Programs & Examples On #Microblaze

The MicroBlaze is an open (usage documentation is available, but closed source) soft core Processor designed by Xilinx for their FPGAs. It is optimized for space usage and execution for Xilinx's FPGAs.

Regex: Use start of line/end of line signs (^ or $) in different context

Just use look-arounds to solve this:

(?<=^|,)garp(?=$|,)

The difference with look-arounds and just regular groups are that with regular groups the comma would be part of the match, and with look-arounds it wouldn't. In this case it doesn't make a difference though.

get value from DataTable

You can try changing it to this:

If myTableData.Rows.Count > 0 Then
  For i As Integer = 0 To myTableData.Rows.Count - 1
    ''Dim DataType() As String = myTableData.Rows(i).Item(1)
    ListBox2.Items.Add(myTableData.Rows(i)(1))
  Next
End If

Note: Your loop needs to be one less than the row count since it's a zero-based index.

Get JSF managed bean by name in any Servlet related class

In a servlet based artifact, such as @WebServlet, @WebFilter and @WebListener, you can grab a "plain vanilla" JSF @ManagedBean @RequestScoped by:

Bean bean = (Bean) request.getAttribute("beanName");

and @ManagedBean @SessionScoped by:

Bean bean = (Bean) request.getSession().getAttribute("beanName");

and @ManagedBean @ApplicationScoped by:

Bean bean = (Bean) getServletContext().getAttribute("beanName");

Note that this prerequires that the bean is already autocreated by JSF beforehand. Else these will return null. You'd then need to manually create the bean and use setAttribute("beanName", bean).


If you're able to use CDI @Named instead of the since JSF 2.3 deprecated @ManagedBean, then it's even more easy, particularly because you don't anymore need to manually create the beans:

@Inject
private Bean bean;

Note that this won't work when you're using @Named @ViewScoped because the bean can only be identified by JSF view state and that's only available when the FacesServlet has been invoked. So in a filter which runs before that, accessing an @Injected @ViewScoped will always throw ContextNotActiveException.


Only when you're inside @ManagedBean, then you can use @ManagedProperty:

@ManagedProperty("#{bean}")
private Bean bean;

Note that this doesn't work inside a @Named or @WebServlet or any other artifact. It really works inside @ManagedBean only.


If you're not inside a @ManagedBean, but the FacesContext is readily available (i.e. FacesContext#getCurrentInstance() doesn't return null), you can also use Application#evaluateExpressionGet():

FacesContext context = FacesContext.getCurrentInstance();
Bean bean = context.getApplication().evaluateExpressionGet(context, "#{beanName}", Bean.class);

which can be convenienced as follows:

@SuppressWarnings("unchecked")
public static <T> T findBean(String beanName) {
    FacesContext context = FacesContext.getCurrentInstance();
    return (T) context.getApplication().evaluateExpressionGet(context, "#{" + beanName + "}", Object.class);
}

and can be used as follows:

Bean bean = findBean("bean");

See also:

How to use Collections.sort() in Java?

Use this method Collections.sort(List,Comparator) . Implement a Comparator and pass it to Collections.sort().

class RecipeCompare implements Comparator<Recipe> {

    @Override
    public int compare(Recipe o1, Recipe o2) {
        // write comparison logic here like below , it's just a sample
        return o1.getID().compareTo(o2.getID());
    }
}

Then use the Comparator as

Collections.sort(recipes,new RecipeCompare());

MySQL: How to copy rows, but change a few fields?

As long as Event_ID is Integer, do this:

INSERT INTO Table (foo, bar, Event_ID)
SELECT foo, bar, (Event_ID + 155)
  FROM Table
WHERE Event_ID = "120"

Evaluate empty or null JSTL c tags

Here's an example of how to validate a int and a String that you pass from the Java Controller to the JSP file.

MainController.java:

@RequestMapping(value="/ImportJavaToJSP")
public ModelAndView getImportJavaToJSP() {
    ModelAndView model2= new ModelAndView("importJavaToJSPExamples");

    int someNumberValue=6;
    String someStringValue="abcdefg";
    //model2.addObject("someNumber", someNumberValue);
    model2.addObject("someString", someStringValue);

    return model2;
}

importJavaToJSPExamples.jsp

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<p>${someNumber}</p>
<c:if test="${not empty someNumber}">
    <p>someNumber is Not Empty</p>
</c:if>
<c:if test="${empty someNumber}">
    <p>someNumber is Empty</p>
</c:if>
<p>${someString}</p>
<c:if test="${not empty someString}">
    <p>someString is Not Empty</p>
</c:if>
<c:if test="${empty someString}">
    <p>someString is Empty</p>
</c:if>

How do I expand the output display to see more columns of a pandas DataFrame?

If you don't want to mess with your display options and you just want to see this one particular list of columns without expanding out every dataframe you view, you could try:

df.columns.values

How to convert HTML file to word?

When doing this I found it easiest to:

  1. Visit the page in a web browser
  2. Save the page using the web browser with .htm extension (and maybe a folder with support files)
  3. Start Word and open the saved htmfile (Word will open it correctly)
  4. Make any edits if needed
  5. Select Save As and then choose the extension you would like doc, docx, etc.

How does setTimeout work in Node.JS?

setTimeout is a kind of Thread, it holds a operation for a given time and execute.

setTimeout(function,time_in_mills);

in here the first argument should be a function type; as an example if you want to print your name after 3 seconds, your code should be something like below.

setTimeout(function(){console.log('your name')},3000);

Key point to remember is, what ever you want to do by using the setTimeout method, do it inside a function. If you want to call some other method by parsing some parameters, your code should look like below:

setTimeout(function(){yourOtherMethod(parameter);},3000);

How to configure CORS in a Spring Boot + Spring Security application?

If you are using Spring Security, you can do the following to ensure that CORS requests are handled first:

@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http
            // by default uses a Bean by the name of corsConfigurationSource
            .cors().and()
            ...
    }

    @Bean
    CorsConfigurationSource corsConfigurationSource() {
        CorsConfiguration configuration = new CorsConfiguration();
        configuration.setAllowedOrigins(Arrays.asList("https://example.com"));
        configuration.setAllowedMethods(Arrays.asList("GET","POST"));
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        source.registerCorsConfiguration("/**", configuration);
        return source;
    }
}

See Spring 4.2.x CORS for more information.

Without Spring Security this will work:

@Bean
public WebMvcConfigurer corsConfigurer() {
    return new WebMvcConfigurer() {
        @Override
        public void addCorsMappings(CorsRegistry registry) {
            registry.addMapping("/**")
                    .allowedOrigins("*")
                    .allowedMethods("GET", "PUT", "POST", "PATCH", "DELETE", "OPTIONS");
        }
    };
}

How to get the selected date value while using Bootstrap Datepicker?

Bootstrap datepicker (the first result from bootstrap datepickcer search) has a method to get the selected date.
https://bootstrap-datepicker.readthedocs.io/en/latest/methods.html#getdate

getDate: Returns a localized date object representing the internal date object of the first datepicker in the selection. For multidate pickers, returns the latest date selected.

$('.datepicker').datepicker("getDate")

or

$('.datepicker').datepicker("getDate").valueOf() 

How do I pick randomly from an array?

Random Number of Random Items from an Array

def random_items(array)
  array.sample(1 + rand(array.count))
end

Examples of possible results:

my_array = ["one", "two", "three"]
my_array.sample(1 + rand(my_array.count))

=> ["two", "three"]
=> ["one", "three", "two"]
=> ["two"]

How to set up gradle and android studio to do release build?

No need to update gradle for making release application in Android studio.If you were eclipse user then it will be so easy for you. If you are new then follow the steps

1: Go to the "Build" at the toolbar section. 2: Choose "Generate Signed APK..." option. enter image description here

3:fill opened form and go next 4 :if you already have .keystore or .jks then choose that file enter your password and alias name and respective password. 5: Or don't have .keystore or .jks file then click on Create new... button as shown on pic 1 then fill the form.enter image description here

Above process was to make build manually. If You want android studio to automatically Signing Your App

In Android Studio, you can configure your project to sign your release APK automatically during the build process:

On the project browser, right click on your app and select Open Module Settings. On the Project Structure window, select your app's module under Modules. Click on the Signing tab. Select your keystore file, enter a name for this signing configuration (as you may create more than one), and enter the required information. enter image description here Figure 4. Create a signing configuration in Android Studio.

Click on the Build Types tab. Select the release build. Under Signing Config, select the signing configuration you just created. enter image description here Figure 5. Select a signing configuration in Android Studio.

4:Most Important thing that make debuggable=false at gradle.

    buildTypes {
        release {
           minifyEnabled false
          proguardFiles getDefaultProguardFile('proguard-  android.txt'), 'proguard-rules.txt'
        debuggable false
        jniDebuggable false
        renderscriptDebuggable false
        zipAlignEnabled true
       }
     }

visit for more in info developer.android.com

How do I download/extract font from chrome developers tools?

I found the Chrome option to be OK but there are quite a few steps to go through to get to the font files. Once you're there, the downloading is super easy. I usually use the dev tools in Safari as there are fewer steps. Just go to the page you want, click on "Show page source" or "show page resources" in the Developer menu (both work for this) and the page resources are listed in folders on the left hand side. Click the font folder and the fonts are listed. Right click and save file. If you are downloading a lot of font files from one site it may be quicker to work your way through Chrome's pathway as the "open in tab" does download the fonts quicker. If you're taking one or two fonts from a lot of different sites, Safari will be quicker overall.

Show percent % instead of counts in charts of categorical variables

Since this was answered there have been some meaningful changes to the ggplot syntax. Summing up the discussion in the comments above:

 require(ggplot2)
 require(scales)

 p <- ggplot(mydataf, aes(x = foo)) +  
        geom_bar(aes(y = (..count..)/sum(..count..))) + 
        ## version 3.0.0
        scale_y_continuous(labels=percent)

Here's a reproducible example using mtcars:

 ggplot(mtcars, aes(x = factor(hp))) +  
        geom_bar(aes(y = (..count..)/sum(..count..))) + 
        scale_y_continuous(labels = percent) ## version 3.0.0

enter image description here

This question is currently the #1 hit on google for 'ggplot count vs percentage histogram' so hopefully this helps distill all the information currently housed in comments on the accepted answer.

Remark: If hp is not set as a factor, ggplot returns:

enter image description here

How can I check which version of Angular I'm using?

For AngularJS - Use angular.version

_x000D_
_x000D_
console.log(angular.version);
_x000D_
<script src="//unpkg.com/angular/angular.js"></script>
_x000D_
_x000D_
_x000D_

For more information, see

How to use UIPanGestureRecognizer to move object? iPhone/iPad

if ([recognizer state] == UIGestureRecognizerStateChanged)    
{
    CGPoint translation1 = [recognizer translationInView:main_view];
    img12.center=CGPointMake(img12.center.x+translation1.x, img12.center.y+ translation1.y);
    [recognizer setTranslation:CGPointMake(0, 0) inView:main_view];

    recognizer.view.center=CGPointMake(recognizer.view.center.x+translation1.x, recognizer.view.center.y+ translation1.y);
}

-(void)move:(UIPanGestureRecognizer*)recognizer
{
    if ([recognizer state] == UIGestureRecognizerStateChanged)    
    {
        CGPoint translation = [recognizer translationInView:self.view];
        recognizer.view.center=CGPointMake(recognizer.view.center.x+translation.x, recognizer.view.center.y+ translation.y);
        [recognizer setTranslation:CGPointMake(0, 0) inView:self.view];
    }
}

How to set my phpmyadmin user session to not time out so quickly?

Once you're logged into phpmyadmin look on the top navigation for "Settings" and click that then:

"Features" >

...and you'll find "Login cookie validity" which is typically set to 1440.

Unfortunately changing it through the UI means that the changes don't persist between logins.

How to hide a navigation bar from first ViewController in Swift?

You can unhide navigationController in viewWillDisappear

override func viewWillDisappear(animated: Bool)
{
    super.viewWillDisappear(animated)
    self.navigationController?.isNavigationBarHidden = false
}

Swift 3

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)

    self.navigationController?.setNavigationBarHidden(false, animated: animated)
}

How to make rectangular image appear circular with CSS

<html>
    <head>
<script src="//code.jquery.com/jquery-1.11.0.min.js"></script>
    <style>
    .round_img {
    border-radius: 50%;
    max-width: 150px;
    border: 1px solid #ccc;
    }
    </style>
    <script>
    var cw = $('.round_img').width();
    $('.round_img').css({
    'height': cw + 'px'
    });
    </script>
    </head>
    <body>
    <img class="round_img" src="image.jpg" alt="" title="" />
    </body>
</html>

http://jsfiddle.net/suryakiran/1xqs4ztc/

enable/disable zoom in Android WebView

We had the same problem while working on an Android application for a customer and I managed to "hack" around this restriction.

I took a look at the Android Source code for the WebView class and spotted a updateZoomButtonsEnabled()-method which was working with an ZoomButtonsController-object to enable and disable the zoom controls depending on the current scale of the browser.

I searched for a method to return the ZoomButtonsController-instance and found the getZoomButtonsController()-method, that returned this very instance.

Although the method is declared public, it is not documented in the WebView-documentation and Eclipse couldn't find it either. So, I tried some reflection on that and created my own WebView-subclass to override the onTouchEvent()-method, which triggered the controls.

public class NoZoomControllWebView extends WebView {

    private ZoomButtonsController zoom_controll = null;

    public NoZoomControllWebView(Context context) {
        super(context);
        disableControls();
    }

    public NoZoomControllWebView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        disableControls();
    }

    public NoZoomControllWebView(Context context, AttributeSet attrs) {
        super(context, attrs);
        disableControls();
    }

    /**
     * Disable the controls
     */
    private void disableControls(){
        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.HONEYCOMB) {
            // Use the API 11+ calls to disable the controls
            this.getSettings().setBuiltInZoomControls(true);
            this.getSettings().setDisplayZoomControls(false);
        } else {
            // Use the reflection magic to make it work on earlier APIs
            getControlls();
        }
    }

    /**
     * This is where the magic happens :D
     */
    private void getControlls() {
        try {
            Class webview = Class.forName("android.webkit.WebView");
            Method method = webview.getMethod("getZoomButtonsController");
            zoom_controll = (ZoomButtonsController) method.invoke(this, null);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        super.onTouchEvent(ev);
        if (zoom_controll != null){
            // Hide the controlls AFTER they where made visible by the default implementation.
            zoom_controll.setVisible(false);
        }
        return true;
    }
}

You might want to remove the unnecessary constructors and react on probably on the exceptions.

Although this looks hacky and unreliable, it works back to API Level 4 (Android 1.6).


As @jayellos pointed out in the comments, the private getZoomButtonsController()-method is no longer existing on Android 4.0.4 and later.

However, it doesn't need to. Using conditional execution, we can check if we're on a device with API Level 11+ and use the exposed functionality (see @Yuttadhammo answer) to hide the controls.

I updated the example code above to do exactly that.

SQLSTATE[HY000] [1045] Access denied for user 'root'@'localhost' (using password: YES) symfony2

write direct password into config>database.php

'password' => env('DB_PASSWORD', '')

Change to

'password' => 'your password',

C linked list inserting node at the end

This code will work. The answer from samplebias is almost correct, but you need a third change:

int addNodeBottom(int val, node *head){

    //create new node
    node *newNode = (node*)malloc(sizeof(node));

    if(newNode == NULL){
        fprintf(stderr, "Unable to allocate memory for new node\n");
        exit(-1);
    }

    newNode->value = val;
    newNode->next = NULL;  // Change 1

    //check for first insertion
    if(head->next == NULL){
        head->next = newNode;
        printf("added at beginning\n");
    }

    else
    {
        //else loop through the list and find the last
        //node, insert next to it
        node *current = head;
        while (true) { // Change 2
            if(current->next == NULL)
            {
                current->next = newNode;
                printf("added later\n");
                break; // Change 3
            }
            current = current->next;
        };
    }
    return 0;
}

Change 1: newNode->next must be set to NULL so we don't insert invalid pointers at the end of the list.

Change 2/3: The loop is changed to an endless loop that will be jumped out with break; when we found the last element. Note how while(current->next != NULL) contradicted if(current->next == NULL) before.

EDIT: Regarding the while loop, this way it is much better:

  node *current = head;
  while (current->next != NULL) {
    current = current->next;
  }
  current->next = newNode;
  printf("added later\n");

var.replace is not a function

My guess is that the code that's calling your trim function is not actually passing a string to it.

To fix this, you can make str a string, like this: str.toString().replace(...)
...as alper pointed out below.

