Programs & Examples On #Params

0

Android set height and width of Custom view programmatically

This is a Kotlin based version, assuming that the parent view is an instance of LinearLayout.

someView.layoutParams = LinearLayout.LayoutParams(100, 200)

This allows to set the width and height (100 and 200) in a single line.

How to pass parameters to $http in angularjs?

Here is a simple mathed to pass values from a route provider

//Route Provider
$routeProvider.when("/page/:val1/:val2/:val3",{controller:pageCTRL, templateUrl: 'pages.html'});


//Controller
$http.get( 'page.php?val1='+$routeParams.val1 +'&val2='+$routeParams.val2 +'&val3='+$routeParams.val3 , { cache: true})
        .then(function(res){
            //....
        })

Why use the params keyword?

Using params allows you to call the function with no arguments. Without params:

static public int addTwoEach(int[] args)
{
    int sum = 0;

    foreach (var item in args)
    {
        sum += item + 2;
    }

    return sum;
}

addtwoEach(); // throws an error

Compare with params:

static public int addTwoEach(params int[] args)
{
    int sum = 0;

    foreach (var item in args)
    {
        sum += item + 2;
    }

    return sum;
}

addtwoEach(); // returns 0

Generally, you can use params when the number of arguments can vary from 0 to infinity, and use an array when numbers of arguments vary from 1 to infinity.

How to use glOrtho() in OpenGL?

Have a look at this picture: Graphical Projections enter image description here

The glOrtho command produces an "Oblique" projection that you see in the bottom row. No matter how far away vertexes are in the z direction, they will not recede into the distance.

I use glOrtho every time I need to do 2D graphics in OpenGL (such as health bars, menus etc) using the following code every time the window is resized:

glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0.0f, windowWidth, windowHeight, 0.0f, 0.0f, 1.0f);

This will remap the OpenGL coordinates into the equivalent pixel values (X going from 0 to windowWidth and Y going from 0 to windowHeight). Note that I've flipped the Y values because OpenGL coordinates start from the bottom left corner of the window. So by flipping, I get a more conventional (0,0) starting at the top left corner of the window rather.

Note that the Z values are clipped from 0 to 1. So be careful when you specify a Z value for your vertex's position, it will be clipped if it falls outside that range. Otherwise if it's inside that range, it will appear to have no effect on the position except for Z tests.

How to set the value for Radio Buttons When edit?

For those who might be in need for a solution in pug template engine and NodeJs back-end, you can use this:

If values are not boolean(IE: true or false), code below works fine:

input(type='radio' name='sex' value='male' checked=(dbResult.sex ==='male') || (dbResult.sex === 'newvalue') )
input(type='radio' name='sex' value='female' checked=(dbResult.sex ==='female) || (dbResult.sex === 'newvalue'))

If values are boolean(ie: true or false), use this instead:

input(type='radio' name='isInsurable' value='true' checked=singleModel.isInsurable || (singleModel.isInsurable === 'true') )
input(type='radio' name='isInsurable' value='false' checked=!singleModel.isInsurable || (singleModel.isInsurable === 'false'))

the reason for this || operator is to re-display new values if editing fails due to validation error and you have a logic to send back the new values to your front-end

Inserting NOW() into Database with CodeIgniter's Active Record

I typically use triggers to handle timestamps but I think this may work.

$data = array(
    'name' => $name,
    'email' => $email
);

$this->db->set('time', 'NOW()', FALSE);
$this->db->insert('mytable', $data);

How is returning the output of a function different from printing it?

Print simply prints out the structure to your output device (normally the console). Nothing more. To return it from your function, you would do:

def autoparts():
  parts_dict = {}
  list_of_parts = open('list_of_parts.txt', 'r')
  for line in list_of_parts:
        k, v = line.split()
        parts_dict[k] = v
  return parts_dict

Why return? Well if you don't, that dictionary dies (gets garbage collected) and is no longer accessible as soon as this function call ends. If you return the value, you can do other stuff with it. Such as:

my_auto_parts = autoparts() 
print(my_auto_parts['engine']) 

See what happened? autoparts() was called and it returned the parts_dict and we stored it into the my_auto_parts variable. Now we can use this variable to access the dictionary object and it continues to live even though the function call is over. We then printed out the object in the dictionary with the key 'engine'.

For a good tutorial, check out dive into python. It's free and very easy to follow.

Using sudo with Python script

  • Use -S option in the sudo command which tells to read the password from 'stdin' instead of the terminal device.

  • Tell Popen to read stdin from PIPE.

  • Send the Password to the stdin PIPE of the process by using it as an argument to communicate method. Do not forget to add a new line character, '\n', at the end of the password.

sp = Popen(cmd , shell=True, stdin=PIPE)
out, err = sp.communicate(_user_pass+'\n')   

Replace a string in shell script using a variable

Not specific to the question, but for folks who need the same kind of functionality expanded for clarity from previous answers:

# create some variables
str="someFileName.foo"
find=".foo"
replace=".bar"
# notice the the str isn't prefixed with $
#    this is just how this feature works :/
result=${str//$find/$replace}
echo $result    
# result is: someFileName.bar

str="someFileName.sally"
find=".foo"
replace=".bar"
result=${str//$find/$replace}
echo $result    
# result is: someFileName.sally because ".foo" was not found

LINQ query to find if items in a list are contained in another list

var test2NotInTest1 = test2.Where(t2 => test1.Count(t1 => t2.Contains(t1))==0);

Faster version as per Tim's suggestion:

var test2NotInTest1 = test2.Where(t2 => !test1.Any(t1 => t2.Contains(t1)));

When to use Hadoop, HBase, Hive and Pig?

I worked on Lambda architecture processing Real time and Batch loads. Real time processing is needed where fast decisions need to be taken in case of Fire alarm send by sensor or fraud detection in case of banking transactions. Batch processing is needed to summarize data which can be feed into BI systems.

we used Hadoop ecosystem technologies for above applications.

Real Time Processing

Apache Storm: Stream Data processing, Rule application

HBase: Datastore for serving Realtime dashboard

Batch Processing Hadoop: Crunching huge chunk of data. 360 degrees overview or adding context to events. Interfaces or frameworks like Pig, MR, Spark, Hive, Shark help in computing. This layer needs scheduler for which Oozie is good option.

Event Handling layer

Apache Kafka was first layer to consume high velocity events from sensor. Kafka serves both Real Time and Batch analytics data flow through Linkedin connectors.

Java 8 Distinct by property

If you want to List of Persons following would be the simple way

Set<String> set = new HashSet<>(persons.size());
persons.stream().filter(p -> set.add(p.getName())).collect(Collectors.toList());

Additionally, if you want to find distinct or unique list of names, not Person , you can do using following two method as well.

Method 1: using distinct

persons.stream().map(x->x.getName()).distinct.collect(Collectors.toList());

Method 2: using HashSet

Set<E> set = new HashSet<>();
set.addAll(person.stream().map(x->x.getName()).collect(Collectors.toList()));

Difference between using Throwable and Exception in a try catch

The first one catches all subclasses of Throwable (this includes Exception and Error), the second one catches all subclasses of Exception.

Error is programmatically unrecoverable in any way and is usually not to be caught, except for logging purposes (which passes it through again). Exception is programmatically recoverable. Its subclass RuntimeException indicates a programming error and is usually not to be caught as well.

How to unpackage and repackage a WAR file

Adapting from the above answers, this works for Tomcat, but can be adapted for JBoss as well or any container:

sudo -u tomcat /opt/tomcat/bin/shutdown.sh
cd /opt/tomcat/webapps
sudo mkdir tmp; cd tmp
sudo jar -xvf ../myapp.war
#make edits...
sudo vi WEB-INF/classes/templates/fragments/header.html
sudo vi WEB-INF/classes/application.properties
#end of making edits
sudo jar -cvf myapp0.0.1.war *
sudo cp myapp0.0.1.war ..
cd ..
sudo chown tomcat:tomcat myapp0.0.1.war
sudo rm -rf tmp
sudo -u tomcat /opt/tomcat/bin/startup.sh

Can I pass parameters by reference in Java?

Can I pass parameters by reference in Java?

No.

Why ? Java has only one mode of passing arguments to methods: by value.

Note:

For primitives this is easy to understand: you get a copy of the value.

For all other you get a copy of the reference and this is called also passing by value.

It is all in this picture:

enter image description here

Cannot change version of project facet Dynamic Web Module to 3.0?

This Problem With version right click on the project->properties->Project Facets->right click on Dynamic Web Module->unlock it-> uncheck->select 2.5 version->Apply->Update the maven

Private class declaration

Private outer class would be useless as nothing can access it.

See more details:

Java: Why can we define a top level class as private?

Is there a REAL performance difference between INT and VARCHAR primary keys?

At HauteLook, we changed many of our tables to use natural keys. We did experience a real-world increase in performance. As you mention, many of our queries now use less joins which makes the queries more performant. We will even use a composite primary key if it makes sense. That being said, some tables are just easier to work with if they have a surrogate key.

Also, if you are letting people write interfaces to your database, a surrogate key can be helpful. The 3rd party can rely on the fact that the surrogate key will change only in very rare circumstances.

How to edit one specific row in Microsoft SQL Server Management Studio 2008?

How to edit one specific row/tuple in Server Management Studio 2008/2012/2014/2016

Step 1: Right button mouse > Select "Edit Top 200 Rows"

Edit top 200 rows

Step 2: Navigate to Query Designer > Pane > SQL (Shortcut: Ctrl+3)

Navigate to Query Designer > Pane > SQL

Step 3: Modify the query

Modify the query

Step 4: Right button mouse > Select "Execute SQL" (Shortcut: Ctrl+R)

enter image description here

Detect If Browser Tab Has Focus

While searching about this problem, I found a recommendation that Page Visibility API should be used. Most modern browsers support this API according to Can I Use: http://caniuse.com/#feat=pagevisibility.

Here's a working example (derived from this snippet):

$(document).ready(function() {
  var hidden, visibilityState, visibilityChange;

  if (typeof document.hidden !== "undefined") {
    hidden = "hidden", visibilityChange = "visibilitychange", visibilityState = "visibilityState";
  } else if (typeof document.msHidden !== "undefined") {
    hidden = "msHidden", visibilityChange = "msvisibilitychange", visibilityState = "msVisibilityState";
  }

  var document_hidden = document[hidden];

  document.addEventListener(visibilityChange, function() {
    if(document_hidden != document[hidden]) {
      if(document[hidden]) {
        // Document hidden
      } else {
        // Document shown
      }

      document_hidden = document[hidden];
    }
  });
});

Update: The example above used to have prefixed properties for Gecko and WebKit browsers, but I removed that implementation because these browsers have been offering Page Visibility API without a prefix for a while now. I kept Microsoft specific prefix in order to stay compatible with IE10.

Parse JSON from JQuery.ajax success data

you can use the jQuery parseJSON method:

var Data = $.parseJSON(response);

Java Set retain order?

The Set interface does not provide any ordering guarantees.

Its sub-interface SortedSet represents a set that is sorted according to some criterion. In Java 6, there are two standard containers that implement SortedSet. They are TreeSet and ConcurrentSkipListSet.

In addition to the SortedSet interface, there is also the LinkedHashSet class. It remembers the order in which the elements were inserted into the set, and returns its elements in that order.

Python: 'break' outside loop

Because break can only be used inside a loop. It is used to break out of a loop (stop the loop).

How to split long commands over multiple lines in PowerShell

You can use the backtick operator:

& "C:\Program Files\IIS\Microsoft Web Deploy\msdeploy.exe" `
    -verb:sync `
    -source:contentPath="c:\workspace\xxx\master\Build\_PublishedWebsites\xxx.Web" `
    -dest:contentPath="c:\websites\xxx\wwwroot\,computerName=192.168.1.1,username=administrator,password=xxx"

That's still a little too long for my taste, so I'd use some well-named variables:

$msdeployPath = "C:\Program Files\IIS\Microsoft Web Deploy\msdeploy.exe"
$verbArg = '-verb:sync'
$sourceArg = '-source:contentPath="c:\workspace\xxx\master\Build\_PublishedWebsites\xxx.Web"'
$destArg = '-dest:contentPath="c:\websites\xxx\wwwroot\,computerName=192.168.1.1,username=administrator,password=xxx"'

& $msdeployPath $verbArg $sourceArg $destArg

Convert objective-c typedef to its string equivalent

I would use the compiler's # string token (along with macros to make it all more compact):

#define ENUM_START              \
            NSString* ret;      \
            switch(value) {

#define ENUM_CASE(evalue)       \
            case evalue:        \
                ret = @#evalue; \
                break;

#define ENUM_END                \
            }                   \
            return ret;

NSString*
_CvtCBCentralManagerStateToString(CBCentralManagerState value)
{
    ENUM_START
        ENUM_CASE(CBCentralManagerStateUnknown)
        ENUM_CASE(CBCentralManagerStateResetting)
        ENUM_CASE(CBCentralManagerStateUnsupported)
        ENUM_CASE(CBCentralManagerStateUnauthorized)
        ENUM_CASE(CBCentralManagerStatePoweredOff)
        ENUM_CASE(CBCentralManagerStatePoweredOn)
    ENUM_END
}

Convert Pandas Column to DateTime

Use the to_datetime function, specifying a format to match your data.

raw_data['Mycol'] =  pd.to_datetime(raw_data['Mycol'], format='%d%b%Y:%H:%M:%S.%f')

tomcat - CATALINA_BASE and CATALINA_HOME variables

If you are running multiple instances of Tomcat on a single host you should set CATALINA_BASE to be equal to the .../tomcat_instance1 or .../tomcat_instance2 directory as appropriate for each instance and the CATALINA_HOME environment variable to the common Tomcat installation whose files will be shared between the two instances.

The CATALINA_BASE environment is optional if you are running a single Tomcat instance on the host and will default to CATALINA_HOME in that case. If you are running multiple instances as you are it should be provided.

There is a pretty good description of this setup in the RUNNING.txt file in the root of the Apache Tomcat distribution under the heading Advanced Configuration - Multiple Tomcat Instances

Add column to SQL Server

Adding a column using SSMS or ALTER TABLE .. ADD will not drop any existing data.

NodeJS: How to get the server's port?

You might be looking for process.env.PORT. This allows you to dynamically set the listening port using what are called "environment variables". The Node.js code would look like this:

const port = process.env.PORT || 3000; 
app.listen(port, () => {console.log(`Listening on port ${port}...`)}); 

You can even manually set the dynamic variable in the terminal using export PORT=5000, or whatever port you want.

Persist javascript variables across pages?

You could use the window’s name window.name to store the information. This is known as JavaScript session. But it only works as long as the same window/tab is used.

