How does @synchronized lock/unlock in Objective-C?

It just associates a semaphore with every object, and uses that.

How to render an ASP.NET MVC view as a string?

To repeat from a more unknown question, take a look at MvcIntegrationTestFramework.

It makes saves you writing your own helpers to stream result and is proven to work well enough. I'd assume this would be in a test project and as a bonus you would have the other testing capabilities once you've got this setup. Main bother would probably be sorting out the dependency chain.

 private static readonly string mvcAppPath = 
     Path.GetFullPath(AppDomain.CurrentDomain.BaseDirectory 
     + "\\..\\..\\..\\MyMvcApplication");
 private readonly AppHost appHost = new AppHost(mvcAppPath);

    [Test]
    public void Root_Url_Renders_Index_View()
    {
        appHost.SimulateBrowsingSession(browsingSession => {
            RequestResult result = browsingSession.ProcessRequest("");
            Assert.IsTrue(result.ResponseText.Contains("<!DOCTYPE html"));
        });
}

SQL Server equivalent to Oracle's CREATE OR REPLACE VIEW

As of SQL Server 2016 you have

DROP TABLE IF EXISTS [foo];

MSDN source

Android Studio and Gradle build error

If you are using the Gradle Wrapper (the recommended option in Android Studio), you enable stacktrace by running gradlew compileDebug --stacktrace from the command line in the root folder of your project (where the gradlew file is).

If you are not using the gradle wrapper, you use gradle compileDebug --stacktrace instead (presumably).

You don't really need to run with --stacktrace though, running gradlew compileDebug by itself, from the command line, should tell you where the error is.

I based this information on this comment:

Android Studio new project can not run, throwing error

How to do multiline shell script in Ansible

https://support.ansible.com/hc/en-us/articles/201957837-How-do-I-split-an-action-into-a-multi-line-format-

mentions YAML line continuations.

As an example (tried with ansible 2.0.0.2):

---
- hosts: all
  tasks:
    - name: multiline shell command
      shell: >
        ls --color
        /home
      register: stdout

    - name: debug output
      debug: msg={{ stdout }}

The shell command is collapsed into a single line, as in ls --color /home

Adb over wireless without usb cable at all for not rooted phones

Connect android phone without using USB cable except XIAOMI PHONES
== MAKE SURE THAT YOUR PHONE HAS USB DEBUGGING ENABLED ==
== IP Address series should NOT be '0' like 192.168.0.10
1. Connect your PC (Laptop) and Android phone to same wifi network.
2. Go to the Android SDK folder > platform-tools and open command prompt by holding the shift key and right clicking on the folder.
3. Type the command "adb tcpip 5555", and hit Enter, sometimes it gives an error but ignore it and go ahead.
4. Type "adb connect [YOUR PHONE IP]". example: "adb connect 192.168.1.34" and hit enter, your phone will be connected to PC.

What can cause a “Resource temporarily unavailable” on sock send() command

Let'e me give an example:

client connect to server, and send 1MB data to server every 1 second.
server side accept a connection, and then sleep 20 second, without recv msg from client.So the tcp send buffer in the client side will be full.

Code in client side:

#include <arpa/inet.h>
#include <sys/socket.h>
#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#define exit_if(r, ...)                                                                          \
    if (r) {                                                                                     \
        printf(__VA_ARGS__);                                                                     \
        printf("%s:%d error no: %d error msg %s\n", __FILE__, __LINE__, errno, strerror(errno)); \
        exit(1);                                                                                 \
    }

void setNonBlock(int fd) {
    int flags = fcntl(fd, F_GETFL, 0);
    exit_if(flags < 0, "fcntl failed");
    int r = fcntl(fd, F_SETFL, flags | O_NONBLOCK);
    exit_if(r < 0, "fcntl failed");
}

void test_full_sock_buf_1(){
    short port = 8000;
    struct sockaddr_in addr;
    memset(&addr, 0, sizeof addr);
    addr.sin_family = AF_INET;
    addr.sin_port = htons(port);
    addr.sin_addr.s_addr = INADDR_ANY;


    int fd = socket(AF_INET, SOCK_STREAM, 0);
    exit_if(fd<0, "create socket error");

    int ret = connect(fd, (struct sockaddr *) &addr, sizeof(struct sockaddr));
    exit_if(ret<0, "connect to server error");
    setNonBlock(fd);

    printf("connect to server success");

    const int LEN = 1024 * 1000;
    char msg[LEN];  // 1MB data
    memset(msg, 'a', LEN);

    for (int i = 0; i < 1000; ++i) {
        int len = send(fd, msg, LEN, 0);
        printf("send: %d, erron: %d, %s \n", len, errno, strerror(errno));
        sleep(1);
    }

}

int main(){
    test_full_sock_buf_1();

    return 0;
}

Code in server side:

    #include <arpa/inet.h>
    #include <sys/socket.h>
    #include <stdio.h>
    #include <errno.h>
    #include <fcntl.h>
    #include <stdlib.h>
    #include <string.h>
    #define exit_if(r, ...)                                                                          \
        if (r) {                                                                                     \
            printf(__VA_ARGS__);                                                                     \
            printf("%s:%d error no: %d error msg %s\n", __FILE__, __LINE__, errno, strerror(errno)); \
            exit(1);                                                                                 \
        }
void test_full_sock_buf_1(){

    int listenfd = socket(AF_INET, SOCK_STREAM, 0);
    exit_if(listenfd<0, "create socket error");

    short port = 8000;
    struct sockaddr_in addr;
    memset(&addr, 0, sizeof addr);
    addr.sin_family = AF_INET;
    addr.sin_port = htons(port);
    addr.sin_addr.s_addr = INADDR_ANY;

    int r = ::bind(listenfd, (struct sockaddr *) &addr, sizeof(struct sockaddr));
    exit_if(r<0, "bind socket error");

    r = listen(listenfd, 100);
    exit_if(r<0, "listen socket error");

    struct sockaddr_in raddr;
    socklen_t rsz = sizeof(raddr);
    int cfd = accept(listenfd, (struct sockaddr *) &raddr, &rsz);
    exit_if(cfd<0, "accept socket error");

    sockaddr_in peer;
    socklen_t alen = sizeof(peer);
    getpeername(cfd, (sockaddr *) &peer, &alen);

    printf("accept a connection from %s:%d\n", inet_ntoa(peer.sin_addr), ntohs(peer.sin_port));

    printf("but now I will sleep 15 second, then exit");
    sleep(15);
}

Start server side, then start client side.

server side may output:

accept a connection from 127.0.0.1:35764
but now I will sleep 15 second, then exit
Process finished with exit code 0

client side may output:

connect to server successsend: 1024000, erron: 0, Success 
send: 1024000, erron: 0, Success 
send: 1024000, erron: 0, Success 
send: 552190, erron: 0, Success 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 104, Connection reset by peer 
send: -1, erron: 32, Broken pipe 
send: -1, erron: 32, Broken pipe 
send: -1, erron: 32, Broken pipe 
send: -1, erron: 32, Broken pipe 
send: -1, erron: 32, Broken pipe

You can see, as the server side doesn't recv the data from client, so when the client side tcp buffer get full, but you still send data, so you may get Resource temporarily unavailable error.

Could not find or load main class org.gradle.wrapper.GradleWrapperMain

if it's a new project, remove existing folder and run $ npm install -g react-native-cli

check that runs without any error

Initializing a struct to 0

I also thought this would work but it's misleading:

myStruct _m1 = {0};

When I tried this:

myStruct _m1 = {0xff};

Only the 1st byte was set to 0xff, the remaining ones were set to 0. So I wouldn't get into the habit of using this.

Unsupported major.minor version 52.0 when rendering in Android Studio

I had to update Java version to JDK 8 at Jenkins->Manage Jenkins->Global Tool Configuration->JDK.

Select all text inside EditText when it gets focus

I know you've found a solution, but really the proper way to do what you're asking is to just use the android:hint attribute in your EditText. This text shows up when the box is empty and not focused, but disappears upon selecting the EditText box.

Java: notify() vs. notifyAll() all over again

While there are some solid answers above, I am surprised by the number of confusions and misunderstandings I have read. This probably proves the idea that one should use java.util.concurrent as much as possible instead of trying to write their own broken concurrent code.

Back to the question: to summarize, the best practice today is to AVOID notify() in ALL situations due to the lost wakeup problem. Anyone who doesn't understand this should not be allowed to write mission critical concurrency code. If you are worried about the herding problem, one safe way to achieve waking one thread up at a time is to:

Build an explicit waiting queue for the waiting threads;
Have each of the thread in the queue wait for its predecessor;
Have each thread call notifyAll() when done.

Or you can use Java.util.concurrent.*, which have already implemented this.

How to open an external file from HTML

Your first idea used to be the way but I've also noticed issues doing this using Firefox, try a straight http:// to the file - href='http://server/directory/file.xlsx'

Add / Change parameter of URL and redirect to the new URL

though i take the url from an input, it's easy adjustable to the real url.

var value = 0;

$('#check').click(function()
{
    var originalURL = $('#test').val();
    var exists = originalURL.indexOf('&view-all');

    if(exists === -1)
    {
        $('#test').val(originalURL + '&view-all=value' + value++);
    }
    else
    {
        $('#test').val(originalURL.substr(0, exists + 15) + value++);
    }
});

http://jsfiddle.net/8YPh9/31/

Can I set enum start value in Java?

 public class MyClass {
    public static void main(String args[]) {
     Ids id1 = Ids.OPEN;
     System.out.println(id1.getValue());
    }
}

enum Ids {
    OPEN(100), CLOSE(200);

    private final int id;
    Ids(int id) { this.id = id; }
    public int getValue() { return id; }
}

@scottf, You probably confused because of the constructor defined in the ENUM.

Let me explain that.

When class loader loads enum class, then enum constructor also called. On what!! Yes, It's called on OPEN and close. With what values 100 for OPEN and 200 for close

Can I have different value?

Yes,

public class MyClass {
    public static void main(String args[]) {
     Ids id1 = Ids.OPEN;
     id1.setValue(2);
     System.out.println(id1.getValue());
    }
}

enum Ids {
    OPEN(100), CLOSE(200);

    private int id;
    Ids(int id) { this.id = id; }
    public int getValue() { return id; }
    public void setValue(int value) { id = value; }
}

But, It's bad practice. enum is used for representing constants like days of week, colors in rainbow i.e such small group of predefined constants.

Android camera android.hardware.Camera deprecated

Now we have to use android.hardware.camera2 as android.hardware.Camera is deprecated which will only work on API >23 FlashLight

   public class MainActivity extends AppCompatActivity {

     Button button;

     Boolean light=true;

     CameraDevice cameraDevice;

     private CameraManager cameraManager;

     private CameraCharacteristics cameraCharacteristics;

     String cameraId;

     @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        button=(Button)findViewById(R.id.button);
        cameraManager = (CameraManager) 
        getSystemService(Context.CAMERA_SERVICE);
        try {
          cameraId = cameraManager.getCameraIdList()[0];
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(light){
                    try {

                        cameraManager.setTorchMode(cameraId,true);
                    } catch (CameraAccessException e) {
                        e.printStackTrace();
                    }

                    light=false;}
                    else {

                    try {

                      cameraManager.setTorchMode(cameraId,false);
                    } catch (CameraAccessException e) {
                        e.printStackTrace();
                    }


                    light=true;
                    }


            }
        });
    }
}

How to Compare a long value is equal to Long value

First your code is not compiled. Line Long b = 1113;

is wrong. You have to say

Long b = 1113L;

Second when I fixed this compilation problem the code printed "not equals".

How to set a CMake option() at command line

Delete the CMakeCache.txt file and try this:

cmake -G %1 -DBUILD_SHARED_LIBS=ON -DBUILD_STATIC_LIBS=ON -DBUILD_TESTS=ON ..

You have to enter all your command-line definitions before including the path.

Include jQuery in the JavaScript Console

intuitive one-liner

document.write(unescape('%3Cscript src="https://code.jquery.com/jquery-3.1.1.min.js"%3E%3C/script%3E’))

You can change the src address.
I referred to ReferenceError: Can't find variable: jQuery

Python set to list

Try using combination of map and lambda functions:

aList = map( lambda x: x, set ([1, 2, 6, 9, 0]) )

It is very convenient approach if you have a set of numbers in string and you want to convert it to list of integers:

aList = map( lambda x: int(x), set (['1', '2', '3', '7', '12']) )

select dept names who have more than 2 employees whose salary is greater than 1000

1:list name of all employee who earn more than RS.100000 in a year.

2:give the name of employee who earn heads the department where employee with employee I.D

How to get first 5 characters from string

Use substr():

$result = substr($myStr, 0, 5);

What is a stack trace, and how can I use it to debug my application errors?

To understand the name: A stack trace is a a list of Exceptions( or you can say a list of "Cause by"), from the most surface Exception(e.g. Service Layer Exception) to the deepest one (e.g. Database Exception). Just like the reason we call it 'stack' is because stack is First in Last out (FILO), the deepest exception was happened in the very beginning, then a chain of exception was generated a series of consequences, the surface Exception was the last one happened in time, but we see it in the first place.

Key 1:A tricky and important thing here need to be understand is : the deepest cause may not be the "root cause", because if you write some "bad code", it may cause some exception underneath which is deeper than its layer. For example, a bad sql query may cause SQLServerException connection reset in the bottem instead of syndax error, which may just in the middle of the stack.

-> Locate the root cause in the middle is your job.

Key 2:Another tricky but important thing is inside each "Cause by" block, the first line was the deepest layer and happen first place for this block. For instance,

Exception in thread "main" java.lang.NullPointerException
        at com.example.myproject.Book.getTitle(Book.java:16)
           at com.example.myproject.Author.getBookTitles(Author.java:25)
               at com.example.myproject.Bootstrap.main(Bootstrap.java:14)

Book.java:16 was called by Auther.java:25 which was called by Bootstrap.java:14, Book.java:16 was the root cause. Here attach a diagram sort the trace stack in chronological order.

Undefined symbols for architecture armv7

I didn't find this suggestion here so here it goes: if your project has more than one target (ie one for OSX and one for iOS) then you must link the relevant libraries for each target.. so for example in my case I needed AudioToolbox.. I had to add it once for OSX and once for iOS (under the frameworks folder, you must have a duplicate of each library for each target.. if you see only one.. then that's a red flag)

How to fix "Only one expression can be specified in the select list when the subquery is not introduced with EXISTS" error?

Try this one -

"SELECT 
       ID, Salt, password, BannedEndDate
     , (
          SELECT COUNT(1)
          FROM dbo.LoginFails l
          WHERE l.UserName = u.UserName
               AND IP = '" + Request.ServerVariables["REMOTE_ADDR"] + "'
      ) AS cnt
FROM dbo.Users u
WHERE u.UserName = '" + LoginModel.Username + "'"

How to change the DataTable Column Name?