Mercurial: how to amend the last commit?

You have 3 options to edit commits in Mercurial:

  1. hg strip --keep --rev -1 undo the last (1) commit(s), so you can do it again (see this answer for more information).

  2. Using the MQ extension, which is shipped with Mercurial

  3. Even if it isn't shipped with Mercurial, the Histedit extension is worth mentioning

You can also have a look on the Editing History page of the Mercurial wiki.

In short, editing history is really hard and discouraged. And if you've already pushed your changes, there's barely nothing you can do, except if you have total control of all the other clones.

I'm not really familiar with the git commit --amend command, but AFAIK, Histedit is what seems to be the closest approach, but sadly it isn't shipped with Mercurial. MQ is really complicated to use, but you can do nearly anything with it.

PHP Notice: Undefined offset: 1 with array when reading data

The ideal solution would be as below. You won't miss the values from 0 to n.

$len=count($data);
for($i=0;$i<$len;$i++)
     echo $data[$i]. "<br>";

DBCC CHECKIDENT Sets Identity to 0

As you pointed out in your question it is a documented behavior. I still find it strange though. I use to repopulate the test database and even though I do not rely on the values of identity fields it was a bit of annoying to have different values when populating the database for the first time from scratch and after removing all data and populating again.

A possible solution is to use truncate to clean the table instead of delete. But then you need to drop all the constraints and recreate them afterwards

In that way it always behaves as a newly created table and there is no need to call DBCC CHECKIDENT. The first identity value will be the one specified in the table definition and it will be the same no matter if you insert the data for the first time or for the N-th

When to use references vs. pointers

Just putting my dime in. I just performed a test. A sneeky one at that. I just let g++ create the assembly files of the same mini-program using pointers compared to using references. When looking at the output they are exactly the same. Other than the symbolnaming. So looking at performance (in a simple example) there is no issue.

Now on the topic of pointers vs references. IMHO I think clearity stands above all. As soon as I read implicit behaviour my toes start to curl. I agree that it is nice implicit behaviour that a reference cannot be NULL.

Dereferencing a NULL pointer is not the problem. it will crash your application and will be easy to debug. A bigger problem is uninitialized pointers containing invalid values. This will most likely result in memory corruption causing undefined behaviour without a clear origin.

This is where I think references are much safer than pointers. And I agree with a previous statement, that the interface (which should be clearly documented, see design by contract, Bertrand Meyer) defines the result of the parameters to a function. Now taking this all into consideration my preferences go to using references wherever/whenever possible.

How to execute Python code from within Visual Studio Code

To extend vlad2135's answer (read his first); that is how you set up Python debugging in Visual Studio Code with Don Jayamanne's great Python extension (which is a pretty full featured IDE for Python these days, and arguably one of Visual Studio Code's best language extensions, IMO).

Basically, when you click the gear icon, it creates a launch.json file in your .vscode directory in your workspace. You can also make this yourself, but it's probably just simpler to let Visual Studio Code do the heavy lifting. Here's an example file:

File launch.json

You'll notice something cool after you generate it. It automatically created a bunch of configurations (most of mine are cut off; just scroll to see them all) with different settings and extra features for different libraries or environments (like Django).

The one you'll probably end up using the most is Python; which is a plain (in my case C)Python debugger and is easiest to work with settings wise.

I'll make a short walkthrough of the JSON attributes for this one, since the others use the pretty much same configuration with only different interpreter paths and one or two different other features there.

  • name: The name of the configuration. A useful example of why you would change it is if you have two Python configurations which use the same type of config, but different arguments. It's what shows up in the box you see on the top left (my box says "python" since I'm using the default Python configuration).
  • type: Interpreter type. You generally don't want to change this one.
  • request: How you want to run your code, and you generally don't want to change this one either. Default value is "launch", but changing it to "attach" allows the debugger to attach to an already running Python process. Instead of changing it, add a configuration of type attach and use that.
  • stopOnEntry: Python debuggers like to have an invisible break-point when you start the program so you can see the entry-point file and where your first line of active code is. It drives some C#/Java programmers like me insane. false if you don't want it, true otherwise.
  • pythonPath: The path to your install of Python. The default value gets the extension level default in the user/workspace settings. Change it here if you want to have different Pythons for different debug processes. Change it in workspace settings if you want to change it for all debug processes set to the default configuration in a project. Change it in user setting to change where the extension finds Pythons across all projects. (4/12/2017 The following was fixed in extension version 0.6.1). Ironically enough, this gets auto-generated wrong. It auto-generates to "${config.python.pythonPath}" which is deprecated in the newer Visual Studio Code versions. It might still work, but you should use "${config:python.pythonPath}" instead for your default first python on your path or Visual Studio Code settings. (4/6/2017 Edit: This should be fixed in the next release. The team committed the fix a few days ago.)
  • program: The initial file that you debugger starts up when you hit run. "${workspaceRoot}" is the root folder you opened up as your workspace (When you go over to the file icon, the base open folder). Another neat trick if you want to get your program running quickly, or you have multiple entry points to your program is to set this to "${file}" which will start debugging at the file you have open and in focus in the moment you hit debug.
  • cwd: The current working directory folder of the project you're running. Usually you'll just want to leave this "${workspaceRoot}".
  • debugOptions: Some debugger flags. The ones in the picture are default flags, you can find more flags in the python debugger pages, I'm sure.
  • args: This isn't actually a default configuration setting, but a useful one nonetheless (and probably what the OP was asking about). These are the command line arguments that you pass in to your program. The debugger passes these in as though they you had typed: python file.py [args] into your terminal; passing each JSON string in the list to the program in order.

You can go here for more information on the Visual Studio Code file variables you can use to configure your debuggers and paths.

You can go here for the extension's own documentation on launch options, with both optional and required attributes.

You can click the Add Configuration button at the bottom right if you don't see the config template already in the file. It'll give you a list to auto generate a configuration for most of the common debug processes out there.

Now, as per vlad's answer, you may add any breakpoints you need as per normal visual debuggers, choose which run configuration you want in the top left dropdown menu and you can tap the green arrow to the left to the configuration name to start your program.

Pro tip: Different people on your team use different IDEs and they probably don't need your configuration files. Visual Studio Code nearly always puts it's IDE files in one place (by design for this purpose; I assume), launch or otherwise so make sure to add directory .vscode/ to your .gitignore if this is your first time generating a Visual Studio Code file (this process will create the folder in your workspace if you don't have it already)!

Multiple Forms or Multiple Submits in a Page?

Best practice: one form per product is definitely the way to go.

Benefits:

  • It will save you the hassle of having to parse the data to figure out which product was clicked
  • It will reduce the size of data being posted

In your specific situation

If you only ever intend to have one form element, in this case a submit button, one form for all should work just fine.


My recommendation Do one form per product, and change your markup to something like:

<form method="post" action="">
    <input type="hidden" name="product_id" value="123">
    <button type="submit" name="action" value="add_to_cart">Add to Cart</button>
</form>

This will give you a much cleaner and usable POST. No parsing. And it will allow you to add more parameters in the future (size, color, quantity, etc).

Note: There's no technical benefit to using <button> vs. <input>, but as a programmer I find it cooler to work with action=='add_to_cart' than action=='Add to Cart'. Besides, I hate mixing presentation with logic. If one day you decide that it makes more sense for the button to say "Add" or if you want to use different languages, you could do so freely without having to worry about your back-end code.

Elevating process privilege programmatically?

According to the article Chris Corio: Teach Your Apps To Play Nicely With Windows Vista User Account Control, MSDN Magazine, Jan. 2007, only ShellExecute checks the embedded manifest and prompts the user for elevation if needed, while CreateProcess and other APIs don't. Hope it helps.

See also: same article as .chm.

Watching variables in SSIS during debug

Drag the variable from Variables pane to Watch pane and voila!

Excel Validation Drop Down list using VBA

Private Sub main()

'replace "J2" with the cell you want to insert the drop down list
With Range("J2").Validation
    .Delete
    'replace "=A1:A6" with the range the data is in.
    .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, _
    Operator:=xlBetween, Formula1:="=Sheet1!A1:A6"
    .IgnoreBlank = True
    .InCellDropdown = True
    .InputTitle = ""
    .ErrorTitle = ""
    .InputMessage = ""
    .ErrorMessage = ""
    .ShowInput = True
    .ShowError = True
End With
End Sub

Escape double quotes in Java

For a String constant you have no choice other than escaping via backslash.

Maybe you find the MyBatis project interesting. It is a thin layer over JDBC where you can externalize your SQL queries in XML configuration files without the need to escape double quotes.

Deep copy of a dict in python

I like and learned a lot from Lasse V. Karlsen. I modified it into the following example, which highlights pretty well the difference between shallow dictionary copies and deep copies:

    import copy

    my_dict = {'a': [1, 2, 3], 'b': [4, 5, 6]}
    my_copy = copy.copy(my_dict)
    my_deepcopy = copy.deepcopy(my_dict)

Now if you change

    my_dict['a'][2] = 7

and do

    print("my_copy a[2]: ",my_copy['a'][2],",whereas my_deepcopy a[2]: ", my_deepcopy['a'][2])

you get

    >> my_copy a[2]:  7 ,whereas my_deepcopy a[2]:  3

Difference between VARCHAR and TEXT in MySQL

There is an important detail that has been omitted in the answer above.

MySQL imposes a limit of 65,535 bytes for the max size of each row. The size of a VARCHAR column is counted towards the maximum row size, while TEXT columns are assumed to be storing their data by reference so they only need 9-12 bytes. That means even if the "theoretical" max size of your VARCHAR field is 65,535 characters you won't be able to achieve that if you have more than one column in your table.

Also note that the actual number of bytes required by a VARCHAR field is dependent on the encoding of the column (and the content). MySQL counts the maximum possible bytes used toward the max row size, so if you use a multibyte encoding like utf8mb4 (which you almost certainly should) it will use up even more of your maximum row size.

Correction: Regardless of how MySQL computes the max row size, whether or not the VARCHAR/TEXT field data is ACTUALLY stored in the row or stored by reference depends on your underlying storage engine. For InnoDB the row format affects this behavior. (Thanks Bill-Karwin)

Reasons to use TEXT:

  • If you want to store a paragraph or more of text
  • If you don't need to index the column
  • If you have reached the row size limit for your table

Reasons to use VARCHAR:

  • If you want to store a few words or a sentence
  • If you want to index the (entire) column
  • If you want to use the column with foreign-key constraints

Sanitizing user input before adding it to the DOM in Javascript

Never use escape(). It's nothing to do with HTML-encoding. It's more like URL-encoding, but it's not even properly that. It's a bizarre non-standard encoding available only in JavaScript.

If you want an HTML encoder, you'll have to write it yourself as JavaScript doesn't give you one. For example:

function encodeHTML(s) {
    return s.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/"/g, '&quot;');
}

However whilst this is enough to put your user_id in places like the input value, it's not enough for id because IDs can only use a limited selection of characters. (And % isn't among them, so escape() or even encodeURIComponent() is no good.)

You could invent your own encoding scheme to put any characters in an ID, for example:

function encodeID(s) {
    if (s==='') return '_';
    return s.replace(/[^a-zA-Z0-9.-]/g, function(match) {
        return '_'+match[0].charCodeAt(0).toString(16)+'_';
    });
}

But you've still got a problem if the same user_id occurs twice. And to be honest, the whole thing with throwing around HTML strings is usually a bad idea. Use DOM methods instead, and retain JavaScript references to each element, so you don't have to keep calling getElementById, or worrying about how arbitrary strings are inserted into IDs.

eg.:

function addChut(user_id) {
    var log= document.createElement('div');
    log.className= 'log';
    var textarea= document.createElement('textarea');
    var input= document.createElement('input');
    input.value= user_id;
    input.readonly= True;
    var button= document.createElement('input');
    button.type= 'button';
    button.value= 'Message';

    var chut= document.createElement('div');
    chut.className= 'chut';
    chut.appendChild(log);
    chut.appendChild(textarea);
    chut.appendChild(input);
    chut.appendChild(button);
    document.getElementById('chuts').appendChild(chut);

    button.onclick= function() {
        alert('Send '+textarea.value+' to '+user_id);
    };

    return chut;
}

You could also use a convenience function or JS framework to cut down on the lengthiness of the create-set-appends calls there.

ETA:

I'm using jQuery at the moment as a framework

OK, then consider the jQuery 1.4 creation shortcuts, eg.:

var log= $('<div>', {className: 'log'});
var input= $('<input>', {readOnly: true, val: user_id});
...

The problem I have right now is that I use JSONP to add elements and events to a page, and so I can not know whether the elements already exist or not before showing a message.

You can keep a lookup of user_id to element nodes (or wrapper objects) in JavaScript, to save putting that information in the DOM itself, where the characters that can go in an id are restricted.

var chut_lookup= {};
...

function getChut(user_id) {
    var key= '_map_'+user_id;
    if (key in chut_lookup)
        return chut_lookup[key];
    return chut_lookup[key]= addChut(user_id);
}

(The _map_ prefix is because JavaScript objects don't quite work as a mapping of arbitrary strings. The empty string and, in IE, some Object member names, confuse it.)

Disable password authentication for SSH

Here's a script to do this automatically

# Only allow key based logins
sed -n 'H;${x;s/\#PasswordAuthentication yes/PasswordAuthentication no/;p;}' /etc/ssh/sshd_config > tmp_sshd_config
cat tmp_sshd_config > /etc/ssh/sshd_config
rm tmp_sshd_config

Python URLLib / URLLib2 POST

u = urllib2.urlopen('http://myserver/inout-tracker', data)
h.request('POST', '/inout-tracker/index.php', data, headers)

Using the path /inout-tracker without a trailing / doesn't fetch index.php. Instead the server will issue a 302 redirect to the version with the trailing /.

Doing a 302 will typically cause clients to convert a POST to a GET request.

App.Config Transformation for projects which are not Web Projects in Visual Studio?

I wrote nice extension to automate app.config transformation like the one built in Web Application Project Configuration Transform

The biggest advantage of this extension is that you don’t need to install it on all build machines

Using comma as list separator with AngularJS

Also:

angular.module('App.filters', [])
    .filter('joinBy', function () {
        return function (input,delimiter) {
            return (input || []).join(delimiter || ',');
        };
    });

And in template:

{{ itemsArray | joinBy:',' }}

Google Play Services GCM 9.2.0 asks to "update" back to 9.0.0

Do you have the line

apply plugin: 'com.google.gms.google-services' 

line at the bottom of your app's build.gradle file?

I saw some errors when it was on the top and as it's written here, it should be at the bottom.

How to make the division of 2 ints produce a float instead of another int?

Cast one of the integers/both of the integer to float to force the operation to be done with floating point Math. Otherwise integer Math is always preferred. So:

1. v = (float)s / t;
2. v = (float)s / (float)t;

How to build a RESTful API?

As simon marc said, the process is much the same as it is for you or I browsing a website. If you are comfortable with using the Zend framework, there are some easy to follow tutorials to that make life quite easy to set things up. The hardest part of building a restful api is the design of the it, and making it truly restful, think CRUD in database terms.

It could be that you really want an xmlrpc interface or something else similar. What do you want this interface to allow you to do?

--EDIT

Here is where I got started with restful api and Zend Framework. Zend Framework Example

In short don't use Zend rest server, it's obsolete.

Responsive dropdown navbar with angular-ui bootstrap (done in the correct angular kind of way)

Update 2015-06

Based on antoinepairet's comment/example:

Using uib-collapse attribute provides animations: http://plnkr.co/edit/omyoOxYnCdWJP8ANmTc6?p=preview

<nav class="navbar navbar-default" role="navigation">
    <div class="navbar-header">

        <!-- note the ng-init and ng-click here: -->
        <button type="button" class="navbar-toggle" ng-init="navCollapsed = true" ng-click="navCollapsed = !navCollapsed">
            <span class="sr-only">Toggle navigation</span>
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
        </button>
        <a class="navbar-brand" href="#">Brand</a>
    </div>

    <div class="collapse navbar-collapse" uib-collapse="navCollapsed">
        <ul class="nav navbar-nav">
        ...
        </ul>
    </div>
</nav>

Ancient..

I see that the question is framed around BS2, but I thought I'd pitch in with a solution for Bootstrap 3 using ng-class solution based on suggestions in ui.bootstrap issue 394:

The only variation from the official bootstrap example is the addition of ng- attributes noted by comments, below:

<nav class="navbar navbar-default" role="navigation">
  <div class="navbar-header">

    <!-- note the ng-init and ng-click here: -->
    <button type="button" class="navbar-toggle" ng-init="navCollapsed = true" ng-click="navCollapsed = !navCollapsed">
      <span class="sr-only">Toggle navigation</span>
      <span class="icon-bar"></span>
      <span class="icon-bar"></span>
      <span class="icon-bar"></span>
    </button>
    <a class="navbar-brand" href="#">Brand</a>
  </div>

  <!-- note the ng-class here -->
  <div class="collapse navbar-collapse" ng-class="{'in':!navCollapsed}">

    <ul class="nav navbar-nav">
    ...