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

Good Question & Matt's was a good answer. To expand on the syntax a little if the oldtable has an identity a user could run the following:

SELECT col1, col2, IDENTITY( int ) AS idcol
INTO #newtable
FROM oldtable

That would be if the oldtable was scripted something as such:

CREATE TABLE [dbo].[oldtable]
(
    [oldtableID] [numeric](18, 0) IDENTITY(1,1) NOT NULL,
    [col1] [nvarchar](50) NULL,
    [col2] [numeric](18, 0) NULL,
)

execJs: 'Could not find a JavaScript runtime' but execjs AND therubyracer are in Gemfile

In your gemfile add:

gem 'execjs'
gem 'therubyracer', :platforms => :ruby

For more details: ExecJS and could not find a JavaScript runtime

Format numbers in JavaScript similar to C#

To further jfriend00's answer (I dont't have enough points to comment) I have extended his/her answer to the following:

_x000D_
_x000D_
function log(args) {_x000D_
    var str = "";_x000D_
    for (var i = 0; i < arguments.length; i++) {_x000D_
        if (typeof arguments[i] === "object") {_x000D_
            str += JSON.stringify(arguments[i]);_x000D_
        } else {_x000D_
            str += arguments[i];_x000D_
        }_x000D_
    }_x000D_
    var div = document.createElement("div");_x000D_
    div.innerHTML = str;_x000D_
    document.body.appendChild(div);_x000D_
}_x000D_
_x000D_
Number.prototype.addCommas = function (str) {_x000D_
    if (str === undefined) {_x000D_
     str = this;_x000D_
    }_x000D_
    _x000D_
    var parts = (str + "").split("."),_x000D_
        main = parts[0],_x000D_
        len = main.length,_x000D_
        output = "",_x000D_
        first = main.charAt(0),_x000D_
        i;_x000D_
    _x000D_
    if (first === '-') {_x000D_
        main = main.slice(1);_x000D_
        len = main.length;    _x000D_
    } else {_x000D_
       first = "";_x000D_
    }_x000D_
    i = len - 1;_x000D_
    while(i >= 0) {_x000D_
        output = main.charAt(i) + output;_x000D_
        if ((len - i) % 3 === 0 && i > 0) {_x000D_
            output = "," + output;_x000D_
        }_x000D_
        --i;_x000D_
    }_x000D_
    // put sign back_x000D_
    output = first + output;_x000D_
    // put decimal part back_x000D_
    if (parts.length > 1) {_x000D_
        output += "." + parts[1];_x000D_
    }_x000D_
    return output;_x000D_
}_x000D_
_x000D_
var testCases = [_x000D_
    1, 12, 123, -1234, 12345, 123456, -1234567, 12345678, 123456789,_x000D_
    -1.1, 12.1, 123.1, 1234.1, -12345.1, -123456.1, -1234567.1, 12345678.1, 123456789.1_x000D_
];_x000D_
 _x000D_
for (var i = 0; i < testCases.length; i++) {_x000D_
 log(testCases[i].addCommas());_x000D_
}_x000D_
 _x000D_
/*for (var i = 0; i < testCases.length; i++) {_x000D_
    log(Number.addCommas(testCases[i]));_x000D_
}*/
_x000D_
_x000D_
_x000D_

How to map and remove nil values in Ruby

You could use compact:

[1, nil, 3, nil, nil].compact
=> [1, 3] 

I'd like to remind people that if you're getting an array containing nils as the output of a map block, and that block tries to conditionally return values, then you've got code smell and need to rethink your logic.

For instance, if you're doing something that does this:

[1,2,3].map{ |i|
  if i % 2 == 0
    i
  end
}
# => [nil, 2, nil]

Then don't. Instead, prior to the map, reject the stuff you don't want or select what you do want:

[1,2,3].select{ |i| i % 2 == 0 }.map{ |i|
  i
}
# => [2]

I consider using compact to clean up a mess as a last-ditch effort to get rid of things we didn't handle correctly, usually because we didn't know what was coming at us. We should always know what sort of data is being thrown around in our program; Unexpected/unknown data is bad. Anytime I see nils in an array I'm working on, I dig into why they exist, and see if I can improve the code generating the array, rather than allow Ruby to waste time and memory generating nils then sifting through the array to remove them later.

'Just my $%0.2f.' % [2.to_f/100]

Proper way to exit command line program?

if you do ctrl-z and then type exit it will close background applications.

Ctrl+Q is another good way to kill the application.

How to monitor network calls made from iOS Simulator

It seems this may have recently been added. Clicking command + control + z on the simulator will pop up a debug menu. From that menu, click Inspect. Inspect will present tabs. Click the network tab and that will show all network requests being made.

Check if null Boolean is true results in exception

as your variable bool is pointing to a null, you will always get a NullPointerException, you need to initialize the variable first somewhere with a not null value, and then modify it.

Mongodb: Failed to connect to 127.0.0.1:27017, reason: errno:10061

Here are the steps to solve this issue:

  1. Just go to your MongoDB bin folder and run the mongod.exe file.
  2. Navigate to your mongodb bin folder via Command prompt and start mongo by typing "mongo"

Read a Csv file with powershell and capture corresponding data

So I figured out what is wrong with this statement:

Import-Csv H:\Programs\scripts\SomeText.csv |`

(Original)

Import-Csv H:\Programs\scripts\SomeText.csv -Delimiter "|"

(Proposed, You must use quotations; otherwise, it will not work and ISE will give you an error)

It requires the -Delimiter "|", in order for the variable to be populated with an array of items. Otherwise, Powershell ISE does not display the list of items.

I cannot say that I would recommend the | operator, since it is used to pipe cmdlets into one another.

I still cannot get the if statement to return true and output the values entered via the prompt.

If anyone else can help, it would be great. I still appreciate the post, it has been very helpful!

"google is not defined" when using Google Maps V3 in Firefox remotely

I faced 'google is not defined' several time. Probably Google Script has some problem not to be loaded well with FF-addon BTW. FF has restart option ( like window reboot ) Help > restart with Add-ons Disabled

CSS container div not getting height

It is not that easier?

.c {
    overflow: auto;
}

link button property to open in new tab?

Here is your Tag.

<asp:LinkButton ID="LinkButton1" runat="server">Open Test Page</asp:LinkButton>

Here is your code on the code behind.

LinkButton1.Attributes.Add("href","../Test.aspx")
LinkButton1.Attributes.Add("target","_blank")

Hope this will be helpful for someone.

Edit To do the same with a link button inside a template field, use the following code.

Use GridView_RowDataBound event to find Link button.

Dim LB as LinkButton = e.Row.FindControl("LinkButton1")         
LB.Attributes.Add("href","../Test.aspx")  
LB.Attributes.Add("target","_blank")

How to insert new row to database with AUTO_INCREMENT column without specifying column names?

For some databases, you can just explicitly insert a NULL into the auto_increment column:

INSERT INTO table_name VALUES (NULL, 'my name', 'my group')

Get Mouse Position

I am doing something like this to get mouse coordinates using Robot, I use these coordinates further in few of the games I am developing:

public class ForMouseOnly {
    public static void main(String[] args) throws InterruptedException {
        int x = MouseInfo.getPointerInfo().getLocation().x;
        int y = MouseInfo.getPointerInfo().getLocation().y;
        while (true) {

            if (x != MouseInfo.getPointerInfo().getLocation().x || y != MouseInfo.getPointerInfo().getLocation().y) {
                System.out.println("(" + MouseInfo.getPointerInfo().getLocation().x + ", "
                        + MouseInfo.getPointerInfo().getLocation().y + ")");
                x = MouseInfo.getPointerInfo().getLocation().x;
                y = MouseInfo.getPointerInfo().getLocation().y;
            }
        }
    }
}

How to parse data in JSON format?

Sometimes your json is not a string. For example if you are getting a json from a url like this:

j = urllib2.urlopen('http://site.com/data.json')

you will need to use json.load, not json.loads:

j_obj = json.load(j)

(it is easy to forget: the 's' is for 'string')

jquery select element by xpath

First create an xpath selector function.

function _x(STR_XPATH) {
    var xresult = document.evaluate(STR_XPATH, document, null, XPathResult.ANY_TYPE, null);
    var xnodes = [];
    var xres;
    while (xres = xresult.iterateNext()) {
        xnodes.push(xres);
    }

    return xnodes;
}

To use the xpath selector with jquery, you can do like this:

$(_x('/html/.//div[@id="text"]')).attr('id', 'modified-text');

Hope this can help.

Resync git repo with new .gitignore file

I might misunderstand, but are you trying to delete files newly ignored or do you want to ignore new modifications to these files ? In this case, the thing is working.

If you want to delete ignored files previously commited, then use

git rm –cached `git ls-files -i –exclude-standard`
git commit -m 'clean up'

ORDER BY items must appear in the select list if SELECT DISTINCT is specified

Try this:

ORDER BY 1, 2

OR

ORDER BY rsc.RadioServiceCodeId, rsc.RadioServiceCode + ' - ' + rsc.RadioService

Using Mockito to test abstract classes

What really makes me feel bad about mocking abstract classes is the fact, that neither the default constructor YourAbstractClass() gets called (missing super() in mock) nor seems there to be any way in Mockito to default initialize mock properties (e.g List properties with empty ArrayList or LinkedList).

My abstract class (basically the class source code gets generated) does NOT provide a dependency setter injection for list elements, nor a constructor where it initializes the list elements (which I tried to add manually).

Only the class attributes use default initialization:

private List<MyGenType> dep1 = new ArrayList<MyGenType>();
private List<MyGenType> dep2 = new ArrayList<MyGenType>();

So there is NO way to mock an abstract class without using a real object implementation (e.g inner class definition in unit test class, overriding abstract methods) and spying the real object (which does proper field initialization).

Too bad that only PowerMock would help here further.

How to bind RadioButtons to an enum?

You could use a more generic converter

public class EnumBooleanConverter : IValueConverter
{
  #region IValueConverter Members
  public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
  {
    string parameterString = parameter as string;
    if (parameterString == null)
      return DependencyProperty.UnsetValue;

    if (Enum.IsDefined(value.GetType(), value) == false)
      return DependencyProperty.UnsetValue;

    object parameterValue = Enum.Parse(value.GetType(), parameterString);

    return parameterValue.Equals(value);
  }

  public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
  {
    string parameterString = parameter as string;
    if (parameterString == null)
        return DependencyProperty.UnsetValue;

    return Enum.Parse(targetType, parameterString);
  }
  #endregion
}

And in the XAML-Part you use:

<Grid>
    <Grid.Resources>
      <l:EnumBooleanConverter x:Key="enumBooleanConverter" />
    </Grid.Resources>
    <StackPanel >
      <RadioButton IsChecked="{Binding Path=VeryLovelyEnum, Converter={StaticResource enumBooleanConverter}, ConverterParameter=FirstSelection}">first selection</RadioButton>
      <RadioButton IsChecked="{Binding Path=VeryLovelyEnum, Converter={StaticResource enumBooleanConverter}, ConverterParameter=TheOtherSelection}">the other selection</RadioButton>
      <RadioButton IsChecked="{Binding Path=VeryLovelyEnum, Converter={StaticResource enumBooleanConverter}, ConverterParameter=YetAnotherOne}">yet another one</RadioButton>
    </StackPanel>
</Grid>

Is there an equivalent for var_dump (PHP) in Javascript?

I used the first answer, but I felt was missing a recursion in it.

The result was this:

function dump(obj) {
    var out = '';
    for (var i in obj) {
        if(typeof obj[i] === 'object'){
            dump(obj[i]);
        }else{
            out += i + ": " + obj[i] + "\n";
        }
    }

    var pre = document.createElement('pre');
    pre.innerHTML = out;
    document.body.appendChild(pre);
}

How to fetch data from local JSON file on react native?

Since React Native 0.4.3 you can read your local JSON file like this:

const customData = require('./customData.json');

and then access customData like a normal JS object.

How to filter an array of objects based on values in an inner array with jq?

Here is another solution which uses any/2

map(select(any(.Names[]; contains("data"))|not)|.Id)[]

with the sample data and the -r option it produces

cb94e7a42732b598ad18a8f27454a886c1aa8bbba6167646d8f064cd86191e2b
a4b7e6f5752d8dcb906a5901f7ab82e403b9dff4eaaeebea767a04bac4aada19

Python 101: Can't open file: No such file or directory

I resolved this problem by navigating to C:\Python27\Scripts folder and then run file.py file instead of C:\Python27 folder

How to view the current heap size that an application is using?

You can use jconsole (standard with most JDKs) to check heap sizes of any java process.

XPath selecting a node with some attribute value equals to some other node's attribute value

I think this is what you want:

/grand/parent/child[@id="#grand"]

How do I launch a Git Bash window with particular working directory using a script?

This is the command which can be executed directly in Run dialog box (shortcut is win+R) and also works well saved as a .bat script:

cmd /c (start /d "/path/to/dir" bash --login) && exit

Request UAC elevation from within a Python script?

Just adding this answer in case others are directed here by Google Search as I was. I used the elevate module in my Python script and the script executed with Administrator Privileges in Windows 10.

https://pypi.org/project/elevate/

Pass a list to a function to act as multiple arguments

Since Python 3.5 you can unpack unlimited amount of lists.

PEP 448 - Additional Unpacking Generalizations

So this will work:

a = ['1', '2', '3', '4']
b = ['5', '6']
function_that_needs_strings(*a, *b)

javascript pushing element at the beginning of an array

Use .unshift() to add to the beginning of an array.

TheArray.unshift(TheNewObject);

See MDN for doc on unshift() and here for doc on other array methods.

FYI, just like there's .push() and .pop() for the end of the array, there's .shift() and .unshift() for the beginning of the array.

What is the difference between join and merge in Pandas?

pandas.merge() is the underlying function used for all merge/join behavior.

DataFrames provide the pandas.DataFrame.merge() and pandas.DataFrame.join() methods as a convenient way to access the capabilities of pandas.merge(). For example, df1.merge(right=df2, ...) is equivalent to pandas.merge(left=df1, right=df2, ...).

These are the main differences between df.join() and df.merge():

  1. lookup on right table: df1.join(df2) always joins via the index of df2, but df1.merge(df2) can join to one or more columns of df2 (default) or to the index of df2 (with right_index=True).
  2. lookup on left table: by default, df1.join(df2) uses the index of df1 and df1.merge(df2) uses column(s) of df1. That can be overridden by specifying df1.join(df2, on=key_or_keys) or df1.merge(df2, left_index=True).
  3. left vs inner join: df1.join(df2) does a left join by default (keeps all rows of df1), but df.merge does an inner join by default (returns only matching rows of df1 and df2).

So, the generic approach is to use pandas.merge(df1, df2) or df1.merge(df2). But for a number of common situations (keeping all rows of df1 and joining to an index in df2), you can save some typing by using df1.join(df2) instead.

Some notes on these issues from the documentation at http://pandas.pydata.org/pandas-docs/stable/merging.html#database-style-dataframe-joining-merging:

merge is a function in the pandas namespace, and it is also available as a DataFrame instance method, with the calling DataFrame being implicitly considered the left object in the join.

The related DataFrame.join method, uses merge internally for the index-on-index and index-on-column(s) joins, but joins on indexes by default rather than trying to join on common columns (the default behavior for merge). If you are joining on index, you may wish to use DataFrame.join to save yourself some typing.

...

These two function calls are completely equivalent:

left.join(right, on=key_or_keys)
pd.merge(left, right, left_on=key_or_keys, right_index=True, how='left', sort=False)

Count distinct values

You can do a distinct count as follows:

SELECT COUNT(DISTINCT column_name) FROM table_name;

EDIT:

Following your clarification and update to the question, I see now that it's quite a different question than we'd originally thought. "DISTINCT" has special meaning in SQL. If I understand correctly, you want something like this:

  • 2 customers had 1 pets
  • 3 customers had 2 pets
  • 1 customers had 3 pets

Now you're probably going to want to use a subquery:

select COUNT(*) column_name FROM (SELECT DISTINCT column_name);

Let me know if this isn't quite what you're looking for.