Rename the Column by doing the following:

dataTable.Columns["ColumnName"].ColumnName = "newColumnName";

tr:hover not working

I had the same problem. I found that if I use a DOCTYPE like:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">

it didn't work. But if I use:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN">

it did work.

Indexes of all occurrences of character in a string

Also, if u want to find all indexes of a String in a String.

int index = word.indexOf(guess);
while (index >= 0) {
    System.out.println(index);
    index = word.indexOf(guess, index + guess.length());
}

Convert Json string to Json object in Swift 4

I used below code and it's working fine for me. :

let jsonText = "{\"userName\":\"Bhavsang\"}"
var dictonary:NSDictionary?
    
if let data = jsonText.dataUsingEncoding(NSUTF8StringEncoding) {
        
     do {
            dictonary =  try NSJSONSerialization.JSONObjectWithData(data, options: [.allowFragments]) as? [String:AnyObject]
        
            if let myDictionary = dictonary
              {
                  print(" User name is: \(myDictionary["userName"]!)")
              }
            } catch let error as NSError {
            
            print(error)
         }
}

Difference between Relative path and absolute path in javascript

The path with reference to root directory is called absolute. The path with reference to current directory is called relative.

SPAN vs DIV (inline-block)

If you want to have a valid xhtml document then you cannot put a div inside of a paragraph.

Also, a div with the property display: inline-block works differently than a span. A span is by default an inline element, you cannot set the width, height, and other properties associated with blocks. On the other hand, an element with the property inline-block will still "flow" with any surrounding text but you may set properties such as width, height, etc. A span with the property display:block will not flow in the same way as an inline-block element but will create a carriage return and have default margin.

Note that inline-block is not supported in all browsers. For instance in Firefox 2 and less you must use:

display: -moz-inline-stack;

which displays slightly different than an inline block element in FF3.

There is a great article here on creating cross browser inline-block elements.

warning: control reaches end of non-void function [-Wreturn-type]

You can also use EXIT_SUCCESS instead of return 0;. The macro EXIT_SUCCESS is actually defined as zero, but makes your program more readable.

How to execute INSERT statement using JdbcTemplate class from Spring Framework

we can use update for both insert and update/delte

MsgBox "" vs MsgBox() in VBScript

You have to distinct sub routines and functions in vba... Generally (as far as I know), sub routines do not return anything and the surrounding parantheses are optional. For functions, you need to write the parantheses.

As for your example, MsgBox is not a function but a sub routine and therefore the parantheses are optional in that case. One exception with functions is, when you do not assign the returned value, or when the function does not consume a parameter, you can leave away the parantheses too.

This answer goes into a bit more detail, but basically you should be on the save side, when you provide parantheses for functions and leave them away for sub routines.

.htaccess rewrite subdomain to directory

For any sub domain request, use this:

RewriteEngine on 
RewriteCond %{HTTP_HOST} !^www\.band\.s\.co 
RewriteCond %{HTTP_HOST} ^(.*)\.band\.s\.co 
RewriteCond %{REQUEST_URI} !^/([a-zA-Z0-9-z\-]+) 
RewriteRule ^(.*)$ /%1/$1 [L]

Just make some folder same as sub domain name you need. Folder must be exist like this: domain.com/sub for sub.domain.com.

Reference — What does this symbol mean in PHP?

== is used for check equality without considering variable data-type

=== is used for check equality for both the variable value and data-type

Example

$a = 5

if ($a == 5) - will evaluate to true
if ($a == '5') - will evaluate to true, because while comparing this both value PHP internally convert that string value into integer and then compare both values
if ($a === 5) - will evaluate to true
if ($a === '5') - will evaluate to false, because value is 5, but this value 5 is not an integer.

Bootstrap - 5 column layout

What about using offset?

<div class="row">
  <div class="col-sm-8 offset-sm-2 col-lg-2 offset-lg-1">
    1
  </div>
  <div class="col-sm-8 offset-sm-2 col-lg-2 offset-lg-0">
    2
  </div>
  <div class="col-sm-8 offset-sm-2 col-lg-2 offset-lg-0">
    3
  </div>
  <div class="col-sm-8 offset-sm-2 col-lg-2 offset-lg-0">
    4
  </div>
  <div class="col-sm-8 offset-sm-2 col-lg-2 offset-lg-0">
    5
  </div>
</div>

WPF User Control Parent

I needed to use the Window.GetWindow(this) method within Loaded event handler. In other words, I used both Ian Oakes' answer in combination with Alex's answer to get a user control's parent.

public MainView()
{
    InitializeComponent();

    this.Loaded += new RoutedEventHandler(MainView_Loaded);
}

void MainView_Loaded(object sender, RoutedEventArgs e)
{
    Window parentWindow = Window.GetWindow(this);

    ...
}

How to search for rows containing a substring?

Well, you can always try WHERE textcolumn LIKE "%SUBSTRING%" - but this is guaranteed to be pretty slow, as your query can't do an index match because you are looking for characters on the left side.

It depends on the field type - a textarea usually won't be saved as VARCHAR, but rather as (a kind of) TEXT field, so you can use the MATCH AGAINST operator.

To get the columns that don't match, simply put a NOT in front of the like: WHERE textcolumn NOT LIKE "%SUBSTRING%".

Whether the search is case-sensitive or not depends on how you stock the data, especially what COLLATION you use. By default, the search will be case-insensitive.

Updated answer to reflect question update:

I say that doing a WHERE field LIKE "%value%" is slower than WHERE field LIKE "value%" if the column field has an index, but this is still considerably faster than getting all values and having your application filter. Both scenario's:

1/ If you do SELECT field FROM table WHERE field LIKE "%value%", MySQL will scan the entire table, and only send the fields containing "value".

2/ If you do SELECT field FROM table and then have your application (in your case PHP) filter only the rows with "value" in it, MySQL will also scan the entire table, but send all the fields to PHP, which then has to do additional work. This is much slower than case #1.

Solution: Please do use the WHERE clause, and use EXPLAIN to see the performance.

What are Maven goals and phases and what is their difference?

Credit to Sandeep Jindal and Premraj. Their explanation help me to understand after confused about this for a while.

I created some full code examples & some simple explanations here https://www.surasint.com/maven-life-cycle-phase-and-goal-easy-explained/ . I think it may help others to understand.

In short from the link, You should not try to understand all three at once, first you should understand the relationship in these groups:

Life Cycle vs Phase
Plugin vs Goal

1. Life Cycle vs Phase

Life Cycle is a collection of phase in sequence see here Life Cycle References. When you call a phase, it will also call all phase before it.

For example, the clean life cycle has 3 phases (pre-clean, clean, post-clean).

mvn clean

It will call pre-clean and clean.

2. Plugin vs Goal

Goal is like an action in Plugin. So if plugin is a class, goal is a method.

you can call a goal like this:

mvn clean:clean

This means "call the clean goal, in the clean plugin" (Nothing relates to the clean phase here. Don't let the word"clean" confusing you, they are not the same!)

3. Now the relation between Phase & Goal:

Phase can (pre)links to Goal(s).For example, normally, the clean phase links to the clean goal. So, when you call this command:

mvn clean

It will call the pre-clean phase and the clean phase which links to the clean:clean goal.

It is almost the same as:

mvn pre-clean clean:clean

More detail and full examples are in https://www.surasint.com/maven-life-cycle-phase-and-goal-easy-explained/

tar: file changed as we read it

It worked for me by adding a simple sleep timeout of 20 sec. This might happen if your source directory is still writing. Hence put a sleep so that the backup would finish and then tar should work fine. This also helped me in getting the right exit status.

sleep 20
tar -czf ${DB}.${DATE}.tgz ./${DB}.${DATE}

Mysql service is missing

If you wish to have your config file on a different path you have to give your service a name:

mysqld --install NAME --defaults-file=C:\my-opts2.cnf

You can also use the name to install multiple mysql services listening on different sockets if you need that for some reason. You can see why it's failing by copying the execution path and adding --console to the end in the terminal. Finally, you can modify the starting path of a service by regediting:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\NAME

That works well but it isn't as useful because the windows service mechanism provides little logging capabilities.

jQuery keypress() event not firing?

Ofcourse this is a closed issue, i would like to add something to your discussion

In mozilla i have observed a weird behaviour for this code

$(document).keydown(function(){
//my code 
});

the code is being triggered twice. When debugged i found that actually there are two events getting fired: 'keypress' and 'keydown'. I disabled one of the event and the code shown me expected behavior.

$(document).unbind('keypress');
$(document).keydown(function(){
//my code
});

This works for all browsers and also there is no need to check for browser specific(if($.browser.mozilla){ }).

Hope this might be useful for someone

What is JAVA_HOME? How does the JVM find the javac path stored in JAVA_HOME?

use this command /usr/libexec/java_home to check the JAVA_HOME

Advantage of switch over if-else statement

Im not the person to tell you about speed and memory usage, but looking at a switch statment is a hell of a lot easier to understand then a large if statement (especially 2-3 months down the line)

Signed to unsigned conversion in C - is it always safe?

Short Answer

Your i will be converted to an unsigned integer by adding UINT_MAX + 1, then the addition will be carried out with the unsigned values, resulting in a large result (depending on the values of u and i).

Long Answer

According to the C99 Standard:

6.3.1.8 Usual arithmetic conversions

If both operands have the same type, then no further conversion is needed.

Otherwise, if both operands have signed integer types or both have unsigned integer types, the operand with the type of lesser integer conversion rank is converted to the type of the operand with greater rank.

Otherwise, if the operand that has unsigned integer type has rank greater or equal to the rank of the type of the other operand, then the operand with signed integer type is converted to the type of the operand with unsigned integer type.

Otherwise, if the type of the operand with signed integer type can represent all of the values of the type of the operand with unsigned integer type, then the operand with unsigned integer type is converted to the type of the operand with signed integer type.

Otherwise, both operands are converted to the unsigned integer type corresponding to the type of the operand with signed integer type.

In your case, we have one unsigned int (u) and signed int (i). Referring to (3) above, since both operands have the same rank, your i will need to be converted to an unsigned integer.

6.3.1.3 Signed and unsigned integers

When a value with integer type is converted to another integer type other than _Bool, if the value can be represented by the new type, it is unchanged.

Otherwise, if the new type is unsigned, the value is converted by repeatedly adding or subtracting one more than the maximum value that can be represented in the new type until the value is in the range of the new type.

Otherwise, the new type is signed and the value cannot be represented in it; either the result is implementation-defined or an implementation-defined signal is raised.

Now we need to refer to (2) above. Your i will be converted to an unsigned value by adding UINT_MAX + 1. So the result will depend on how UINT_MAX is defined on your implementation. It will be large, but it will not overflow, because:

6.2.5 (9)

A computation involving unsigned operands can never overflow, because a result that cannot be represented by the resulting unsigned integer type is reduced modulo the number that is one greater than the largest value that can be represented by the resulting type.

Bonus: Arithmetic Conversion Semi-WTF

#include <stdio.h>

int main(void)
{
  unsigned int plus_one = 1;
  int minus_one = -1;

  if(plus_one < minus_one)
    printf("1 < -1");
  else
    printf("boring");

  return 0;
}

You can use this link to try this online: https://repl.it/repls/QuickWhimsicalBytes

Bonus: Arithmetic Conversion Side Effect

Arithmetic conversion rules can be used to get the value of UINT_MAX by initializing an unsigned value to -1, ie:

unsigned int umax = -1; // umax set to UINT_MAX

This is guaranteed to be portable regardless of the signed number representation of the system because of the conversion rules described above. See this SO question for more information: Is it safe to use -1 to set all bits to true?

How to truncate text in Angular2?

Just tried @Timothy Perez answer and added a line

if (value.length < limit)
   return `${value.substr(0, limit)}`;

import { Pipe, PipeTransform } from '@angular/core';

@Pipe({
  name: 'truncate'
})
export class TruncatePipe implements PipeTransform {
transform(value: string, limit = 25, completeWords = false, ellipsis = '...') {

   if (value.length < limit)
   return `${value.substr(0, limit)}`;

   if (completeWords) {
     limit = value.substr(0, limit).lastIndexOf(' ');
   }
   return `${value.substr(0, limit)}${ellipsis}`;
}
}

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

mysql_ping

better way to drop nan rows in pandas

Just in case commands in previous answers doesn't work, Try this: dat.dropna(subset=['x'], inplace = True)

How to pause a vbscript execution?

You can use a WScript object and call the Sleep method on it:

Set WScript = CreateObject("WScript.Shell")
WScript.Sleep 2000 'Sleeps for 2 seconds

Another option is to import and use the WinAPI function directly (only works in VBA, thanks @Helen):

Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long)
Sleep 2000

Turn Pandas Multi-Index into column

As @cs95 mentioned in a comment, to drop only one level, use:

df.reset_index(level=[...])

This avoids having to redefine your desired index after reset.

Entity Framework: "Store update, insert, or delete statement affected an unexpected number of rows (0)."

Recently, I'm trying upgrade EF5 to EF6 sample project . The table of sample project has decimal(5,2) type columns. Database migration successfully completed. But, initial data seed generated exception.

Model :

    public partial class Weather
    {
    ...
    public decimal TMax {get;set;}
    public decimal TMin {get;set;}
    ...
    }

Wrong Configuration :

public partial class WeatherMap : EntityTypeConfiguration<Weather>
{

    public WeatherMap()
    {
        ...
        this.Property(t => t.TMax).HasColumnName("TMax");
        this.Property(t => t.TMin).HasColumnName("TMin");
        ...
    }
}

Data :

    internal static Weather[] data = new Weather[365]
    {
      new Weather() {...,TMax = 3.30M,TMin = -12.00M,...},
      new Weather() {...,TMax = 5.20M,TMin = -10.00M,...},
      new Weather() {...,TMax = 3.20M,TMin = -8.00M,...},
      new Weather() {...,TMax = 11.00M,TMin = -7.00M,...},
      new Weather() {...,TMax = 9.00M,TMin = 0.00M,...},
    };

I found the problem, Seeding data has precision values, but configuration does not have precision and scale parameters. TMax and TMin fields defined with decimal(10,0) in sample table.

Correct Configuration :

public partial class WeatherMap : EntityTypeConfiguration<Weather>
{

    public WeatherMap()
    {
        ...
        this.Property(t => t.TMax).HasPrecision(5,2).HasColumnName("TMax");
        this.Property(t => t.TMin).HasPrecision(5,2).HasColumnName("TMin");
        ...
    }
}

My sample project run with: MySql 5.6.14, Devart.Data.MySql, MVC4, .Net 4.5.1, EF6.01

Best regards.

Laravel PHP Command Not Found

Just use it:

composer create-project --prefer-dist laravel/laravel youprojectname

Swift Alamofire: How to get the HTTP response status code

Best way to get the status code using alamofire.