Here is an updated working example: http://plnkr.co/edit/OlCCnbGlYWeO7Nxwfj5G?p=preview (hat tip Lars)

This seems to works for me in simple use cases, but you'll note in the example that the second dropdown is cut off… good luck!

How can I check the size of a collection within a Django template?

I need the collection length to decide whether I should render table <thead></thead>

but don't know why @Django 2.1.7 the chosen answer will fail(empty) my forloop afterward.

I got to use {% if forloop.first %} {% endif %} to overcome:

<table>
    {% for record in service_list %}
        {% if forloop.first %}
            <thead>
            <tr>
                <th>??</th>
            </tr>
            </thead>
        {% endif %}
        <tbody>
        <tr>
            <td>{{ record.date }}</td>
        </tr>
    {% endfor %}
    </tbody>
</table>

How to filter an array from all elements of another array

_x000D_
_x000D_
        /* Here's an example that uses (some) ES6 Javascript semantics to filter an object array by another object array. */_x000D_
_x000D_
        // x = full dataset_x000D_
        // y = filter dataset_x000D_
        let x = [_x000D_
            {"val": 1, "text": "a"},_x000D_
            {"val": 2, "text": "b"},_x000D_
            {"val": 3, "text": "c"},_x000D_
            {"val": 4, "text": "d"},_x000D_
            {"val": 5, "text": "e"}_x000D_
            ],_x000D_
            y = [_x000D_
            {"val": 1, "text": "a"},_x000D_
            {"val": 4, "text": "d"}               _x000D_
            ];_x000D_
_x000D_
        // Use map to get a simple array of "val" values. Ex: [1,4]_x000D_
        let yFilter = y.map(itemY => { return itemY.val; });_x000D_
_x000D_
        // Use filter and "not" includes to filter the full dataset by the filter dataset's val._x000D_
        let filteredX = x.filter(itemX => !yFilter.includes(itemX.val));_x000D_
_x000D_
        // Print the result._x000D_
        console.log(filteredX);
_x000D_
_x000D_
_x000D_

Do you use source control for your database items?

Yes, we source control our sql scripts too with subversion. It's a good practice and you can recreate the schema with default data whenever needed.

Syncing Android Studio project with Gradle files

Old Answer

When trying to run the application, instead of selecting the directory highlighted here in blueenter image description here

I selected the subdirectory instead

enter image description here

and clicked "run".All the issues with Gradle are automatically resolved and the missing apk directory is automatically created.

New Solution

The Sync project with gradle files button disappeared from Android Studio for a while.Its back and you can find it here:

enter image description here

hit the button and wait for the task to complete

How to get text of an input text box during onKeyPress?

Try to concatenate the event charCode to the value you get. Here is a sample of my code:

<input type="text" name="price" onkeypress="return (cnum(event,this))" maxlength="10">
<p id="demo"></p>

js:

function cnum(event, str) {
    var a = event.charCode;
    var ab = str.value + String.fromCharCode(a);
    document.getElementById('demo').innerHTML = ab;
}

The value in ab will get the latest value in the input field.

Google Map API v3 — set bounds and center

Got everything sorted - see the last few lines for code - (bounds.extend(myLatLng); map.fitBounds(bounds);)

function initialize() {
  var myOptions = {
    zoom: 10,
    center: new google.maps.LatLng(0, 0),
    mapTypeId: google.maps.MapTypeId.ROADMAP
  }
  var map = new google.maps.Map(
    document.getElementById("map_canvas"),
    myOptions);
  setMarkers(map, beaches);
}

var beaches = [
  ['Bondi Beach', -33.890542, 151.274856, 4],
  ['Coogee Beach', -33.923036, 161.259052, 5],
  ['Cronulla Beach', -36.028249, 153.157507, 3],
  ['Manly Beach', -31.80010128657071, 151.38747820854187, 2],
  ['Maroubra Beach', -33.950198, 151.159302, 1]
];

function setMarkers(map, locations) {
  var image = new google.maps.MarkerImage('images/beachflag.png',
    new google.maps.Size(20, 32),
    new google.maps.Point(0,0),
    new google.maps.Point(0, 32));
  var shadow = new google.maps.MarkerImage('images/beachflag_shadow.png',
    new google.maps.Size(37, 32),
    new google.maps.Point(0,0),
    new google.maps.Point(0, 32));
  var shape = {
    coord: [1, 1, 1, 20, 18, 20, 18 , 1],
    type: 'poly'
  };
  var bounds = new google.maps.LatLngBounds();
  for (var i = 0; i < locations.length; i++) {
    var beach = locations[i];
    var myLatLng = new google.maps.LatLng(beach[1], beach[2]);
    var marker = new google.maps.Marker({
      position: myLatLng,
      map: map,
      shadow: shadow,
      icon: image,
      shape: shape,
      title: beach[0],
      zIndex: beach[3]
    });
    bounds.extend(myLatLng);
  }
  map.fitBounds(bounds);
}

Ruby on Rails: How do I add placeholder text to a f.text_field?

For those using Rails(4.2) Internationalization (I18n):

Set the placeholder attribute to true:

f.text_field :attr, placeholder: true

and in your local file (ie. en.yml):

en:
  helpers:
    placeholder:
      model_name:
        attr: "some placeholder text"

How to change HTML Object element data attribute value in javascript

In JavaScript, you can assign values to data attributes through Element.dataset.

For example:

avatar.dataset.id = 12345;

Reference: https://developer.mozilla.org/en/docs/Web/API/HTMLElement/dataset

Installing python module within code

This should work:

import subprocess

def install(name):
    subprocess.call(['pip', 'install', name])

Attach parameter to button.addTarget action in Swift

You cannot pass custom parameters in addTarget:.One alternative is set the tag property of button and do work based on the tag.

button.tag = 5
button.addTarget(self, action: "buttonClicked:", 
    forControlEvents: UIControlEvents.TouchUpInside)

Or for Swift 2.2 and greater:

button.tag = 5
button.addTarget(self,action:#selector(buttonClicked),
    forControlEvents:.TouchUpInside)

Now do logic based on tag property

@objc func buttonClicked(sender:UIButton)
{
    if(sender.tag == 5){

        var abc = "argOne" //Do something for tag 5
    }
    print("hello")
}

How to convert an array into an object using stdClass()

If you want to recursively convert the entire array into an Object type (stdClass) then , below is the best method and it's not time-consuming or memory deficient especially when you want to do a recursive (multi-level) conversion compared to writing your own function.

$array_object = json_decode(json_encode($array));

How to get highcharts dates in the x axis?

Highcharts will automatically try to find the best format for the current zoom-range. This is done if the xAxis has the type 'datetime'. Next the unit of the current zoom is calculated, it could be one of:

  • second
  • minute
  • hour
  • day
  • week
  • month
  • year

This unit is then used find a format for the axis labels. The default patterns are:

second: '%H:%M:%S',
minute: '%H:%M',
hour: '%H:%M',
day: '%e. %b',
week: '%e. %b',
month: '%b \'%y',
year: '%Y'

If you want the day to be part of the "hour"-level labels you should change the dateTimeLabelFormats option for that level include %d or %e. These are the available patters:

  • %a: Short weekday, like 'Mon'.
  • %A: Long weekday, like 'Monday'.
  • %d: Two digit day of the month, 01 to 31.
  • %e: Day of the month, 1 through 31.
  • %b: Short month, like 'Jan'.
  • %B: Long month, like 'January'.
  • %m: Two digit month number, 01 through 12.
  • %y: Two digits year, like 09 for 2009.
  • %Y: Four digits year, like 2009.
  • %H: Two digits hours in 24h format, 00 through 23.
  • %I: Two digits hours in 12h format, 00 through 11.
  • %l (Lower case L): Hours in 12h format, 1 through 11.
  • %M: Two digits minutes, 00 through 59.
  • %p: Upper case AM or PM.
  • %P: Lower case AM or PM.
  • %S: Two digits seconds, 00 through 59

http://api.highcharts.com/highcharts#xAxis.dateTimeLabelFormats

Maven Installation OSX Error Unsupported major.minor version 51.0

Please rather try:

$JAVA_HOME/bin/java -version

Maven uses $JAVA_HOME for classpath resolution of JRE libs. To be sure to use a certain JDK, set it explicitly before compiling, for example:

export JAVA_HOME=/usr/java/jdk1.7.0_51

Isn't there a version < 1.7 and you're using Maven 3.3.1? In this case the reason is a new prerequisite: https://issues.apache.org/jira/browse/MNG-5780

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

It can't be stated enough that you can use console.debug(object) for this. This technique will save you literally hundreds of hours a year if you do this for a living :p

Converting double to string with N decimals, dot as decimal separator, and no thousand separator

I prefer to use ToString() and IFormatProvider.

double value = 100000.3
Console.WriteLine(value.ToString("0,0.00", new CultureInfo("en-US", false)));

Output: 10,000.30

How to set UTF-8 encoding for a PHP file

Also note that setting a header to "text/plain" will result in all html and php (in part) printing the characters on the screen as TEXT, not as HTML. So be aware of possible HTML not parsing when using text type plain.

Using:

header('Content-type: text/html; charset=utf-8');

Can return HTML and PHP as well. Not just text.

How do I write a compareTo method which compares objects?

The compareTo method is described as follows:

Compares this object with the specified object for order. Returns a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.

Let's say we would like to compare Jedis by their age:

class Jedi implements Comparable<Jedi> {

    private final String name;
    private final int age;
        //...
}

Then if our Jedi is older than the provided one, you must return a positive, if they are the same age, you return 0, and if our Jedi is younger you return a negative.

public int compareTo(Jedi jedi){
    return this.age > jedi.age ? 1 : this.age < jedi.age ? -1 : 0;
}

By implementing the compareTo method (coming from the Comparable interface) your are defining what is called a natural order. All sorting methods in JDK will use this ordering by default.

There are ocassions in which you may want to base your comparision in other objects, and not on a primitive type. For instance, copare Jedis based on their names. In this case, if the objects being compared already implement Comparable then you can do the comparison using its compareTo method.

public int compareTo(Jedi jedi){
    return this.name.compareTo(jedi.getName());
}

It would be simpler in this case.

Now, if you inted to use both name and age as the comparison criteria then you have to decide your oder of comparison, what has precedence. For instance, if two Jedis are named the same, then you can use their age to decide which goes first and which goes second.

public int compareTo(Jedi jedi){
    int result = this.name.compareTo(jedi.getName());
    if(result == 0){
        result = this.age > jedi.age ? 1 : this.age < jedi.age ? -1 : 0;
    }
    return result;
}

If you had an array of Jedis

Jedi[] jediAcademy = {new Jedi("Obiwan",80), new Jedi("Anakin", 30), ..}

All you have to do is to ask to the class java.util.Arrays to use its sort method.

Arrays.sort(jediAcademy);

This Arrays.sort method will use your compareTo method to sort the objects one by one.

Get the directory from a file path in java (android)

A better way, use getParent() from File Class..

String a="/root/sdcard/Pictures/img0001.jpg"; // A valid file path 
File file = new File(a); 
String getDirectoryPath = file.getParent(); // Only return path if physical file exist else return null

http://developer.android.com/reference/java/io/File.html#getParent%28%29

Paging UICollectionView by cells, not screen

Here's the easiest way that i found to do that in Swift 4.2 for horinzontal scroll:

I'm using the first cell on visibleCells and scrolling to then, if the first visible cell are showing less of the half of it's width i'm scrolling to the next one.

If your collection scroll vertically, simply change x by y and width by height

func scrollViewWillEndDragging(_ scrollView: UIScrollView, withVelocity velocity: CGPoint, targetContentOffset: UnsafeMutablePointer<CGPoint>) {
    targetContentOffset.pointee = scrollView.contentOffset
    var indexes = self.collectionView.indexPathsForVisibleItems
    indexes.sort()
    var index = indexes.first!
    let cell = self.collectionView.cellForItem(at: index)!
    let position = self.collectionView.contentOffset.x - cell.frame.origin.x
    if position > cell.frame.size.width/2{
       index.row = index.row+1
    }
    self.collectionView.scrollToItem(at: index, at: .left, animated: true )
}

How to spawn a process and capture its STDOUT in .NET?

Here's code that I've verified to work. I use it for spawning MSBuild and listening to its output:

process.StartInfo.UseShellExecute = false;
process.StartInfo.RedirectStandardOutput = true;
process.OutputDataReceived += (sender, args) => Console.WriteLine("received output: {0}", args.Data);
process.Start();
process.BeginOutputReadLine();

How to merge two PDF files into one in Java?

This is a ready to use code, merging four pdf files with itext.jar from http://central.maven.org/maven2/com/itextpdf/itextpdf/5.5.0/itextpdf-5.5.0.jar, more on http://tutorialspointexamples.com/

import com.itextpdf.text.Document;
import com.itextpdf.text.pdf.PdfContentByte;
import com.itextpdf.text.pdf.PdfImportedPage;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfWriter;

/**
 * This class is used to merge two or more 
 * existing pdf file using iText jar.
 */
public class PDFMerger {

static void mergePdfFiles(List<InputStream> inputPdfList,
        OutputStream outputStream) throws Exception{
    //Create document and pdfReader objects.
    Document document = new Document();
    List<PdfReader> readers = 
            new ArrayList<PdfReader>();
    int totalPages = 0;

    //Create pdf Iterator object using inputPdfList.
    Iterator<InputStream> pdfIterator = 
            inputPdfList.iterator();

    // Create reader list for the input pdf files.
    while (pdfIterator.hasNext()) {
            InputStream pdf = pdfIterator.next();
            PdfReader pdfReader = new PdfReader(pdf);
            readers.add(pdfReader);
            totalPages = totalPages + pdfReader.getNumberOfPages();
    }

    // Create writer for the outputStream
    PdfWriter writer = PdfWriter.getInstance(document, outputStream);

    //Open document.
    document.open();

    //Contain the pdf data.
    PdfContentByte pageContentByte = writer.getDirectContent();

    PdfImportedPage pdfImportedPage;
    int currentPdfReaderPage = 1;
    Iterator<PdfReader> iteratorPDFReader = readers.iterator();

    // Iterate and process the reader list.
    while (iteratorPDFReader.hasNext()) {
            PdfReader pdfReader = iteratorPDFReader.next();
            //Create page and add content.
            while (currentPdfReaderPage <= pdfReader.getNumberOfPages()) {
                  document.newPage();
                  pdfImportedPage = writer.getImportedPage(
                          pdfReader,currentPdfReaderPage);
                  pageContentByte.addTemplate(pdfImportedPage, 0, 0);
                  currentPdfReaderPage++;
            }
            currentPdfReaderPage = 1;
    }

    //Close document and outputStream.
    outputStream.flush();
    document.close();
    outputStream.close();

    System.out.println("Pdf files merged successfully.");
}

public static void main(String args[]){
    try {
        //Prepare input pdf file list as list of input stream.
        List<InputStream> inputPdfList = new ArrayList<InputStream>();
        inputPdfList.add(new FileInputStream("..\\pdf\\pdf_1.pdf"));
        inputPdfList.add(new FileInputStream("..\\pdf\\pdf_2.pdf"));
        inputPdfList.add(new FileInputStream("..\\pdf\\pdf_3.pdf"));
        inputPdfList.add(new FileInputStream("..\\pdf\\pdf_4.pdf"));


        //Prepare output stream for merged pdf file.
        OutputStream outputStream = 
                new FileOutputStream("..\\pdf\\MergeFile_1234.pdf");

        //call method to merge pdf files.
        mergePdfFiles(inputPdfList, outputStream);     
    } catch (Exception e) {
        e.printStackTrace();
    }
    }
}

ldap_bind: Invalid Credentials (49)

I don't see an obvious problem with the above.

It's possible your ldap.conf is being overridden, but the command-line options will take precedence, ldapsearch will ignore BINDDN in the main ldap.conf, so the only parameter that could be wrong is the URI. (The order is ETCDIR/ldap.conf then ~/ldaprc or ~/.ldaprc and then ldaprc in the current directory, though there environment variables which can influence this too, see man ldapconf.)

