Programs & Examples On #Proficy

How to check whether a string contains a substring in Ruby

Expanding on Clint Pachl's answer:

Regex matching in Ruby returns nil when the expression doesn't match. When it does, it returns the index of the character where the match happens. For example:

"foobar" =~ /bar/  # returns 3
"foobar" =~ /foo/  # returns 0
"foobar" =~ /zzz/  # returns nil

It's important to note that in Ruby only nil and the boolean expression false evaluate to false. Everything else, including an empty Array, empty Hash, or the Integer 0, evaluates to true.

That's why the /foo/ example above works, and why.

if "string" =~ /regex/

works as expected, only entering the 'true' part of the if block if a match occurred.

Getting rid of all the rounded corners in Twitter Bootstrap

When using Bootstrap >= 3.0 source files (SASS or LESS) you don't have to get rid of the rounded corners on everything if there is just one element that is bugging you, for example, to just get rid of the rounded corners on the navbar, use:

With SCSS:

$navbar-border-radius: 0;

With LESS:

@navbar-border-radius: 0;

However, if you do want to get rid of the rounded corners on everything, you can do what @adamwong246 mentioned and use:

$baseBorderRadius: 0;
@baseBorderRadius: 0;

Those two settings are the "root" settings from which the other settings like navbar-border-radius will inherit from unless other values are specified.

For a list all variables check out the variables.less or variables.scss

1067 error on attempt to start MySQL

I had the same problem. In my case, it was "user error" (although the Windows installer should have been smarter about it and prevented me from committing such an error).

During installation, if you make changes to the default installation paths, make sure you use the same paths for both the "Server data files" on the Custom Setup screen and then later in the "InnoDB Tablespace Settings" during the "MySQL Server Instance Configuration Wizard"

Windows.history.back() + location.reload() jquery

This is the correct answer. It will refresh the previous page.

window.location=document.referrer;

How to view .img files?

.IMG files are ususally filesystems, not pictures. The easiest way to access them is to install VMWare, install Windows in VMWare, and then add the .img file as some kind of disk device (floppy, cdrom, hard disk). If you guess the right kind, Windows might be able to open it.

Creating a file only if it doesn't exist in Node.js

As your intuition correctly guessed, the naive solution with a pair of exists / writeFile calls is wrong. Asynchronous code runs in unpredictable ways. And in given case it is

  • Is there a file a.txt? — No.
  • (File a.txt gets created by another program)
  • Write to a.txt if it's possible. — Okay.

But yes, we can do that in a single call. We're working with file system so it's a good idea to read developer manual on fs. And hey, here's an interesting part.

'w' - Open file for writing. The file is created (if it does not exist) or truncated (if it exists).

'wx' - Like 'w' but fails if path exists.

So all we have to do is just add wx to the fs.open call. But hey, we don't like fopen-like IO. Let's read on fs.writeFile a bit more.

fs.readFile(filename[, options], callback)#

filename String

options Object

encoding String | Null default = null

flag String default = 'r'

callback Function

That options.flag looks promising. So we try

fs.writeFile(path, data, { flag: 'wx' }, function (err) {
    if (err) throw err;
    console.log("It's saved!");
});

And it works perfectly for a single write. I guess this code will fail in some more bizarre ways yet if you try to solve your task with it. You have an atomary "check for a_#.jpg existence, and write there if it's empty" operation, but all the other fs state is not locked, and a_1.jpg file may spontaneously disappear while you're already checking a_5.jpg. Most* file systems are no ACID databases, and the fact that you're able to do at least some atomic operations is miraculous. It's very likely that wx code won't work on some platform. So for the sake of your sanity, use database, finally.

Some more info for the suffering

Imagine we're writing something like memoize-fs that caches results of function calls to the file system to save us some network/cpu time. Could we open the file for reading if it exists, and for writing if it doesn't, all in the single call? Let's take a funny look on those flags. After a while of mental exercises we can see that a+ does what we want: if the file doesn't exist, it creates one and opens it both for reading and writing, and if the file exists it does so without clearing the file (as w+ would). But now we cannot use it neither in (smth)File, nor in create(Smth)Stream functions. And that seems like a missing feature.