 Alamofire.request(URL).responseJSON {
  response in

  let status = response.response?.statusCode
  print("STATUS \(status)")

}

How to compare objects by multiple fields

Starting from Steve's answer the ternary operator can be used:

public int compareTo(Person other) {
    int f = firstName.compareTo(other.firstName);
    int l = lastName.compareTo(other.lastName);
    return f != 0 ? f : l != 0 ? l : Integer.compare(age, other.age);
}

Detect backspace and del on "input" event?

Use .onkeydown and cancel the removing with return false;. Like this:

var input = document.getElementById('myInput');

input.onkeydown = function() {
    var key = event.keyCode || event.charCode;

    if( key == 8 || key == 46 )
        return false;
};

Or with jQuery, because you added a jQuery tag to your question:

jQuery(function($) {
  var input = $('#myInput');
  input.on('keydown', function() {
    var key = event.keyCode || event.charCode;

    if( key == 8 || key == 46 )
        return false;
  });
});

python location on mac osx

[GCC 4.2.1 (Apple Inc. build 5646)] is the version of GCC that the Python(s) were built with, not the version of Python itself. That information should be on the previous line. For example:

# Apple-supplied Python 2.6 in OS X 10.6
$ /usr/bin/python
Python 2.6.1 (r261:67515, Jun 24 2010, 21:47:49) 
[GCC 4.2.1 (Apple Inc. build 5646)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> 

# python.org Python 2.7.2 (also built with newer gcc)
$ /usr/local/bin/python
Python 2.7.2 (v2.7.2:8527427914a2, Jun 11 2011, 15:22:34) 
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>

Items in /usr/bin should always be or link to files supplied by Apple in OS X, unless someone has been ill-advisedly changing things there. To see exactly where the /usr/local/bin/python is linked to:

$ ls -l /usr/local/bin/python
lrwxr-xr-x  1 root  wheel  68 Jul  5 10:05 /usr/local/bin/python@ -> ../../../Library/Frameworks/Python.framework/Versions/2.7/bin/python

In this case, that is typical for a python.org installed Python instance or it could be one built from source.

How to increment a variable on a for loop in jinja template?

As Jeroen says there are scoping issues: if you set 'count' outside the loop, you can't modify it inside the loop.

You can defeat this behavior by using an object rather than a scalar for 'count':

{% set count = [1] %}

You can now manipulate count inside a forloop or even an %include%. Here's how I increment count (yes, it's kludgy but oh well):

{% if count.append(count.pop() + 1) %}{% endif %} {# increment count by 1 #}

Refused to execute script, strict MIME type checking is enabled?

Python flask

On Windows, it uses data from the registry, so if the "Content Type" value in HKCR/.js is not set to the proper MIME type it can cause your problem.

Open regedit and go to the HKEY_CLASSES_ROOT make sure the key .js/Content Type has the value text/javascript

C:\>reg query HKCR\.js /v "Content Type"

HKEY_CLASSES_ROOT\.js
    Content Type    REG_SZ    text/javascript

On duplicate key ignore?

Mysql has this handy UPDATE INTO command ;)

edit Looks like they renamed it to REPLACE

REPLACE works exactly like INSERT, except that if an old row in the table has the same value as a new row for a PRIMARY KEY or a UNIQUE index, the old row is deleted before the new row is inserted

SQL Server 2008 Insert with WHILE LOOP

First of all I'd like to say that I 100% agree with John Saunders that you must avoid loops in SQL in most cases especially in production.

But occasionally as a one time thing to populate a table with a hundred records for testing purposes IMHO it's just OK to indulge yourself to use a loop.

For example in your case to populate your table with records with hospital ids between 16 and 100 and make emails and descriptions distinct you could've used

CREATE PROCEDURE populateHospitals
AS
DECLARE @hid INT;
SET @hid=16;
WHILE @hid < 100
BEGIN 
    INSERT hospitals ([Hospital ID], Email, Description) 
    VALUES(@hid, 'user' + LTRIM(STR(@hid)) + '@mail.com', 'Sample Description' + LTRIM(STR(@hid))); 
    SET @hid = @hid + 1;
END

And result would be

ID   Hospital ID Email            Description          
---- ----------- ---------------- ---------------------
1    16          [email protected]  Sample Description16 
2    17          [email protected]  Sample Description17 
...                                                    
84   99          [email protected]  Sample Description99

Remove background drawable programmatically in Android

This work for me:

yourview.setBackground(null);

How do I show the schema of a table in a MySQL database?

SELECT COLUMN_NAME, TABLE_NAME,table_schema
FROM INFORMATION_SCHEMA.COLUMNS;

IF EXISTS in T-SQL

Yes it stops execution so this is generally preferable to HAVING COUNT(*) > 0 which often won't.

With EXISTS if you look at the execution plan you will see that the actual number of rows coming out of table1 will not be more than 1 irrespective of number of matching records.

In some circumstances SQL Server can convert the tree for the COUNT query to the same as the one for EXISTS during the simplification phase (with a semi join and no aggregate operator in sight) an example of that is discussed in the comments here.

For more complicated sub trees than shown in the question you may occasionally find the COUNT performs better than EXISTS however. Because the semi join needs only retrieve one row from the sub tree this can encourage a plan with nested loops for that part of the tree - which may not work out optimal in practice.

How can I convert a file pointer ( FILE* fp ) to a file descriptor (int fd)?

The proper function is int fileno(FILE *stream). It can be found in <stdio.h>, and is a POSIX standard but not standard C.

How to compare oldValues and newValues on React Hooks useEffect?

I just published react-delta which solves this exact sort of scenario. In my opinion, useEffect has too many responsibilities.

Responsibilities

It compares all values in its dependency array using Object.is
It runs effect/cleanup callbacks based on the result of #1

Breaking Up Responsibilities

react-delta breaks useEffect's responsibilities into several smaller hooks.

Responsibility #1

Responsibility #2

useConditionalEffect(callback, boolean)

In my experience, this approach is more flexible, clean, and concise than useEffect/useRef solutions.

How to append elements into a dictionary in Swift?

As of Swift 5, the following code collection works.

 // main dict to start with
 var myDict : Dictionary = [ 1 : "abc", 2 : "cde"]

 // dict(s) to be added to main dict
 let myDictToMergeWith : Dictionary = [ 5 : "l m n"]
 let myDictUpdated : Dictionary = [ 5 : "lmn"]
 let myDictToBeMapped : Dictionary = [ 6 : "opq"]

 myDict[3]="fgh"
 myDict.updateValue("ijk", forKey: 4)

 myDict.merge(myDictToMergeWith){(current, _) in current}
 print(myDict)

 myDict.merge(myDictUpdated){(_, new) in new}
 print(myDict)

 myDictToBeMapped.map {
     myDict[$0.0] = $0.1
 }
 print(myDict)

Change jsp on button click

It works using ajax. The jsp then display in iframe returned by controller in response to request.

function openPage() {
  jQuery.ajax({
  type : 'POST',
  data : jQuery(this).serialize(),
  url : '<%=request.getContextPath()%>/post_action',
  success : function(data, textStatus) {
  jQuery('#iframeId').contents().find('body').append(data);
  },
  error : function(XMLHttpRequest, textStatus, errorThrown) {
  }
  });
}

Pandas dataframe fillna() only some columns in place

Or something like:

df.loc[df['a'].isnull(),'a']=0
df.loc[df['b'].isnull(),'b']=0

and if there is more:

for i in your_list:
    df.loc[df[i].isnull(),i]=0

"RangeError: Maximum call stack size exceeded" Why?

Browsers can't handle that many arguments. See this snippet for example:

alert.apply(window, new Array(1000000000));

This yields RangeError: Maximum call stack size exceeded which is the same as in your problem.

To solve that, do:

var arr = [];
for(var i = 0; i < 1000000; i++){
    arr.push(Math.random());
}

Where to find htdocs in XAMPP Mac

There are two ways to find it:

One way is to open Finder>Applications>XAMPP(FolderNotTheInstaller)>htdocs

Another way is cmd+space and searches for manager-osx,

go to Welcome and click the Open Application Folder.

Windows Task Scheduler doesn't start batch file task

For me, the problem was caused by the .bat included a cd to a network drive. This failed, and then the later call to the program in that network drive did nothing.

I figured this out by adding > log.txt in the Add arguments field of the Edit action window for the task.

Trust Store vs Key Store - creating with keytool

These are the steps to create a Truststore in your local machine using Keytool. Steps to create truststore for a URL in your local machine.

1) Hit the url in the browser using chrome

2) Check for the "i" icon to the left of the url in the chrome and click it

3) Check for certificate option and click it and a Dialog box will open

4) check the "certificate path" tab for the number of certificates available to create the truststore

5) Go the "details" tab -> click"Copy to File" -> Give the path and the name for the certificate you want to create.

6) Check if it has parent certificates and follow the point "5".

7) After all the certificates are being create open Command Prompt and navigate to the path where you created the certificates.

8) provide the below Keytool command to add the certificates and create a truststore.

Sample: 
   keytool -import -alias abcdefg -file abcdefg.cer -keystore cacerts
        where "abcdefg" is the alias name and "abcdefg.cer" is the actual certificate name and "cacerts" is the truststore name

9) Provide the keytool command for all the certificates and add them to the trust store.

    keytool -list -v -keystore cacerts

How can I select rows by range?

You can use rownum :

SELECT * FROM table WHERE rownum > 10 and rownum <= 20

How to get the first element of an array?

@NicoLwk You should remove elements with splice, that will shift your array back. So:

var a=['a','b','c'];
a.splice(0,1);
for(var i in a){console.log(i+' '+a[i]);}

Select elements by attribute

Do you mean can you select them? If so, then yes:

$(":checkbox[myattr]")

Append to the end of a Char array in C++

You should have enough space for array1 array and use something like strcat to contact array1 to array2:

char array1[BIG_ENOUGH];
char array2[X];
/* ......             */
/* check array bounds */
/* ......             */

strcat(array1, array2);

SQL Insert into table only if record doesn't exist

Assuming you cannot modify DDL (to create a unique constraint) or are limited to only being able to write DML then check for a null on filtered result of your values against the whole table

FIDDLE

insert into funds (ID, date, price) 
select 
    T.* 
from 
    (select 23 ID,  '2013-02-12' date,  22.43 price) T  
        left join 
    funds on funds.ID = T.ID and funds.date = T.date
where 
    funds.ID is null

Retrieve column names from java.sql.ResultSet

SQLite 3

Using getMetaData();

DatabaseMetaData md = conn.getMetaData();
ResultSet rset = md.getColumns(null, null, "your_table_name", null);

System.out.println("your_table_name");
while (rset.next())
{
    System.out.println("\t" + rset.getString(4));
}

EDIT: This works with PostgreSQL as well

How to break a while loop from an if condition inside the while loop?

The break keyword does exactly that. Here is a contrived example:

public static void main(String[] args) {
  int i = 0;
  while (i++ < 10) {
    if (i == 5) break;
  }
  System.out.println(i); //prints 5
}

If you were actually using nested loops, you would be able to use labels.

How to get the day name from a selected date?

What about if we use String.Format here

_x000D_

DateTime today = DateTime.Today;_x000D_
String.Format("{0:dd-MM}, {1:dddd}", today, today) //In dd-MM format_x000D_
String.Format("{0:MM-dd}, {1:dddd}", today, today) //In MM-dd format

_x000D_

Get my phone number in android

As Answered here

Use below code :

TelephonyManager tMgr = (TelephonyManager)mAppContext.getSystemService(Context.TELEPHONY_SERVICE);
String mPhoneNumber = tMgr.getLine1Number();

In AndroidManifest.xml, give the following permission:

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

But remember, this code does not always work, since Cell phone number is dependent on the SIM Card and the Network operator / Cell phone carrier.

Also, try checking in Phone--> Settings --> About --> Phone Identity, If you are able to view the Number there, the probability of getting the phone number from above code is higher. If you are not able to view the phone number in the settings, then you won't be able to get via this code!

Suggested Workaround:

Get the user's phone number as manual input from the user.
Send a code to the user's mobile number via SMS.
Ask user to enter the code to confirm the phone number.
Save the number in sharedpreference.

Do the above 4 steps as one time activity during the app's first launch. Later on, whenever phone number is required, use the value available in shared preference.

Getting time and date from timestamp with php

If you dont want to change the format of date and time from the timestamp, you can use the explode function in php

$timestamp = "2012-04-02 02:57:54"
$datetime = explode(" ",$timestamp);
$date = $datetime[0];
$time = $datetime[1];

How to check if an Object is a Collection Type in Java?

Since you mentioned reflection in your question;

boolean isArray = myArray.getClass().isArray();
boolean isCollection = Collection.class.isAssignableFrom(myList.getClass());
boolean isMap = Map.class.isAssignableFrom(myMap.getClass());

Calculate cosine similarity given 2 sentence strings

Well, if you are aware of word embeddings like Glove/Word2Vec/Numberbatch, your job is half done. If not let me explain how this can be tackled. Convert each sentence into word tokens, and represent each of these tokens as vectors of high dimension (using the pre-trained word embeddings, or you could train them yourself even!). So, now you just don't capture their surface similarity but rather extract the meaning of each word which comprise the sentence as a whole. After this calculate their cosine similarity and you are set.

How do I change the UUID of a virtual disk?

The following worked for me:

run VBoxManage internalcommands sethduuid "VDI/VMDK file" twice (the first time is just to conveniently generate an UUID, you could use any other UUID generation method instead)
open the .vbox file in a text editor
replace the UUID found in Machine uuid="{...}" with the UUID you got when you ran sethduuid the first time
replace the UUID found in HardDisk uuid="{...}" and in Image uuid="{}" (towards the end) with the UUID you got when you ran sethduuid the second time

How can I strip HTML tags from a string in ASP.NET?

I've looked at the Regex based solutions suggested here, and they don't fill me with any confidence except in the most trivial cases. An angle bracket in an attribute is all it would take to break, let alone mal-formmed HTML from the wild. And what about entities like &? If you want to convert HTML into plain text, you need to decode entities too.

So I propose the method below.

