here you go.

npm view bootstrap version