SQL Server Service not available in service list after installation of SQL Server Management Studio

You need to start the SQL Server manually. Press

windows + R

type

sqlservermanager12.msc

right click ->Start

Service configuration does not display SQL Server?

How to configure PHP to send e-mail?

Usually a good place to start when you run into problems is the manual. The page on configuring email explains that there's a big difference between the PHP mail command running on MSWindows and on every other operating system; it's a good idea when posting a question to provide relevant information on how that part of your system is configured and what operating system it is running on.

Your PHP is configured to talk to an SMTP server - the default for an MSWindows machine, but either you have no MTA installed or it's blocking connections. While for a commercial website running your own MTA robably comes quite high on the list of things to do, it is not a trivial exercise - you really need to know what you're doing to get one configured and running securely. It would make a lot more sense in your case to use a service configured and managed by someone else.

Since you'll be connecting to a remote MTA using a gmail address, then you should probably use Gmail's server; you will need SMTP authenticaton and probably SSL support - neither of which are supported by the mail() function in PHP. There's a simple example here using swiftmailer with gmail or here's an example using phpmailer

How does a hash table work?

This is how it works in my understanding:

Here's an example: picture the entire table as a series of buckets. Suppose you have an implementation with alpha-numeric hash-codes and have one bucket for each letter of the alphabet. This implementation puts each item whose hash code begins with a particular letter in the corresponding bucket.

Let's say you have 200 objects, but only 15 of them have hash codes that begin with the letter 'B.' The hash table would only need to look up and search through the 15 objects in the 'B' bucket, rather than all 200 objects.

As far as calculating the hash code, there is nothing magical about it. The goal is just to have different objects return different codes and for equal objects to return equal codes. You could write a class that always returns the same integer as a hash-code for all instances, but you would essentially destroy the usefulness of a hash-table, as it would just become one giant bucket.

C: printf a float value

printf("%9.6f", myFloat) specifies a format with 9 total characters: 2 digits before the dot, the dot itself, and six digits after the dot.

Operator overloading on class templates

This helped me with the exact same problem.

Solution:

  1. Forward declare the friend function before the definition of the class itself. For example:

       template<typename T> class MyClass;  // pre-declare the template class itself
       template<typename T> std::ostream& operator<< (std::ostream& o, const MyClass <T>& x);
    
  2. Declare your friend function in your class with "<>" appended to the function name.

       friend std::ostream& operator<< <> (std::ostream& o, const Foo<T>& x);
    

Clear an input field with Reactjs?

Declare value attribute for input tag (i.e value= {this.state.name}) and if you want to clear this input vale you have to use this.setState({name : ''})

PFB working code for your reference :

<script type="text/babel">
    var StateComponent = React.createClass({
        resetName : function(event){
            this.setState({
                name : ''
            });
        },
        render : function(){
            return (
                <div>
                    <input type="text" value= {this.state.name}/>
                    <button onClick={this.resetName}>Reset</button>
                </div>
            )
        }
    });
    ReactDOM.render(<StateComponent/>, document.getElementById('app'));
</script>

Custom domain for GitHub project pages

As of Aug 29, 2013, Github's documentation claim that:

Warning: Project pages subpaths like http://username.github.io/projectname will not be redirected to a project's custom domain.

How to configure socket connect timeout

This is like FlappySock's answer, but I added a callback to it because I didn't like the layout and how the Boolean was getting returned. In the comments of that answer from Nick Miller:

In my experience, if the end point can be reached, but there is no server on the endpoint able to receive the connection, then AsyncWaitHandle.WaitOne will be signaled, but the socket will remain unconnected

So to me, it seems relying on what is returned can be dangerous - I prefer to use socket.Connected. I set a nullable Boolean and update it in the callback function. I also found it doesn't always finish reporting the result before returning to the main function - I handle for that, too, and make it wait for the result using the timeout:

private static bool? areWeConnected = null;

private static bool checkSocket(string svrAddress, int port)
{
    IPEndPoint endPoint = new IPEndPoint(IPAddress.Parse(svrAddress), port);
    Socket socket = new Socket(endPoint.AddressFamily, SocketType.Stream, ProtocolType.Tcp);

    int timeout = 5000; // int.Parse(ConfigurationManager.AppSettings["socketTimeout"].ToString());
    int ctr = 0;
    IAsyncResult ar = socket.BeginConnect(endPoint, Connect_Callback, socket);
    ar.AsyncWaitHandle.WaitOne( timeout, true );

    // Sometimes it returns here as null before it's done checking the connection
    // No idea why, since .WaitOne() should block that, but it does happen
    while (areWeConnected == null && ctr < timeout)
    {
        Thread.Sleep(100);
        ctr += 100;
    } // Given 100ms between checks, it allows 50 checks 
      // for a 5 second timeout before we give up and return false, below

    if (areWeConnected == true)
    {
        return true;
    }
    else
    {
        return false;
    }
}

private static void Connect_Callback(IAsyncResult ar)
{
    areWeConnected = null;
    try
    {
        Socket socket = (Socket)ar.AsyncState;
        areWeConnected = socket.Connected;
        socket.EndConnect(ar);
    }
    catch (Exception ex)
    {
      areWeConnected = false;
      // log exception 
    }
}

Related: How to check if I'm connected?

Getting the difference between two sets

Just to put one example here (system is in existingState, and we want to find elements to remove (elements that are not in newState but are present in existingState) and elements to add (elements that are in newState but are not present in existingState) :

public class AddAndRemove {

  static Set<Integer> existingState = Set.of(1,2,3,4,5);
  static Set<Integer> newState = Set.of(0,5,2,11,3,99);

  public static void main(String[] args) {

    Set<Integer> add = new HashSet<>(newState);
    add.removeAll(existingState);

    System.out.println("Elements to add : " + add);

    Set<Integer> remove = new HashSet<>(existingState);
    remove.removeAll(newState);

    System.out.println("Elements to remove : " + remove);

  }
}

would output this as a result:

Elements to add : [0, 99, 11]
Elements to remove : [1, 4]

Can't connect to MySQL server error 111

111 means connection refused, which in turn means that your mysqld only listens to the localhost interface.

To alter it you may want to look at the bind-address value in the mysqld section of your my.cnf file.

Using the "start" command with parameters passed to the started program

None of these answers worked for me.

Instead, I had to use the Call command:

Call "\\Path To Program\Program.exe" <parameters>

I'm not sure this actually waits for completion... the C++ Redistributable I was installing went fast enough that it didn't matter

Get GPS location via a service in Android

Here is my solution

Step1 Register Serice in manifest

<receiver
    android:name=".MySMSBroadcastReceiver"
    android:exported="true">
    <intent-filter>
        <action android:name="com.google.android.gms.auth.api.phone.SMS_RETRIEVED" />
    </intent-filter>
</receiver>

Step2 Code Of Service

public class FusedLocationService extends Service {

    private String mLastUpdateTime = null;

    // bunch of location related apis
    private FusedLocationProviderClient mFusedLocationClient;
    private SettingsClient mSettingsClient;
    private LocationRequest mLocationRequest;
    private LocationSettingsRequest mLocationSettingsRequest;
    private LocationCallback mLocationCallback;
    private Location lastLocation;

    // location updates interval - 10sec
    private static final long UPDATE_INTERVAL_IN_MILLISECONDS = 5000;

    // fastest updates interval - 5 sec
    // location updates will be received if another app is requesting the locations
    // than your app can handle
    private static final long FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS = 500;
    private DatabaseReference locationRef;
    private int notificationBuilder = 0;
    private boolean isInitRef;

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Log.log("LOCATION GET DURATION", "start in service");
        init();
        return START_STICKY;
    }

    /**
     * Initilize Location Apis
     * Create Builder if Share location true
     */
    private void init() {
        mFusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
        mSettingsClient = LocationServices.getSettingsClient(this);
        mLocationCallback = new LocationCallback() {
            @Override
            public void onLocationResult(LocationResult locationResult) {
                super.onLocationResult(locationResult);
                receiveLocation(locationResult);
            }
        };

        mLocationRequest = new LocationRequest();
        mLocationRequest.setInterval(UPDATE_INTERVAL_IN_MILLISECONDS);
        mLocationRequest.setFastestInterval(FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS);
        mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);

        LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder();
        builder.addLocationRequest(mLocationRequest);
        mLocationSettingsRequest = builder.build();
        startLocationUpdates();
    }

    /**
     * Request Location Update
     */
    @SuppressLint("MissingPermission")
    private void startLocationUpdates() {
        mSettingsClient
                .checkLocationSettings(mLocationSettingsRequest)
                .addOnSuccessListener(locationSettingsResponse -> {
                    Log.log(TAG, "All location settings are satisfied. No MissingPermission");

                    //noinspection MissingPermission
                    mFusedLocationClient.requestLocationUpdates(mLocationRequest, mLocationCallback, Looper.myLooper());
                })
                .addOnFailureListener(e -> {
                    int statusCode = ((ApiException) e).getStatusCode();
                    switch (statusCode) {
                        case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
                            Log.loge("Location settings are not satisfied. Attempting to upgrade " + "location settings ");
                            break;
                        case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
                            Log.loge("Location settings are inadequate, and cannot be " + "fixed here. Fix in Settings.");
                    }
                });
    }

    /**
     * onLocationResult
     * on Receive Location  share to other activity and save if save true
     *
     * @param locationResult
     */
    private void receiveLocation(LocationResult locationResult) {
        lastLocation = locationResult.getLastLocation();

        LocationInstance.getInstance().changeState(lastLocation);

        saveLocation();
    }

    private void saveLocation() {
        String saveLocation = getsaveLocationStatus(this);

        if (saveLocation.equalsIgnoreCase("true") && notificationBuilder == 0) {
            notificationBuilder();
            notificationBuilder = 1;
        } else if (saveLocation.equalsIgnoreCase("false") && notificationBuilder == 1) {
            ((NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE)).cancel(1);
            notificationBuilder = 0;
        }

        Log.logd("receiveLocation : Share :- " + saveLocation + ", [Lat " + lastLocation.getLatitude() + ", Lng" + lastLocation.getLongitude() + "], Time :- " + mLastUpdateTime);

        if (saveLocation.equalsIgnoreCase("true") || getPreviousMin() < getCurrentMin()) {
            setLatLng(this, lastLocation);

            mLastUpdateTime = DateFormat.getTimeInstance().format(new Date());

            if (isOnline(this) && !getUserId(this).equalsIgnoreCase("")) {
                if (!isInitRef) {
                    locationRef = getFirebaseInstance().child(getUserId(this)).child("location");
                    isInitRef = true;
                }
                if (isInitRef) {
                    locationRef.setValue(new LocationModel(lastLocation.getLatitude(), lastLocation.getLongitude(), mLastUpdateTime));
                }
            }
        }
    }

    private int getPreviousMin() {
        int previous_min = 0;
        if (mLastUpdateTime != null) {
            String[] pretime = mLastUpdateTime.split(":");
            previous_min = Integer.parseInt(pretime[1].trim()) + 1;

            if (previous_min > 59) {
                previous_min = 0;
            }
        }
        return previous_min;
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        stopLocationUpdates();
    }

    /**
     * Remove Location Update
     */
    public void stopLocationUpdates() {
        mFusedLocationClient
                .removeLocationUpdates(mLocationCallback)
                .addOnCompleteListener(task -> Log.logd("stopLocationUpdates : "));
    }

    private void notificationBuilder() {
        if (Build.VERSION.SDK_INT >= 26) {
            String CHANNEL_ID = "my_channel_01";
            NotificationChannel channel = new NotificationChannel(CHANNEL_ID, "Channel human readable title",
                    NotificationManager.IMPORTANCE_DEFAULT);

            ((NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE)).createNotificationChannel(channel);

            Notification notification = new NotificationCompat.Builder(this, CHANNEL_ID)
                    .setContentTitle("")
                    .setContentText("").build();

            startForeground(1, notification);
        }
    }

    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }
}

Step 3

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.FOREGROUND_SERVICE" />

Step 4

implementation 'com.google.android.gms:play-services-location:16.0.0'

Print very long string completely in pandas dataframe

Another easier way to print the whole string is to call values on the dataframe.

df = pd.DataFrame({'one' : ['one', 'two', 
      'This is very long string very long string very long string veryvery long string']})

print(df.values)

The Output will be

[['one']
 ['two']
 ['This is very long string very long string very long string veryvery long string']]

RGB to hex and hex to RGB

One-line functional HEX to RGBA

Supports both short #fff and long #ffffff forms.
Supports alpha channel (opacity).
Does not care if hash specified or not, works in both cases.

function hexToRGBA(hex, opacity) {
    return 'rgba(' + (hex = hex.replace('#', '')).match(new RegExp('(.{' + hex.length/3 + '})', 'g')).map(function(l) { return parseInt(hex.length%2 ? l+l : l, 16) }).concat(isFinite(opacity) ? opacity : 1).join(',') + ')';
}

examples:

hexToRGBA('#fff')        ->  rgba(255,255,255,1)  
hexToRGBA('#ffffff')     ->  rgba(255,255,255,1)  
hexToRGBA('#fff', .2)    ->  rgba(255,255,255,0.2)  
hexToRGBA('#ffffff', .2) ->  rgba(255,255,255,0.2)  
hexToRGBA('fff', .2)     ->  rgba(255,255,255,0.2)  
hexToRGBA('ffffff', .2)  ->  rgba(255,255,255,0.2)

hexToRGBA('#ffffff', 0)  ->  rgba(255,255,255,0)
hexToRGBA('#ffffff', .5) ->  rgba(255,255,255,0.5)
hexToRGBA('#ffffff', 1)  ->  rgba(255,255,255,1)

Difference between webdriver.get() and webdriver.navigate()

To get a better understanding on it, one must see the architecture of Selenium WebDriver.

Just visit https://github.com/SeleniumHQ/selenium/wiki/JsonWireProtocol

and search for "Navigate to a new URL." text. You will see both methods GET and POST.

Hence the conclusion given below:

driver.get() method internally sends Get request to Selenium Server Standalone. Whereas driver.navigate() method sends Post request to Selenium Server Standalone.

Hope it helps

Most efficient way to concatenate strings in JavaScript?

You can also do string concat with template literals. I updated the other posters' JSPerf tests to include it.

for (var res = '', i = 0; i < data.length; i++) {
  res = `${res}${data[i]}`;
}

What is a 'NoneType' object?

It means you're trying to concatenate a string with something that is None.

None is the "null" of Python, and NoneType is its type.

This code will raise the same kind of error:

>>> bar = "something"
>>> foo = None
>>> print foo + bar
TypeError: cannot concatenate 'str' and 'NoneType' objects

Cannot set content-type to 'application/json' in jQuery.ajax

I can show you how I used it

  function GetDenierValue() {
        var denierid = $("#productDenierid").val() == '' ? 0 : $("#productDenierid").val();
        var param = { 'productDenierid': denierid };
        $.ajax({
            url: "/Admin/ProductComposition/GetDenierValue",
            dataType: "json",
            contentType: "application/json;charset=utf-8",
            type: "POST",
            data: JSON.stringify(param),
            success: function (msg) {
                if (msg != null) {
                    return msg.URL;
                }
            }
        });
    }

T-sql - determine if value is integer

Sometimes you don't get to design the database, you just have to work with what you are given. In my case it's a database located on a computer that I only have read access to which has been around since 2008.