Using HtmlAgilityPack, this extension method efficiently strips all HTML tags from an html fragment. Also decodes HTML entities like &. Returns just the inner text items, with a new line between each text item.

public static string RemoveHtmlTags(this string html)
{
        if (String.IsNullOrEmpty(html))
            return html;

        var doc = new HtmlAgilityPack.HtmlDocument();
        doc.LoadHtml(html);

        if (doc.DocumentNode == null || doc.DocumentNode.ChildNodes == null)
        {
            return WebUtility.HtmlDecode(html);
        }

        var sb = new StringBuilder();

        var i = 0;

        foreach (var node in doc.DocumentNode.ChildNodes)
        {
            var text = node.InnerText.SafeTrim();

            if (!String.IsNullOrEmpty(text))
            {
                sb.Append(text);

                if (i < doc.DocumentNode.ChildNodes.Count - 1)
                {
                    sb.Append(Environment.NewLine);
                }
            }

            i++;
        }

        var result = sb.ToString();

        return WebUtility.HtmlDecode(result);
}

public static string SafeTrim(this string str)
{
    if (str == null)
        return null;

    return str.Trim();
}

If you are really serious, you'd want to ignore the contents of certain HTML tags too (<script>, <style>, <svg>, <head>, <object> come to mind!) because they probably don't contain readable content in the sense we are after. What you do there will depend on your circumstances and how far you want to go, but using HtmlAgilityPack it would be pretty trivial to whitelist or blacklist selected tags.

If you are rendering the content back to an HTML page, make sure you understand XSS vulnerability & how to prevent it - i.e. always encode any user-entered text that gets rendered back onto an HTML page (> becomes > etc).

Connect Device to Mac localhost Server?

Tried everything on this page, but http://<name>.local:<PORT> only worked on my iPhone after I quit and restarted Safari...

How to create a DB for MongoDB container on start up?

Given this .env file:

DB_NAME=foo
DB_USER=bar
DB_PASSWORD=baz

And this mongo-init.sh file:

mongo --eval "db.auth('$MONGO_INITDB_ROOT_USERNAME', '$MONGO_INITDB_ROOT_PASSWORD'); db = db.getSiblingDB('$DB_NAME'); db.createUser({ user: '$DB_USER', pwd: '$DB_PASSWORD', roles: [{ role: 'readWrite', db: '$DB_NAME' }] });"

This docker-compose.yml will create the admin database and admin user, authenticate as the admin user, then create the real database and add the real user:

version: '3'

services:
#  app:
#    build: .
#    env_file: .env
#    environment:
#      DB_HOST: 'mongodb://mongodb'

  mongodb:
    image: mongo:4
    environment:
      MONGO_INITDB_ROOT_USERNAME: admin-user
      MONGO_INITDB_ROOT_PASSWORD: admin-password
      DB_NAME: $DB_NAME
      DB_USER: $DB_USER
      DB_PASSWORD: $DB_PASSWORD
    ports:
      - 27017:27017
    volumes:
      - db-data:/data/db
      - ./mongo-init.sh:/docker-entrypoint-initdb.d/mongo-init.sh

volumes:
  db-data:

OS detecting makefile

I had a case where I had to detect the difference between two versions of Fedora, to tweak the command-line options for inkscape:
- in Fedora 31, the default inkscape is 1.0beta which uses --export-file
- in Fedora < 31, the default inkscape is 0.92 which uses --export-pdf

My Makefile contains the following

# set VERSION_ID from /etc/os-release

$(eval $(shell grep VERSION_ID /etc/os-release))

# select the inkscape export syntax

ifeq ($(VERSION_ID),31)
EXPORT = export-file
else
EXPORT = export-pdf
endif

# rule to convert inkscape SVG (drawing) to PDF

%.pdf : %.svg
    inkscape --export-area-drawing $< --$(EXPORT)=$@

This works because /etc/os-release contains a line

VERSION_ID=<value>

so the shell command in the Makefile returns the string VERSION_ID=<value>, then the eval command acts on this to set the Makefile variable VERSION_ID. This can obviously be tweaked for other OS's depending how the metadata is stored. Note that in Fedora there is not a default environment variable that gives the OS version, otherwise I would have used that!

PG::ConnectionBad - could not connect to server: Connection refused

As described by @Magne, the error PG::ConnectionBad - could not connect to server: Connection refused can be presented following a major/minor version upgrade (e.g. 9.5 -> 9.6 or 9 -> 10) of PostgreSQL.

I got this error after having run brew upgrade postgresql after the release of PostgreSQL version 9.6. The problem is that major/minor version upgrades require additional steps to migrate old date to the new version.

How to check if this is your problem

You can check if this is the problem by checking the latest brew formula PostgreSQL version installed with homebrew...

$ brew info postgresql

/usr/local/Cellar/postgresql/9.5.4_1 (3,147 files, 35M)
Poured from bottle on 2016-10-14 at 13:33:28
/usr/local/Cellar/postgresql/9.6.1 (3,242 files, 36.4M) *
Poured from bottle on 2017-02-06 at 12:41:00

...and then comparing it to the current PG_VERSION

$ cat /usr/local/var/postgres/PG_VERSION
9.5

If the PG_VERSION is less than the latest brew formula and the difference is a major/minor version change, then this is probably your problem.

How to fix (i.e. how to upgrade the data)

Instructions below are for an upgrade from 9.5 to 9.6. Change the version numbers as appropriate for your own upgrade

Step 1. Make sure PostgreSQL is switched off:

$ launchctl unload ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
# or, with Homebrew...
$ brew services stop postgresql

Step 2. Make a new pristine database:

$ initdb /usr/local/var/postgres9.6 -E utf8

Step 3. Check what the old and new binary versions are:

$ ls /usr/local/Cellar/postgresql/
9.5.3   9.5.4   9.6.1

Note that in this example I am upgrading from 9.5.4 binary to 9.6.1 binary

Step 4. Migrate the current data to the new database using the pg_upgrade utility.

$ pg_upgrade \
  -d /usr/local/var/postgres \
  -D /usr/local/var/postgres9.6 \
  -b /usr/local/Cellar/postgresql/9.5.4/bin/ \
  -B /usr/local/Cellar/postgresql/9.6.1/bin/ \
  -v

-d flag specifies the current data directory
-D flag specifies the new data directory to be created
-b specifies the old binary
-B specifies the new binary we're upgrading to

Step 5. Move the old data directory out of the way

$ mv /usr/local/var/postgres /usr/local/var/postgres9.5

Step 6. Move newly created data directory to where PostgreSQL expects it to be

$ mv /usr/local/var/postgres9.6 /usr/local/var/postgres

Step 7. Start PostgreSQL again

$ launchctl load ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
# or, if you're running a current version of Homebrew
$ brew services start postgresql

Step 8. If you’re using the pg gem for Rails, you should recompile by uninstalling and reinstalling the gem (skip this step if you're not using the pg gem)

$ gem uninstall pg
$ gem install pg

Step 9.(optional) After you've reassured yourself that everything is working OK, you can run regain some disk space with the following command:

brew cleanup postgresql

...and if you're feeling really brave you can delete the old PostgreSQL data directory with the following command

rm -rf /usr/local/var/postgres9.5/

(This answer is based on an excellent blog post https://keita.blog/2016/01/09/homebrew-and-postgresql-9-5/ with some additions)

RabbitMQ / AMQP: single queue, multiple consumers for same message?

If you happen to be using the amqplib library as I am, they have a handy example of an implementation of the Publish/Subscribe RabbitMQ tutorial which you might find handy.

Change the spacing of tick marks on the axis of a plot?

There are at least two ways for achieving this in base graph (my examples are for the x-axis, but work the same for the y-axis):

Use par(xaxp = c(x1, x2, n)) or plot(..., xaxp = c(x1, x2, n)) to define the position (x1 & x2) of the extreme tick marks and the number of intervals between the tick marks (n). Accordingly, n+1 is the number of tick marks drawn. (This works only if you use no logarithmic scale, for the behavior with logarithmic scales see ?par.)
You can suppress the drawing of the axis altogether and add the tick marks later with axis().
To suppress the drawing of the axis use plot(... , xaxt = "n").
Then call axis() with side, at, and labels: axis(side = 1, at = v1, labels = v2). With side referring to the side of the axis (1 = x-axis, 2 = y-axis), v1 being a vector containing the position of the ticks (e.g., c(1, 3, 5) if your axis ranges from 0 to 6 and you want three marks), and v2 a vector containing the labels for the specified tick marks (must be of same length as v1, e.g., c("group a", "group b", "group c")). See ?axis and my updated answer to a post on stats.stackexchange for an example of this method.

How to change 1 char in the string?

Strings are immutable, meaning you can't change a character. Instead, you create new strings.

What you are asking can be done several ways. The most appropriate solution will vary depending on the nature of the changes you are making to the original string. Are you changing only one character? Do you need to insert/delete/append?

Here are a couple ways to create a new string from an existing string, but having a different first character:

str = 'M' + str.Remove(0, 1);

str = 'M' + str.Substring(1);

Above, the new string is assigned to the original variable, str.

I'd like to add that the answers from others demonstrating StringBuilder are also very appropriate. I wouldn't instantiate a StringBuilder to change one character, but if many changes are needed StringBuilder is a better solution than my examples which create a temporary new string in the process. StringBuilder provides a mutable object that allows many changes and/or append operations. Once you are done making changes, an immutable string is created from the StringBuilder with the .ToString() method. You can continue to make changes on the StringBuilder object and create more new strings, as needed, using .ToString().

Is there an equivalent to e.PageX position for 'touchstart' event as there is for click event?

I tried some of the other answers here, but originalEvent was also undefined. Upon inspection, found a TouchList classed property (as suggested by another poster) and managed to get to pageX/Y this way:

var x = e.changedTouches[0].pageX;

How to check if a URL exists or returns 404 with Java?

this worked for me:

URL u = new URL ( "http://www.example.com/");
HttpURLConnection huc =  ( HttpURLConnection )  u.openConnection (); 
huc.setRequestMethod ("GET");  //OR  huc.setRequestMethod ("HEAD"); 
huc.connect () ; 
int code = huc.getResponseCode() ;
System.out.println(code);

thanks for the suggestions above.

Set Font Color, Font Face and Font Size in PHPExcel

I recommend you start reading the documentation (4.6.18. Formatting cells). When applying a lot of formatting it's better to use applyFromArray() According to the documentation this method is also suppose to be faster when you're setting many style properties. There's an annex where you can find all the possible keys for this function.

This will work for you:

$phpExcel = new PHPExcel();

$styleArray = array(
    'font'  => array(
        'bold'  => true,
        'color' => array('rgb' => 'FF0000'),
        'size'  => 15,
        'name'  => 'Verdana'
    ));

$phpExcel->getActiveSheet()->getCell('A1')->setValue('Some text');
$phpExcel->getActiveSheet()->getStyle('A1')->applyFromArray($styleArray);

To apply font style to complete excel document:

 $styleArray = array(
   'font'  => array(
        'bold'  => true,
        'color' => array('rgb' => 'FF0000'),
        'size'  => 15,
        'name'  => 'Verdana'
    ));      
 $phpExcel->getDefaultStyle()
    ->applyFromArray($styleArray);

Excel formula to display ONLY month and year?

There are a number of ways to go about this. One way would be to enter the date 8/1/2013 manually in the first cell (say A1 for example's sake) and then in B1 type the following formula (and then drag it across):

=DATE(YEAR(A1),MONTH(A1)+1,1)

Since you only want to see month and year, you can format accordingly using the different custom date formats available.

The format you're looking for is YY-Mmm.

How do I get the first element from an IEnumerable<T> in .net?

Well, you didn't specify which version of .Net you're using.

Assuming you have 3.5, another way is the ElementAt method:

var e = enumerable.ElementAt(0);

How Can I Truncate A String In jQuery?

  function truncateString(str, length) {
     return str.length > length ? str.substring(0, length - 3) + '...' : str
  }

NodeJS: How to decode base64 encoded string back to binary?

As of Node.js v6.0.0 using the constructor method has been deprecated and the following method should instead be used to construct a new buffer from a base64 encoded string:

var b64string = /* whatever */;
var buf = Buffer.from(b64string, 'base64'); // Ta-da

For Node.js v5.11.1 and below

Construct a new Buffer and pass 'base64' as the second argument:

var b64string = /* whatever */;
var buf = new Buffer(b64string, 'base64'); // Ta-da

If you want to be clean, you can check whether from exists :

if (typeof Buffer.from === "function") {
    // Node 5.10+
    buf = Buffer.from(b64string, 'base64'); // Ta-da
} else {
    // older Node versions, now deprecated
    buf = new Buffer(b64string, 'base64'); // Ta-da
}

Best way to check if a character array is empty

if (!*text) {}

The above dereferences the pointer 'text' and checks to see if it's zero. alternatively:

if (*text == 0) {}

How do you append to an already existing string?

#!/bin/bash
message="some text"
message="$message add some more"

echo $message

some text add some more

Aligning label and textbox on same line (left and right)

You can do it with a table, like this:

<table width="100%">
  <tr>
    <td style="width: 50%">Left Text</td>
    <td style="width: 50%; text-align: right;">Right Text</td>
  </tr>
</table>

Or, you can do it with CSS like this:

<div style="float: left;">
    Left text
</div>
<div style="float: right;">
    Right text
</div>

Change string color with NSAttributedString?

Use something like this (Not compiler checked)

NSMutableAttributedString *string = [[NSMutableAttributedString alloc]initWithString:self.text.text];
NSRange range=[self.myLabel.text rangeOfString:texts[sliderValue]]; //myLabel is the outlet from where you will get the text, it can be same or different

NSArray *colors=@[[UIColor redColor],
                  [UIColor redColor],
                  [UIColor yellowColor],
                  [UIColor greenColor]
                 ];

[string addAttribute:NSForegroundColorAttributeName 
               value:colors[sliderValue] 
               range:range];           

[self.scanLabel setAttributedText:texts[sliderValue]];

HTTP GET Request in Node.js Express

Check out httpreq: it's a node library I created because I was frustrated there was no simple http GET or POST module out there ;-)

Inheritance with base class constructor with parameters

I could be wrong, but I believe since you are inheriting from foo, you have to call a base constructor. Since you explicitly defined the foo constructor to require (int, int) now you need to pass that up the chain.

public bar(int a, int b) : base(a, b)
{
     c = a * b;
}

This will initialize foo's variables first and then you can use them in bar. Also, to avoid confusion I would recommend not naming parameters the exact same as the instance variables. Try p_a or something instead, so you won't accidentally be handling the wrong variable.

jQuery: Test if checkbox is NOT checked

if ( $("#checkSurfaceEnvironment-1").is(":checked") && $("#checkSurfaceEnvironment-2").not(":checked") )

how to create a list of lists

Use append method, eg:

lst = []
line = np.genfromtxt('temp.txt', usecols=3, dtype=[('floatname','float')], skip_header=1)
lst.append(line)

How do I get the current mouse screen coordinates in WPF?

Do you want coordinates relative to the screen or the application?

If it's within the application just use:

Mouse.GetPosition(Application.Current.MainWindow);

If not, I believe you can add a reference to System.Windows.Forms and use:

System.Windows.Forms.Control.MousePosition;

Finding the position of bottom of a div with jquery

EDIT: this solution is now in the original answer too.