Try an explicit URI:

ldapsearch -x -W -D 'cn=Manager,dc=example,dc=com' -b "" -s base -H ldap://localhost

or prevent defaults with:

LDAPNOINIT=1 ldapsearch -x -W -D 'cn=Manager,dc=example,dc=com' -b "" -s base

If that doesn't work, then some troubleshooting (you'll probably need the full path to the slapd binary for these):

  • make sure your slapd.conf is being used and is correct (as root)

    slapd -T test -f slapd.conf -d 65535

    You may have a left-over or default slapd.d configuration directory which takes preference over your slapd.conf (unless you specify your config explicitly with -f, slapd.conf is officially deprecated in OpenLDAP-2.4). If you don't get several pages of output then your binaries were built without debug support.

  • stop OpenLDAP, then manually start slapd in a separate terminal/console with debug enabled (as root, ^C to quit)

    slapd -h ldap://localhost -d 481

    then retry the search and see if you can spot the problem (there will be a lot of schema noise in the start of the output unfortunately). (Note: running slapd without the -u/-g options can change file ownerships which can cause problems, you should usually use those options, probably -u ldap -g ldap )

  • if debug is enabled, then try also

    ldapsearch -v -d 63 -W -D 'cn=Manager,dc=example,dc=com' -b "" -s base

MVC Form not able to post List of objects

Please read this: http://haacked.com/archive/2008/10/23/model-binding-to-a-list.aspx
You should set indicies for your html elements "name" attributes like planCompareViewModel[0].PlanId, planCompareViewModel[1].PlanId to make binder able to parse them into IEnumerable.
Instead of @foreach (var planVM in Model) use for loop and render names with indexes.

How do you print in a Go test using the "testing" package?

t.Log and t.Logf do print out in your test but can often be missed as it prints on the same line as your test. What I do is Log them in a way that makes them stand out, ie

t.Run("FindIntercomUserAndReturnID should find an intercom user", func(t *testing.T) {

    id, err := ic.FindIntercomUserAndReturnID("[email protected]")
    assert.Nil(t, err)
    assert.NotNil(t, id)

    t.Logf("\n\nid: %v\n\n", *id)
})

which prints it to the terminal as,

=== RUN   TestIntercom
=== RUN   TestIntercom/FindIntercomUserAndReturnID_should_find_an_intercom_user
    TestIntercom/FindIntercomUserAndReturnID_should_find_an_intercom_user: intercom_test.go:34:

        id: 5ea8caed05a4862c0d712008

--- PASS: TestIntercom (1.45s)
    --- PASS: TestIntercom/FindIntercomUserAndReturnID_should_find_an_intercom_user (1.45s)
PASS
ok      github.com/RuNpiXelruN/third-party-delete-service   1.470s

Adding to an ArrayList Java

If you're using Java 9, there's an easy way with less number of lines without needing to initialize or add method.

List<String> list = List.of("first", "second", "third");

IOError: [Errno 13] Permission denied

I have a really stupid use case for why I got this error. Originally I was printing my data > file.txt

Then I changed my mind, and decided to use open("file.txt", "w") instead. But when I called python, I left > file.txt .....

How do I add a newline to a TextView in Android?

You need to put \n in the file string.xml

<string name="strtextparkcar">press Park my Car to store location \n</string>

PHP Checking if the current date is before or after a set date

Here's a list of all possible checks for …

"Did a date pass?"

Possible ways to obtain the value

$date = strtotime( $date );

$date > date( "U" )
$date > mktime( 0, 0, 0 )
$date > strtotime( 'now' )
$date > time()
$date > abs( intval( $_SERVER['REQUEST_TIME'] ) )

Performance Test Result (PHP 5.4.7)

I did some performance test on 1.000.000 iterations and calculated the average – Ordered fastest to slowest.

+---------------------+---------------+
|        method       |     time      |
+---------------------+---------------+
|        time()       | 0.0000006732  |
|       $_SERVER      | 0.0000009131  |
|      date("U")      | 0.0000028951  |
|     mktime(0,0,0)   | 0.000003906   |
|   strtotime("now")  | 0.0000045032  |
| new DateTime("now") | 0.0000053365  |
+---------------------+---------------+

ProTip: You can easily remember what's fastest by simply looking at the length of the function. The longer, the slower the function is.

Performance Test Setup

The following loop was run for each of the above mentioned possibilities. I converted the values to non-scientific notation for easier readability.

$loops = 1000000;
$start = microtime( true );
for ( $i = 0; $i < $loops; $i++ )
    date( "U" );
printf(
    '|    date("U")     | %s  |'."\n",
    rtrim( sprintf( '%.10F', ( microtime( true ) - $start ) / $loops ), '0' )
);

Conclusion

time() still seems to be the fastest.

Using git commit -a with vim

See this thread for an explanation: VIM for Windows - What do I type to save and exit from a file?

As I wrote there: to learn Vimming, you could use one of the quick reference cards:

Also note How can I set up an editor to work with Git on Windows? if you're not comfortable in using Vim but want to use another editor for your commit messages.

If your commit message is not too long, you could also type

git commit -a -m "your message here"

Deleting multiple columns based on column names in Pandas

You can do this in one line and one go:

df.drop([col for col in df.columns if "Unnamed" in col], axis=1, inplace=True)

This involves less moving around/copying of the object than the solutions above.

How to write a stored procedure using phpmyadmin and how to use it through php?

try this

delimiter ;;

drop procedure if exists test2;;

create procedure test2()

begin

select ‘Hello World’;

end

;;

Get the name of an object's type

Say you have var obj;

If you just want the name of obj's type, like "Object", "Array", or "String", you can use this:

Object.prototype.toString.call(obj).split(' ')[1].replace(']', '');

How to copy Java Collections list

The following output illustrates results of using copy constructor and Collections.copy():

Copy [1, 2, 3] to [1, 2, 3] using copy constructor.

Copy [1, 2, 3] to (smaller) [4, 5]
java.lang.IndexOutOfBoundsException: Source does not fit in dest
        at java.util.Collections.copy(Collections.java:556)
        at com.farenda.java.CollectionsCopy.copySourceToSmallerDest(CollectionsCopy.java:36)
        at com.farenda.java.CollectionsCopy.main(CollectionsCopy.java:14)

Copy [1, 2] to (same size) [3, 4]
source: [1, 2]
destination: [1, 2]

Copy [1, 2] to (bigger) [3, 4, 5]
source: [1, 2]
destination: [1, 2, 5]

Copy [1, 2] to (unmodifiable) [4, 5]
java.lang.UnsupportedOperationException
        at java.util.Collections$UnmodifiableList.set(Collections.java:1311)
        at java.util.Collections.copy(Collections.java:561)
        at com.farenda.java.CollectionsCopy.copyToUnmodifiableDest(CollectionsCopy.java:68)
        at com.farenda.java.CollectionsCopy.main(CollectionsCopy.java:20)

The source of full program is here: Java List copy. But the output is enough to see how java.util.Collections.copy() behaves.

Functions are not valid as a React child. This may happen if you return a Component instead of from render

What would be wrong with doing;

<div className="" key={index}>
   {i.title}
</div>

[/*Use IIFE */]

{(function () {
     if (child.children && child.children.length !== 0) {
     let menu = createMenu(child.children);
     console.log("nested menu", menu);
     return menu;
   }
 })()}

Setting initial values on load with Select2 with Ajax

The function which you are specifying as initSelection is called with the initial value as argument. So if value is empty, the function is not called.
When you specifiy value='[{"id":"IN","name":"India"}]' instead of data-initvalue the function gets called and the selection can get initialized.

How to convert uint8 Array to base64 Encoded String?

To base64-encode a UInt8Array with arbitrary data (not necessarily UTF-8) using native browser functionality:

const base64_arraybuffer = async (data) => {
    // Use a FileReader to generate a base64 data URI
    const base64url = await new Promise((r) => {
        const reader = new FileReader()
        reader.onload = () => r(reader.result)
        reader.readAsDataURL(new Blob([data]))
    })

    /*
    The result looks like 
    "data:application/octet-stream;base64,<your base64 data>", 
    so we split off the beginning:
    */
    return base64url.split(",", 2)[1]
}

// example use:
await base64_arraybuffer(new UInt8Array([1,2,3,100,200]))

How do I create a ListView with rounded corners in Android?

I'm using a custom view that I layout on top of the other ones and that just draws the 4 small corners in the same color as the background. This works whatever the view contents are and does not allocate much memory.

public class RoundedCornersView extends View {
    private float mRadius;
    private int mColor = Color.WHITE;
    private Paint mPaint;
    private Path mPath;

    public RoundedCornersView(Context context) {
        super(context);
        init();
    }

    public RoundedCornersView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();

        TypedArray a = context.getTheme().obtainStyledAttributes(
                attrs,
                R.styleable.RoundedCornersView,
                0, 0);

        try {
            setRadius(a.getDimension(R.styleable.RoundedCornersView_radius, 0));
            setColor(a.getColor(R.styleable.RoundedCornersView_cornersColor, Color.WHITE));
        } finally {
            a.recycle();
        }
    }

    private void init() {
        setColor(mColor);
        setRadius(mRadius);
    }

    private void setColor(int color) {
        mColor = color;
        mPaint = new Paint();
        mPaint.setColor(mColor);
        mPaint.setStyle(Paint.Style.FILL);
        mPaint.setAntiAlias(true);

        invalidate();
    }

    private void setRadius(float radius) {
        mRadius = radius;
        RectF r = new RectF(0, 0, 2 * mRadius, 2 * mRadius);
        mPath = new Path();
        mPath.moveTo(0,0);
        mPath.lineTo(0, mRadius);
        mPath.arcTo(r, 180, 90);
        mPath.lineTo(0,0);
        invalidate();
    }

    @Override
    protected void onDraw(Canvas canvas) {

        /*Paint paint = new Paint();
        paint.setColor(Color.RED);
        canvas.drawRect(0, 0, mRadius, mRadius, paint);*/

        int w = getWidth();
        int h = getHeight();
        canvas.drawPath(mPath, mPaint);
        canvas.save();
        canvas.translate(w, 0);
        canvas.rotate(90);
        canvas.drawPath(mPath, mPaint);
        canvas.restore();
        canvas.save();
        canvas.translate(w, h);
        canvas.rotate(180);
        canvas.drawPath(mPath, mPaint);
        canvas.restore();
        canvas.translate(0, h);
        canvas.rotate(270);
        canvas.drawPath(mPath, mPaint);
    }
}

How to set the locale inside a Debian/Ubuntu Docker container?

Specify the LANG and LC_ALL environment variables using -e when running your command:

docker run -e LANG=C.UTF-8 -e LC_ALL=C.UTF-8 -it --rm <yourimage> <yourcommand>

It's not necessary to modify the Dockerfile.

gzip: stdin: not in gzip format tar: Child returned status 1 tar: Error is not recoverable: exiting now

This means the file isn't really a gzipped tar file -- or any kind of gzipped file -- in spite of being named like one.

When you download a file with wget, check for indications like Length: unspecified [text/html] which shows it is plain text (text) and that it is intended to be interpreted as html. Check the wget output below -

[root@XXXXX opt]# wget --no-cookies --no-check-certificate --header "Cookie: gpw_e24=http%3A%2F%2Fwww.oracle.com%2F; oraclelicense=accept-securebackup-cookie" "http://download.oracle.com/otn-pub/java/jdk/8u144-b01/090f390dda5b47b9b721c7dfaa008135/jdk-8u144-linux-x64.tar.gz"
--2017-10-12 12:39:40--  http://download.oracle.com/otn-pub/java/jdk/8u144-b01/090f390dda5b47b9b721c7dfaa008135/jdk-8u144-linux-x64.tar.gz
Resolving download.oracle.com (download.oracle.com)... 23.72.136.27, 23.72.136.67
Connecting to download.oracle.com (download.oracle.com)|23.72.136.27|:80... connected.
HTTP request sent, awaiting response... 302 Not Allowed
Location: http://XXXX/FAQs/URLFiltering/ProxyWarning.html [following]
--2017-10-12 12:39:40--  http://XXXX/FAQs/URLFiltering/ProxyWarning.html
Resolving XXXX (XXXXX)... XXX.XX.XX.XXX
Connecting to XXXX (XXXX)|XXX.XX.XX.XXX|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 17121 (17K) [text/html]
Saving to: ‘jdk-8u144-linux-x64.tar.gz’

100%[=========================================================================================================================================================================>] 17,121      --.-K/s   in 0.05s   

2017-10-12 12:39:40 (349 KB/s) - ‘jdk-8u144-linux-x64.tar.gz’ saved [17121/17121]

This sort of confirms that you haven't received a gzip file.

For a correct file, the wget output will show something like Length: 185515842 (177M) [application/x-gzip] as shown in the below output -

[root@txcdtl01ss270n opt]# wget --no-cookies --no-check-certificate --header "Cookie: gpw_e24=http%3A%2F%2Fwww.oracle.com%2F; oraclelicense=accept-securebackup-cookie" "http://download.oracle.com/otn-pub/java/jdk/8u144-b01/090f390dda5b47b9b721c7dfaa008135/jdk-8u144-linux-x64.tar.gz"
--2017-10-12 12:50:06--  http://download.oracle.com/otn-pub/java/jdk/8u144-b01/090f390dda5b47b9b721c7dfaa008135/jdk-8u144-linux-x64.tar.gz
Resolving download.oracle.com (download.oracle.com)... XX.XXX.XX.XX, XX.XX.XXX.XX
Connecting to download.oracle.com (download.oracle.com)|XX.XX.XXX.XX|:80... connected.
HTTP request sent, awaiting response... 302 Moved Temporarily
Location: https://edelivery.oracle.com/otn-pub/java/jdk/8u144-b01/090f390dda5b47b9b721c7dfaa008135/jdk-8u144-linux-x64.tar.gz [following]
--2017-10-12 12:50:06--  https://edelivery.oracle.com/otn-pub/java/jdk/8u144-b01/090f390dda5b47b9b721c7dfaa008135/jdk-8u144-linux-x64.tar.gz
Resolving edelivery.oracle.com (edelivery.oracle.com)... XXX.XX.XXX.XX, 2600:1404:16:188::2d3e, 2600:1404:16:180::2d3e
Connecting to edelivery.oracle.com (edelivery.oracle.com)|XXX.XX.XX.XXX|:443... connected.
HTTP request sent, awaiting response... 302 Moved Temporarily
Location: http://download.oracle.com/otn-pub/java/jdk/8u144-b01/090f390dda5b47b9b721c7dfaa008135/jdk-8u144-linux-x64.tar.gz?AuthParam=1507827127_f44251ebbb44c6e61e7f202677f94afd [following]
--2017-10-12 12:50:07--  http://download.oracle.com/otn-pub/java/jdk/8u144-b01/090f390dda5b47b9b721c7dfaa008135/jdk-8u144-linux-x64.tar.gz?AuthParam=1507827127_f44251ebbb44c6e61
Connecting to download.oracle.com (download.oracle.com)|XX.XX.XXX.XX|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 185515842 (177M) [application/x-gzip]
Saving to: ‘jdk-8u144-linux-x64.tar.gz’

100%[=========================================================================================================================================================================>] 185,515,842 6.60MB/s   in 28s    

2017-10-12 12:50:34 (6.43 MB/s) - ‘jdk-8u144-linux-x64.tar.gz’ saved [185515842/185515842]

The above shows a correct gzip application file has been downloaded.