I need to select from a column in a poorly designed database which is a varchar with numbers 1-100 but sometimes a random string. I used the following to get around it (although I wish I could have re designed the entire database).

SELECT A from TABLE where isnumeric(A)=1

Getting a 500 Internal Server Error on Laravel 5+ Ubuntu 14.04

Make sure storage folder with write previlege (chmod o+w), work for me like a charm.

Definition of a Balanced Tree

There's no difference between these two things. Think about it.

Let's take a simpler definition, "A positive number is even if it is zero or that number minus two is even." Does this say 8 is even if 6 is even? Or does this say 8 is even if 6, 4, 2, and 0 are even?

There's no difference. If it says 8 is even if 6 is even, it also says 6 is even if 4 is even. And thus it also says 4 is even if 2 is even. And thus it says 2 is even if 0 is even. So if it says 8 is even if 6 is even, it (indirectly) says 8 is even if 6, 4, 2, and 0 are even.

It's the same thing here. Any indirect sub-tree can be found by a chain of direct sub-trees. So even if it only applies directly to direct sub-trees, it still applies indirectly to all sub-trees (and thus all nodes).

Use superscripts in R axis labels

This is a quick example

plot(rnorm(30), xlab = expression(paste("4"^"th")))

How to hide output of subprocess in Python 2.7

Use subprocess.check_output (new in python 2.7). It will suppress stdout and raise an exception if the command fails. (It actually returns the contents of stdout, so you can use that later in your program if you want.) Example:

import subprocess
try:
    subprocess.check_output(['espeak', text])
except subprocess.CalledProcessError:
    # Do something

You can also suppress stderr with:

    subprocess.check_output(["espeak", text], stderr=subprocess.STDOUT)

For earlier than 2.7, use

import os
import subprocess
with open(os.devnull, 'w')  as FNULL:
    try:
        subprocess._check_call(['espeak', text], stdout=FNULL)
    except subprocess.CalledProcessError:
        # Do something

Here, you can suppress stderr with

        subprocess._check_call(['espeak', text], stdout=FNULL, stderr=FNULL)

How to delete/truncate tables from Hadoop-Hive?

You can use drop command to delete meta data and actual data from HDFS.

And just to delete data and keep the table structure, use truncate command.

For further help regarding hive ql, check language manual of hive.

Change background color of selected item on a ListView

If you want to have the item remain highlighted after you have clicked it, you need to manually set it as being selected in the onItemClick listener

Android ListView selected item stay highlighted:

myList.setOnItemClickListener(new OnItemClickListener() {
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {   
        view.setSelected(true); // <== Will cause the highlight to remain
        //... do more stuff                          
    }});

This assumes you have a state_selected item in your selector:

<?xml version="1.0" encoding="utf-8"?>
  <selector xmlns:android="http://schemas.android.com/apk/res/android">  
  <item android:state_enabled="true" android:state_pressed="true" android:drawable="@color/red" />
  <item android:state_enabled="true" android:state_focused="true" android:drawable="@color/red" />
  <item android:state_enabled="true" android:state_selected="true" android:drawable="@color/red" />
  <item android:drawable="@color/white" />
</selector>

Forward request headers from nginx proxy server

If you want to pass the variable to your proxy backend, you have to set it with the proxy module.

location / {
    proxy_pass                      http://example.com;
    proxy_set_header                Host example.com;
    proxy_set_header                HTTP_Country-Code $geoip_country_code;
    proxy_pass_request_headers      on;
}

And now it's passed to the proxy backend.

DatabaseError: current transaction is aborted, commands ignored until end of transaction block?

I think the pattern priestc mentions is more likely to be the usual cause of this issue when using PostgreSQL.

However I feel there are valid uses for the pattern and I don't think this issue should be a reason to always avoid it. For example:

try:
    profile = user.get_profile()
except ObjectDoesNotExist:
    profile = make_default_profile_for_user(user)

do_something_with_profile(profile)

If you do feel OK with this pattern, but want to avoid explicit transaction handling code all over the place then you might want to look into turning on autocommit mode (PostgreSQL 8.2+): https://docs.djangoproject.com/en/dev/ref/databases/#autocommit-mode

DATABASES['default'] = {
    #.. you usual options...
    'OPTIONS': {
        'autocommit': True,
    }
}

I am unsure if there are important performance considerations (or of any other type).

Browse for a directory in C#

or even more better, you can put this code in a class file

using System;
using System.IO;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Windows.Forms;

internal class OpenFolderDialog : IDisposable {

    /// <summary>
    /// Gets/sets folder in which dialog will be open.
    /// </summary>
    public string InitialFolder { get; set; }

    /// <summary>
    /// Gets/sets directory in which dialog will be open if there is no recent directory available.
    /// </summary>
    public string DefaultFolder { get; set; }

    /// <summary>
    /// Gets selected folder.
    /// </summary>
    public string Folder { get; private set; }


    internal DialogResult ShowDialog(IWin32Window owner) {
        if (Environment.OSVersion.Version.Major >= 6) {
            return ShowVistaDialog(owner);
        } else {
            return ShowLegacyDialog(owner);
        }
    }

    private DialogResult ShowVistaDialog(IWin32Window owner) {
        var frm = (NativeMethods.IFileDialog)(new NativeMethods.FileOpenDialogRCW());
        uint options;
        frm.GetOptions(out options);
        options |= NativeMethods.FOS_PICKFOLDERS | NativeMethods.FOS_FORCEFILESYSTEM | NativeMethods.FOS_NOVALIDATE | NativeMethods.FOS_NOTESTFILECREATE | NativeMethods.FOS_DONTADDTORECENT;
        frm.SetOptions(options);
        if (this.InitialFolder != null) {
            NativeMethods.IShellItem directoryShellItem;
            var riid = new Guid("43826D1E-E718-42EE-BC55-A1E261C37BFE"); //IShellItem
            if (NativeMethods.SHCreateItemFromParsingName(this.InitialFolder, IntPtr.Zero, ref riid, out directoryShellItem) == NativeMethods.S_OK) {
                frm.SetFolder(directoryShellItem);
            }
        }
        if (this.DefaultFolder != null) {
            NativeMethods.IShellItem directoryShellItem;
            var riid = new Guid("43826D1E-E718-42EE-BC55-A1E261C37BFE"); //IShellItem
            if (NativeMethods.SHCreateItemFromParsingName(this.DefaultFolder, IntPtr.Zero, ref riid, out directoryShellItem) == NativeMethods.S_OK) {
                frm.SetDefaultFolder(directoryShellItem);
            }
        }

        if (frm.Show(owner.Handle) == NativeMethods.S_OK) {
            NativeMethods.IShellItem shellItem;
            if (frm.GetResult(out shellItem) == NativeMethods.S_OK) {
                IntPtr pszString;
                if (shellItem.GetDisplayName(NativeMethods.SIGDN_FILESYSPATH, out pszString) == NativeMethods.S_OK) {
                    if (pszString != IntPtr.Zero) {
                        try {
                            this.Folder = Marshal.PtrToStringAuto(pszString);
                            return DialogResult.OK;
                        } finally {
                            Marshal.FreeCoTaskMem(pszString);
                        }
                    }
                }
            }
        }
        return DialogResult.Cancel;
    }

    private DialogResult ShowLegacyDialog(IWin32Window owner) {
        using (var frm = new SaveFileDialog()) {
            frm.CheckFileExists = false;
            frm.CheckPathExists = true;
            frm.CreatePrompt = false;
            frm.Filter = "|" + Guid.Empty.ToString();
            frm.FileName = "any";
            if (this.InitialFolder != null) { frm.InitialDirectory = this.InitialFolder; }
            frm.OverwritePrompt = false;
            frm.Title = "Select Folder";
            frm.ValidateNames = false;
            if (frm.ShowDialog(owner) == DialogResult.OK) {
                this.Folder = Path.GetDirectoryName(frm.FileName);
                return DialogResult.OK;
            } else {
                return DialogResult.Cancel;
            }
        }
    }


    public void Dispose() { } //just to have possibility of Using statement.

}

internal static class NativeMethods {

    #region Constants

    public const uint FOS_PICKFOLDERS = 0x00000020;
    public const uint FOS_FORCEFILESYSTEM = 0x00000040;
    public const uint FOS_NOVALIDATE = 0x00000100;
    public const uint FOS_NOTESTFILECREATE = 0x00010000;
    public const uint FOS_DONTADDTORECENT = 0x02000000;

    public const uint S_OK = 0x0000;

    public const uint SIGDN_FILESYSPATH = 0x80058000;

    #endregion


    #region COM

    [ComImport, ClassInterface(ClassInterfaceType.None), TypeLibType(TypeLibTypeFlags.FCanCreate), Guid("DC1C5A9C-E88A-4DDE-A5A1-60F82A20AEF7")]
    internal class FileOpenDialogRCW { }


    [ComImport(), Guid("42F85136-DB7E-439C-85F1-E4075D135FC8"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
    internal interface IFileDialog {
        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        [PreserveSig()]
        uint Show([In, Optional] IntPtr hwndOwner); //IModalWindow 


        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint SetFileTypes([In] uint cFileTypes, [In, MarshalAs(UnmanagedType.LPArray)] IntPtr rgFilterSpec);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint SetFileTypeIndex([In] uint iFileType);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint GetFileTypeIndex(out uint piFileType);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint Advise([In, MarshalAs(UnmanagedType.Interface)] IntPtr pfde, out uint pdwCookie);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint Unadvise([In] uint dwCookie);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint SetOptions([In] uint fos);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint GetOptions(out uint fos);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        void SetDefaultFolder([In, MarshalAs(UnmanagedType.Interface)] IShellItem psi);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint SetFolder([In, MarshalAs(UnmanagedType.Interface)] IShellItem psi);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint GetFolder([MarshalAs(UnmanagedType.Interface)] out IShellItem ppsi);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint GetCurrentSelection([MarshalAs(UnmanagedType.Interface)] out IShellItem ppsi);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint SetFileName([In, MarshalAs(UnmanagedType.LPWStr)] string pszName);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint GetFileName([MarshalAs(UnmanagedType.LPWStr)] out string pszName);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint SetTitle([In, MarshalAs(UnmanagedType.LPWStr)] string pszTitle);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint SetOkButtonLabel([In, MarshalAs(UnmanagedType.LPWStr)] string pszText);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint SetFileNameLabel([In, MarshalAs(UnmanagedType.LPWStr)] string pszLabel);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint GetResult([MarshalAs(UnmanagedType.Interface)] out IShellItem ppsi);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint AddPlace([In, MarshalAs(UnmanagedType.Interface)] IShellItem psi, uint fdap);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint SetDefaultExtension([In, MarshalAs(UnmanagedType.LPWStr)] string pszDefaultExtension);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint Close([MarshalAs(UnmanagedType.Error)] uint hr);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint SetClientGuid([In] ref Guid guid);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint ClearClientData();

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint SetFilter([MarshalAs(UnmanagedType.Interface)] IntPtr pFilter);
    }


    [ComImport, Guid("43826D1E-E718-42EE-BC55-A1E261C37BFE"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
    internal interface IShellItem {
        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint BindToHandler([In] IntPtr pbc, [In] ref Guid rbhid, [In] ref Guid riid, [Out, MarshalAs(UnmanagedType.Interface)] out IntPtr ppvOut);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint GetParent([MarshalAs(UnmanagedType.Interface)] out IShellItem ppsi);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint GetDisplayName([In] uint sigdnName, out IntPtr ppszName);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint GetAttributes([In] uint sfgaoMask, out uint psfgaoAttribs);

        [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
        uint Compare([In, MarshalAs(UnmanagedType.Interface)] IShellItem psi, [In] uint hint, out int piOrder);
    }

    #endregion


    [DllImport("shell32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
    internal static extern int SHCreateItemFromParsingName([MarshalAs(UnmanagedType.LPWStr)] string pszPath, IntPtr pbc, ref Guid riid, [MarshalAs(UnmanagedType.Interface)] out IShellItem ppv);

}

And use it like this

using (var frm = new OpenFolderDialog()) {
                if (frm.ShowDialog(this)== DialogResult.OK) {
                    MessageBox.Show(this, frm.Folder);
                }
            }

Why can't I find SQL Server Management Studio after installation?

It appears that SQL Server 2008 R2 can be downloaded with or without the management tools. I honestly have NO IDEA why someone would not want the management tools. But either way, the options are here:

http://www.microsoft.com/sqlserver/en/us/editions/express.aspx

and the one for 64 bit WITH the management tools (management studio) is here:

http://www.microsoft.com/sqlserver/en/us/editions/express.aspx

From the first link I presented, the 3rd and 4th include the management studio for 32 and 64 bit respectively.

How to display JavaScript variables in a HTML page without document.write

You could use jquery to get hold of the html element that you want to load the value with.

Say for instance if your page looks something like this,

<div id="FirstDiv">
  <div id="SecondDiv">
     ...
  </div>
 </div>

And if your javascript (I hope) looks something as simple as this,

function somefunction(){
  var somevalue = "Data to be inserted";
  $("#SecondDiv").text(somevalue);
}

I hope this is what you were looking for.

Class vs. static method in JavaScript

You can achieve it as below:

function Foo() {};

Foo.talk = function() { alert('I am talking.'); };

You can now invoke "talk" function as below:

Foo.talk();

You can do this because in JavaScript, functions are objects as well.

How do I get the resource id of an image if I know its name?

You can use this function to get a Resource ID:

public static int getResourseId(Context context, String pVariableName, String pResourcename, String pPackageName) throws RuntimeException {
    try {
        return context.getResources().getIdentifier(pVariableName, pResourcename, pPackageName);
    } catch (Exception e) {
        throw new RuntimeException("Error getting Resource ID.", e)
    } 
}


So if you want to get a Drawable Resource ID, you can call the method like this:

getResourseId(MyActivity.this, "myIcon", "drawable", getPackageName());

(or from a fragment):

getResourseId(getActivity(), "myIcon", "drawable", getActivity().getPackageName());


For a String Resource ID you can call it like this:

getResourseId(getActivity(), "myAppName", "string", getActivity().getPackageName());

etc...


Careful: It throws a RuntimeException if it fails to find the Resource ID. Be sure to recover properly in production.

Read this

How to clear an EditText on click?

I'm not sure if you are after this, but try this XML:

android:hint="Enter Name"

It displays that text when the input field is empty, selected or unselected.

Or if you want it to do exactly as you described, assign a onClickListener on the editText and set it empty with setText().

SQL: How do I SELECT only the rows with a unique value on certain column?

SELECT DISTINCT Contract, Activity
FROM Contract WHERE Contract IN (
SELECT Contract 
FROM Contract
GROUP BY Contract
HAVING COUNT( DISTINCT Activity ) = 1 )

Read input numbers separated by spaces

I would recommend reading in the line into a string, then splitting it based on the spaces. For this, you can use the getline(...) function. The trick is having a dynamic sized data structure to hold the strings once it's split. Probably the easiest to use would be a vector.