The accepted answer is not quite correct. You should not be using the position() function since it is relative to the parent. If you are doing global positioning(in most cases?) you should only add the offset top with the outerheight like so:

var actualBottom = $(selector).offset().top + $(selector).outerHeight(true);

The docs http://api.jquery.com/offset/

regex to match a single character that is anything but a space

\s matches any white-space character
\S matches any non-white-space character
You can match a space character with just the space character;
[^ ] matches anything but a space character.

Pick whichever is most appropriate.

IIS Config Error - This configuration section cannot be used at this path

When I tried these steps I kept getting error:

Search for "Turn windows features on or off"
Check "Internet Information Services"
Check "World Wide Web Services"
Check "Application Development Features"
Enable all items under this

Then i looked at event viewer and saw this error:Unable to install counter strings because the SYSTEM\CurrentControlSet\Services\ASP.NET_64\Performance key could not be opened or accessed. The first DWORD in the Data section contains the Win32 error code.

To fix the issue i manually created following entry in registry:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\ASP.NET_64\Performance

and followed these steps:

Search for "Turn windows features on or off"
Check "Internet Information Services"
Check "World Wide Web Services"
Check "Application Development Features"
Enable all items under this

New xampp security concept: Access Forbidden Error 403 - Windows 7 - phpMyAdmin

Try to reinstall new version of XAMPP. Find "<Directory "C:/xampp/php">" and then change to something like this

<Directory "C:/xampp/php">
    AllowOverride AuthConfig Limit
    Order allow,deny
    Allow from all
    Require all granted
</Directory>

For a boolean field, what is the naming convention for its getter/setter?

Maybe it is time to start revising this answer? Personally I would vote for setActive() and unsetActive() (alternatives can be setUnActive(), notActive(), disable(), etc. depending on context) since "setActive" implies you activate it at all times, which you don't. It's kind of counter intuitive to say "setActive" but actually remove the active state.

Another problem is, you can can not listen to specifically a SetActive event in a CQRS way, you would need to listen to a 'setActiveEvent' and determine inside that listener wether is was actually set active or not. Or of course determine which event to call when calling setActive() but that then goes against the Separation of Concerns principle.

A good read on this is the FlagArgument article by Martin Fowler: http://martinfowler.com/bliki/FlagArgument.html

However, I come from a PHP background and see this trend being adopted more and more. Not sure how much this lives with Java development.

How do I set an absolute include path in PHP?

Not directly answering your question but something to remember:

When using includes with allow_url_include on in your ini beware that, when accessing sessions from included files, if from a script you include one file using an absolute file reference and then include a second file from on your local server using a url file reference that they have different variable scope and the same session will not be seen from both included files. The original session won't be seen from the url included file.

from: http://us2.php.net/manual/en/function.include.php#84052

Difference between Fact table and Dimension table?

Dimension table Dimension table is a table which contain attributes of measurements stored in fact tables. This table consists of hierarchies, categories and logic that can be used to traverse in nodes.

Fact table contains the measurement of business processes, and it contains foreign keys for the dimension tables.

Example – If the business process is manufacturing of bricks

Average number of bricks produced by one person/machine – measure of the business process

How do I add FTP support to Eclipse?

SFTP Plug-in: http://www.jcraft.com/eclipse-sftp/ :)

Bootstrap 3 Glyphicons CDN

An alternative would be to use Font-Awesome for icons:

Including Font-Awesome

Open Font-Awesome on CDNJS and copy the CSS url of the latest version:

<link rel="stylesheet" href="<url>">

Or in CSS

@import url("<url>");

For example (note, the version will change):

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.css">

Usage:

<i class="fa fa-bed"></i>

It contains a lot of icons!

C# event with custom arguments

public enum MyEvents
{
    Event1
}

public class CustomEventArgs : EventArgs
{
    public MyEvents MyEvents { get; set; }
}


private EventHandler<CustomEventArgs> onTrigger;

public event EventHandler<CustomEventArgs> Trigger
{
    add
    {
        onTrigger += value;
    }
    remove
    {
        onTrigger -= value;
    }
}

protected void OnTrigger(CustomEventArgs e)
{
    if (onTrigger != null)
    {
        onTrigger(this, e);
    }
}

What's the difference between %s and %d in Python string formatting?

speaking of which ...
python3.6 comes with f-strings which makes things much easier in formatting!
now if your python version is greater than 3.6 you can format your strings with these available methods:

name = "python"

print ("i code with %s" %name)          # with help of older method
print ("i code with {0}".format(name))  # with help of format
print (f"i code with {name}")           # with help of f-strings

How to make a smaller RatingBar?

<RatingBar
    android:id="@+id/ratingBar1"
    android:numStars="5"
    android:stepSize=".5"
    android:rating="3.5"
    style="@android:style/Widget.DeviceDefault.RatingBar.Small"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

CodeIgniter - return only one row?

To add on to what Alisson said you could check to see if a row is returned.

// Query stuff ...
$query = $this->db->get();

if ($query->num_rows() > 0)
{
    $row = $query->row(); 
    return $row->campaign_id;
}

return null; // or whatever value you want to return for no rows found

Why is "1000000000000000 in range(1000000000000001)" so fast in Python 3?

The other answers explained it well already, but I'd like to offer another experiment illustrating the nature of range objects:

>>> r = range(5)
>>> for i in r:
        print(i, 2 in r, list(r))

0 True [0, 1, 2, 3, 4]
1 True [0, 1, 2, 3, 4]
2 True [0, 1, 2, 3, 4]
3 True [0, 1, 2, 3, 4]
4 True [0, 1, 2, 3, 4]

As you can see, a range object is an object that remembers its range and can be used many times (even while iterating over it), not just a one-time generator.

How to convert a set to a list in python?

Instead of:

first_list = [1,2,3,4]
my_set=set(first_list)
my_list = list(my_set)

Why not shortcut the process:

my_list = list(set([1,2,3,4])

This will remove the dupes from you list and return a list back to you.

Commenting out a set of lines in a shell script

This Perl one-liner comments out lines 1 to 3 of the file orig.sh inclusive (where the first line is numbered 0), and writes the commented version to cmt.sh.

perl -n -e '$s=1;$e=3; $_="#$_" if $i>=$s&&$i<=$e;print;$i++' orig.sh > cmt.sh

Obviously you can change the boundary numbers as required.

If you want to edit the file in place, it's even shorter:

perl -in -e '$s=1;$e=3; $_="#$_" if $i>=$s&&$i<=$e;print;$i++' orig.sh

Demo

$ cat orig.sh 
a
b
c
d
e
f

$ perl -n -e '$s=1;$e=3; $_="#$_" if $i>=$s&&$i<=$e;print;$i++' orig.sh > cmt.sh

$ cat cmt.sh 
a
#b
#c
#d
e
f

Variable used in lambda expression should be final or effectively final

if it is not necessary to modify the variable than a general workaround for this kind of problem would be to extract the part of code which use lambda and use final keyword on method-parameter.

Trim characters in Java

Here's how I would do it.

I think it's about as efficient as it reasonably can be. It optimizes the single character case and avoids creating multiple substrings for each subsequence removed.

Note that the corner case of passing an empty string to trim is handled (some of the other answers would go into an infinite loop).

/** Trim all occurrences of the string <code>rmvval</code> from the left and right of <code>src</code>.  Note that <code>rmvval</code> constitutes an entire string which must match using <code>String.startsWith</code> and <code>String.endsWith</code>. */
static public String trim(String src, String rmvval) {
    return trim(src,rmvval,rmvval,true);
    }

/** Trim all occurrences of the string <code>lftval</code> from the left and <code>rgtval</code> from the right of <code>src</code>.  Note that the values to remove constitute strings which must match using <code>String.startsWith</code> and <code>String.endsWith</code>. */
static public String trim(String src, String lftval, String rgtval, boolean igncas) {
    int                                 str=0,end=src.length();

    if(lftval.length()==1) {                                                    // optimize for common use - trimming a single character from left
        char chr=lftval.charAt(0);
        while(str<end && src.charAt(str)==chr) { str++; }
        }
    else if(lftval.length()>1) {                                                // handle repeated removal of a specific character sequence from left
        int vallen=lftval.length(),newstr;
        while((newstr=(str+vallen))<=end && src.regionMatches(igncas,str,lftval,0,vallen)) { str=newstr; }
        }

    if(rgtval.length()==1) {                                                    // optimize for common use - trimming a single character from right
        char chr=rgtval.charAt(0);
        while(str<end && src.charAt(end-1)==chr) { end--; }
        }
    else if(rgtval.length()>1) {                                                // handle repeated removal of a specific character sequence from right
        int vallen=rgtval.length(),newend;
        while(str<=(newend=(end-vallen)) && src.regionMatches(igncas,newend,rgtval,0,vallen)) { end=newend; }
        }

    if(str!=0 || end!=src.length()) {
        if(str<end) { src=src.substring(str,end); }                            // str is inclusive, end is exclusive
        else        { src="";                     }
        }

    return src;
    }

Check if a PHP cookie exists and if not set its value

Cookies are only sent at the time of the request, and therefore cannot be retrieved as soon as it is assigned (only available after reloading).

Once the cookies have been set, they can be accessed on the next page load with the $_COOKIE or $HTTP_COOKIE_VARS arrays.

If output exists prior to calling this function, setcookie() will fail and return FALSE. If setcookie() successfully runs, it will return TRUE. This does not indicate whether the user accepted the cookie.

Cookies will not become visible until the next loading of a page that the cookie should be visible for. To test if a cookie was successfully set, check for the cookie on a next loading page before the cookie expires. Expire time is set via the expire parameter. A nice way to debug the existence of cookies is by simply calling print_r($_COOKIE);.

Source

xxxxxx.exe is not a valid Win32 application

I had the same issue on Windows XP when running an application built with a static version of Qt 5.7.0 (MSVC 2013).

Adding the following line to the project's .pro file solved it:

QMAKE_LFLAGS_WINDOWS = /SUBSYSTEM:WINDOWS,5.01

Why does the C preprocessor interpret the word "linux" as the constant "1"?