You can also file, head, less, view utilities to check the file. For example a HTML file would give below output -

[root@XXXXXX opt]# head jdk-8u144-linux-x64.tar.gz
<!doctype html>
<html lang="en">

<head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link href="/css/print.css" rel="stylesheet" media="print">
    <link href="/css/main.css" rel="stylesheet" media="screen">
    <link href="/css/font-awesome.min.css" rel="stylesheet">

The above shows it is indeed an HTML page which we are trying to unzip/untar - something that won't work. If it was indeed a correct zip file (binary in nature) the output of head would have produced garbage - something like below -

[root@XXXX opt]# head jdk-8u144-linux-x64.tar.gz 
x?rY?[ms?F???????t?l???DR??????j
                                       $?$,`0?h?_????/??=?@Q?w+???*?Hbfz?{?~?{?i?x??k?????}????z???w????g?????{???;{s????w?????7?N????i?
?????}
?¿g????????????7??s??????î??????~i??j?/??????#???=??=>???{}??|?????????????3???X???]9??????u?????%g?<^)?H?8?F?R?t?o?L?u??S%?ds5?2_EZn?t^??
                                                                                                                                                 ?N3??(??<??|'?q???R?N?gq?Uv!???p???rL??M??u??.?Q?5?T??BNw?!$??<>?7G'$?,Mt4WY?Gi"?=??p?)?VIN3????\ek??0??G
                                            ?<L?c?e?t-???2???G:?ia??I?<?g3???d?H????[2`?<I?A?6?W??<??C???????h??A0QL?2?4?-*
?x?????t%t1??f?>+A??,Lr?
                        ?Fe:MBH????
C?Q?r?S??<M?b?<,5???@???s???c??sp?f?=g?????k???4?}??kh)?¹Z??#d?*{???-?.N?)?e??s:?H(VQ??3*?$2??r?v?"o?_??!A???????B?l=A?|??@??0??1??5??4g?
?
???Se????H[2?????t??5?Df????$1???b$? h?Op????!Lvb!p??b?8^?Y???n?
                                                                          O??????|??lW?lu??*?N?M???
?/?^0~?~?#??q????????K??;?d???aw4?????'?~?7??ky?o?????????t?'k??f????!vo???'o???     ?.?Pn\?
               ?+??K"FA{????n2????v??!/Ok??r4?c5?x$'?.?&w?!?%??o??????2???i
                                                                               ?a0??Ag?d????GH)G7~?g???b??%?b??rt?m~?   ?????t0??   <????????????5?q?t??K(??+Z<??=???:1?\?x?p=t?`??G@F??    i?????p8?????H.???dMLE??e[?`?'n??*h[??;?0w'??6A??M?x?fpeB>&???MO???????`?@á/?"?????(??^???n??=????5??@?Mx??d:\YAn???]|?w>??S??FA9?J?k!?@?

Try downloading from the official site and check if their download links have changed. Also check your proxy settings and make sure you have the right proxies enabled to download/wget it from the correct source.

Hope this helps.

How can I find non-ASCII characters in MySQL?

for this question we can also use this method :

Question from sql zoo:
Find all details of the prize won by PETER GRÜNBERG

Non-ASCII characters

ans: select*from nobel where winner like'P% GR%_%berg';

Conda environments not showing up in Jupyter Notebook

I ran into this same problem where my new conda environment, myenv, couldn't be selected as a kernel or a new notebook. And running jupter notebook from within the env gave the same result.

My solution, and what I learned about how Jupyter notebooks recognizes conda-envs and kernels:

Installing jupyter and ipython to myenv with conda:

conda install -n myenv ipython jupyter

After that, running jupter notebook outside any env listed myenv as a kernel along with my previous environments.

Python [conda env:old]
Python [conda env:myenv]

Running the notebook once I activated the environment:

source activate myenv
jupyter notebook

hides all my other environment-kernels and only shows my language kernels:

python 2
python 3
R

Configure nginx with multiple locations with different root folders on subdomain

You need to use the alias directive for location /static:

server {

  index index.html;
  server_name test.example.com;

  root /web/test.example.com/www;

  location /static/ {
    alias /web/test.example.com/static/;
  }

}

The nginx wiki explains the difference between root and alias better than I can:

Note that it may look similar to the root directive at first sight, but the document root doesn't change, just the file system path used for the request. The location part of the request is dropped in the request Nginx issues.

Note that root and alias handle trailing slashes differently.

Powershell: Get FQDN Hostname

Local Computer FQDN via dotNet class

[System.Net.Dns]::GetHostEntry([string]$env:computername).HostName

or

[System.Net.Dns]::GetHostEntry([string]"localhost").HostName

Reference:

Dns Methods (System.Net)

note: GetHostByName method is obsolete


Local computer FQDN via WMI query

$myFQDN=(Get-WmiObject win32_computersystem).DNSHostName+"."+(Get-WmiObject win32_computersystem).Domain
Write-Host $myFQDN

Reference:

Win32_ComputerSystem class

Checkout Jenkins Pipeline Git SCM with credentials?

Adding you a quick example using git plugin GitSCM:

    checkout([
        $class: 'GitSCM', 
        branches: [[name: '*/master']], 
        doGenerateSubmoduleConfigurations: false, 
        extensions: [[$class: 'CleanCheckout']], 
        submoduleCfg: [], 
        userRemoteConfigs: [[credentialsId: '<gitCredentials>', url: '<gitRepoURL>']]
    ])

in your pipeline

stage('checkout'){
    steps{
        script{
            checkout
        }
    }
}

Configuring IntelliJ IDEA for unit testing with JUnit

If you already have test classes you may:

1) Put a cursor on a class declaration and press Alt + Enter. In the dialogue choose JUnit and press Fix. This is a standard way to create test classes in IntelliJ.

2) Alternatively you may add JUnit jars manually (download from site or take from IntelliJ files).

Linking dll in Visual Studio

You don't add or link directly against a DLL, you link against the LIB produced by the DLL.

A LIB provides symbols and other necessary data to either include a library in your code (static linking) or refer to the DLL (dynamic linking).

To link against a LIB, you need to add it to the project Properties -> Linker -> Input -> Additional Dependencies list. All LIB files here will be used in linking. You can also use a pragma like so:

#pragma comment(lib, "dll.lib")

With static linking, the code is included in your executable and there are no runtime dependencies. Dynamic linking requires a DLL with matching name and symbols be available within the search path (which is not just the path or system directory).

Importing two classes with same name. How to handle?

Yes, when you import classes with the same simple names, you must refer to them by their fully qualified class names. I would leave the import statements in, as it gives other developers a sense of what is in the file when they are working with it.

java.util.Data date1 = new java.util.Date();
my.own.Date date2 = new my.own.Date();

7-Zip command to create and extract a password-protected ZIP file on Windows?

From http://www.dotnetperls.com:

7z a secure.7z * -pSECRET

Where:

7z        : name and path of 7-Zip executable
a         : add to archive
secure.7z : name of destination archive
*         : add all files from current directory to destination archive
-pSECRET  : specify the password "SECRET"

To open :

7z x secure.7z

Then provide the SECRET password

Note: If the password contains spaces or special characters, then enclose it with single quotes

7z a secure.7z * -p"pa$$word @|"

create a trusted self-signed SSL cert for localhost (for use with Express/Node)

Go to: chrome://flags/

Enable: Allow invalid certificates for resources loaded from localhost.

You don't have the green security, but you are always allowed for https://localhost in chrome.

How to copy a string of std::string type in C++?

strcpy example:

#include <stdio.h>
#include <string.h>

int main ()
{
  char str1[]="Sample string" ;
  char str2[40] ;
  strcpy (str2,str1) ;
  printf ("str1: %s\n",str1) ;
  return 0 ;
}

Output: str1: Sample string

Your case:

A simple = operator should do the job.

string str1="Sample string" ;
string str2 = str1 ;

How to use GROUP BY to concatenate strings in SQL Server?

Don't need a cursor... a while loop is sufficient.

------------------------------
-- Setup
------------------------------

DECLARE @Source TABLE
(
  id int,
  Name varchar(30),
  Value int
)

DECLARE @Target TABLE
(
  id int,
  Result varchar(max) 
)


INSERT INTO @Source(id, Name, Value) SELECT 1, 'A', 4
INSERT INTO @Source(id, Name, Value) SELECT 1, 'B', 8
INSERT INTO @Source(id, Name, Value) SELECT 2, 'C', 9


------------------------------
-- Technique
------------------------------

INSERT INTO @Target (id)
SELECT id
FROM @Source
GROUP BY id

DECLARE @id int, @Result varchar(max)
SET @id = (SELECT MIN(id) FROM @Target)

WHILE @id is not null
BEGIN
  SET @Result = null

  SELECT @Result =
    CASE
      WHEN @Result is null
      THEN ''
      ELSE @Result + ', '
    END + s.Name + ':' + convert(varchar(30),s.Value)
  FROM @Source s
  WHERE id = @id

  UPDATE @Target
  SET Result = @Result
  WHERE id = @id

  SET @id = (SELECT MIN(id) FROM @Target WHERE @id < id)
END

SELECT *
FROM @Target

How to find all the subclasses of a class given its name?

Here's a version without recursion:

def get_subclasses_gen(cls):

    def _subclasses(classes, seen):
        while True:
            subclasses = sum((x.__subclasses__() for x in classes), [])
            yield from classes
            yield from seen
            found = []
            if not subclasses:
                return

            classes = subclasses
            seen = found

    return _subclasses([cls], [])

This differs from other implementations in that it returns the original class. This is because it makes the code simpler and:

class Ham(object):
    pass

assert(issubclass(Ham, Ham)) # True

If get_subclasses_gen looks a bit weird that's because it was created by converting a tail-recursive implementation into a looping generator:

def get_subclasses(cls):

    def _subclasses(classes, seen):
        subclasses = sum(*(frozenset(x.__subclasses__()) for x in classes))
        found = classes + seen
        if not subclasses:
            return found

        return _subclasses(subclasses, found)

    return _subclasses([cls], [])

List submodules in a Git repository

I noticed that the command provided in an answer to this question gave me the information I was looking for:

No submodule mapping found in .gitmodule for a path that's not a submodule

git ls-files --stage | grep 160000

Scroll to a specific Element Using html

If you use Jquery you can add this to your javascript:

$('.smooth-goto').on('click', function() {  
    $('html, body').animate({scrollTop: $(this.hash).offset().top - 50}, 1000);
    return false;
});

Also, don't forget to add this class to your a tag too like this:

<a href="#id-of-element" class="smooth-goto">Text</a>

Execute a command in command prompt using excel VBA

The S parameter does not do anything on its own.

/S      Modifies the treatment of string after /C or /K (see below) 
/C      Carries out the command specified by string and then terminates  
/K      Carries out the command specified by string but remains  

Try something like this instead

Call Shell("cmd.exe /S /K" & "perl a.pl c:\temp", vbNormalFocus)

You may not even need to add "cmd.exe" to this command unless you want a command window to open up when this is run. Shell should execute the command on its own.

Shell("perl a.pl c:\temp")



-Edit-
To wait for the command to finish you will have to do something like @Nate Hekman shows in his answer here

Dim wsh As Object
Set wsh = VBA.CreateObject("WScript.Shell")
Dim waitOnReturn As Boolean: waitOnReturn = True
Dim windowStyle As Integer: windowStyle = 1

wsh.Run "cmd.exe /S /C perl a.pl c:\temp", windowStyle, waitOnReturn

How do I check if PHP is connected to a database already?

// Earlier in your code
mysql_connect();
set_a_flag_that_db_is_connected();

// Later....
if (flag_is_set())
 mysql_connect(....);

How to add and remove item from array in components in Vue 2

You can use Array.push() for appending elements to an array.

For deleting, it is best to use this.$delete(array, index) for reactive objects.

Vue.delete( target, key ): Delete a property on an object. If the object is reactive, ensure the deletion triggers view updates. This is primarily used to get around the limitation that Vue cannot detect property deletions, but you should rarely need to use it.

https://vuejs.org/v2/api/#Vue-delete

CSS selector for disabled input type="submit"

As said by jensgram, IE6 does not support attribute selector. You could add a class="disabled" to select the disabled inputs so that this can work in IE6.

Directory.GetFiles: how to get only filename, not full path?

Use this to obtain only the filename.

Path.GetFileName(files[0]);

How to call window.alert("message"); from C#?

Do you mean, a message box?

MessageBox.Show("Error Message", "Error Title", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);

More information here: http://msdn.microsoft.com/en-us/library/system.windows.forms.messagebox(v=VS.100).aspx

How do I set a conditional breakpoint in gdb, when char* x points to a string whose value equals "hello"?

Since GDB 7.5 you can use these native Convenience Functions:

$_memeq(buf1, buf2, length)
$_regex(str, regex)
$_streq(str1, str2)
$_strlen(str)

Seems quite less problematic than having to execute a "foreign" strcmp() on the process' stack each time the breakpoint is hit. This is especially true for debugging multithreaded processes.

Note your GDB needs to be compiled with Python support, which is not an issue with current linux distros. To be sure, you can check it by running show configuration inside GDB and searching for --with-python. This little oneliner does the trick, too:

$ gdb -n -quiet -batch -ex 'show configuration' | grep 'with-python'
             --with-python=/usr (relocatable)

For your demo case, the usage would be

break <where> if $_streq(x, "hello")

or, if your breakpoint already exists and you just want to add the condition to it

condition <breakpoint number> $_streq(x, "hello")

$_streq only matches the whole string, so if you want something more cunning you should use $_regex, which supports the Python regular expression syntax.

how to parse json using groovy

Have you tried using JsonSlurper?

Example usage:

def slurper = new JsonSlurper()
def result = slurper.parseText('{"person":{"name":"Guillaume","age":33,"pets":["dog","cat"]}}')

assert result.person.name == "Guillaume"
assert result.person.age == 33
assert result.person.pets.size() == 2
assert result.person.pets[0] == "dog"
assert result.person.pets[1] == "cat"

"dd/mm/yyyy" date format in excel through vba

Your issue is with attempting to change your month by adding 1. 1 in date serials in Excel is equal to 1 day. Try changing your month by using the following:

NewDate = Format(DateAdd("m",1,StartDate),"dd/mm/yyyy")

MySQL & Java - Get id of the last inserted value (JDBC)

Alternatively you can do:

Statement stmt = db.prepareStatement(query, Statement.RETURN_GENERATED_KEYS);
numero = stmt.executeUpdate();

ResultSet rs = stmt.getGeneratedKeys();
if (rs.next()){
    risultato=rs.getString(1);
}

But use Sean Bright's answer instead for your scenario.

Build Maven Project Without Running Unit Tests

Run following command:

mvn clean install -DskipTests=true

What is the best Java library to use for HTTP POST, GET etc.?

I agree httpclient is something of a standard - but I guess you are looking for options so...

Restlet provides a http client specially designed for interactong with Restful web services.

Example code:

    Client client = new Client(Protocol.HTTP);
    Request r = new Request();
    r.setResourceRef("http://127.0.0.1:8182/sample");
    r.setMethod(Method.GET);
    r.getClientInfo().getAcceptedMediaTypes().add(new Preference<MediaType>(MediaType.TEXT_XML));
    client.handle(r).getEntity().write(System.out);

See http://www.restlet.org/ for more details

Using sed and grep/egrep to search and replace

Use this command:

egrep -lRZ "\.jpg|\.png|\.gif" . \
    | xargs -0 -l sed -i -e 's/\.jpg\|\.gif\|\.png/.bmp/g'
  • egrep: find matching lines using extended regular expressions

    • -l: only list matching filenames

    • -R: search recursively through all given directories

    • -Z: use \0 as record separator

    • "\.jpg|\.png|\.gif": match one of the strings ".jpg", ".gif" or ".png"

    • .: start the search in the current directory

  • xargs: execute a command with the stdin as argument

    • -0: use \0 as record separator. This is important to match the -Z of egrep and to avoid being fooled by spaces and newlines in input filenames.

    • -l: use one line per command as parameter

  • sed: the stream editor

    • -i: replace the input file with the output without making a backup

    • -e: use the following argument as expression

    • 's/\.jpg\|\.gif\|\.png/.bmp/g': replace all occurrences of the strings ".jpg", ".gif" or ".png" with ".bmp"

Find maximum value of a column and return the corresponding row values using Pandas

Use the index attribute of DataFrame. Note that I don't type all the rows in the example.

In [14]: df = data.groupby(['Country','Place'])['Value'].max()

In [15]: df.index
Out[15]: 
MultiIndex
[Spain  Manchester, UK     London    , US     Mchigan   ,        NewYork   ]

In [16]: df.index[0]
Out[16]: ('Spain', 'Manchester')

In [17]: df.index[1]
Out[17]: ('UK', 'London')

You can also get the value by that index:

In [21]: for index in df.index:
    print index, df[index]
   ....:      
('Spain', 'Manchester') 512
('UK', 'London') 778
('US', 'Mchigan') 854
('US', 'NewYork') 562

Edit

Sorry for misunderstanding what you want, try followings:

In [52]: s=data.max()

In [53]: print '%s, %s, %s' % (s['Country'], s['Place'], s['Value'])
US, NewYork, 854

Concatenating variables in Bash

Try doing this, there's no special character to concatenate in bash :

mystring="${arg1}12${arg2}endoffile"

explanations

If you don't put brackets, you will ask to concatenate $arg112 + $argendoffile (I guess that's not what you asked) like in the following example :

mystring="$arg112$arg2endoffile"

The brackets are delimiters for the variables when needed. When not needed, you can use it or not.

another solution

(less portable : require bash > 3.1)

$ arg1=foo
$ arg2=bar
$ mystring="$arg1"
$ mystring+="12"
$ mystring+="$arg2"
$ mystring+="endoffile"
$ echo "$mystring"
foo12barendoffile

See http://mywiki.wooledge.org/BashFAQ/013

Spring boot - configure EntityManager

With Spring Boot its not necessary to have any config file like persistence.xml. You can configure with annotations Just configure your DB config for JPA in the

application.properties

spring.datasource.driverClassName=oracle.jdbc.driver.OracleDriver
spring.datasource.url=jdbc:oracle:thin:@DB...
spring.datasource.username=username
spring.datasource.password=pass

spring.jpa.database-platform=org.hibernate.dialect....
spring.jpa.show-sql=true

Then you can use CrudRepository provided by Spring where you have standard CRUD transaction methods. There you can also implement your own SQL's like JPQL.