#include <string>
#include <vector>
...
  string rawInput;
  vector<String> numbers;
  while( getline( cin, rawInput, ' ' ) )
  {
    numbers.push_back(rawInput);
  }

So say the input looks like this:

Enter a number, or numbers separated by a space, between 1 and 1000.
10 5 20 1 200 7

You will now have a vector, numbers, that contains the elements: {"10","5","20","1","200","7"}.

Note that these are still strings, so not useful in arithmetic. To convert them to integers, we use a combination of the STL function, atoi(...), and because atoi requires a c-string instead of a c++ style string, we use the string class' c_str() member function.

while(!numbers.empty())
{
  string temp = numbers.pop_back();//removes the last element from the string
  num = atoi( temp.c_str() ); //re-used your 'num' variable from your code

  ...//do stuff
}

Now there's some problems with this code. Yes, it runs, but it is kind of clunky, and it puts the numbers out in reverse order. Lets re-write it so that it is a little more compact:

#include <string>
...
string rawInput;
cout << "Enter a number, or numbers separated by a space, between 1 and 1000." << endl;
while( getline( cin, rawInput, ' ') )
{
  num = atoi( rawInput.c_str() );
  ...//do your stuff
}

There's still lots of room for improvement with error handling (right now if you enter a non-number the program will crash), and there's infinitely more ways to actually handle the input to get it in a usable number form (the joys of programming!), but that should give you a comprehensive start. :)

Note: I had the reference pages as links, but I cannot post more than two since I have less than 15 posts :/

Edit: I was a little bit wrong about the atoi behavior; I confused it with Java's string->Integer conversions which throw a Not-A-Number exception when given a string that isn't a number, and then crashes the program if the exception isn't handled. atoi(), on the other hand, returns 0, which is not as helpful because what if 0 is the number they entered? Let's make use of the isdigit(...) function. An important thing to note here is that c++ style strings can be accessed like an array, meaning rawInput[0] is the first character in the string all the way up to rawInput[length - 1].

#include <string>
#include <ctype.h>
...
string rawInput;
cout << "Enter a number, or numbers separated by a space, between 1 and 1000." << endl;
while( getline( cin, rawInput, ' ') )
{
  bool isNum = true;
  for(int i = 0; i < rawInput.length() && isNum; ++i)
  {
    isNum = isdigit( rawInput[i]);
  }

  if(isNum)
  {
    num = atoi( rawInput.c_str() );
    ...//do your stuff
  }
  else
    cout << rawInput << " is not a number!" << endl;
}

The boolean (true/false or 1/0 respectively) is used as a flag for the for-loop, which steps through each character in the string and checks to see if it is a 0-9 digit. If any character in the string is not a digit, the loop will break during it's next execution when it gets to the condition "&& isNum" (assuming you've covered loops already). Then after the loop, isNum is used to determine whether to do your stuff, or to print the error message.

What is the difference between signed and unsigned variables?

Signed variables use one bit to flag whether they are positive or negative. Unsigned variables don't have this bit, so they can store larger numbers in the same space, but only nonnegative numbers, e.g. 0 and higher.

For more: Unsigned and Signed Integers

Cannot make file java.io.IOException: No such file or directory

Be careful with permissions, it is problably you don't have some of them. You can see it in settings -> apps -> name of the application -> permissions -> active if not.

Permissions app

Prevent browser caching of AJAX call result

The real question is why you need this to not be cached. If it should not be cached because it changes all the time, the server should specify to not cache the resource. If it just changes sometimes (because one of the resources it depends on can change), and if the client code has a way of knowing about it, it can append a dummy parameter to the url that is computed from some hash or last modified date of those resources (that's what we do in Microsoft Ajax script resources so they can be cached forever but new versions can still be served as they appear). If the client can't know of changes, the correct way should be for the server to handle HEAD requests properly and tell the client whether to use the cached version or not. Seems to me like appending a random parameter or telling from the client to never cache is wrong because cacheability is a property of the server resource, and so should be decided server-side. Another question to ask oneself is should this resource really be served through GET or should it go through POST? That is a question of semantics, but it also has security implications (there are attacks that work only if the server allows for GET). POST will not get cached.

How to convert string to boolean php

Other answers are over complicating things. This question is simply logic question. Just get your statement right.

$boolString = 'false';
$result = 'true' === $boolString;

Now your answer will be either

  • false, if the string was 'false',
  • or true, if your string was 'true'.

I have to note that filter_var( $boolString, FILTER_VALIDATE_BOOLEAN ); still will be a better option if you need to have strings like on/yes/1 as alias for true.

How to change text color of cmd with windows batch script every 1 second

@echo off
set NUM=0 1 2 3 4 5 6 7 8 9 A B C D E F 31 32 33 34 35 36 37 41 42 43 44 45 46 90 91 92 93 94 95 96 97 100 101 102 103 104 105 106 107 
for %%x in (%NUM%) do ( 
    for %%y in (%NUM%) do (
        color %%x%%y
cls
echo Himel Sarkar
        timeout 1 >nul
    )
)

pause

UnsatisfiedDependencyException: Error creating bean with name

Add @Component annotation just above the component definition

warning: assignment makes integer from pointer without a cast

The warning comes from the fact that you're dereferencing src in the assignment. The expression *src has type char, which is an integral type. The expression "anotherstring" has type char [14], which in this particular context is implicitly converted to type char *, and its value is the address of the first character in the array. So, you wind up trying to assign a pointer value to an integral type, hence the warning. Drop the * from *src, and it should work as expected:

src = "anotherstring";

since the type of src is char *.

Create a basic matrix in C (input by user !)

need a

for(i=0;i<2;i++)
{
  for(j=0;j<2;j++)
  {
     printf("%d",mat[i][j]);
  }
  printf("\n");
}

console.log showing contents of array object

Seems like Firebug or whatever Debugger you are using, is not initialized properly. Are you sure Firebug is fully initialized when you try to access the console.log()-method? Check the Console-Tab (if it's set to activated).

Another possibility could be, that you overwrite the console-Object yourself anywhere in the code.

converting Java bitmap to byte array

Here is bitmap extension .convertToByteArray wrote in Kotlin.

/**
 * Convert bitmap to byte array using ByteBuffer.
 */
fun Bitmap.convertToByteArray(): ByteArray {
    //minimum number of bytes that can be used to store this bitmap's pixels
    val size = this.byteCount

    //allocate new instances which will hold bitmap
    val buffer = ByteBuffer.allocate(size)
    val bytes = ByteArray(size)

    //copy the bitmap's pixels into the specified buffer
    this.copyPixelsToBuffer(buffer)

    //rewinds buffer (buffer position is set to zero and the mark is discarded)
    buffer.rewind()

    //transfer bytes from buffer into the given destination array
    buffer.get(bytes)

    //return bitmap's pixels
    return bytes
}

Header and footer in CodeIgniter

I had this problem where I want a controller to end with a message such as 'Thanks for that form' and generic 'not found etc'. I do this under views->message->message_v.php

<?php
    $title = "Message";
    $this->load->view('templates/message_header', array("title" => $title));
?>
<h1>Message</h1>
<?php echo $msg_text; ?>
<h2>Thanks</h2>
<?php $this->load->view('templates/message_footer'); ?>

which allows me to change message rendering site wide in that single file for any thing that calls

$this->load->view("message/message_v", $data);

Bootstrap 4 datapicker.js not included

Maybe you want to try this: https://bootstrap-datepicker.readthedocs.org/en/latest/index.html

It's a flexible datepicker widget in the Bootstrap style.

What is the maximum number of characters that nvarchar(MAX) will hold?

From char and varchar (Transact-SQL)

varchar [ ( n | max ) ]

Variable-length, non-Unicode character data. n can be a value from 1 through 8,000. max indicates that the maximum storage size is 2^31-1 bytes. The storage size is the actual length of data entered + 2 bytes. The data entered can be 0 characters in length. The ISO synonyms for varchar are char varying or character varying.

PowerShell says "execution of scripts is disabled on this system."

RemoteSigned: all scripts you created yourself will be run, and all scripts downloaded from the Internet will need to be signed by a trusted publisher.

OK, change the policy by simply typing:

Set-ExecutionPolicy RemoteSigned

Unable to negotiate with XX.XXX.XX.XX: no matching host key type found. Their offer: ssh-dss

You can also add -oHostKeyAlgorithms=+ssh-dss in your ssh line:

ssh -oHostKeyAlgorithms=+ssh-dss user@host

Why I've got no crontab entry on OS X when using vim?

Other option is not to use crontab -e at all. Instead I used:

(crontab -l && echo "1 1  * * *  /path/to/my/script.sh") | crontab -

Notice that whatever you print before | crontab - will replace the entire crontab file, so use crontab -l && echo "<your new schedule>" to get the previous content and the new schedule.

Oracle find a constraint

maybe this can help..

SELECT constraint_name, constraint_type, column_name
from user_constraints natural join user_cons_columns
where table_name = "my_table_name";

How to validate an email address using a regular expression?

I never bother creating with my own regular expression, because chances are that someone else has already come up with a better version. I always use regexlib to find one to my liking.

PHP regular expression - filter number only

This is the right answer

preg_match("/^[0-9]+$/", $yourstr);

This function return TRUE(1) if it matches or FALSE(0) if it doesn't

Quick Explanation :

'^' : means that it should begin with the following ( in our case is a range of digital numbers [0-9] ) ( to avoid cases like ("abdjdf125") )

'+' : means there should be at least one digit

'$' : means after our pattern the string should end ( to avoid cases like ("125abdjdf") )

Where is database .bak file saved from SQL Server Management Studio?

Set registry item for your server instance. For example:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL.2\MSSQLServer\BackupDirectory

How can I convert string to double in C++?

One of the most elegant solution to this problem is to use boost::lexical_cast as @Evgeny Lazin mentioned.

Referencing value in a closed Excel workbook using INDIRECT?

OK,

Here's a dinosaur method for you on Office 2010.

Write the full address you want using concatenate (the "&" method of combining text).

Do this for all the addresses you need. It should look like:

="="&"'\FULL NETWORK ADDRESS including [Spreadsheet Name]"&W3&"'!$w4"

The W3 is a dynamic reference to what sheet I am using, the W4 is the cell I want to get from the sheet.

Once you have this, start up a macro recording session. Copy the cell and paste it into another. I pasted it into a merged cell and it gave me the classic "Same size" error. But one thing it did was paste the resulting text from my concatenate (including that extra "=").

Copy over however many you did this for. Then, go into each pasted cell, select he text and just hit enter. It updates it to an active direct reference.

Once you have finished, put the cursor somewhere nice and stop the macro. Assign it to a button and you are done.

It is a bit of a PITA to do this the first time, but once you have done it, you have just made the square peg fit that daamned round hole.

Is there a rule-of-thumb for how to divide a dataset into training and validation sets?

Suppose you have less data, I suggest to try 70%, 80% and 90% and test which is giving better result. In case of 90% there are chances that for 10% test you get poor accuracy.

Extension methods must be defined in a non-generic static class

Try changing it to static class and back. That might resolve visual studio complaining when it's a false positive.

What does 'useLegacyV2RuntimeActivationPolicy' do in the .NET 4 config?

Here's an explanation I wrote recently to help with the void of information on this attribute. http://www.marklio.com/marklio/PermaLink,guid,ecc34c3c-be44-4422-86b7-900900e451f9.aspx (Internet Archive Wayback Machine link)

To quote the most relevant bits:

[Installing .NET] v4 is “non-impactful”. It should not change the behavior of existing components when installed.

The useLegacyV2RuntimeActivationPolicy attribute basically lets you say, “I have some dependencies on the legacy shim APIs. Please make them work the way they used to with respect to the chosen runtime.”

Why don’t we make this the default behavior? You might argue that this behavior is more compatible, and makes porting code from previous versions much easier. If you’ll recall, this can’t be the default behavior because it would make installation of v4 impactful, which can break existing apps installed on your machine.

The full post explains this in more detail. At RTM, the MSDN docs on this should be better.

How to deserialize xml to object

Your classes should look like this

[XmlRoot("StepList")]
public class StepList
{
    [XmlElement("Step")]
    public List<Step> Steps { get; set; }
}

public class Step
{
    [XmlElement("Name")]
    public string Name { get; set; }
    [XmlElement("Desc")]
    public string Desc { get; set; }
}

Here is my testcode.

string testData = @"<StepList>
                        <Step>
                            <Name>Name1</Name>
                            <Desc>Desc1</Desc>
                        </Step>
                        <Step>
                            <Name>Name2</Name>
                            <Desc>Desc2</Desc>
                        </Step>
                    </StepList>";

XmlSerializer serializer = new XmlSerializer(typeof(StepList));
using (TextReader reader = new StringReader(testData))
{
    StepList result = (StepList) serializer.Deserialize(reader);
}

If you want to read a text file you should load the file into a FileStream and deserialize this.

using (FileStream fileStream = new FileStream("<PathToYourFile>", FileMode.Open)) 
{
    StepList result = (StepList) serializer.Deserialize(fileStream);
}

Django: OperationalError No Such Table

This comment on this page worked for me and a few others. It deserves its own answer:

python manage.py migrate --run-syncdb

How to negate 'isblank' function

I suggest:

=not(isblank(A1))  

which returns TRUE if A1 is populated and FALSE otherwise. Which compares with:

=isblank(A1)  

which returns TRUE if A1 is empty and otherwise FALSE.

Uncaught TypeError: Cannot assign to read only property

When you use Object.defineProperties, by default writable is set to false, so _year and edition are actually read only properties.

Explicitly set them to writable: true:

_year: {
    value: 2004,
    writable: true
},

edition: {
    value: 1,
    writable: true
},

Check out MDN for this method.

writable
true if and only if the value associated with the property may be changed with an assignment operator.
Defaults to false.

onclick event pass <li> id or value

I prefer to use the HTML5 data API, check this documentation:

A example

_x000D_
_x000D_
$('#some-list li').click(function() {_x000D_
  var textLoaded = 'Loading element with id='_x000D_
         + $(this).data('id');_x000D_
   $('#loading-content').text(textLoaded);_x000D_
});
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
<ul id='some-list'>_x000D_
  <li data-id='1'>One </li>_x000D_
  <li data-id='2'>Two </li>_x000D_
  <!-- ... more li -->_x000D_
  <li data-id='n'>Other</li>_x000D_
</ul>_x000D_
_x000D_
<h1 id='loading-content'></h1>
_x000D_
_x000D_
_x000D_

Setting the selected attribute on a select list using jQuery

<select id="cars">
<option value='volvo'>volvo</option>
<option value='bmw'>bmw</option>
<option value='fiat'>fiat</option>
</select>

var make = "fiat";

$("#cars option[value='" + make + "']").attr("selected","selected");

How do I format a number with commas in T-SQL?

For SQL Server before 2012 which does not include the FORMAT function, create this function:

CREATE FUNCTION FormatCurrency(@value numeric(30,2))
    RETURNS varchar(50)
    AS
    BEGIN
        DECLARE @NumAsChar VARCHAR(50)
        SET @NumAsChar = '$' + CONVERT(varchar(50), CAST(@Value AS money),1)
        RETURN @NumAsChar
    END 

select dbo.FormatCurrency(12345678) returns $12,345,678.00

Drop the $ if you just want commas.