Use this command

gcc -dM -E - < /dev/null

to get this

    #define _LP64 1
#define _STDC_PREDEF_H 1
#define __ATOMIC_ACQUIRE 2
#define __ATOMIC_ACQ_REL 4
#define __ATOMIC_CONSUME 1
#define __ATOMIC_HLE_ACQUIRE 65536
#define __ATOMIC_HLE_RELEASE 131072
#define __ATOMIC_RELAXED 0
#define __ATOMIC_RELEASE 3
#define __ATOMIC_SEQ_CST 5
#define __BIGGEST_ALIGNMENT__ 16
#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
#define __CHAR16_TYPE__ short unsigned int
#define __CHAR32_TYPE__ unsigned int
#define __CHAR_BIT__ 8
#define __DBL_DECIMAL_DIG__ 17
#define __DBL_DENORM_MIN__ ((double)4.94065645841246544177e-324L)
#define __DBL_DIG__ 15
#define __DBL_EPSILON__ ((double)2.22044604925031308085e-16L)
#define __DBL_HAS_DENORM__ 1
#define __DBL_HAS_INFINITY__ 1
#define __DBL_HAS_QUIET_NAN__ 1
#define __DBL_MANT_DIG__ 53
#define __DBL_MAX_10_EXP__ 308
#define __DBL_MAX_EXP__ 1024
#define __DBL_MAX__ ((double)1.79769313486231570815e+308L)
#define __DBL_MIN_10_EXP__ (-307)
#define __DBL_MIN_EXP__ (-1021)
#define __DBL_MIN__ ((double)2.22507385850720138309e-308L)
#define __DEC128_EPSILON__ 1E-33DL
#define __DEC128_MANT_DIG__ 34
#define __DEC128_MAX_EXP__ 6145
#define __DEC128_MAX__ 9.999999999999999999999999999999999E6144DL
#define __DEC128_MIN_EXP__ (-6142)
#define __DEC128_MIN__ 1E-6143DL
#define __DEC128_SUBNORMAL_MIN__ 0.000000000000000000000000000000001E-6143DL
#define __DEC32_EPSILON__ 1E-6DF
#define __DEC32_MANT_DIG__ 7
#define __DEC32_MAX_EXP__ 97
#define __DEC32_MAX__ 9.999999E96DF
#define __DEC32_MIN_EXP__ (-94)
#define __DEC32_MIN__ 1E-95DF
#define __DEC32_SUBNORMAL_MIN__ 0.000001E-95DF
#define __DEC64_EPSILON__ 1E-15DD
#define __DEC64_MANT_DIG__ 16
#define __DEC64_MAX_EXP__ 385
#define __DEC64_MAX__ 9.999999999999999E384DD
#define __DEC64_MIN_EXP__ (-382)
#define __DEC64_MIN__ 1E-383DD
#define __DEC64_SUBNORMAL_MIN__ 0.000000000000001E-383DD
#define __DECIMAL_BID_FORMAT__ 1
#define __DECIMAL_DIG__ 21
#define __DEC_EVAL_METHOD__ 2
#define __ELF__ 1
#define __FINITE_MATH_ONLY__ 0
#define __FLOAT_WORD_ORDER__ __ORDER_LITTLE_ENDIAN__
#define __FLT_DECIMAL_DIG__ 9
#define __FLT_DENORM_MIN__ 1.40129846432481707092e-45F
#define __FLT_DIG__ 6
#define __FLT_EPSILON__ 1.19209289550781250000e-7F
#define __FLT_EVAL_METHOD__ 0
#define __FLT_HAS_DENORM__ 1
#define __FLT_HAS_INFINITY__ 1
#define __FLT_HAS_QUIET_NAN__ 1
#define __FLT_MANT_DIG__ 24
#define __FLT_MAX_10_EXP__ 38
#define __FLT_MAX_EXP__ 128
#define __FLT_MAX__ 3.40282346638528859812e+38F
#define __FLT_MIN_10_EXP__ (-37)
#define __FLT_MIN_EXP__ (-125)
#define __FLT_MIN__ 1.17549435082228750797e-38F
#define __FLT_RADIX__ 2
#define __FXSR__ 1
#define __GCC_ASM_FLAG_OUTPUTS__ 1
#define __GCC_ATOMIC_BOOL_LOCK_FREE 2
#define __GCC_ATOMIC_CHAR16_T_LOCK_FREE 2
#define __GCC_ATOMIC_CHAR32_T_LOCK_FREE 2
#define __GCC_ATOMIC_CHAR_LOCK_FREE 2
#define __GCC_ATOMIC_INT_LOCK_FREE 2
#define __GCC_ATOMIC_LLONG_LOCK_FREE 2
#define __GCC_ATOMIC_LONG_LOCK_FREE 2
#define __GCC_ATOMIC_POINTER_LOCK_FREE 2
#define __GCC_ATOMIC_SHORT_LOCK_FREE 2
#define __GCC_ATOMIC_TEST_AND_SET_TRUEVAL 1
#define __GCC_ATOMIC_WCHAR_T_LOCK_FREE 2
#define __GCC_HAVE_DWARF2_CFI_ASM 1
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_1 1
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2 1
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 1
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8 1
#define __GCC_IEC_559 2
#define __GCC_IEC_559_COMPLEX 2
#define __GNUC_MINOR__ 3
#define __GNUC_PATCHLEVEL__ 0
#define __GNUC_STDC_INLINE__ 1
#define __GNUC__ 6
#define __GXX_ABI_VERSION 1010
#define __INT16_C(c) c
#define __INT16_MAX__ 0x7fff
#define __INT16_TYPE__ short int
#define __INT32_C(c) c
#define __INT32_MAX__ 0x7fffffff
#define __INT32_TYPE__ int
#define __INT64_C(c) c ## L
#define __INT64_MAX__ 0x7fffffffffffffffL
#define __INT64_TYPE__ long int
#define __INT8_C(c) c
#define __INT8_MAX__ 0x7f
#define __INT8_TYPE__ signed char
#define __INTMAX_C(c) c ## L
#define __INTMAX_MAX__ 0x7fffffffffffffffL
#define __INTMAX_TYPE__ long int
#define __INTPTR_MAX__ 0x7fffffffffffffffL
#define __INTPTR_TYPE__ long int
#define __INT_FAST16_MAX__ 0x7fffffffffffffffL
#define __INT_FAST16_TYPE__ long int
#define __INT_FAST32_MAX__ 0x7fffffffffffffffL
#define __INT_FAST32_TYPE__ long int
#define __INT_FAST64_MAX__ 0x7fffffffffffffffL
#define __INT_FAST64_TYPE__ long int
#define __INT_FAST8_MAX__ 0x7f
#define __INT_FAST8_TYPE__ signed char
#define __INT_LEAST16_MAX__ 0x7fff
#define __INT_LEAST16_TYPE__ short int
#define __INT_LEAST32_MAX__ 0x7fffffff
#define __INT_LEAST32_TYPE__ int
#define __INT_LEAST64_MAX__ 0x7fffffffffffffffL
#define __INT_LEAST64_TYPE__ long int
#define __INT_LEAST8_MAX__ 0x7f
#define __INT_LEAST8_TYPE__ signed char
#define __INT_MAX__ 0x7fffffff
#define __LDBL_DENORM_MIN__ 3.64519953188247460253e-4951L
#define __LDBL_DIG__ 18
#define __LDBL_EPSILON__ 1.08420217248550443401e-19L
#define __LDBL_HAS_DENORM__ 1
#define __LDBL_HAS_INFINITY__ 1
#define __LDBL_HAS_QUIET_NAN__ 1
#define __LDBL_MANT_DIG__ 64
#define __LDBL_MAX_10_EXP__ 4932
#define __LDBL_MAX_EXP__ 16384
#define __LDBL_MAX__ 1.18973149535723176502e+4932L
#define __LDBL_MIN_10_EXP__ (-4931)
#define __LDBL_MIN_EXP__ (-16381)
#define __LDBL_MIN__ 3.36210314311209350626e-4932L
#define __LONG_LONG_MAX__ 0x7fffffffffffffffLL
#define __LONG_MAX__ 0x7fffffffffffffffL
#define __LP64__ 1
#define __MMX__ 1
#define __NO_INLINE__ 1
#define __ORDER_BIG_ENDIAN__ 4321
#define __ORDER_LITTLE_ENDIAN__ 1234
#define __ORDER_PDP_ENDIAN__ 3412
#define __PIC__ 2
#define __PIE__ 2
#define __PRAGMA_REDEFINE_EXTNAME 1
#define __PTRDIFF_MAX__ 0x7fffffffffffffffL
#define __PTRDIFF_TYPE__ long int
#define __REGISTER_PREFIX__ 
#define __SCHAR_MAX__ 0x7f
#define __SEG_FS 1
#define __SEG_GS 1
#define __SHRT_MAX__ 0x7fff
#define __SIG_ATOMIC_MAX__ 0x7fffffff
#define __SIG_ATOMIC_MIN__ (-__SIG_ATOMIC_MAX__ - 1)
#define __SIG_ATOMIC_TYPE__ int
#define __SIZEOF_DOUBLE__ 8
#define __SIZEOF_FLOAT128__ 16
#define __SIZEOF_FLOAT80__ 16
#define __SIZEOF_FLOAT__ 4
#define __SIZEOF_INT128__ 16
#define __SIZEOF_INT__ 4
#define __SIZEOF_LONG_DOUBLE__ 16
#define __SIZEOF_LONG_LONG__ 8
#define __SIZEOF_LONG__ 8
#define __SIZEOF_POINTER__ 8
#define __SIZEOF_PTRDIFF_T__ 8
#define __SIZEOF_SHORT__ 2
#define __SIZEOF_SIZE_T__ 8
#define __SIZEOF_WCHAR_T__ 4
#define __SIZEOF_WINT_T__ 4
#define __SIZE_MAX__ 0xffffffffffffffffUL
#define __SIZE_TYPE__ long unsigned int
#define __SSE2_MATH__ 1
#define __SSE2__ 1
#define __SSE_MATH__ 1
#define __SSE__ 1
#define __SSP_STRONG__ 3
#define __STDC_HOSTED__ 1
#define __STDC_IEC_559_COMPLEX__ 1
#define __STDC_IEC_559__ 1
#define __STDC_ISO_10646__ 201605L
#define __STDC_NO_THREADS__ 1
#define __STDC_UTF_16__ 1
#define __STDC_UTF_32__ 1
#define __STDC_VERSION__ 201112L
#define __STDC__ 1
#define __UINT16_C(c) c
#define __UINT16_MAX__ 0xffff
#define __UINT16_TYPE__ short unsigned int
#define __UINT32_C(c) c ## U
#define __UINT32_MAX__ 0xffffffffU
#define __UINT32_TYPE__ unsigned int
#define __UINT64_C(c) c ## UL
#define __UINT64_MAX__ 0xffffffffffffffffUL
#define __UINT64_TYPE__ long unsigned int
#define __UINT8_C(c) c
#define __UINT8_MAX__ 0xff
#define __UINT8_TYPE__ unsigned char
#define __UINTMAX_C(c) c ## UL
#define __UINTMAX_MAX__ 0xffffffffffffffffUL
#define __UINTMAX_TYPE__ long unsigned int
#define __UINTPTR_MAX__ 0xffffffffffffffffUL
#define __UINTPTR_TYPE__ long unsigned int
#define __UINT_FAST16_MAX__ 0xffffffffffffffffUL
#define __UINT_FAST16_TYPE__ long unsigned int
#define __UINT_FAST32_MAX__ 0xffffffffffffffffUL
#define __UINT_FAST32_TYPE__ long unsigned int
#define __UINT_FAST64_MAX__ 0xffffffffffffffffUL
#define __UINT_FAST64_TYPE__ long unsigned int
#define __UINT_FAST8_MAX__ 0xff
#define __UINT_FAST8_TYPE__ unsigned char
#define __UINT_LEAST16_MAX__ 0xffff
#define __UINT_LEAST16_TYPE__ short unsigned int
#define __UINT_LEAST32_MAX__ 0xffffffffU
#define __UINT_LEAST32_TYPE__ unsigned int
#define __UINT_LEAST64_MAX__ 0xffffffffffffffffUL
#define __UINT_LEAST64_TYPE__ long unsigned int
#define __UINT_LEAST8_MAX__ 0xff
#define __UINT_LEAST8_TYPE__ unsigned char
#define __USER_LABEL_PREFIX__ 
#define __VERSION__ "6.3.0 20170406"
#define __WCHAR_MAX__ 0x7fffffff
#define __WCHAR_MIN__ (-__WCHAR_MAX__ - 1)
#define __WCHAR_TYPE__ int
#define __WINT_MAX__ 0xffffffffU
#define __WINT_MIN__ 0U
#define __WINT_TYPE__ unsigned int
#define __amd64 1
#define __amd64__ 1
#define __code_model_small__ 1
#define __gnu_linux__ 1
#define __has_include(STR) __has_include__(STR)
#define __has_include_next(STR) __has_include_next__(STR)
#define __k8 1
#define __k8__ 1
#define __linux 1
#define __linux__ 1
#define __pic__ 2
#define __pie__ 2
#define __unix 1
#define __unix__ 1
#define __x86_64 1
#define __x86_64__ 1
#define linux 1
#define unix 1

Excel Macro : How can I get the timestamp in "yyyy-MM-dd hh:mm:ss" format?

Use the Format function.

Format(Date, "yyyy-mm-dd hh:MM:ss")

Spring AMQP + RabbitMQ 3.3.5 ACCESS_REFUSED - Login was refused using authentication mechanism PLAIN

user 'guest' can only connect via localhost

That's true since RabbitMQ 3.3.x. Hence you should upgrade to the same version the client library, or just upgrade Spring AMQP to the latest version (if you use dependency managent system).

Previous version of client used 127.0.0.1 as default value for the host option of ConnectionFactory.

How can VBA connect to MySQL database in Excel?

Enable Microsoft ActiveX Data Objects 2.8 Library

Dim oConn As ADODB.Connection 
Private Sub ConnectDB()     
Set oConn = New ADODB.Connection    
oConn.Open "DRIVER={MySQL ODBC 5.1 Driver};" & _        
"SERVER=localhost;" & _         
"DATABASE=yourdatabase;" & _        
"USER=yourdbusername;" & _      
"PASSWORD=yourdbpassword;" & _      
"Option=3" 
End Sub

There rest is here: http://www.heritage-tech.net/908/inserting-data-into-mysql-from-excel-using-vba/

Split List into Sublists with LINQ

public static List<List<T>> GetSplitItemsList<T>(List<T> originalItemsList, short number)
    {
        var listGroup = new List<List<T>>();
        int j = number;
        for (int i = 0; i < originalItemsList.Count; i += number)
        {
            var cList = originalItemsList.Take(j).Skip(i).ToList();
            j += number;
            listGroup.Add(cList);
        }
        return listGroup;
    }

How to select a radio button by default?

Use the checked attribute.

<input type="radio" name="imgsel"  value="" checked />

<input type="radio" name="imgsel"  value="" checked="checked" />

How to set JAVA_HOME environment variable on Mac OS X 10.9?

Literally all you have to do is:

echo export "JAVA_HOME=\$(/usr/libexec/java_home)" >> ~/.bash_profile

and restart your shell.

If you have multiple JDK versions installed and you want it to be a specific one, you can use the -v flag to java_home like so:

echo export "JAVA_HOME=\$(/usr/libexec/java_home -v 1.7)" >> ~/.bash_profile

VBA (Excel) Initialize Entire Array without Looping

This is easy, at least if you want a 1-based, 1D or 2D variant array:

Sub StuffVArr()
    Dim v() As Variant
    Dim q() As Variant
    v = Evaluate("=IF(ISERROR(A1:K1), 13, 13)")
    q = Evaluate("=IF(ISERROR(A1:G48), 13, 13)")
End Sub

Byte arrays also aren't too bad:

Private Declare Sub FillMemory Lib "kernel32" Alias "RtlFillMemory" _
        (dest As Any, ByVal size As Long, ByVal fill As Byte)

Sub StuffBArr()
    Dim i(0 To 39) As Byte
    Dim j(1 To 2, 5 To 29, 2 To 6) As Byte
    FillMemory i(0), 40, 13
    FillMemory j(1, 5, 2), 2 * 25 * 5, 13
End Sub

You can use the same method to fill arrays of other numeric data types, but you're limited to only values which can be represented with a single repeating byte:

Sub StuffNArrs()
    Dim i(0 To 4) As Long
    Dim j(0 To 4) As Integer
    Dim u(0 To 4) As Currency
    Dim f(0 To 4) As Single
    Dim g(0 To 4) As Double

    FillMemory i(0), 5 * LenB(i(0)), &HFF 'gives -1
    FillMemory i(0), 5 * LenB(i(0)), &H80 'gives -2139062144
    FillMemory i(0), 5 * LenB(i(0)), &H7F 'gives 2139062143

    FillMemory j(0), 5 * LenB(j(0)), &HFF 'gives -1

    FillMemory u(0), 5 * LenB(u(0)), &HFF 'gives -0.0001

    FillMemory f(0), 5 * LenB(f(0)), &HFF 'gives -1.#QNAN
    FillMemory f(0), 5 * LenB(f(0)), &H80 'gives -1.18e-38
    FillMemory f(0), 5 * LenB(f(0)), &H7F 'gives 3.40e+38

    FillMemory g(0), 5 * LenB(g(0)), &HFF 'gives -1.#QNAN
End Sub

If you want to avoid a loop in other situations, it gets even hairier. Not really worth it unless your array is 50K entries or larger. Just set each value in a loop and you'll be fast enough, as I talked about in an earlier answer.

How to catch and print the full exception traceback without halting/exiting the program?

traceback.format_exception

If you only have the exception object, you can get the traceback as a string from any point of the code in Python 3 with:

import traceback

''.join(traceback.format_exception(None, exc_obj, exc_obj.__traceback__))

Full example:

#!/usr/bin/env python3

import traceback

def f():
    g()

def g():
    raise Exception('asdf')

try:
    g()
except Exception as e:
    exc = e

tb_str = ''.join(traceback.format_exception(None, exc_obj, exc_obj.__traceback__))
print(tb_str)

Output:

Traceback (most recent call last):
  File "./main.py", line 12, in <module>
    g()
  File "./main.py", line 9, in g
    raise Exception('asdf')
Exception: asdf

Documentation: https://docs.python.org/3.7/library/traceback.html#traceback.format_exception

Tested in Python 3.7.3.

How can I debug my JavaScript code?

I used to use Firebug, until Internet Explorer 8 came out. I'm not a huge fan of Internet Explorer, but after spending some time with the built-in developer tools, which includes a really nice debugger, it seems pointless to use anything else. I have to tip my hat to Microsoft they did a fantastic job on this tool.

Creating a static class with no instances

You could use a classmethod or staticmethod

class Paul(object):
    elems = []

    @classmethod
    def addelem(cls, e):
        cls.elems.append(e)

    @staticmethod
    def addelem2(e):
        Paul.elems.append(e)

Paul.addelem(1)
Paul.addelem2(2)

print(Paul.elems)

classmethod has advantage that it would work with sub classes, if you really wanted that functionality.

module is certainly best though.

How To Check If A Key in **kwargs Exists?

One way is to add it by yourself! How? By merging kwargs with a bunch of defaults. This won't be appropriate on all occasions, for example, if the keys are not known to you in advance. However, if they are, here is a simple example:

import sys

def myfunc(**kwargs):
    args = {'country':'England','town':'London',
            'currency':'Pound', 'language':'English'}

    diff = set(kwargs.keys()) - set(args.keys())
    if diff:
        print("Invalid args:",tuple(diff),file=sys.stderr)
        return

    args.update(kwargs)            
    print(args)

The defaults are set in the dictionary args, which includes all the keys we are expecting. We first check to see if there are any unexpected keys in kwargs. Then we update args with kwargs which will overwrite any new values that the user has set. We don't need to test if a key exists, we now use args as our argument dictionary and have no further need of kwargs.