@Transactional
public interface ObjectRepository extends CrudRepository<Object, Long> {
...
}

And if you still need to use the Entity Manager you can create another class.

public class ObjectRepositoryImpl implements ObjectCustomMethods{

    @PersistenceContext
    private EntityManager em;

}

This should be in your pom.xml

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.2.5.RELEASE</version>
</parent>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-jpa</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-orm</artifactId>
    </dependency>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-core</artifactId>
        <version>4.3.11.Final</version>
    </dependency>
</dependencies>

printf with std::string?

Printf is actually pretty good to use if size matters. Meaning if you are running a program where memory is an issue, then printf is actually a very good and under rater solution. Cout essentially shifts bits over to make room for the string, while printf just takes in some sort of parameters and prints it to the screen. If you were to compile a simple hello world program, printf would be able to compile it in less than 60, 000 bits as opposed to cout, it would take over 1 million bits to compile.

For your situation, id suggest using cout simply because it is much more convenient to use. Although, I would argue that printf is something good to know.

How do you unit test private methods?

CC -Dprivate=public

"CC" is the command line compiler on the system I use. -Dfoo=bar does the equivalent of #define foo bar. So, this compilation option effectively changes all private stuff to public.

Spring Boot - How to get the running port

You can get the server port from the

HttpServletRequest
@Autowired
private HttpServletRequest request;

@GetMapping(value = "/port")
public Object getServerPort() {
   System.out.println("I am from " + request.getServerPort());
   return "I am from  " + request.getServerPort();
}
    

Failed to decode downloaded font, OTS parsing error: invalid version tag + rails 4

After trying lots of other approaches, and lots of re-installs and checks, I have just fixed the issue by clearing out browsing data from Chrome (cached images and files) and then refreshing the page.

How do I connect to a terminal to a serial-to-USB device on Ubuntu 10.10 (Maverick Meerkat)?

First check with dmesg | grep tty if system recognize your adapter. Then try to run minicom with sudo minicom -s, go to "Serial port setup" and change the first line to /dev/ttyUSB0.

Don't forget to save config as default with "Save setup as dfl". It works for me on Ubuntu 11.04 on VirtualBox.

Bash mkdir and subfolders

You can:

mkdir -p folder/subfolder

The -p flag causes any parent directories to be created if necessary.

SFTP in Python? (platform independent)

With RSA Key then refer here

Snippet:

import pysftp
import paramiko
from base64 import decodebytes

keydata = b"""AAAAB3NzaC1yc2EAAAADAQABAAABAQDl""" 
key = paramiko.RSAKey(data=decodebytes(keydata)) 
cnopts = pysftp.CnOpts()
cnopts.hostkeys.add(host, 'ssh-rsa', key)


with pysftp.Connection(host=host, username=username, password=password, cnopts=cnopts) as sftp:   
  with sftp.cd(directory):
    sftp.put(file_to_sent_to_ftp)

Get single listView SelectedItem

This works for single as well as multi selection list:

foreach (ListViewItem item in listView1.SelectedItems)
{
    int index = ListViewItem.Index;
    //index is now zero based index of selected item
}

Anybody knows any knowledge base open source?

I heard of RTM (The RT FAQ Manager). Never used it, however.

No Exception while type casting with a null in java

You can cast null to any reference type without getting any exception.

The println method does not throw null pointer because it first checks whether the object is null or not. If null then it simply prints the string "null". Otherwise it will call the toString method of that object.

Adding more details: Internally print methods call String.valueOf(object) method on the input object. And in valueOf method, this check helps to avoid null pointer exception:

return (obj == null) ? "null" : obj.toString();

For rest of your confusion, calling any method on a null object should throw a null pointer exception, if not a special case.

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

Something like this page ?

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="fr">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>BSO Communication</title>

<style type="text/css">
.submit {
    border : 0;
    background : url(ok.gif) left top no-repeat;
    height : 24px;
    width : 24px;
    cursor : pointer;
    text-indent : -9999px;
}
html:first-child .submit {
    padding-left : 1000px;
}
</style>
<!--[if IE]>
<style type="text/css">
.submit {
    text-indent : 0;
    color : expression(this.value = '');
}
</style>
<![endif]-->
</head>

<body>
    <h1>Display input submit as image with CSS</h1>

    <p>Take a look at <a href="/2007/07/26/afficher-un-input-submit-comme-une-image/">the related article</a> (in french).</p>
    <form action="" method="get">
        <fieldset>
            <legend>Some form</legend>
            <p class="field">
                <label for="input">Some value</label>

                <input type="text" id="input" name="value" />
                <input type="submit" class="submit" />
            </p>
        </fieldset>
    </form>

    <hr />
    <p>This page is part of the <a href="http://www.bsohq.fr">BSO Communication blog</a>.</p>

</body>
</html>

Add regression line equation and R^2 on graph

really love @Ramnath solution. To allow use to customize the regression formula (instead of fixed as y and x as literal variable names), and added the p-value into the printout as well (as @Jerry T commented), here is the mod:

lm_eqn <- function(df, y, x){
    formula = as.formula(sprintf('%s ~ %s', y, x))
    m <- lm(formula, data=df);
    # formating the values into a summary string to print out
    # ~ give some space, but equal size and comma need to be quoted
    eq <- substitute(italic(target) == a + b %.% italic(input)*","~~italic(r)^2~"="~r2*","~~p~"="~italic(pvalue), 
         list(target = y,
              input = x,
              a = format(as.vector(coef(m)[1]), digits = 2), 
              b = format(as.vector(coef(m)[2]), digits = 2), 
             r2 = format(summary(m)$r.squared, digits = 3),
             # getting the pvalue is painful
             pvalue = format(summary(m)$coefficients[2,'Pr(>|t|)'], digits=1)
            )
          )
    as.character(as.expression(eq));                 
}

geom_point() +
  ggrepel::geom_text_repel(label=rownames(mtcars)) +
  geom_text(x=3,y=300,label=lm_eqn(mtcars, 'hp','wt'),color='red',parse=T) +
  geom_smooth(method='lm')

enter image description here Unfortunately, this doesn't work with facet_wrap or facet_grid.

"Input string was not in a correct format."

Please change your code like below.

  int QuestionID;

  bool IsIntValue = Int32.TryParse("YOUR-VARIABLE", out QuestionID);

  if (IsIntValue)
  {
      // YOUR CODE HERE  
  }

Hope i will be help.

Iterate a list with indexes in Python

Here's another using the zip function.

>>> a = [3, 7, 19]
>>> zip(range(len(a)), a)
[(0, 3), (1, 7), (2, 19)]

How to get Exception Error Code in C#

You can use this to check the exception and the inner exception for a Win32Exception derived exception.

catch (Exception e) {  
    var w32ex = e as Win32Exception;
    if(w32ex == null) {
        w32ex = e.InnerException as Win32Exception;
    }    
    if(w32ex != null) {
        int code =  w32ex.ErrorCode;
        // do stuff
    }    
    // do other stuff   
}

Starting with C# 6, when can be used in a catch statement to specify a condition that must be true for the handler for a specific exception to execute.

catch (Win32Exception ex) when (ex.InnerException is Win32Exception) {
    var w32ex = (Win32Exception)ex.InnerException;
    var code =  w32ex.ErrorCode;
}

As in the comments, you really need to see what exception is actually being thrown to understand what you can do, and in which case a specific catch is preferred over just catching Exception. Something like:

  catch (BlahBlahException ex) {  
      // do stuff   
  }

Also System.Exception has a HRESULT

 catch (Exception ex) {  
     var code = ex.HResult;
 }

However, it's only available from .NET 4.5 upwards.

How to get the hours difference between two date objects?

Try using getTime (mdn doc) :

var diff = Math.abs(date1.getTime() - date2.getTime()) / 3600000;
if (diff < 18) { /* do something */ }

Using Math.abs() we don't know which date is the smallest. This code is probably more relevant :

var diff = (date1 - date2) / 3600000;
if (diff < 18) { array.push(date1); }

Aligning textviews on the left and right edges in Android layout

<TextView
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:text="Hello world" />

<View
    android:layout_width="0dp"
    android:layout_height="match_parent"
    android:layout_weight="1" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Gud bye" />

How to read from a text file using VBScript?

Use first the method OpenTextFile, and then...

either read the file at once with the method ReadAll:

Set file = fso.OpenTextFile("C:\test.txt", 1)
content = file.ReadAll

or line by line with the method ReadLine:

Set dict = CreateObject("Scripting.Dictionary")
Set file = fso.OpenTextFile ("c:\test.txt", 1)
row = 0
Do Until file.AtEndOfStream
  line = file.Readline
  dict.Add row, line
  row = row + 1
Loop

file.Close

'Loop over it
For Each line in dict.Items
  WScript.Echo line
Next

Changing MongoDB data store directory

Copy the contents of /var/lib/mongodb to /data/db. The files you should be looking for should have names like your_db_name.ns and your_dbname.n where n is a number starting with 0. If you do not see such files under /var/lib/mongodb, search for them on your filesystem.

Once copied over, use --dbpath=/data/db when starting MongoDB via the mongod command.

Calling a Fragment method from a parent Activity

Too late for the question but will post my answer anyway for anyone still needs it. I found an easier way to implement this, without using fragment id or fragment tag, since that's what I was seeking for.

First, I declared my Fragment in my ParentActivity class:

MyFragment myFragment;

Initialized my viewPager as usual, with the fragment I already added in the class above. Then, created a public method called scrollToTop in myFragment that does what I want to do from ParentActivity, let's say scroll my recyclerview to the top.

public void scrollToTop(){
    mMainRecyclerView.smoothScrollToPosition(0);
}

Now, in ParentActivity I called the method as below:

try{
   myFragment.scrollToTop();
}catch (Exception e){
   e.printStackTrace();
}

Android. Fragment getActivity() sometimes returns null

I've been battling this kind of problem for a while, and I think I've come up with a reliable solution.

It's pretty difficult to know for sure that this.getActivity() isn't going to return null for a Fragment, especially if you're dealing with any kind of network behaviour which gives your code ample time to withdraw Activity references.

In the solution below, I declare a small management class called the ActivityBuffer. Essentially, this class deals with maintaining a reliable reference to an owning Activity, and promising to execute Runnables within a valid Activity context whenever there's a valid reference available. The Runnables are scheduled for execution on the UI Thread immediately if the Context is available, otherwise execution is deferred until that Context is ready.

/** A class which maintains a list of transactions to occur when Context becomes available. */
public final class ActivityBuffer {

    /** A class which defines operations to execute once there's an available Context. */
    public interface IRunnable {
        /** Executes when there's an available Context. Ideally, will it operate immediately. */
        void run(final Activity pActivity);
    }

    /* Member Variables. */
    private       Activity        mActivity;
    private final List<IRunnable> mRunnables;

    /** Constructor. */
    public ActivityBuffer() {
        // Initialize Member Variables.
        this.mActivity  = null;
        this.mRunnables = new ArrayList<IRunnable>();
    }

    /** Executes the Runnable if there's an available Context. Otherwise, defers execution until it becomes available. */
    public final void safely(final IRunnable pRunnable) {
        // Synchronize along the current instance.
        synchronized(this) {
            // Do we have a context available?
            if(this.isContextAvailable()) {
                // Fetch the Activity.
                final Activity lActivity = this.getActivity();
                // Execute the Runnable along the Activity.
                lActivity.runOnUiThread(new Runnable() { @Override public final void run() { pRunnable.run(lActivity); } });
            }
            else {
                // Buffer the Runnable so that it's ready to receive a valid reference.
                this.getRunnables().add(pRunnable);
            }
        }
    }

    /** Called to inform the ActivityBuffer that there's an available Activity reference. */
    public final void onContextGained(final Activity pActivity) {
        // Synchronize along ourself.
        synchronized(this) {
            // Update the Activity reference.
            this.setActivity(pActivity);
            // Are there any Runnables awaiting execution?
            if(!this.getRunnables().isEmpty()) {
                // Iterate the Runnables.
                for(final IRunnable lRunnable : this.getRunnables()) {
                    // Execute the Runnable on the UI Thread.
                    pActivity.runOnUiThread(new Runnable() { @Override public final void run() {
                        // Execute the Runnable.
                        lRunnable.run(pActivity);
                    } });
                }
                // Empty the Runnables.
                this.getRunnables().clear();
            }
        }
    }

    /** Called to inform the ActivityBuffer that the Context has been lost. */
    public final void onContextLost() {
        // Synchronize along ourself.
        synchronized(this) {
            // Remove the Context reference.
            this.setActivity(null);
        }
    }

    /** Defines whether there's a safe Context available for the ActivityBuffer. */
    public final boolean isContextAvailable() {
        // Synchronize upon ourself.
        synchronized(this) {
            // Return the state of the Activity reference.
            return (this.getActivity() != null);
        }
    }

    /* Getters and Setters. */
    private final void setActivity(final Activity pActivity) {
        this.mActivity = pActivity;
    }

    private final Activity getActivity() {
        return this.mActivity;
    }

    private final List<IRunnable> getRunnables() {
        return this.mRunnables;
    }

}

In terms of its implementation, we must take care to apply the life cycle methods to coincide with the behaviour described above by Pawan M:

public class BaseFragment extends Fragment {

    /* Member Variables. */
    private ActivityBuffer mActivityBuffer;

    public BaseFragment() {
        // Implement the Parent.
        super();
        // Allocate the ActivityBuffer.
        this.mActivityBuffer = new ActivityBuffer();
    }

    @Override
    public final void onAttach(final Context pContext) {
        // Handle as usual.
        super.onAttach(pContext);
        // Is the Context an Activity?
        if(pContext instanceof Activity) {
            // Cast Accordingly.
            final Activity lActivity = (Activity)pContext;
            // Inform the ActivityBuffer.
            this.getActivityBuffer().onContextGained(lActivity);
        }
    }

    @Deprecated @Override
    public final void onAttach(final Activity pActivity) {
        // Handle as usual.
        super.onAttach(pActivity);
        // Inform the ActivityBuffer.
        this.getActivityBuffer().onContextGained(pActivity);
    }

    @Override
    public final void onDetach() {
        // Handle as usual.
        super.onDetach();
        // Inform the ActivityBuffer.
        this.getActivityBuffer().onContextLost();
    }

    /* Getters. */
    public final ActivityBuffer getActivityBuffer() {
        return this.mActivityBuffer;
    }

}

Finally, in any areas within your Fragment that extends BaseFragment that you're untrustworthy about a call to getActivity(), simply make a call to this.getActivityBuffer().safely(...) and declare an ActivityBuffer.IRunnable for the task!

The contents of your void run(final Activity pActivity) are then guaranteed to execute along the UI Thread.

The ActivityBuffer can then be used as follows:

this.getActivityBuffer().safely(
  new ActivityBuffer.IRunnable() {
    @Override public final void run(final Activity pActivity) {
       // Do something with guaranteed Context.
    }
  }
);

What is the difference between T(n) and O(n)?

Rather than provide a theoretical definition, which are beautifully summarized here already, I'll give a simple example:

Assume the run time of f(i) is O(1). Below is a code fragment whose asymptotic runtime is T(n). It always calls the function f(...) n times. Both the lower and the upper bound is n.

for(int i=0; i<n; i++){
    f(i);
}

The second code fragment below has the asymptotic runtime of O(n). It calls the function f(...) at most n times. The upper bound is n, but the lower bound could be O(1) or O(log(n)), depending on what happens inside f2(i).

for(int i=0; i<n; i++){
    if( f2(i) ) break;
    f(i);
}

Submit button doesn't work

Hello from the future.

For clarity, I just wanted to add (as this was pretty high up in google) - we can now use

<button type="submit">Upload Stuff</button>

And to reset a form

<button type="reset" value="Reset">Reset</button>

Check out button types

We can also attach buttons to submit forms like this:

<button type="submit" form="myform" value="Submit">Submit</button>

Insert PHP code In WordPress Page and Post

Description:

there are 3 steps to run PHP code inside post or page.