Swap two items in List<T>

If order matters, you should keep a property on the "T" objects in your list that denotes sequence. In order to swap them, just swap the value of that property, and then use that in the .Sort(comparison with sequence property)

List of All Locales and Their Short Codes?

I spend a whole day organizing this information for my company since we are building a multi-lingual platform. If you find any issue, missing language, or incorrect charset please edit the list so it will be more useful in the future. Here is the complete list of all the language locales, names, and charsets.

For PHP array here is the link https://github.com/jerryurenaa/language-list/blob/main/language-list-array.php

for JSON here is the link https://github.com/jerryurenaa/language-list/blob/main/language-list-json.json

How to use if - else structure in a batch file?

IF...ELSE IF constructs work very well in batch files, in particular when you use only one conditional expression on each IF line:

IF %F%==1 (
    ::copying the file c to d
    copy "%sourceFile%1" "%destinationFile1%"
) ELSE IF %F%==0 (
    ::moving the file e to f
    move "%sourceFile2%" "%destinationFile2%" )

In your example you use IF...AND...IF type construct, where 2 conditions must be met simultaneously. In this case you can still use IF...ELSE IF construct, but with extra parentheses to avoid uncertainty for the next ELSE condition:

IF %F%==1 (IF %C%==1 (
    ::copying the file c to d
    copy "%sourceFile1%" "%destinationFile1%" )
) ELSE IF %F%==1 (IF %C%==0 (
    ::moving the file e to f
    move "%sourceFile2%" "%destinationFile2%"))

The above construct is equivalent to:

IF %F%==1 (
    IF %C%==1 (
    ::copying the file c to d
    copy "%sourceFile1%" "%destinationFile1%"
    ) ELSE IF %C%==0 (
    ::moving the file e to f
    move "%sourceFile2%" "%destinationFile2%"))

Processing sequence of batch commands depends on CMD.exe parsing order. Just make sure your construct follows that logical order, and as a rule it will work. If your batch script is processed by Cmd.exe without errors, it means this is the correct (i.e. supported by your OS Cmd.exe version) construct, even if someone said otherwise.

When must we use NVARCHAR/NCHAR instead of VARCHAR/CHAR in SQL Server?

The real reason you want to use NVARCHAR is when you have different languages in the same column, you need to address the columns in T-SQL without decoding, you want to be able to see the data "natively" in SSMS, or you want to standardize on Unicode.

If you treat the database as dumb storage, it is perfectly possible to store wide strings and different (even variable-length) encodings in VARCHAR (for instance UTF-8). The problem comes when you are attempting to encode and decode, especially if the code page is different for different rows. It also means that the SQL Server will not be able to deal with the data easily for purposes of querying within T-SQL on (potentially variably) encoded columns.

Using NVARCHAR avoids all this.

I would recommend NVARCHAR for any column which will have user-entered data in it which is relatively unconstrained.

I would recommend VARCHAR for any column which is a natural key (like a vehicle license plate, SSN, serial number, service tag, order number, airport callsign, etc) which is typically defined and constrained by a standard or legislation or convention. Also VARCHAR for user-entered, and very constrained (like a phone number) or a code (ACTIVE/CLOSED, Y/N, M/F, M/S/D/W, etc). There is absolutely no reason to use NVARCHAR for those.

So for a simple rule:

VARCHAR when guaranteed to be constrained NVARCHAR otherwise

Oracle SQL escape character (for a '&')

the & is the default value for DEFINE, which allows you to use substitution variables. I like to turn it off using

SET DEFINE OFF

then you won't have to worry about escaping or CHR(38).

How do I use extern to share variables between source files?

First off, the extern keyword is not used for defining a variable; rather it is used for declaring a variable. I can say extern is a storage class, not a data type.

extern is used to let other C files or external components know this variable is already defined somewhere. Example: if you are building a library, no need to define global variable mandatorily somewhere in library itself. The library will be compiled directly, but while linking the file, it checks for the definition.

PHPUnit assert that an exception was thrown?

/**
 * @expectedException Exception
 * @expectedExceptionMessage Amount has to be bigger then 0!
 */
public function testDepositNegative()
{
    $this->account->deposit(-7);
}

Be very carefull about "/**", notice the double "*". Writing only "**"(asterix) will fail your code. Also make sure your using last version of phpUnit. In some earlier versions of phpunit @expectedException Exception is not supported. I had 4.0 and it didn't work for me, I had to update to 5.5 https://coderwall.com/p/mklvdw/install-phpunit-with-composer to update with composer.

Is it possible only to declare a variable without assigning any value in Python?

It is a good question and unfortunately bad answers as var = None is already assigning a value, and if your script runs multiple times it is overwritten with None every time.

It is not the same as defining without assignment. I am still trying to figure out how to bypass this issue.

How to drop rows of Pandas DataFrame whose value in a certain column is NaN

Simplest of all solutions:

filtered_df = df[df['EPS'].notnull()]

The above solution is way better than using np.isfinite()

AmazonS3 putObject with InputStream length example

adding log4j-1.2.12.jar file has resolved the issue for me

Remove all special characters from a string

Update

The solution below has a "SEO friendlier" version:

function hyphenize($string) {
    $dict = array(
        "I'm"      => "I am",
        "thier"    => "their",
        // Add your own replacements here
    );
    return strtolower(
        preg_replace(
          array( '#[\\s-]+#', '#[^A-Za-z0-9. -]+#' ),
          array( '-', '' ),
          // the full cleanString() can be downloaded from http://www.unexpectedit.com/php/php-clean-string-of-utf8-chars-convert-to-similar-ascii-char
          cleanString(
              str_replace( // preg_replace can be used to support more complicated replacements
                  array_keys($dict),
                  array_values($dict),
                  urldecode($string)
              )
          )
        )
    );
}

function cleanString($text) {
    $utf8 = array(
        '/[áàâãªä]/u'   =>   'a',
        '/[ÁÀÂÃÄ]/u'    =>   'A',
        '/[ÍÌÎÏ]/u'     =>   'I',
        '/[íìîï]/u'     =>   'i',
        '/[éèêë]/u'     =>   'e',
        '/[ÉÈÊË]/u'     =>   'E',
        '/[óòôõºö]/u'   =>   'o',
        '/[ÓÒÔÕÖ]/u'    =>   'O',
        '/[úùûü]/u'     =>   'u',
        '/[ÚÙÛÜ]/u'     =>   'U',
        '/ç/'           =>   'c',
        '/Ç/'           =>   'C',
        '/ñ/'           =>   'n',
        '/Ñ/'           =>   'N',
        '/–/'           =>   '-', // UTF-8 hyphen to "normal" hyphen
        '/[’‘‹›‚]/u'    =>   ' ', // Literally a single quote
        '/[“”«»„]/u'    =>   ' ', // Double quote
        '/ /'           =>   ' ', // nonbreaking space (equiv. to 0x160)
    );
    return preg_replace(array_keys($utf8), array_values($utf8), $text);
}

The rationale for the above functions (which I find way inefficient - the one below is better) is that a service that shall not be named apparently ran spelling checks and keyword recognition on the URLs.

After losing a long time on a customer's paranoias, I found out they were not imagining things after all -- their SEO experts [I am definitely not one] reported that, say, converting "Viaggi Economy Perù" to viaggi-economy-peru "behaved better" than viaggi-economy-per (the previous "cleaning" removed UTF8 characters; Bogotà became bogot, Medellìn became medelln and so on).

There were also some common misspellings that seemed to influence the results, and the only explanation that made sense to me is that our URL were being unpacked, the words singled out, and used to drive God knows what ranking algorithms. And those algorithms apparently had been fed with UTF8-cleaned strings, so that "Perù" became "Peru" instead of "Per". "Per" did not match and sort of took it in the neck.

In order to both keep UTF8 characters and replace some misspellings, the faster function below became the more accurate (?) function above. $dict needs to be hand tailored, of course.

Previous answer

A simple approach:

// Remove all characters except A-Z, a-z, 0-9, dots, hyphens and spaces
// Note that the hyphen must go last not to be confused with a range (A-Z)
// and the dot, NOT being special (I know. My life was a lie), is NOT escaped

$str = preg_replace('/[^A-Za-z0-9. -]/', '', $str);

// Replace sequences of spaces with hyphen
$str = preg_replace('/  */', '-', $str);

// The above means "a space, followed by a space repeated zero or more times"
// (should be equivalent to / +/)

// You may also want to try this alternative:
$str = preg_replace('/\\s+/', '-', $str);

// where \s+ means "zero or more whitespaces" (a space is not necessarily the
// same as a whitespace) just to be sure and include everything

Note that you might have to first urldecode() the URL, since %20 and + both are actually spaces - I mean, if you have "Never%20gonna%20give%20you%20up" you want it to become Never-gonna-give-you-up, not Never20gonna20give20you20up . You might not need it, but I thought I'd mention the possibility.

So the finished function along with test cases:

function hyphenize($string) {
    return 
    ## strtolower(
          preg_replace(
            array('#[\\s-]+#', '#[^A-Za-z0-9. -]+#'),
            array('-', ''),
        ##     cleanString(
              urldecode($string)
        ##     )
        )
    ## )
    ;
}

print implode("\n", array_map(
    function($s) {
            return $s . ' becomes ' . hyphenize($s);
    },
    array(
    'Never%20gonna%20give%20you%20up',
    "I'm not the man I was",
    "'Légeresse', dit sa majesté",
    )));


Never%20gonna%20give%20you%20up    becomes  never-gonna-give-you-up
I'm not the man I was              becomes  im-not-the-man-I-was
'Légeresse', dit sa majesté        becomes  legeresse-dit-sa-majeste

To handle UTF-8 I used a cleanString implementation found online (link broken since, but a stripped down copy with all the not-too-esoteric UTF8 characters is at the beginning of the answer; it's also easy to add more characters to it if you need) that converts UTF8 characters to normal characters, thus preserving the word "look" as much as possible. It could be simplified and wrapped inside the function here for performance.

The function above also implements converting to lowercase - but that's a taste. The code to do so has been commented out.

Get the last three chars from any string - Java

You can use a substring

String word = "onetwotwoone"
int lenght = word.length(); //Note this should be function.
String numbers = word.substring(word.length() - 3);

Jenkins - How to access BUILD_NUMBER environment variable

Assuming I am understanding your question and setup correctly,

If you're trying to use the build number in your script, you have two options:

1) When calling ant, use: ant -Dbuild_parameter=${BUILD_NUMBER}

2) Change your script so that:

<property environment="env" />
<property name="build_parameter"  value="${env.BUILD_NUMBER}"/>

How to make PDF file downloadable in HTML link?

I know I am very late to answer this but I found a hack to do this in javascript.

function downloadFile(src){
    var link=document.createElement('a');
    document.body.appendChild(link);
    link.href= src;
    link.download = '';
    link.click();
}

Disable ONLY_FULL_GROUP_BY

with MySQL version 5.7.28 check by using
SELECT @@sql_mode; and update with

SET @@sql_mode = 'STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION'

echo key and value of an array without and with loop

How to echo key and value of an array without and with loop

$keys = array_keys($page);
implode(',',$keys);
echo $keys[0].' is at '.$page['Home'];

How to run the sftp command with a password from Bash script?

You can use sshpass for it. Below are the steps

  1. Install sshpass For Ubuntu - sudo apt-get install sshpass
  2. Add the Remote IP to your known-host file if it is first time For Ubuntu -> ssh user@IP -> enter 'yes'
  3. give a combined command of scp and sshpass for it. Below is a sample code for war coping to remote tomcat sshpass -p '#Password_For_remote_machine' scp /home/ubuntu/latest_build/abc.war #user@#RemoteIP:/var/lib/tomcat7/webapps

How to display an image stored as byte array in HTML/JavaScript?

Try putting this HTML snippet into your served document:

<img id="ItemPreview" src="">

Then, on JavaScript side, you can dynamically modify image's src attribute with so-called Data URL.

document.getElementById("ItemPreview").src = "data:image/png;base64," + yourByteArrayAsBase64;

Alternatively, using jQuery:

$('#ItemPreview').attr('src', `data:image/png;base64,${yourByteArrayAsBase64}`);

This assumes that your image is stored in PNG format, which is quite popular. If you use some other image format (e.g. JPEG), modify the MIME type ("image/..." part) in the URL accordingly.

Similar Questions:

How to delete a cookie?

To delete a cookie I set it again with an empty value and expiring in 1 second. In details, I always use one of the following flavours (I tend to prefer the second one):

1.

    function setCookie(key, value, expireDays, expireHours, expireMinutes, expireSeconds) {
        var expireDate = new Date();
        if (expireDays) {
            expireDate.setDate(expireDate.getDate() + expireDays);
        }
        if (expireHours) {
            expireDate.setHours(expireDate.getHours() + expireHours);
        }
        if (expireMinutes) {
            expireDate.setMinutes(expireDate.getMinutes() + expireMinutes);
        }
        if (expireSeconds) {
            expireDate.setSeconds(expireDate.getSeconds() + expireSeconds);
        }
        document.cookie = key +"="+ escape(value) +
            ";domain="+ window.location.hostname +
            ";path=/"+
            ";expires="+expireDate.toUTCString();
    }

    function deleteCookie(name) {
        setCookie(name, "", null , null , null, 1);
    }

Usage:

setCookie("reminder", "buyCoffee", null, null, 20);
deleteCookie("reminder");

2

    function setCookie(params) {
        var name            = params.name,
            value           = params.value,
            expireDays      = params.days,
            expireHours     = params.hours,
            expireMinutes   = params.minutes,
            expireSeconds   = params.seconds;

        var expireDate = new Date();
        if (expireDays) {
            expireDate.setDate(expireDate.getDate() + expireDays);
        }
        if (expireHours) {
            expireDate.setHours(expireDate.getHours() + expireHours);
        }
        if (expireMinutes) {
            expireDate.setMinutes(expireDate.getMinutes() + expireMinutes);
        }
        if (expireSeconds) {
            expireDate.setSeconds(expireDate.getSeconds() + expireSeconds);
        }

        document.cookie = name +"="+ escape(value) +
            ";domain="+ window.location.hostname +
            ";path=/"+
            ";expires="+expireDate.toUTCString();
    }

    function deleteCookie(name) {
        setCookie({name: name, value: "", seconds: 1});
    }

Usage:

setCookie({name: "reminder", value: "buyCoffee", minutes: 20});
deleteCookie("reminder");

What are App Domains in Facebook Apps?

It's simply the domain that your "facebook" application (wich means application visible on facebook but hosted on the website www.xyz.com) will be hosted. So you can put App Domain = www.xyz.com

How can I use a batch file to write to a text file?

echo "blahblah"> txt.txt will erase the txt and put blahblah in it's place

echo "blahblah">> txt.txt will write blahblah on a new line in the txt

I think that both will create a new txt if none exists (I know that the first one does)

Where "txt.txt" is written above, a file path can be inserted if wanted. e.g. C:\Users\<username>\desktop, which will put it on their desktop.

How line ending conversions work with git core.autocrlf between different operating systems

Things are about to change on the "eol conversion" front, with the upcoming Git 1.7.2:

A new config setting core.eol is being added/evolved:

This is a replacement for the 'Add "core.eol" config variable' commit that's currently in pu (the last one in my series).
Instead of implying that "core.autocrlf=true" is a replacement for "* text=auto", it makes explicit the fact that autocrlf is only for users who want to work with CRLFs in their working directory on a repository that doesn't have text file normalization.
When it is enabled, "core.eol" is ignored.