How do I resize a Google Map with JavaScript after it has loaded?

If you're using Google Maps v2, call checkResize() on your map after resizing the container. link

UPDATE

Google Maps JavaScript API v2 was deprecated in 2011. It is not available anymore.

Determine path of the executing script

I have wrapped up and extended the answers to this question into a new function thisfile() in rprojroot. Also works for knitting with knitr.

calling javascript function on OnClientClick event of a Submit button

The above solutions must work. However you can try this one:

OnClientClick="return SomeMethod();return false;"

and remove return statement from the method.

JPA - Returning an auto generated id after persist()

em.persist(abc);
em.refresh(abc);
return abc;

/usr/lib/x86_64-linux-gnu/libstdc++.so.6: version CXXABI_1.3.8' not found

I ran into this issue on my Ubuntu-64 system when attempting to import fst within python as such:

    Python 3.4.3 |Continuum Analytics, Inc.| (default, Jun  4 2015, 15:29:08)
[GCC 4.4.7 20120313 (Red Hat 4.4.7-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import fst
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/ogi/miniconda3/lib/python3.4/site-packages/pyfst-0.2.3.dev0-py3.4-linux-x86_64.egg/fst/__init__.py", line 1, in <module>
    from fst._fst import EPSILON, EPSILON_ID, SymbolTable,\
ImportError: /home/ogi/miniconda3/lib/libstdc++.so.6: version `CXXABI_1.3.8' not found (required by /usr/local/lib/libfst.so.1)

I then ran:

ogi@ubuntu:~/miniconda3/lib$ find ~/ -name "libstdc++.so.6"
/home/ogi/miniconda3/lib/libstdc++.so.6
/home/ogi/miniconda3/pkgs/libgcc-5-5.2.0-2/lib/libstdc++.so.6
/home/ogi/miniconda3/pkgs/libgcc-4.8.5-1/lib/libstdc++.so.6
find: `/home/ogi/.local/share/jupyter/runtime': Permission denied
ogi@ubuntu:~/miniconda3/lib$

mv /home/ogi/miniconda3/lib/libstdc++.so.6 /home/ogi/miniconda3/libstdc++.so.6.old
cp /home/ogi/miniconda3/libgcc-5-5.2.0-2/lib/libstdc++.so.6 /home/ogi/miniconda3/lib/

At which point I was then able to load the library

ogi@ubuntu:~/miniconda3/lib$ python
Python 3.4.3 |Continuum Analytics, Inc.| (default, Jun  4 2015, 15:29:08)
[GCC 4.4.7 20120313 (Red Hat 4.4.7-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import fst
>>> exit()

How to change language of app when user selects language?

Udhay's sample code works well. Except the question of Sofiane Hassaini and Chirag SolankI, for the re-entrance, it doesn't work. I try to call Udhay's code without restart the activity in onCreate() , before super.onCreate(savedInstanceState);. Then it is OK! Only a little problem, the menu strings still not changed to the set Locale.

    public void setLocale(String lang) { //call this in onCreate()
      Locale myLocale = new Locale(lang); 
      Resources res = getResources(); 
      DisplayMetrics dm = res.getDisplayMetrics(); 
      Configuration conf = res.getConfiguration(); 
      conf.locale = myLocale; 
      res.updateConfiguration(conf, dm); 
      //Intent refresh = new Intent(this, AndroidLocalize.class); 
      //startActivity(refresh); 
      //finish();
    }

Send HTML in email via PHP

You need to code your html using absolute path for images. By Absolute path means you have to upload the images in a server and in the src attribute of images you have to give the direct path like this <img src="http://yourdomain.com/images/example.jpg">.

Below is the PHP code for your refference :- Its taken from http://www.php.net/manual/en/function.mail.php

<?php
// multiple recipients
$to  = '[email protected]' . ', '; // note the comma
$to .= '[email protected]';

// subject
$subject = 'Birthday Reminders for August';

// message
$message = '
  <p>Here are the birthdays upcoming in August!</p>
';

// To send HTML mail, the Content-type header must be set
$headers  = 'MIME-Version: 1.0' . "\r\n";
$headers .= 'Content-type: text/html; charset=UTF-8' . "\r\n";

// Additional headers
$headers .= 'To: Mary <[email protected]>, Kelly <[email protected]>' . "\r\n";
$headers .= 'From: Birthday Reminder <[email protected]>' . "\r\n";


// Mail it
mail($to, $subject, $message, $headers);
?>

Escape text for HTML

If you're using .NET 4 or above and you don't want to reference System.Web, you can use WebUtility.HtmlEncode from System

var encoded = WebUtility.HtmlEncode(unencoded);

This has the same effect as HttpUtility.HtmlEncode and should be preferred over System.Security.SecurityElement.Escape.

How can I make a ComboBox non-editable in .NET?

for winforms .NET change DropDownStyle to DropDownList from Combobox property

Delete specified file from document directory

Instead of having the error set to NULL, have it set to

NSError *error;
[fileManager removeItemAtPath:filePath error:&error];
if (error){
NSLog(@"%@", error);
}

this will tell you if it's actually deleting the file

Convert an image to grayscale in HTML/CSS

Based on robertc's answer:

To get proper conversion from colored image to grayscale image instead of using matrix like this:

0.3333 0.3333 0.3333 0 0
0.3333 0.3333 0.3333 0 0
0.3333 0.3333 0.3333 0 0
0      0      0      1 0

You should use conversion matrix like this:

0.299 0.299 0.299 0
0.587 0.587 0.587 0
0.112 0.112 0.112 0
0     0     0     1

This should work fine for all the types of images based on RGBA (red-green-blue-alpha) model.

For more information why you should use matrix I posted more likely that the robertc's one check following links:

C++ - struct vs. class

POD classes are Plain-Old data classes that have only data members and nothing else. There are a few questions on stackoverflow about the same. Find one here.

Also, you can have functions as members of structs in C++ but not in C. You need to have pointers to functions as members in structs in C.

Spring RestTemplate - how to enable full debugging/logging of requests/responses?

Just to complete the example with a full implementation of ClientHttpRequestInterceptor to trace request and response:

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpRequest;
import org.springframework.http.client.ClientHttpRequestExecution;
import org.springframework.http.client.ClientHttpRequestInterceptor;
import org.springframework.http.client.ClientHttpResponse;

public class LoggingRequestInterceptor implements ClientHttpRequestInterceptor {

    final static Logger log = LoggerFactory.getLogger(LoggingRequestInterceptor.class);

    @Override
    public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException {
        traceRequest(request, body);
        ClientHttpResponse response = execution.execute(request, body);
        traceResponse(response);
        return response;
    }

    private void traceRequest(HttpRequest request, byte[] body) throws IOException {
        log.info("===========================request begin================================================");
        log.debug("URI         : {}", request.getURI());
        log.debug("Method      : {}", request.getMethod());
        log.debug("Headers     : {}", request.getHeaders() );
        log.debug("Request body: {}", new String(body, "UTF-8"));
        log.info("==========================request end================================================");
    }

    private void traceResponse(ClientHttpResponse response) throws IOException {
        StringBuilder inputStringBuilder = new StringBuilder();
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(response.getBody(), "UTF-8"));
        String line = bufferedReader.readLine();
        while (line != null) {
            inputStringBuilder.append(line);
            inputStringBuilder.append('\n');
            line = bufferedReader.readLine();
        }
        log.info("============================response begin==========================================");
        log.debug("Status code  : {}", response.getStatusCode());
        log.debug("Status text  : {}", response.getStatusText());
        log.debug("Headers      : {}", response.getHeaders());
        log.debug("Response body: {}", inputStringBuilder.toString());
        log.info("=======================response end=================================================");
    }

}

Then instantiate RestTemplate using a BufferingClientHttpRequestFactory and the LoggingRequestInterceptor:

RestTemplate restTemplate = new RestTemplate(new BufferingClientHttpRequestFactory(new SimpleClientHttpRequestFactory()));
List<ClientHttpRequestInterceptor> interceptors = new ArrayList<>();
interceptors.add(new LoggingRequestInterceptor());
restTemplate.setInterceptors(interceptors);

The BufferingClientHttpRequestFactory is required as we want to use the response body both in the interceptor and for the initial calling code. The default implementation allows to read the response body only once.

What is the use of BindingResult interface in spring MVC?

BindingResult is used for validation..

Example:-

 public @ResponseBody String nutzer(@ModelAttribute(value="nutzer") Nutzer nutzer, BindingResult ergebnis){
        String ergebnisText;
        if(!ergebnis.hasErrors()){
            nutzerList.add(nutzer);
            ergebnisText = "Anzahl: " + nutzerList.size();
        }else{
            ergebnisText = "Error!!!!!!!!!!!";
        }
        return ergebnisText;
    }

What is the C# Using block and why should I use it?

using (B a = new B())
{
   DoSomethingWith(a);
}

is equivalent to

B a = new B();
try
{
  DoSomethingWith(a);
}
finally
{
   ((IDisposable)a).Dispose();
}

How to jump back to NERDTree from file in tab?

NERDTree opens up in another window. That split view you're seeing? They're called windows in vim parlance. All the window commands start with CTRL-W. To move from adjacent windows that are left and right of one another, you can change focus to the window to the left of your current window with CTRL-w h, and move focus to the right with CTRL-w l. Likewise, CTRL-w j and CTRL-w k will move you between horizontally split windows (i.e., one window is above the other). There's a lot more you can do with windows as described here.

You can also use the :NERDTreeToggle command to make your tree open and close. I usually bind that do t.

Error to run Android Studio

Check if your Java JDK is installed correctly

dpkg --list | grep -i jdk

If not, install JDK

sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update && sudo apt-get install oracle-java8-installer

After the installation you have to enable the jdk

update-alternatives --display java

Check if Ubuntu uses Java JDK 8

java -version

If all went right the answer should be something like this:

java version "1.8.0_91"
Java(TM) SE Runtime Environment (build 1.8.0_91-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.91-b14, mixed mode)

Check what compiler is used

javac -version

It should show something like this

javac 1.8.0_91

Finally, add JAVA_HOME to the environment variable

Edit /etc/environment and add JAVA_HOME=/usr/lib/jvm/java-8-oracle to the end of the file

sudo nano /etc/environment

Append to the end of the file

JAVA_HOME=/usr/lib/jvm/java-8-oracle

You will then have to reboot, you can do this from the terminal with:

sudo reboot

In case you want to remove the JDK

sudo apt-get remove oracle-java8-installer

Set session variable in laravel

In Laravel 5.6, you will need to set it as

  session(['variableName'=>$value]);

To retrieve it is as simple as

$variableName = session('variableName')

Complexities of binary tree traversals

Depth first traversal of a binary tree is of order O(n).

Algo -- <b>
    PreOrderTrav():-----------------T(n)<b>
    if root is null---------------O(1)<b>
      return null-----------------O(1)<b>
    else:-------------------------O(1)<b>
      print(root)-----------------O(1)<b>
      PreOrderTrav(root.left)-----T(n/2)<b>
      PreOrderTrav(root.right)----T(n/2)<b>

If the time complexity of the algo is T(n) then it can be written as T(n) = 2*T(n/2) + O(1). If we apply back substitution we will get T(n) = O(n).

CUDA incompatible with my gcc version

As already pointed out, nvcc depends on gcc 4.4. It is possible to configure nvcc to use the correct version of gcc without passing any compiler parameters by adding softlinks to the bin directory created with the nvcc install.

The default cuda binary directory (the installation default) is /usr/local/cuda/bin, adding a softlink to the correct version of gcc from this directory is sufficient:

sudo ln -s /usr/bin/gcc-4.4 /usr/local/cuda/bin/gcc

How do you add an image?

Never mind -- I'm an idiot. I just needed <xsl:value-of select="/root/Image/node()"/>

Laravel 5: Retrieve JSON array from $request

 $postbody='';
 // Check for presence of a body in the request
 if (count($request->json()->all())) {
     $postbody = $request->json()->all();
 }

This is how it's done in laravel 5.2 now.

How to sum digits of an integer in java?

Sums all the digits regardless of number's size.

private static int sumOfAll(int num) {
    int sum = 0;

    if(num == 10) return 1;

    if(num > 10) {
        sum += num % 10;
        while((num = num / 10) >= 1) {
            sum += (num > 10) ? num%10 : num;
        }
    } else {
        sum += num;
    }
    return sum;
}

iOS - UIImageView - how to handle UIImage image orientation

Swift 3.0 version of Tommy's answer

let imageToDisplay = UIImage.init(cgImage: originalImage.cgImage!, scale: originalImage.scale, orientation: UIImageOrientation.up)

Add newline to VBA or Visual Basic 6

Visual Basic has built-in constants for newlines:

vbCr = Chr$(13) = CR (carriage-return character) - used by Mac OS and Apple II family

vbLf = Chr$(10) = LF (line-feed character) - used by Linux and Mac OS X

vbCrLf = Chr$(13) & Chr$(10) = CRLF (carriage-return followed by line-feed) - used by Windows

vbNewLine = the same as vbCrLf

Add one day to date in javascript

I think what you are looking for is:

startDate.setDate(startDate.getDate() + 1);

Also, you can have a look at Moment.js

A javascript date library for parsing, validating, manipulating, and formatting dates.

Best way to get child nodes

The cross browser way to do is to use childNodes to get NodeList, then make an array of all nodes with nodeType ELEMENT_NODE.

/**
 * Return direct children elements.
 *
 * @param {HTMLElement}
 * @return {Array}
 */
function elementChildren (element) {
    var childNodes = element.childNodes,
        children = [],
        i = childNodes.length;

    while (i--) {
        if (childNodes[i].nodeType == 1) {
            children.unshift(childNodes[i]);
        }
    }

    return children;
}

http://jsfiddle.net/s4kxnahu/

This is especially easy if you are using a utility library such as lodash:

/**
 * Return direct children elements.
 *
 * @param {HTMLElement}
 * @return {Array}
 */
function elementChildren (element) {
    return _.where(element.childNodes, {nodeType: 1});
}

Future:

You can use querySelectorAll in combination with :scope pseudo-class (matches the element that is the reference point of the selector):

parentElement.querySelectorAll(':scope > *');

At the time of writing this :scope is supported in Chrome, Firefox and Safari.

javax.net.ssl.SSLException: Read error: ssl=0x9524b800: I/O error during system call, Connection reset by peer

If using Nginx and getting a similar problem, then this might help:

Scan your domain on this sslTesturl, and see if the connection is allowed for your device version.