  1. In functions.php file (in your theme) add new function

  2. In functions.php file (in your theme) register new shortcode which call your function:

add_shortcode( 'SHORCODE_NAME', 'FUNCTION_NAME' );
  1. use your new shortcode

Example #1: just display text.

In functions:

function simple_function_1() {
    return "Hello World!";
}

add_shortcode( 'own_shortcode1', 'simple_function_1' );

In post/page:

[own_shortcode1]

Effect:

Hello World!

Example #2: use for loop.

In functions:

function simple_function_2() {
    $output = "";
    
    for ($number = 1; $number < 10; $number++) {    
        // Append numbers to the string
        $output .= "$number<br>";
    } 
    
    return "$output";
}

add_shortcode( 'own_shortcode2', 'simple_function_2' );

In post/page:

[own_shortcode2]

Effect:

1
2
3
4
5
6
7
8
9

Example #3: use shortcode with arguments

In functions:

function simple_function_3($name) {
    return "Hello $name";
}

add_shortcode( 'own_shortcode3', 'simple_function_3' );

In post/page:

[own_shortcode3 name="John"]

Effect:

Hello John

Example #3 - without passing arguments

In post/page:

[own_shortcode3]

Effect:

Hello 

javascript: optional first argument in function

There are 2 ways to do this.

1)

function something(options) {
    var timeToLive = options.timeToLive || 200; // default to 200 if not set
    ...
}

2)

function something(timeToDie /*, timeToLive*/) {
    var timeToLive = arguments[1] || 200; // default to 200 if not set
    ..
}

In 1), options is a JS object with what ever attributes are required. This is easier to maintain and extend.

In 2), the function signature is clear to read and understand that a second argument can be provided. I've seen this style used in Mozilla code and documentation.

Reset the database (purge all), then seed a database

on Rails 6 you can now do something like

rake db:seed:replant This Truncates tables of each database for current environment and loads the seeds

https://blog.saeloun.com/2019/09/30/rails-6-adds-db-seed-replant-task-and-db-truncate_all.html

$ rails db:seed:replant --trace
** Invoke db:seed:replant (first_time)
** Invoke db:load_config (first_time)
** Invoke environment (first_time)
** Execute environment
** Execute db:load_config
** Invoke db:truncate_all (first_time)
** Invoke db:load_config
** Invoke db:check_protected_environments (first_time)
** Invoke db:load_config
** Execute db:check_protected_environments
** Execute db:truncate_all
** Invoke db:seed (first_time)
** Invoke db:load_config
** Execute db:seed
** Invoke db:abort_if_pending_migrations (first_time)
** Invoke db:load_config
** Execute db:abort_if_pending_migrations
** Execute db:seed:replant

How to read an entire file to a string using C#?

Take a look at the File.ReadAllText() method

Some important remarks:

This method opens a file, reads each line of the file, and then adds each line as an element of a string. It then closes the file. A line is defined as a sequence of characters followed by a carriage return ('\r'), a line feed ('\n'), or a carriage return immediately followed by a line feed. The resulting string does not contain the terminating carriage return and/or line feed.

This method attempts to automatically detect the encoding of a file based on the presence of byte order marks. Encoding formats UTF-8 and UTF-32 (both big-endian and little-endian) can be detected.

Use the ReadAllText(String, Encoding) method overload when reading files that might contain imported text, because unrecognized characters may not be read correctly.

The file handle is guaranteed to be closed by this method, even if exceptions are raised

Open button in new window?

Opens a new window with the url you supplied :)

<button class="button" onClick="window.open('http://www.example.com');">
     <span class="icon">Open</span>
</button>

hope that helps :)

Save plot to image file instead of displaying it using Matplotlib

Just found this link on the MatPlotLib documentation addressing exactly this issue: http://matplotlib.org/faq/howto_faq.html#generate-images-without-having-a-window-appear

They say that the easiest way to prevent the figure from popping up is to use a non-interactive backend (eg. Agg), via matplotib.use(<backend>), eg:

import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
plt.plot([1,2,3])
plt.savefig('myfig')

I still personally prefer using plt.close( fig ), since then you have the option to hide certain figures (during a loop), but still display figures for post-loop data processing. It is probably slower than choosing a non-interactive backend though - would be interesting if someone tested that.

UPDATE: for Spyder, you usually can't set the backend in this way (Because Spyder usually loads matplotlib early, preventing you from using matplotlib.use()).

Instead, use plt.switch_backend('Agg'), or Turn off "enable support" in the Spyder prefs and run the matplotlib.use('Agg') command yourself.

From these two hints: one, two

Create a directory if it does not exist and then create the files in that directory as well

code:

// Create Directory if not exist then Copy a file.


public static void copyFile_Directory(String origin, String destDir, String destination) throws IOException {

    Path FROM = Paths.get(origin);
    Path TO = Paths.get(destination);
    File directory = new File(String.valueOf(destDir));

    if (!directory.exists()) {
        directory.mkdir();
    }
        //overwrite the destination file if it exists, and copy
        // the file attributes, including the rwx permissions
     CopyOption[] options = new CopyOption[]{
                StandardCopyOption.REPLACE_EXISTING,
                StandardCopyOption.COPY_ATTRIBUTES

        };
        Files.copy(FROM, TO, options);


}

JavaScript: Check if mouse button down?

the solution isn't good. one could "mousedown" on the document, then "mouseup" outside the browser, and on this case the browser would still be thinking the mouse is down.

the only good solution is using IE.event object.

How to read a text file from server using JavaScript?

You can use hidden frame, load the file in there and parse its contents.

HTML:

<iframe id="frmFile" src="test.txt" onload="LoadFile();" style="display: none;"></iframe>

JavaScript:

<script type="text/javascript">
function LoadFile() {
    var oFrame = document.getElementById("frmFile");
    var strRawContents = oFrame.contentWindow.document.body.childNodes[0].innerHTML;
    while (strRawContents.indexOf("\r") >= 0)
        strRawContents = strRawContents.replace("\r", "");
    var arrLines = strRawContents.split("\n");
    alert("File " + oFrame.src + " has " + arrLines.length + " lines");
    for (var i = 0; i < arrLines.length; i++) {
        var curLine = arrLines[i];
        alert("Line #" + (i + 1) + " is: '" + curLine + "'");
    }
}
</script>

Note: in order for this to work in Chrome browser, you should start it with the --allow-file-access-from-files flag. credit.

SSH Key: “Permissions 0644 for 'id_rsa.pub' are too open.” on mac

giving permision 400 makes the key private and not accessible by someone unknown. It makes the key as a protected one.

chmod 400 /Users/tudouya/.ssh/vm/vm_id_rsa.pub

Change a Nullable column to NOT NULL with Default Value

you need to execute two queries:

One - to add the default value to the column required

ALTER TABLE 'Table_Name` ADD DEFAULT 'value' FOR 'Column_Name'

i want add default value to Column IsDeleted as below:

Example: ALTER TABLE [dbo].[Employees] ADD Default 0 for IsDeleted

Two - to alter the column value nullable to not null

ALTER TABLE 'table_name' ALTER COLUMN 'column_name' 'data_type' NOT NULL

i want to make the column IsDeleted as not null

ALTER TABLE [dbo].[Employees] Alter Column IsDeleted BIT NOT NULL

Is there an equivalent to background-size: cover and contain for image elements?

What you could do is use the 'style' attribute to add the background image to the element, that way you will still be calling the image in the HTML but you will still be able to use the background-size: cover css behaviour:

HTML:

    <div class="image-div" style="background-image:url(yourimage.jpg)">
    </div>

CSS:

    .image-div{
    background-size: cover;
    }

This is how I add the background-size: cover behaviour to elements that I need to dynamically load into HTML. You can then use awesome css classes like background-position: center. boom

Open Form2 from Form1, close Form1 from Form2

if you just want to close form1 from form2 without closing form2 as well in the process, as the title suggests, then you could pass a reference to form 1 along to form 2 when you create it and use that to close form 1

for example you could add a

public class Form2 : Form
{
    Form2(Form1 parentForm):base()
    {
        this.parentForm = parentForm;
    }

    Form1 parentForm;
    .....
}

field and constructor to Form2

if you want to first close form2 and then form1 as the text of the question suggests, I'd go with Justins answer of returning an appropriate result to form1 on upon closing form2

List only stopped Docker containers

docker container list -f "status=exited"

or

docker container ls -f "status=exited"

or

 docker ps -f "status=exited"

ImportError: cannot import name NUMPY_MKL

Reinstall numpy-1.11.0_XXX.whl (for your Python) from www.lfd.uci.edu/~gohlke/pythonlibs. This file has the same name and version if compare with the variant downloaded by me earlier 29.03.2016, but its size and content differ from old variant. After re-installation error disappeared.

Second option - return back to scipy 0.17.0 from 0.17.1

P.S. I use Windows 64-bit version of Python 3.5.1, so can't guarantee that numpy for Python 2.7 is already corrected.

Formula px to dp, dp to px android

Below funtions worked well for me across devices.

It is taken from https://gist.github.com/laaptu/7867851

public static float convertPixelsToDp(float px){
    DisplayMetrics metrics = Resources.getSystem().getDisplayMetrics();
    float dp = px / (metrics.densityDpi / 160f);
    return Math.round(dp);
}

public static float convertDpToPixel(float dp){
    DisplayMetrics metrics = Resources.getSystem().getDisplayMetrics();
    float px = dp * (metrics.densityDpi / 160f);
    return Math.round(px);
}

Can I set a breakpoint on 'memory access' in GDB?

Assuming the first answer is referring to the C-like syntax (char *)(0x135700 +0xec1a04f) then the answer to do rwatch *0x135700+0xec1a04f is incorrect. The correct syntax is rwatch *(0x135700+0xec1a04f).

The lack of ()s there caused me a great deal of pain trying to use watchpoints myself.

Is there a .NET/C# wrapper for SQLite?

Version 1.2 of Monotouch includes support for System.Data. You can find more details here: http://monotouch.net/Documentation/System.Data

But basically it allows you to use the usual ADO .NET patterns with sqlite.

Extract a subset of a dataframe based on a condition involving a field

Just to extend the answer above you can also index your columns rather than specifying the column names which can also be useful depending on what you're doing. Given that your location is the first field it would look like this:

    bar <- foo[foo[ ,1] == "there", ]

This is useful because you can perform operations on your column value, like looping over specific columns (and you can do the same by indexing row numbers too).

This is also useful if you need to perform some operation on more than one column because you can then specify a range of columns:

    foo[foo[ ,c(1:N)], ]

Or specific columns, as you would expect.

    foo[foo[ ,c(1,5,9)], ]

YAML: Do I need quotes for strings in YAML?

After a brief review of the YAML cookbook cited in the question and some testing, here's my interpretation:

  • In general, you don't need quotes.
  • Use quotes to force a string, e.g. if your key or value is 10 but you want it to return a String and not a Fixnum, write '10' or "10".
  • Use quotes if your value includes special characters, (e.g. :, {, }, [, ], ,, &, *, #, ?, |, -, <, >, =, !, %, @, \).
  • Single quotes let you put almost any character in your string, and won't try to parse escape codes. '\n' would be returned as the string \n.
  • Double quotes parse escape codes. "\n" would be returned as a line feed character.
  • The exclamation mark introduces a method, e.g. !ruby/sym to return a Ruby symbol.

Seems to me that the best approach would be to not use quotes unless you have to, and then to use single quotes unless you specifically want to process escape codes.

Update

"Yes" and "No" should be enclosed in quotes (single or double) or else they will be interpreted as TrueClass and FalseClass values:

en:
  yesno:
    'yes': 'Yes'
    'no': 'No'

Git : fatal: Could not read from remote repository. Please make sure you have the correct access rights and the repository exists

Try:

git config --global credential.helper cache

This command prevents git to ask username and password, not forever but with a default limit to 15 minutes.

git config --global credential.helper 'cache --timeout=3600'

This moves the default limit to 1 hour.

How to sum the values of one column of a dataframe in spark/scala

Not sure this was around when this question was asked but:

df.describe().show("columnName")

gives mean, count, stdtev stats on a column. I think it returns on all columns if you just do .show()

How to find schema name in Oracle ? when you are connected in sql session using read only user

To create a read-only user, you have to setup a different user than the one owning the tables you want to access.

If you just create the user and grant SELECT permission to the read-only user, you'll need to prepend the schema name to each table name. To avoid this, you have basically two options:

  1. Set the current schema in your session:
ALTER SESSION SET CURRENT_SCHEMA=XYZ
  1. Create synonyms for all tables:
CREATE SYNONYM READER_USER.TABLE1 FOR XYZ.TABLE1

So if you haven't been told the name of the owner schema, you basically have three options. The last one should always work:

  1. Query the current schema setting:
SELECT SYS_CONTEXT('USERENV','CURRENT_SCHEMA') FROM DUAL
  1. List your synonyms:
SELECT * FROM ALL_SYNONYMS WHERE OWNER = USER
  1. Investigate all tables (with the exception of the some well-known standard schemas):
SELECT * FROM ALL_TABLES WHERE OWNER NOT IN ('SYS', 'SYSTEM', 'CTXSYS', 'MDSYS');

php timeout - set_time_limit(0); - don't work

Check the php.ini

ini_set('max_execution_time', 300); //300 seconds = 5 minutes

ini_set('max_execution_time', 0); //0=NOLIMIT

How to get a certain element in a list, given the position?

If you frequently need to access the Nth element of a sequence, std::list, which is implemented as a doubly linked list, is probably not the right choice. std::vector or std::deque would likely be better.

That said, you can get an iterator to the Nth element using std::advance:

std::list<Object> l;
// add elements to list 'l'...

unsigned N = /* index of the element you want to retrieve */;
if (l.size() > N)
{
    std::list<Object>::iterator it = l.begin();
    std::advance(it, N);
    // 'it' points to the element at index 'N'
}

For a container that doesn't provide random access, like std::list, std::advance calls operator++ on the iterator N times. Alternatively, if your Standard Library implementation provides it, you may call std::next:

if (l.size() > N)
{
    std::list<Object>::iterator it = std::next(l.begin(), N);
}

std::next is effectively wraps a call to std::advance, making it easier to advance an iterator N times with fewer lines of code and fewer mutable variables. std::next was added in C++11.

Regular expression [Any number]

UPDATE: for your updated question

variable.match(/\[[0-9]+\]/);

Try this:

variable.match(/[0-9]+/);    // for unsigned integers
variable.match(/[-0-9]+/);   // for signed integers
variable.match(/[-.0-9]+/);  // for signed float numbers

Hope this helps!

Correct way to pass multiple values for same parameter name in GET request

Indeed, there is no defined standard. To support that information, have a look at wikipedia, in the Query String chapter. There is the following comment:

While there is no definitive standard, most web frameworks allow multiple values to be associated with a single field.[3][4]

Furthermore, when you take a look at the RFC 3986, in section 3.4 Query, there is no definition for parameters with multiple values.

Most applications use the first option you have shown: http://server/action?id=a&id=b. To support that information, take a look at this Stackoverflow link, and this MSDN link regarding ASP.NET applications, which use the same standard for parameters with multiple values.

However, since you are developing the APIs, I suggest you to do what is the easiest for you, since the caller of the API will not have much trouble creating the query string.

Index inside map() function

Array.prototype.map() index:

One can access the index Array.prototype.map() via the second argument of the callback function. Here is an example:

_x000D_
_x000D_
const array = [1, 2, 3, 4];_x000D_
_x000D_
_x000D_
const map = array.map((x, index) => {_x000D_
  console.log(index);_x000D_
  return x + index;_x000D_
});_x000D_
_x000D_
console.log(map);
_x000D_
_x000D_
_x000D_

Other arguments of Array.prototype.map():

  • The third argument of the callback function exposes the array on which map was called upon
  • The second argument of Array.map() is a object which will be the this value for the callback function. Keep in mind that you have to use the regular function keyword in order to declare the callback since an arrow function doesn't have its own binding to the this keyword.

For example:

_x000D_
_x000D_
const array = [1, 2, 3, 4];_x000D_
_x000D_
const thisObj = {prop1: 1}_x000D_
_x000D_
_x000D_
const map = array.map( function (x, index, array) {_x000D_
  console.log(array);_x000D_
  console.log(this)_x000D_
}, thisObj);
_x000D_
_x000D_
_x000D_

How to call a parent method from child class in javascript?

In case of multiple inheritance level, this function can be used as a super() method in other languages. Here is a demo fiddle, with some tests, you can use it like this, inside your method use : call_base(this, 'method_name', arguments);

It make use of quite recent ES functions, an compatibility with older browsers is not guarantee. Tested in IE11, FF29, CH35.