Introduce a new configuration variable, "core.eol", that allows the user to set which line endings to use for end-of-line-normalized files in the working directory.
It defaults to "native", which means CRLF on Windows and LF everywhere else. Note that "core.autocrlf" overrides core.eol.
This means that:

[core]
  autocrlf = true

puts CRLFs in the working directory even if core.eol is set to "lf".

core.eol:

Sets the line ending type to use in the working directory for files that have the text property set.
Alternatives are 'lf', 'crlf' and 'native', which uses the platform's native line ending.
The default value is native.


Other evolutions are being considered:

For 1.8, I would consider making core.autocrlf just turn on normalization and leave the working directory line ending decision to core.eol, but that will break people's setups.


git 2.8 (March 2016) improves the way core.autocrlf influences the eol:

See commit 817a0c7 (23 Feb 2016), commit 6e336a5, commit df747b8, commit df747b8 (10 Feb 2016), commit df747b8, commit df747b8 (10 Feb 2016), and commit 4b4024f, commit bb211b4, commit 92cce13, commit 320d39c, commit 4b4024f, commit bb211b4, commit 92cce13, commit 320d39c (05 Feb 2016) by Torsten Bögershausen (tboegi).
(Merged by Junio C Hamano -- gitster -- in commit c6b94eb, 26 Feb 2016)

convert.c: refactor crlf_action

Refactor the determination and usage of crlf_action.
Today, when no "crlf" attribute are set on a file, crlf_action is set to CRLF_GUESS. Use CRLF_UNDEFINED instead, and search for "text" or "eol" as before.

Replace the old CRLF_GUESS usage:

CRLF_GUESS && core.autocrlf=true -> CRLF_AUTO_CRLF
CRLF_GUESS && core.autocrlf=false -> CRLF_BINARY
CRLF_GUESS && core.autocrlf=input -> CRLF_AUTO_INPUT

Make more clear, what is what, by defining:

- CRLF_UNDEFINED : No attributes set. Temparally used, until core.autocrlf
                   and core.eol is evaluated and one of CRLF_BINARY,
                   CRLF_AUTO_INPUT or CRLF_AUTO_CRLF is selected
- CRLF_BINARY    : No processing of line endings.
- CRLF_TEXT      : attribute "text" is set, line endings are processed.
- CRLF_TEXT_INPUT: attribute "input" or "eol=lf" is set. This implies text.
- CRLF_TEXT_CRLF : attribute "eol=crlf" is set. This implies text.
- CRLF_AUTO      : attribute "auto" is set.
- CRLF_AUTO_INPUT: core.autocrlf=input (no attributes)
- CRLF_AUTO_CRLF : core.autocrlf=true  (no attributes)

As torek adds in the comments:

all these translations (any EOL conversion from eol= or autocrlf settings, and "clean" filters) are run when files move from work-tree to index, i.e., during git add rather than at git commit time.
(Note that git commit -a or --only or --include do add files to the index at that time, though.)

For more on that, see "What is difference between autocrlf and eol".

PHP: Return all dates between two dates in an array

function datesbetween ($date1,$date2)
{
    $dates= array();
    for ($i = $date1
       ; $i<= $date1
       ; $i=date_add($i, date_interval_create_from_date_string('1 days')) ) 
    {            
       $dates[] = clone $i;
    }
    return $dates;
}

Deep-Learning Nan loss reasons

Although most of the points are already discussed. But I would like to highlight again one more reason for NaN which is missing.

tf.estimator.DNNClassifier(
    hidden_units, feature_columns, model_dir=None, n_classes=2, weight_column=None,
    label_vocabulary=None, optimizer='Adagrad', activation_fn=tf.nn.relu,
    dropout=None, config=None, warm_start_from=None,
    loss_reduction=losses_utils.ReductionV2.SUM_OVER_BATCH_SIZE, batch_norm=False
)

By default activation function is "Relu". It could be possible that intermediate layer's generating a negative value and "Relu" convert it into the 0. Which gradually stops training.

I observed the "LeakyRelu" able to solve such problems.

Restful API service

I know @Martyn does not want full code, but I think this annotation its good for this question:

10 Open Source Android Apps which every Android developer must look into

Foursquared for Android is open-source, and have an interesting code pattern interacting with the foursquare REST API.

sort json object in javascript

First off, that's not JSON. It's a JavaScript object literal. JSON is a string representation of data, that just so happens to very closely resemble JavaScript syntax.

Second, you have an object. They are unsorted. The order of the elements cannot be guaranteed. If you want guaranteed order, you need to use an array. This will require you to change your data structure.

One option might be to make your data look like this:

var json = [{
    "name": "user1",
    "id": 3
}, {
    "name": "user2",
    "id": 6
}, {
    "name": "user3",
    "id": 1
}];

Now you have an array of objects, and we can sort it.

json.sort(function(a, b){
    return a.id - b.id;
});

The resulting array will look like:

[{
    "name": "user3",
    "id" : 1
}, {
    "name": "user1",
    "id" : 3
}, {
    "name": "user2",
    "id" : 6
}];

Get the _id of inserted document in Mongo database in NodeJS

A shorter way than using second parameter for the callback of collection.insert would be using objectToInsert._id that returns the _id (inside of the callback function, supposing it was a successful operation).

The Mongo driver for NodeJS appends the _id field to the original object reference, so it's easy to get the inserted id using the original object:

collection.insert(objectToInsert, function(err){
   if (err) return;
   // Object inserted successfully.
   var objectId = objectToInsert._id; // this will return the id of object inserted
});

plot different color for different categorical levels using matplotlib

Here's a succinct and generic solution to use a seaborn color palette.

First find a color palette you like and optionally visualize it:

sns.palplot(sns.color_palette("Set2", 8))

Then you can use it with matplotlib doing this:

# Unique category labels: 'D', 'F', 'G', ...
color_labels = df['color'].unique()

# List of RGB triplets
rgb_values = sns.color_palette("Set2", 8)

# Map label to RGB
color_map = dict(zip(color_labels, rgb_values))

# Finally use the mapped values
plt.scatter(df['carat'], df['price'], c=df['color'].map(color_map))

Find the location of a character in string

Here's another straightforward alternative.

> which(strsplit(string, "")[[1]]=="2")
[1]  4 24

New features in java 7

The following list contains links to the the enhancements pages in the Java SE 7.

Swing
IO and New IO
Networking
Security
Concurrency Utilities
Rich Internet Applications (RIA)/Deployment
    Requesting and Customizing Applet Decoration in Dragg able Applets
    Embedding JNLP File in Applet Tag
    Deploying without Codebase
    Handling Applet Initialization Status with Event Handlers
Java 2D
Java XML – JAXP, JAXB, and JAX-WS
Internationalization
java.lang Package
    Multithreaded Custom Class Loaders in Java SE 7
Java Programming Language
    Binary Literals
    Strings in switch Statements
    The try-with-resources Statement
    Catching Multiple Exception Types and Rethrowing Exceptions with Improved Type Checking
    Underscores in Numeric Literals
    Type Inference for Generic Instance Creation
    Improved Compiler Warnings and Errors When Using Non-Reifiable Formal Parameters with Varargs Methods
Java Virtual Machine (JVM)
    Java Virtual Machine Support for Non-Java Languages
    Garbage-First Collector
    Java HotSpot Virtual Machine Performance Enhancements
JDBC

Reference 1 Reference 2

How does Python return multiple values from a function?

Here It is actually returning tuple.

If you execute this code in Python 3:

def get():
    a = 3
    b = 5
    return a,b
number = get()
print(type(number))
print(number)

Output :

<class 'tuple'>
(3, 5)

But if you change the code line return [a,b] instead of return a,b and execute :

def get():
    a = 3
    b = 5
    return [a,b]
number = get()
print(type(number))
print(number)

Output :

<class 'list'>
[3, 5]

It is only returning single object which contains multiple values.

There is another alternative to return statement for returning multiple values, use yield( to check in details see this What does the "yield" keyword do in Python?)

Sample Example :

def get():
    for i in range(5):
        yield i
number = get()
print(type(number))
print(number)
for i in number:
    print(i)

Output :

<class 'generator'>
<generator object get at 0x7fbe5a1698b8>
0
1
2
3
4

How do I find duplicates across multiple columns?

Duplicated id for pairs name and city:

select s.id, t.* 
from [stuff] s
join (
    select name, city, count(*) as qty
    from [stuff]
    group by name, city
    having count(*) > 1
) t on s.name = t.name and s.city = t.city

Disable native datepicker in Google Chrome

This works for me:

;
(function ($) {
    $(document).ready(function (event) {
        $(document).on('click input', 'input[type="date"], input[type="text"].date-picker', function (e) {
            var $this = $(this);
            $this.prop('type', 'text').datepicker({
                showOtherMonths: true,
                selectOtherMonths: true,
                showButtonPanel: true,
                changeMonth: true,
                changeYear: true,
                dateFormat: 'yy-mm-dd',
                showWeek: true,
                firstDay: 1
            });

            setTimeout(function() {
                $this.datepicker('show');
            }, 1);
        });
    });
})(jQuery, jQuery.ui);

See also:

How can I disable the new Chrome HTML5 date input?

http://zizhujy.com/blog/post/2014/09/18/Add-date-picker-to-dynamically-generated-input-elements.aspx

How can I give an imageview click effect like a button on Android?

You can do that by adding this attr

 android:background="?android:attr/selectableItemBackground"/

into your

Where's my invalid character (ORA-00911)

Of the top of my head, can you try to use the 'q' operator for the string literal

something like

insert all
  into domo_queries values (q'[select 
substr(to_char(max_data),1,4) as year,
substr(to_char(max_data),5,6) as month,
max_data
from dss_fin_user.acq_dashboard_src_load_success
where source = 'CHQ PeopleSoft FS']')
select * from dual;

Note that the single quotes of your predicate are not escaped, and the string sits between q'[...]'.

ImportError: No module named 'Queue'

I run into the same problem and learn that queue module defines classes and exceptions, that defines the public methods (Queue Objects).

Ex.

workQueue = queue.Queue(10)

c#: getter/setter

With the release of C# 6, you can now do something like this for private properties.

public constructor()
{
   myProp = "some value";
}

public string myProp { get; }

How do I toggle an element's class in pure JavaScript?

Try this (hopefully it will work):

// mixin (functionality) for toggle class 
function hasClass(ele, clsName) {
    var el = ele.className;
    el = el.split(' ');
    if(el.indexOf(clsName) > -1){
        var cIndex = el.indexOf(clsName);
        el.splice(cIndex, 1);
        ele.className = " ";
        el.forEach(function(item, index){
          ele.className += " " + item;
        })
    }
    else {
        el.push(clsName);
        ele.className = " ";
        el.forEach(function(item, index){
          ele.className += " " + item;
        })
    }
}

// get all DOM element that we need for interactivity.

var btnNavbar =  document.getElementsByClassName('btn-navbar')[0];
var containerFluid =  document.querySelector('.container-fluid:first');
var menu = document.getElementById('menu');

// on button click job
btnNavbar.addEventListener('click', function(){
    hasClass(containerFluid, 'menu-hidden');
    hasClass(menu, 'hidden-phone');
})`enter code here`

mvn clean install vs. deploy vs. release

  • mvn install will put your packaged maven project into the local repository, for local application using your project as a dependency.
  • mvn release will basically put your current code in a tag on your SCM, change your version in your projects.
  • mvn deploy will put your packaged maven project into a remote repository for sharing with other developers.

Resources :

Sending HTML email using Python

Here's sample code. This is inspired from code found on the Python Cookbook site (can't find the exact link)

def createhtmlmail (html, text, subject, fromEmail):
    """Create a mime-message that will render HTML in popular
    MUAs, text in better ones"""
    import MimeWriter
    import mimetools
    import cStringIO

    out = cStringIO.StringIO() # output buffer for our message 
    htmlin = cStringIO.StringIO(html)
    txtin = cStringIO.StringIO(text)

    writer = MimeWriter.MimeWriter(out)
    #
    # set up some basic headers... we put subject here
    # because smtplib.sendmail expects it to be in the
    # message body
    #
    writer.addheader("From", fromEmail)
    writer.addheader("Subject", subject)
    writer.addheader("MIME-Version", "1.0")
    #
    # start the multipart section of the message
    # multipart/alternative seems to work better
    # on some MUAs than multipart/mixed
    #
    writer.startmultipartbody("alternative")
    writer.flushheaders()
    #
    # the plain text section
    #
    subpart = writer.nextpart()
    subpart.addheader("Content-Transfer-Encoding", "quoted-printable")
    pout = subpart.startbody("text/plain", [("charset", 'us-ascii')])
    mimetools.encode(txtin, pout, 'quoted-printable')
    txtin.close()
    #
    # start the html subpart of the message
    #
    subpart = writer.nextpart()
    subpart.addheader("Content-Transfer-Encoding", "quoted-printable")
    #
    # returns us a file-ish object we can write to
    #
    pout = subpart.startbody("text/html", [("charset", 'us-ascii')])
    mimetools.encode(htmlin, pout, 'quoted-printable')
    htmlin.close()
    #
    # Now that we're done, close our writer and
    # return the message body
    #
    writer.lastpart()
    msg = out.getvalue()
    out.close()
    print msg
    return msg

if __name__=="__main__":
    import smtplib
    html = 'html version'
    text = 'TEST VERSION'
    subject = "BACKUP REPORT"
    message = createhtmlmail(html, text, subject, 'From Host <[email protected]>')
    server = smtplib.SMTP("smtp_server_address","smtp_port")
    server.login('username', 'password')
    server.sendmail('[email protected]', '[email protected]', message)
    server.quit()

How can I use UIColorFromRGB in Swift?

You cannot use a complex macros like #define UIColorFromRGB(rgbValue) in swift. The replacement of simple macro in swift is global constants like

let FADE_ANIMATION_DURATION = 0.35

Still the complex macros that accept parameters are not supported by swift. you could use functions instead

Complex macros are used in C and Objective-C but have no counterpart in Swift. Complex macros are macros that do not define constants, including parenthesized, function-like macros. You use complex macros in C and Objective-C to avoid type-checking constraints or to avoid retyping large amounts of boilerplate code. However, macros can make debugging and refactoring difficult. In Swift, you can use functions and generics to achieve the same results without any compromises. Therefore, the complex macros that are in C and Objective-C source files are not made available to your Swift code.

Excerpt from Using swift with cocoa and objective C

Check @Nate Cooks answer for the Swift version of that function to be used here

git rm - fatal: pathspec did not match any files

Step 1

Add the file name(s) to your .gitignore file.

Step 2

git filter-branch --force --index-filter \
    'git rm -r --cached --ignore-unmatch YOURFILE' \
    --prune-empty --tag-name-filter cat -- --all

Step 3

git push -f origin branch

A big thank you to @mu.

round() doesn't seem to be rounding properly

I would avoid relying on round() at all in this case. Consider

print(round(61.295, 2))
print(round(1.295, 2))

will output

61.3
1.29

which is not a desired output if you need solid rounding to the nearest integer. To bypass this behavior go with math.ceil() (or math.floor() if you want to round down):

from math import ceil
decimal_count = 2
print(ceil(61.295 * 10 ** decimal_count) / 10 ** decimal_count)
print(ceil(1.295 * 10 ** decimal_count) / 10 ** decimal_count)

outputs

61.3
1.3

Hope that helps.