If lower version devices(like < Android 4.4.2 etc) are not able to connect due to TLS support, then try adding this to your Nginx config file,

ssl_protocols TLSv1 TLSv1.1 TLSv1.2;

An efficient way to transpose a file in Bash

Have a look at GNU datamash which can be used like datamash transpose. A future version will also support cross tabulation (pivot tables)

Here is how you would do it with space separated columns:

datamash transpose -t ' ' < file > transposed_file

How to perform OR condition in django queryset?

from django.db.models import Q
User.objects.filter(Q(income__gte=5000) | Q(income__isnull=True))

via Documentation

UIView Infinite 360 degree rotation animation?

Nate's answer above is ideal for stop and start animation and gives a better control. I was intrigued why yours didn't work and his does. I wanted to share my findings here and a simpler version of the code that would animate a UIView continuously without stalling.

This is the code I used,

- (void)rotateImageView
{
    [UIView animateWithDuration:1 delay:0 options:UIViewAnimationOptionCurveLinear animations:^{
        [self.imageView setTransform:CGAffineTransformRotate(self.imageView.transform, M_PI_2)];
    }completion:^(BOOL finished){
        if (finished) {
            [self rotateImageView];
        }
    }];
}

I used 'CGAffineTransformRotate' instead of 'CGAffineTransformMakeRotation' because the former returns the result which is saved as the animation proceeds. This will prevent the jumping or resetting of the view during the animation.

Another thing is not to use 'UIViewAnimationOptionRepeat' because at the end of the animation before it starts repeating, it resets the transform making the view jump back to its original position. Instead of a repeat, you recurse so that the transform is never reset to the original value because the animation block virtually never ends.

And the last thing is, you have to transform the view in steps of 90 degrees (M_PI / 2) instead of 360 or 180 degrees (2*M_PI or M_PI). Because transformation occurs as a matrix multiplication of sine and cosine values.

t' =  [ cos(angle) sin(angle) -sin(angle) cos(angle) 0 0 ] * t

So, say if you use 180-degree transformation, the cosine of 180 yields -1 making the view transform in opposite direction each time (Note-Nate's answer will also have this issue if you change the radian value of transformation to M_PI). A 360-degree transformation is simply asking the view to remain where it was, hence you don't see any rotation at all.

How do I find if a string starts with another string in Ruby?

puts 'abcdefg'.start_with?('abc')  #=> true

[edit] This is something I didn't know before this question: start_with takes multiple arguments.

'abcdefg'.start_with?( 'xyz', 'opq', 'ab')

How to use org.apache.commons package?

Download commons-net binary from here. Extract the files and reference the commons-net-x.x.jar file.

How to use FormData in react-native?

This worked for me

var serializeJSON = function(data) {
  return Object.keys(data).map(function (keyName) {
    return encodeURIComponent(keyName) + '=' + encodeURIComponent(data[keyName])
  }).join('&');
}

var response = fetch(url, {
  method: 'POST',
  body: serializeJSON({
    haha: 'input'
  })
});

Nested attributes unpermitted parameters

If you use a JSONB field, you must convert it to JSON with .to_json (ROR)

What is a 'workspace' in Visual Studio Code?

On some investigation, the answer appears to be (a).

When I go to change the settings, the settings file goes into a .vscode directory in my project directory.

Print execution time of a shell command

If I'm starting a long-running process like a copy or hash and I want to know later how long it took, I just do this:

$ date; sha1sum reallybigfile.txt; date

Which will result in the following output:

Tue Jun  2 21:16:03 PDT 2015
5089a8e475cc41b2672982f690e5221469390bc0  reallybigfile.txt
Tue Jun  2 21:33:54 PDT 2015

Granted, as implemented here it isn't very precise and doesn't calculate the elapsed time. But it's dirt simple and sometimes all you need.

How do I get my C# program to sleep for 50 msec?

There are basically 3 choices for waiting in (almost) any programming language:

Loose waiting
- Executing thread blocks for given time (= does not consume processing power)
- No processing is possible on blocked/waiting thread
- Not so precise
Tight waiting (also called tight loop)
- processor is VERY busy for the entire waiting interval (in fact, it usually consumes 100% of one core's processing time)
- Some actions can be performed while waiting
- Very precise
Combination of previous 2
- It usually combines processing efficiency of 1. and preciseness + ability to do something of 2.

for 1. - Loose waiting in C#:

Thread.Sleep(numberOfMilliseconds);

However, windows thread scheduler causes acccuracy of Sleep() to be around 15ms (so Sleep can easily wait for 20ms, even if scheduled to wait just for 1ms).

for 2. - Tight waiting in C# is:

Stopwatch stopwatch = Stopwatch.StartNew();
while (true)
{
    //some other processing to do possible
    if (stopwatch.ElapsedMilliseconds >= millisecondsToWait)
    {
        break;
    }
}

We could also use DateTime.Now or other means of time measurement, but Stopwatch is much faster (and this would really become visible in tight loop).

for 3. - Combination:

Stopwatch stopwatch = Stopwatch.StartNew();
while (true)
{
    //some other processing to do STILL POSSIBLE
    if (stopwatch.ElapsedMilliseconds >= millisecondsToWait)
    {
        break;
    }
    Thread.Sleep(1); //so processor can rest for a while
}

This code regularly blocks thread for 1ms (or slightly more, depending on OS thread scheduling), so processor is not busy for that time of blocking and code does not consume 100% of processor's power. Other processing can still be performed in-between blocking (such as: updating of UI, handling of events or doing interaction/communication stuff).

How do you merge two Git repositories?

Similar to @Smar but uses file system paths, set in PRIMARY and SECONDARY:

PRIMARY=~/Code/project1
SECONDARY=~/Code/project2
cd $PRIMARY
git remote add test $SECONDARY && git fetch test
git merge test/master

Then you manually merge.

(adapted from post by Anar Manafov)

convert 12-hour hh:mm AM/PM to 24-hour hh:mm

For anybody reading this in the future, here is a simpler answer:

var s = "11:41:02PM";
var time = s.match(/\d{2}/g);
if (time[0] === "12") time[0] = "00";
if (s.indexOf("PM") > -1) time[0] = parseInt(time[0])+12;
return time.join(":");

What does "select count(1) from table_name" on any database tables mean?

There is no difference.

COUNT(1) is basically just counting a constant value 1 column for each row. As other users here have said, it's the same as COUNT(0) or COUNT(42). Any non-NULL value will suffice.

http://asktom.oracle.com/pls/asktom/f?p=100:11:2603224624843292::::P11_QUESTION_ID:1156151916789

The Oracle optimizer did apparently use to have bugs in it, which caused the count to be affected by which column you picked and whether it was in an index, so the COUNT(1) convention came into being.

How to find a value in an excel column by vba code Cells.Find

Just for sake of completeness, you can also use the same technique above with excel tables.

In the example below, I'm looking of a text in any cell of a Excel Table named "tblConfig", place in the sheet named Config that normally is set to be hidden. I'm accepting the defaults of the Find method.

Dim list As ListObject
Dim config As Worksheet
Dim cell as Range


Set config = Sheets("Config")
Set list = config.ListObjects("tblConfig")

'search in any cell of the data range of excel table
Set cell = list.DataBodyRange.Find(searchTerm)

If cell Is Nothing Then
    'when information is not found
Else
    'when information is found
End If

pandas python how to count the number of records or rows in a dataframe

The Nan example above misses one piece, which makes it less generic. To do this more "generically" use df['column_name'].value_counts() This will give you the counts of each value in that column.

d=['A','A','A','B','C','C'," " ," "," "," "," ","-1"] # for simplicity

df=pd.DataFrame(d)
df.columns=["col1"]
df["col1"].value_counts() 
      5
A     3
C     2
-1    1
B     1
dtype: int64
"""len(df) give you 12, so we know the rest must be Nan's of some form, while also having a peek into other invalid entries, especially when you might want to ignore them like -1, 0 , "", also"""

MySql : Grant read only options?

Even user has got answer and @Michael - sqlbot has covered mostly points very well in his post but one point is missing, so just trying to cover it.

If you want to provide read permission to a simple user (Not admin kind of)-

GRANT SELECT, EXECUTE ON DB_NAME.* TO 'user'@'localhost' IDENTIFIED BY 'PASSWORD';

Note: EXECUTE is required here, so that user can read data if there is a stored procedure which produce a report (have few select statements).

Replace localhost with specific IP from which user will connect to DB.

Additional Read Permissions are-

SHOW VIEW : If you want to show view schema.
REPLICATION CLIENT : If user need to check replication/slave status. But need to give permission on all DB.
PROCESS : If user need to check running process. Will work with all DB only.

Install an apk file from command prompt?

Press Win+R > cmd
Navigate to platform-tools\ in the android-sdk windows folder
Type adb
now follow the steps writte by Mohit Kanada (ensure that you mention the entire path of the .apk file for eg. d:\android-apps\test.apk)

Convert a space delimited string to list

try

states.split()

it returns the list

['Alaska',
 'Alabama',
 'Arkansas',
 'American',
 'Samoa',
 'Arizona',
 'California',
 'Colorado']

and this returns the random element of the list

import random
random.choice(states.split())

split statement parses the string and returns the list, by default it's divided into the list by spaces, if you specify the string it's divided by this string, so for example

states.split('Ari')

returns

['Alaska Alabama Arkansas American Samoa ', 'zona California Colorado']

Btw, list is in python interpretated with [] brackets instead of {} brackets, {} brackets are used for dictionaries, you can read more on this here

I see you are probably new to python, so I'd give you some advice how to use python's great documentation

Almost everything you need can be found here You can use also python included documentation, open python console and write help() If you don't know what to do with some object, I'd install ipython, write statement and press Tab, great tool which helps you with interacting with the language

I just wrote this here to show that python is great tool also because it's great documentation and it's really powerful to know this

Powershell Multidimensional Arrays

What is a raw type and why shouldn't we use it?

Raw types are fine when they express what you want to express.

For example, a deserialisation function might return a List, but it doesn't know the list's element type. So List is the appropriate return type here.

adb doesn't show nexus 5 device

Go here and download and unzip to an easy location:

http://developer.android.com/sdk/win-usb.html#top Download and install

Typescript empty object for a typed variable

Caveats

Here are two worthy caveats from the comments.

Either you want user to be of type User | {} or Partial<User>, or you need to redefine the User type to allow an empty object. Right now, the compiler is correctly telling you that user is not a User. – jcalz

I don't think this should be considered a proper answer because it creates an inconsistent instance of the type, undermining the whole purpose of TypeScript. In this example, the property Username is left undefined, while the type annotation is saying it can't be undefined. – Ian Liu Rodrigues

Answer

One of the design goals of TypeScript is to "strike a balance between correctness and productivity." If it will be productive for you to do this, use Type Assertions to create empty objects for typed variables.

type User = {
    Username: string;
    Email: string;
}

const user01 = {} as User;
const user02 = <User>{};

user01.Email = "[email protected]";

Here is a working example for you.

How to pass in parameters when use resource service?

I think I see your problem, you need to use the @ syntax to define parameters you will pass in this way, also I'm not sure what loginID or password are doing you don't seem to define them anywhere and they are not being used as URL parameters so are they being sent as query parameters?

This is what I can suggest based on what I see so far:

.factory('MagComments', function ($resource) {
    return $resource('http://localhost/dooleystand/ci/api/magCommenct/:id', {
      loginID : organEntity,
      password : organCommpassword,
      id : '@magId'
    });
  })

The @magId string will tell the resource to replace :id with the property magId on the object you pass it as parameters.

I'd suggest reading over the documentation here (I know it's a bit opaque) very carefully and looking at the examples towards the end, this should help a lot.

Regular Expression: Any character that is NOT a letter or number

To match anything other than letter or number or letter with diacritics like é you could try this:

[^\wÀ-úÀ-ÿ]

And to replace:

var str = 'dfj,dsf7é@lfsd .sdklfàj1';
str = str.replace(/[^\wÀ-úÀ-ÿ]/g, '_');

Inspired by the top post with support for diacritics

source

MongoDB distinct aggregation

You can use $addToSet with the aggregation framework to count distinct objects.

For example:

db.collectionName.aggregate([{
    $group: {_id: null, uniqueValues: {$addToSet: "$fieldName"}}
}])

Using module 'subprocess' with timeout

I added the solution with threading from jcollado to my Python module easyprocess.

Install:

pip install easyprocess

Example:

from easyprocess import Proc

# shell is not supported!
stdout=Proc('ping localhost').call(timeout=1.5).stdout
print stdout

What is the difference between Set and List?

A Set cannot contain duplicate elements while a List can. A List (in Java) also implies order.

Go Back to Previous Page

history.go(-1) this is a possible solution to the problem but it does not work in incognito mode as history is not maintained by the browser in this mode.

Google Chrome redirecting localhost to https

None of these worked for me. It started happening after a chrome update (Version 63.0.3239.84, linux) with a local URL. Would always redirect to https no matter what. Lost some hours and a lot of patience on this

What did worked after all was just changing the domain.

For what is worth, the domain was .app. Perhaps it got something to do? And just changed it to .test and chrome stopped redirecting it

Detecting when user scrolls to bottom of div with jQuery

Here's another version.

The key code is function scroller() which takes input as the height of the div containing the scrolling section, using overflow:scroll. It approximates 5px from the top or 10px from the bottom as at the top or bottom. Otherwise it's too sensitive. It seems 10px is about the minimum. You'll see it adds 10 to the div height to get the bottom height. I assume 5px might work, I didn't test extensively. YMMV. scrollHeight returns the height of the inner scrolling area, not the displayed height of the div, which in this case is 400px.

<?php

$scrolling_area_height=400;
echo '
<script type="text/javascript">
          function scroller(ourheight) {
            var ourtop=document.getElementById(\'scrolling_area\').scrollTop;
            if (ourtop > (ourheight-\''.($scrolling_area_height+10).'\')) {
                alert(\'at the bottom; ourtop:\'+ourtop+\' ourheight:\'+ourheight);
            }
            if (ourtop <= (5)) {
                alert(\'Reached the top\');
            }
          }
</script>

<style type="text/css">
.scroller { 
            display:block;
            float:left;
            top:10px;
            left:10px;
            height:'.$scrolling_area_height.';
            border:1px solid red;
            width:200px;
            overflow:scroll; 
        }
</style>

$content="your content here";

<div id="scrolling_area" class="scroller">
onscroll="var ourheight=document.getElementById(\'scrolling_area\').scrollHeight;
        scroller(ourheight);"
        >'.$content.'
</div>';

?>

console.log timestamps in Chrome?

You can use dev tools profiler.

console.time('Timer name');
//do critical time stuff
console.timeEnd('Timer name');

"Timer name" must be the same. You can use multiple instances of timer with different names.

Programs & Examples On #Nslock