/**
 * Call super method of the given object and method.
 * This function create a temporary variable called "_call_base_reference",
 * to inspect whole inheritance linage. It will be deleted at the end of inspection.
 *
 * Usage : Inside your method use call_base(this, 'method_name', arguments);
 *
 * @param {object} object The owner object of the method and inheritance linage
 * @param {string} method The name of the super method to find.
 * @param {array} args The calls arguments, basically use the "arguments" special variable.
 * @returns {*} The data returned from the super method.
 */
function call_base(object, method, args) {
    // We get base object, first time it will be passed object,
    // but in case of multiple inheritance, it will be instance of parent objects.
    var base = object.hasOwnProperty('_call_base_reference') ? object._call_base_reference : object,
    // We get matching method, from current object,
    // this is a reference to define super method.
            object_current_method = base[method],
    // Temp object wo receive method definition.
            descriptor = null,
    // We define super function after founding current position.
            is_super = false,
    // Contain output data.
            output = null;
    while (base !== undefined) {
        // Get method info
        descriptor = Object.getOwnPropertyDescriptor(base, method);
        if (descriptor !== undefined) {
            // We search for current object method to define inherited part of chain.
            if (descriptor.value === object_current_method) {
                // Further loops will be considered as inherited function.
                is_super = true;
            }
            // We already have found current object method.
            else if (is_super === true) {
                // We need to pass original object to apply() as first argument,
                // this allow to keep original instance definition along all method
                // inheritance. But we also need to save reference to "base" who
                // contain parent class, it will be used into this function startup
                // to begin at the right chain position.
                object._call_base_reference = base;
                // Apply super method.
                output = descriptor.value.apply(object, args);
                // Property have been used into super function if another
                // call_base() is launched. Reference is not useful anymore.
                delete object._call_base_reference;
                // Job is done.
                return output;
            }
        }
        // Iterate to the next parent inherited.
        base = Object.getPrototypeOf(base);
    }
}

Starting Docker as Daemon on Ubuntu

I had a same issue on ubuntu 14.04 Here is a solution

sudo service docker start

or you can list images

docker images

How can I solve ORA-00911: invalid character error?

The option(s) to resolve this Oracle error are:

Option #1 This error occurs when you try to use a special character in a SQL statement. If a special character other than $, _, and # is used in the name of a column or table, the name must be enclosed in double quotations.

Option #2 This error may occur if you've pasted your SQL into your editor from another program. Sometimes there are non-printable characters that may be present. In this case, you should try retyping your SQL statement and then re-execute it.

Option #3 This error occurs when a special character is used in a SQL WHERE clause and the value is not enclosed in single quotations.

For example, if you had the following SQL statement:

SELECT * FROM suppliers WHERE supplier_name = ?;

How to implement a secure REST API with node.js

I just finished a sample app that does this in a pretty basic, but clear way. It uses mongoose with mongodb to store users and passport for auth management.

https://github.com/Khelldar/Angular-Express-Train-Seed

What's the difference between process.cwd() vs __dirname?

$ find proj

proj
proj/src
proj/src/index.js

$ cat proj/src/index.js

console.log("process.cwd() = " + process.cwd());
console.log("__dirname = " + __dirname);

$ cd proj; node src/index.js

process.cwd() = /tmp/proj
__dirname = /tmp/proj/src

How do I fix the indentation of selected lines in Visual Studio

Selecting the text to fix, and CtrlK, CtrlF shortcut certainly works. However, I generally find that if a particular method (for instance) has it's indentation messed up, simply removing the closing brace of the method, and re-adding, in fact fixes the indentation anyway, thereby doing without the need to select the code before hand, ergo is quicker. ymmv.

Git copy changes from one branch to another

This is 2 step process

  • git checkout BranchB ( destination branch is BranchB, so we need the head on this branch)
  • git merge BranchA (it will merge BranchB with BranchA. Here you have merged code in branch B)

If you want to push your branch code to remote repo then do

  • git push origin master (it will push your BranchB code to remote repo)

Getting The ASCII Value of a character in a C# string

Here's an alternative since you don't like the cast to int:

foreach(byte b in System.Text.Encoding.UTF8.GetBytes(str.ToCharArray()))
    Console.Write(b.ToString());

How to open a website when a Button is clicked in Android application?

I just need one line to show a website in my app:

startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("http://match4app.com")));

CSS last-child(-1)

You can use :nth-last-child(); in fact, besides :nth-last-of-type() I don't know what else you could use. I'm not sure what you mean by "dynamic", but if you mean whether the style applies to the new second last child when more children are added to the list, yes it will. Interactive fiddle.

ul li:nth-last-child(2)

Get all child views inside LinearLayout at once

use this

    final int childCount = mainL.getChildCount();
    for (int i = 0; i < childCount; i++) {
          View element = mainL.getChildAt(i);

        // EditText
        if (element instanceof EditText) {
            EditText editText = (EditText)element;
            System.out.println("ELEMENTS EditText getId=>"+editText.getId()+ " getTag=>"+element.getTag()+
            " getText=>"+editText.getText());
        }

        // CheckBox
        if (element instanceof CheckBox) {
            CheckBox checkBox = (CheckBox)element;
            System.out.println("ELEMENTS CheckBox getId=>"+checkBox.getId()+ " getTag=>"+checkBox.getTag()+
            " getText=>"+checkBox.getText()+" isChecked=>"+checkBox.isChecked());
        }

        // DatePicker
        if (element instanceof DatePicker) {
            DatePicker datePicker = (DatePicker)element;
            System.out.println("ELEMENTS DatePicker getId=>"+datePicker.getId()+ " getTag=>"+datePicker.getTag()+
            " getDayOfMonth=>"+datePicker.getDayOfMonth());
        }

        // Spinner
        if (element instanceof Spinner) {
            Spinner spinner = (Spinner)element;
            System.out.println("ELEMENTS Spinner getId=>"+spinner.getId()+ " getTag=>"+spinner.getTag()+
            " getSelectedItemId=>"+spinner.getSelectedItemId()+
            " getSelectedItemPosition=>"+spinner.getSelectedItemPosition()+
            " getTag(key)=>"+spinner.getTag(spinner.getSelectedItemPosition()));
        }

    }

Adding double quote delimiters into csv file

In Excel for Mac at least, you can do this by saving as "CSV for MS DOS" which adds double quotes for any field which needs them.

How do I find the caller of a method using stacktrace or reflection?

I've done this before. You can just create a new exception and grab the stack trace on it without throwing it, then examine the stack trace. As the other answer says though, it's extremely costly--don't do it in a tight loop.

I've done it before for a logging utility on an app where performance didn't matter much (Performance rarely matters much at all, actually--as long as you display the result to an action such as a button click quickly).

It was before you could get the stack trace, exceptions just had .printStackTrace() so I had to redirect System.out to a stream of my own creation, then (new Exception()).printStackTrace(); Redirect System.out back and parse the stream. Fun stuff.

How to resolve a Java Rounding Double issue

To control the precision of floating point arithmetic, you should use java.math.BigDecimal. Read The need for BigDecimal by John Zukowski for more information.

Given your example, the last line would be as following using BigDecimal.

import java.math.BigDecimal;

BigDecimal premium = BigDecimal.valueOf("1586.6");
BigDecimal netToCompany = BigDecimal.valueOf("708.75");
BigDecimal commission = premium.subtract(netToCompany);
System.out.println(commission + " = " + premium + " - " + netToCompany);

This results in the following output.

877.85 = 1586.6 - 708.75

Get current date in DD-Mon-YYY format in JavaScript/Jquery

var date = new Date();

console.log(date.toJSON().slice(0,10).replace(new RegExp("-", 'g'),"/" ).split("/").reverse().join("/")+" "+date.toJSON().slice(11,19));

// output : 01/09/2016 18:30:00

Hiding an Excel worksheet with VBA

I would like to answer your question, as there are various methods - here I’ll talk about the code that is widely used.

So, for hiding the sheet:

Sub try()
    Worksheets("Sheet1").Visible = xlSheetHidden
End Sub

There are other methods also if you want to learn all Methods Click here

"Find next" in Vim

If you press Ctrl + Enter after you press something like "/wordforsearch", then you can find the word "wordforsearch" in the current line. Then press n for the next match; press N for previous match.

What are the differences between normal and slim package of jquery?

At this time, the most authoritative answer appears to be in this issue, which states "it is a custom build of jQuery that excludes effects, ajax, and deprecated code." Details will be announced with jQuery 3.0.

I suspect that the rationale for excluding these components of the jQuery library is in recognition of the increasingly common scenario of jQuery being used in conjunction with another JS framework like Angular or React. In these cases, the usage of jQuery is primarily for DOM traversal and manipulation, so leaving out those components that are either obsolete or are provided by the framework gains about a 20% reduction in file size.

Creating a simple XML file using python

These days, the most popular (and very simple) option is the ElementTree API, which has been included in the standard library since Python 2.5.

The available options for that are:

  • ElementTree (Basic, pure-Python implementation of ElementTree. Part of the standard library since 2.5)
  • cElementTree (Optimized C implementation of ElementTree. Also offered in the standard library since 2.5)
  • LXML (Based on libxml2. Offers a rich superset of the ElementTree API as well XPath, CSS Selectors, and more)

Here's an example of how to generate your example document using the in-stdlib cElementTree:

import xml.etree.cElementTree as ET

root = ET.Element("root")
doc = ET.SubElement(root, "doc")

ET.SubElement(doc, "field1", name="blah").text = "some value1"
ET.SubElement(doc, "field2", name="asdfasd").text = "some vlaue2"

tree = ET.ElementTree(root)
tree.write("filename.xml")

I've tested it and it works, but I'm assuming whitespace isn't significant. If you need "prettyprint" indentation, let me know and I'll look up how to do that. (It may be an LXML-specific option. I don't use the stdlib implementation much)

For further reading, here are some useful links:

As a final note, either cElementTree or LXML should be fast enough for all your needs (both are optimized C code), but in the event you're in a situation where you need to squeeze out every last bit of performance, the benchmarks on the LXML site indicate that:

  • LXML clearly wins for serializing (generating) XML
  • As a side-effect of implementing proper parent traversal, LXML is a bit slower than cElementTree for parsing.

Is there an easy way to reload css without reloading the page?

Since this question was shown in the stackoverflow in 2019, I'd like to add my contribution using a more modern JavaScript.

Specifically, for CSS Stylesheet that are not inline – since that is already covered from the original question, somehow.

First of all, notice that we still don't have Constructable Stylesheet Objects. However, we hope to have them landed soon.

In the meantime, assuming the following HTML content:

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8" />
    <link id="theme" rel="stylesheet" type="text/css" href="./index.css" />
    <script src="./index.js"></script>
  </head>
  <body>
    <p>Hello World</p>
    <button onclick="reload('theme')">Reload</button>
  </body>
</html>

We could have, in index.js:

// Utility function to generate a promise that is 
// resolved when the `target` resource is loaded,
// and rejected if it fails to load.
//
const load = target =>
  new Promise((rs, rj) => {
    target.addEventListener("load", rs, { once: true });
    target.addEventListener(
      "error",
      rj.bind(null, `Can't load ${target.href}`),
      { once: true }
    );
  });


// Here the reload function called by the button.
// It takes an `id` of the stylesheet that needs to be reloaded
async function reload(id) {
  const link = document.getElementById(id);

  if (!link || !link.href) {
    throw new Error(`Can't reload '${id}', element or href attribute missing.`);
  }

  // Here the relevant part.
  // We're fetching the stylesheet from the server, specifying `reload`
  // as cache setting, since that is our intention.
  // With `reload`, the browser fetches the resource *without* first looking
  // in the cache, but then will update the cache with the downloaded resource.
  // So any other pages that request the same file and hit the cache first,
  // will use the updated version instead of the old ones.
  let response = await fetch(link.href, { cache: "reload" });

  // Once we fetched the stylesheet and replaced in the cache,
  // We want also to replace it in the document, so we're
  // creating a URL from the response's blob:
  let url = await URL.createObjectURL(await response.blob());

  // Then, we create another `<link>` element to display the updated style,
  // linked to the original one; but only if we didn't create previously:
  let updated = document.querySelector(`[data-link-id=${id}]`);

  if (!updated) {
    updated = document.createElement("link");
    updated.rel = "stylesheet";
    updated.type = "text/css";
    updated.dataset.linkId = id;
    link.parentElement.insertBefore(updated, link);

    // At this point we disable the original stylesheet,
    // so it won't be applied to the document anymore.
    link.disabled = true;
  }

  // We set the new <link> href...
  updated.href = url;

  // ...Waiting that is loaded...
  await load(updated);

  // ...and finally tell to the browser that we don't need
  // the blob's URL anymore, so it can be released.
  URL.revokeObjectURL(url);
}

How do I auto-resize an image to fit a 'div' container?

U use the following class to solve this problem;

.custom-image{height: auto; width: auto; max-height: 100%; max-width: 100%; object-fit: contain;}

How do I install TensorFlow's tensorboard?

you may have installed tensorflow to virtualenv. activate it and tensorboard command will become available.

How can I center text (horizontally and vertically) inside a div block?

Adjusting line height to get the vertical alignment.

line-height: 90px;

htaccess redirect to https://www

If you are using CloudFlare or a similar CDN you will get an infinite loop error with the %{HTTPS} solutions provided here. If you're a CloudFlare user you'll need to use this:

RewriteEngine On
RewriteCond %{HTTP:X-Forwarded-Proto} =http
RewriteRule ^ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

How does python numpy.where() work?

How do they achieve internally that you are able to pass something like x > 5 into a method?

The short answer is that they don't.

Any sort of logical operation on a numpy array returns a boolean array. (i.e. __gt__, __lt__, etc all return boolean arrays where the given condition is true).

E.g.

x = np.arange(9).reshape(3,3)
print x > 5

yields:

array([[False, False, False],
       [False, False, False],
       [ True,  True,  True]], dtype=bool)

This is the same reason why something like if x > 5: raises a ValueError if x is a numpy array. It's an array of True/False values, not a single value.

Furthermore, numpy arrays can be indexed by boolean arrays. E.g. x[x>5] yields [6 7 8], in this case.

Honestly, it's fairly rare that you actually need numpy.where but it just returns the indicies where a boolean array is True. Usually you can do what you need with simple boolean indexing.

Select single item from a list

Use the FirstOrDefault selector.

var list = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

var firstEven = list.FirstOrDefault(n => n % 2 == 0);

if (firstEven == 0)
    Console.WriteLine("no even number");
else 
    Console.WriteLine("first even number is {0}", firstEven);

Just pass in a predicate to the First or FirstOrDefault method and it'll happily go round' the list and picks the first match for you.

If there isn't a match, FirstOrDefault will returns the default value of whatever datatype the list items is.

Hope this helps :-)

$(document).click() not working correctly on iPhone. jquery

CSS Cursor:Pointer; is a great solution. FastClick https://github.com/ftlabs/fastclick is another solution which doesn't require you to change css if you didn't want Cursor:Pointer; on an element for some reason. I use fastclick now anyway to eliminate the 300ms delay on iOS devices.

How can I implement custom Action Bar with custom buttons in Android?

Please write following code in menu.xml file:

<menu xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:my_menu_tutorial_app="http://schemas.android.com/apk/res-auto"
      xmlns:tools="http://schemas.android.com/tools"
      tools:context="com.example.mymenus.menu_app.MainActivity">
<item android:id="@+id/item_one"
      android:icon="@drawable/menu_icon"
      android:orderInCategory="l01"
      android:title="Item One"
      my_menu_tutorial_app:showAsAction="always">
      <!--sub-menu-->
      <menu>
          <item android:id="@+id/sub_one"
                android:title="Sub-menu item one" />
          <item android:id="@+id/sub_two"
                android:title="Sub-menu item two" />
      </menu>

Also write this java code in activity class file:

public boolean onOptionsItemSelected(MenuItem item)
{
    super.onOptionsItemSelected(item);
    Toast.makeText(this, "Menus item selected: " +
        item.getTitle(), Toast.LENGTH_SHORT).show();
    switch (item.getItemId())
    {
        case R.id.sub_one:
            isItemOneSelected = true;
            supportInvalidateOptionsMenu();
            return true;
        case MENU_ITEM + 1:
            isRemoveItem = true;
            supportInvalidateOptionsMenu();
            return true;
        default:
            return false;
    }
}

This is the easiest way to display menus in action bar.

Convert seconds to HH-MM-SS with JavaScript?

Try this:

function toTimeString(seconds) {
  return (new Date(seconds * 1000)).toUTCString().match(/(\d\d:\d\d:\d\d)/)[0];
}