How to view file history in Git?

you could also use tig for a nice, ncurses-based git repository browser. To view history of a file:

tig path/to/file

jQuery textbox change event

$('#input').on("input",function () {alert('changed');});

works for me.

Uploading an Excel sheet and importing the data into SQL Server database

    public async Task<HttpResponseMessage> PostFormDataAsync()    //async is used for defining an asynchronous method
    {
        if (!Request.Content.IsMimeMultipartContent())
        {
            throw new HttpResponseException(HttpStatusCode.UnsupportedMediaType);
        }
        var fileLocation = "";
        string root = HttpContext.Current.Server.MapPath("~/App_Data");
        MultipartFormDataStreamProvider provider = new MultipartFormDataStreamProvider(root);  //Helps in HTML file uploads to write data to File Stream
        try
        {
            // Read the form data.
        await Request.Content.ReadAsMultipartAsync(provider);

            // This illustrates how to get the file names.
            foreach (MultipartFileData file in provider.FileData)
            {
                Trace.WriteLine(file.Headers.ContentDisposition.FileName); //Gets the file name
                var filePath = file.Headers.ContentDisposition.FileName.Substring(1, file.Headers.ContentDisposition.FileName.Length - 2); //File name without the path
                File.Copy(file.LocalFileName, file.LocalFileName + filePath); //Save a copy for reading it
                fileLocation = file.LocalFileName + filePath; //Complete file location
            }
    HttpResponseMessage response = Request.CreateResponse(HttpStatusCode.OK, recordStatus);
            return response;
}
catch (System.Exception e)
    {
            return Request.CreateErrorResponse(HttpStatusCode.InternalServerError, e);
    }
}
public void ReadFromExcel()
{
try
        {
            DataTable sheet1 = new DataTable();
            OleDbConnectionStringBuilder csbuilder = new OleDbConnectionStringBuilder();
            csbuilder.Provider = "Microsoft.ACE.OLEDB.12.0";
            csbuilder.DataSource = fileLocation;
            csbuilder.Add("Extended Properties", "Excel 12.0 Xml;HDR=YES");
            string selectSql = @"SELECT * FROM [Sheet1$]";
            using (OleDbConnection connection = new OleDbConnection(csbuilder.ConnectionString))
            using (OleDbDataAdapter adapter = new OleDbDataAdapter(selectSql, connection))
            {
                connection.Open();
                adapter.Fill(sheet1);
            }
        }
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }          
}

Can you have multiple $(document).ready(function(){ ... }); sections?

Yes, it's perfectly ok.but avoid doing it without a reason. For example I used it to declare global site rules seperately than indivual pages when my javascript files were generated dynamically but if you just keep doing it over and over it will make it hard to read.

Also you can not access some methods from another jQuery(function(){}); call so that's another reason you don't wanna do that.

With the old window.onload though you will replace the old one every time you specified a function.

How to convert string to double with proper cultureinfo

You need to define a single locale that you will use for the data stored in the database, the invariant culture is there for exactly this purpose.

When you display convert to the native type and then format for the user's culture.

E.g. to display:

string fromDb = "123.56";
string display = double.Parse(fromDb, CultureInfo.InvariantCulture).ToString(userCulture);

to store:

string fromUser = "132,56";
double value;
// Probably want to use a more specific NumberStyles selection here.
if (!double.TryParse(fromUser, NumberStyles.Any, userCulture, out value)) {
  // Error...
}
string forDB = value.ToString(CultureInfo.InvariantCulture);

PS. It, almost, goes without saying that using a column with a datatype that matches the data would be even better (but sometimes legacy applies).

Difference between $.ajax() and $.get() and $.load()

http://api.jquery.com/jQuery.ajax/

jQuery.ajax()

Description: Perform an asynchronous HTTP (Ajax) request.

The full monty, lets you make any kind of Ajax request.


http://api.jquery.com/jQuery.get/

jQuery.get()

Description: Load data from the server using a HTTP GET request.

Only lets you make HTTP GET requests, requires a little less configuration.


http://api.jquery.com/load/

.load()

Description: Load data from the server and place the returned HTML into the matched element.

Specialized to get data and inject it into an element.

When would you use the Builder Pattern?

Below are some reasons arguing for the use of the pattern and example code in Java, but it is an implementation of the Builder Pattern covered by the Gang of Four in Design Patterns. The reasons you would use it in Java are also applicable to other programming languages as well.

As Joshua Bloch states in Effective Java, 2nd Edition:

The builder pattern is a good choice when designing classes whose constructors or static factories would have more than a handful of parameters.

We've all at some point encountered a class with a list of constructors where each addition adds a new option parameter:

Pizza(int size) { ... }        
Pizza(int size, boolean cheese) { ... }    
Pizza(int size, boolean cheese, boolean pepperoni) { ... }    
Pizza(int size, boolean cheese, boolean pepperoni, boolean bacon) { ... }

This is called the Telescoping Constructor Pattern. The problem with this pattern is that once constructors are 4 or 5 parameters long it becomes difficult to remember the required order of the parameters as well as what particular constructor you might want in a given situation.

One alternative you have to the Telescoping Constructor Pattern is the JavaBean Pattern where you call a constructor with the mandatory parameters and then call any optional setters after:

Pizza pizza = new Pizza(12);
pizza.setCheese(true);
pizza.setPepperoni(true);
pizza.setBacon(true);

The problem here is that because the object is created over several calls it may be in an inconsistent state partway through its construction. This also requires a lot of extra effort to ensure thread safety.

The better alternative is to use the Builder Pattern.

public class Pizza {
  private int size;
  private boolean cheese;
  private boolean pepperoni;
  private boolean bacon;

  public static class Builder {
    //required
    private final int size;

    //optional
    private boolean cheese = false;
    private boolean pepperoni = false;
    private boolean bacon = false;

    public Builder(int size) {
      this.size = size;
    }

    public Builder cheese(boolean value) {
      cheese = value;
      return this;
    }

    public Builder pepperoni(boolean value) {
      pepperoni = value;
      return this;
    }

    public Builder bacon(boolean value) {
      bacon = value;
      return this;
    }

    public Pizza build() {
      return new Pizza(this);
    }
  }

  private Pizza(Builder builder) {
    size = builder.size;
    cheese = builder.cheese;
    pepperoni = builder.pepperoni;
    bacon = builder.bacon;
  }
}

Note that Pizza is immutable and that parameter values are all in a single location. Because the Builder's setter methods return the Builder object they are able to be chained.

Pizza pizza = new Pizza.Builder(12)
                       .cheese(true)
                       .pepperoni(true)
                       .bacon(true)
                       .build();

This results in code that is easy to write and very easy to read and understand. In this example, the build method could be modified to check parameters after they have been copied from the builder to the Pizza object and throw an IllegalStateException if an invalid parameter value has been supplied. This pattern is flexible and it is easy to add more parameters to it in the future. It is really only useful if you are going to have more than 4 or 5 parameters for a constructor. That said, it might be worthwhile in the first place if you suspect you may be adding more parameters in the future.

I have borrowed heavily on this topic from the book Effective Java, 2nd Edition by Joshua Bloch. To learn more about this pattern and other effective Java practices I highly recommend it.

Private Variables and Methods in Python

Double underscore. That mangles the name. The variable can still be accessed, but it's generally a bad idea to do so.

Use single underscores for semi-private (tells python developers "only change this if you absolutely must") and doubles for fully private.

How can I start PostgreSQL on Windows?

Go inside bin folder in C drive where Postgres is installed. run following command in git bash or Command prompt:

pg_ctl.exe restart -D "<path upto data>"

Ex:

pg_ctl.exe restart -D  "C:\Program Files\PostgreSQL\9.6\data"

Another way: type "services.msc" in run popup(windows + R). This will show all services running Select Postgres service from list and click on start/stop/restart.

Thanks

How to get a MemoryStream from a Stream in .NET?

How do I copy the contents of one stream to another?

see that. accept a stream and copy to memory. you should not use .Length for just Stream because it is not necessarily implemented in every concrete Stream.

Difference between signed / unsigned char

The same way how an int can be positive or negative. There is no difference. Actually on many platforms unqualified char is signed.

How do I fit an image (img) inside a div and keep the aspect ratio?

Unfortunately max-width + max-height do not fully cover my task... So I have found another solution:

To save the Image ratio while scaling you also can use object-fit CSS3 propperty.

Useful article: Control image aspect ratios with CSS3

img {
    width: 100%; /* or any custom size */
    height: 100%; 
    object-fit: contain;
}

Bad news: IE not supported (Can I Use)

Including jars in classpath on commandline (javac or apt)

Note for Windows users, the jars should be separated by ; and not :.

for example: javac -cp external_libs\lib1.jar;other\lib2.jar;

ld: framework not found Pods

I had a similar issue as

framework not found Pods_OneSignalNotificationServiceExtension

It was resolved by removing the following. Go to target OneSignalNotificationServiceExtension > Build Phases > Link Binary with Libraries and deleting Pods_OneSignalNotificationServiceExtension.framework It should be empty here. Hope this helps. Cheers.

Error when checking model input: expected convolution2d_input_1 to have 4 dimensions, but got array with shape (32, 32, 3)

I got the same error while working with mnist data set, looks like a problem with the dimensions of X_train. I added another dimension and it solved the purpose.

X_train, X_test, \ y_train, y_test = train_test_split(X_reshaped, y_labels, train_size = 0.8, random_state = 42)

X_train = X_train.reshape(-1,28, 28, 1)

X_test = X_test.reshape(-1,28, 28, 1)

Why doesn't git recognize that my file has been changed, therefore git add not working

TL;DR; Are you even on the correct repository?

My story is bit funny but I thought it can happen with someone who might be having a similar scenario so sharing it here.

Actually on my machine, I had two separate git repositories repo1 and repo2 configured in the same root directory named source. These two repositories are essentially the repositories of two products I work off and on in my company. Now the thing is that as a standard guideline, the directory structure of source code of all the products is exactly the same in my company.

So without realizing I modified an exactly same named file in repo2 which I was supposed to change in repo1. So, I just kept running command git status on repo1 and it kept giving the same message

On branch master

nothing to commit, working directory clean

for half an hour. Then colleague of mine observed it as independent pair of eyes and brought this thing to my notice that I was in wrong but very similar looking repository. The moment I switched to repo1 Git started noticing the changed files.

Not so common case. But you never know!

How can I debug my JavaScript code?

Visual Studio 2008 has some very good JavaScript debugging tools. You can drop a breakpoint in your client side JavaScript code and step through it using the exact same tools as you would the server side code. There is no need to attach to a process or do anything tricky to enable it.

Copying files to a container with Docker Compose

Given

    volumes:
      - /dir/on/host:/var/www/html

if /dir/on/host doesn't exist, it is created on the host and the empty content is mounted in the container at /var/www/html. Whatever content you had before in /var/www/html inside the container is inaccessible, until you unmount the volume; the new mount is hiding the old content.

Create a dropdown component

If you want to use bootstrap dropdowns, I will recommend this for angular2:

ngx-dropdown

Disable Chrome strict MIME type checking

For Windows Users :

If this issue occurs on your self hosted server (eg: your custom CDN) and the browser (Chrome) says something like ... ('text/plain') is not executable ... when trying to load your javascript file ...

Here is what you need to do :

  1. Open the Registry Editor i.e Win + R > regedit
  2. Head over to HKEY_LOCAL_MACHINE\SOFTWARE\Classes\.js
  3. Check to if the Content Type is application/javascript or not
  4. If not, then change it to application/javascript and try again

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

I use this code:

bool AlmostEqual(double v1, double v2)
    {
        return (std::fabs(v1 - v2) < std::fabs(std::min(v1, v2)) * std::numeric_limits<double>::epsilon());
    }

Why do I get the "Unhandled exception type IOException"?

Try again with this code snippet:

import java.io.*;

class IO {
    public static void main(String[] args) {    
        try {
            BufferedReader stdIn = new BufferedReader(new InputStreamReader(System.in));    
            String userInput;    
            while ((userInput = stdIn.readLine()) != null) {
                System.out.println(userInput);
            }
        } catch(IOException ie) {
            ie.printStackTrace();
        }   
    }
}

Using try-catch-finally is better than using throws. Finding errors and debugging are easier when you use try-catch-finally.

Byte and char conversion in Java

A character in Java is a Unicode code-unit which is treated as an unsigned number. So if you perform c = (char)b the value you get is 2^16 - 56 or 65536 - 56.

Or more precisely, the byte is first converted to a signed integer with the value 0xFFFFFFC8 using sign extension in a widening conversion. This in turn is then narrowed down to 0xFFC8 when casting to a char, which translates to the positive number 65480.

From the language specification:

5.1.4. Widening and Narrowing Primitive Conversion

First, the byte is converted to an int via widening primitive conversion (§5.1.2), and then the resulting int is converted to a char by narrowing primitive conversion (§5.1.3).


To get the right point use char c = (char) (b & 0xFF) which first converts the byte value of b to the positive integer 200 by using a mask, zeroing the top 24 bits after conversion: 0xFFFFFFC8 becomes 0x000000C8 or the positive number 200 in decimals.


Above is a direct explanation of what happens during conversion between the byte, int and char primitive types.

If you want to encode/decode characters from bytes, use Charset, CharsetEncoder, CharsetDecoder or one of the convenience methods such as new String(byte[] bytes, Charset charset) or String#toBytes(Charset charset). You can get the character set (such as UTF-8 or Windows-1252) from StandardCharsets.

postgresql duplicate key violates unique constraint

I have similar problem but I solved it by removing all the foreign key in my Postgresql

Value does not fall within the expected range

I had from a totaly different reason the same notice "Value does not fall within the expected range" from the Visual studio 2008 while trying to use the: Tools -> Windows Embedded Silverlight Tools -> Update Silverlight For Windows Embedded Project.

After spending many ohurs I found out that the problem was that there wasn't a resource file and the update tool looks for the .RC file

Therefor the solution is to add to the resource folder a .RC file and than it works perfectly. I hope it will help someone out there

How to unlock android phone through ADB

If you had MyPhoneExplorer installed and connected (not sure this is a must, happened to be my setup already), you could use it to control the screen with your computer mouse. It connects via ADB, for which your normal USB cable is enough.

Another solution I found that even worked without a reboot is updating tables in settings.db and locksettings.db I had to switch to root to open the settings.db though:

 adb shell
 su
 sqlite3 /data/data/com.android.providers.settings/databases/settings.db
 update secure set value=1 where name='lockscreen.disabled';
 .quit
 sqlite3 /data/system/locksettings.db
 update locksettings set value=0 where name='lock_pattern_autlock';
 update locksettings set value=1 where name='lockscreen.disabled';
 .quit

Source that made me edit my tables

Getting the textarea value of a ckeditor textarea with javascript

var campaignTitle= CKEDITOR.instances['CampaignTitle'].getData();

How to know function return type and argument types?

Yes it is.

In Python a function doesn't always have to return a variable of the same type (although your code will be more readable if your functions do always return the same type). That means that you can't specify a single return type for the function.

In the same way, the parameters don't always have to be the same type too.