So feel free to file it as a feature request (or even a bug) to Node.js github, as lack of atomic asynchronous file system API is a drawback of Node. Though don't expect changes any time soon.

Edit. I would like to link to articles by Linus and by Dan Luu on why exactly you don't want to do anything smart with your fs calls, because the claim was left mostly not based on anything.

How to convert date in to yyyy-MM-dd Format?

Modern answer: Use LocalDate from java.time, the modern Java date and time API, and its toString method:

    LocalDate date = LocalDate.of(2012, Month.DECEMBER, 1); // get from somewhere
    String formattedDate = date.toString();
    System.out.println(formattedDate);

This prints

2012-12-01

A date (whether we’re talking java.util.Date or java.time.LocalDate) doesn’t have a format in it. All it’s got is a toString method that produces some format, and you cannot change the toString method. Fortunately, LocalDate.toString produces exactly the format you asked for.

The Date class is long outdated, and the SimpleDateFormat class that you tried to use, is notoriously troublesome. I recommend you forget about those classes and use java.time instead. The modern API is so much nicer to work with.

Except: it happens that you get a Date from a legacy API that you cannot change or don’t want to change just now. The best thing you can do with it is convert it to java.time.Instant and do any further operations from there:

    Date oldfashoinedDate = // get from somewhere
    LocalDate date = oldfashoinedDate.toInstant()
            .atZone(ZoneId.of("Asia/Beirut"))
            .toLocalDate();

Please substitute your desired time zone if it didn’t happen to be Asia/Beirut. Then proceed as above.

Link: Oracle tutorial: Date Time, explaining how to use java.time.

Auto detect mobile browser (via user-agent?)

Have you considered using css3 media queries? In most cases you can apply some css styles specifically for the targeted device without having to create a separate mobile version of the site.

@media screen and (max-width:1025px) {
   #content {
     width: 100%;
   }
}

You can set the width to whatever you want, but 1025 will catch the iPad landscape view.

You'll also want to add the following meta tag to your head:

<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1">

Check out this article over at HTML5 Rocks for some good examples

What is the copy-and-swap idiom?

This answer is more like an addition and a slight modification to the answers above.

In some versions of Visual Studio (and possibly other compilers) there is a bug that is really annoying and doesn't make sense. So if you declare/define your swap function like this:

friend void swap(A& first, A& second) {

    std::swap(first.size, second.size);
    std::swap(first.arr, second.arr);

}

... the compiler will yell at you when you call the swap function:

enter image description here

This has something to do with a friend function being called and this object being passed as a parameter.


A way around this is to not use friend keyword and redefine the swap function:

void swap(A& other) {

    std::swap(size, other.size);
    std::swap(arr, other.arr);

}

This time, you can just call swap and pass in other, thus making the compiler happy:

enter image description here


After all, you don't need to use a friend function to swap 2 objects. It makes just as much sense to make swap a member function that has one other object as a parameter.

You already have access to this object, so passing it in as a parameter is technically redundant.

js window.open then print()

Turgut gave the right solution. Just for clarity, you need to add close after writing.

function openWin()
  {
    myWindow=window.open('','','width=200,height=100');
    myWindow.document.write("<p>This is 'myWindow'</p>");


    myWindow.document.close(); //missing code


    myWindow.focus();
    myWindow.print(); 
  }

How to update a claim in ASP.NET Identity?

when I use MVC5, and add the claim here.

public async Task<ClaimsIdentity> GenerateUserIdentityAsync(PATAUserManager manager)
    {
        // Note the authenticationType must match the one defined in CookieAuthenticationOptions.AuthenticationType
        var userIdentity = await manager.CreateIdentityAsync(this, DefaultAuthenticationTypes.ApplicationCookie);
        // Add custom user claims here
        userIdentity.AddClaim(new Claim(ClaimTypes.Role, this.Role));

        return userIdentity;
    }

when I'm check the claim result in the SignInAsync function,i can't get the role value use anyway. But...

after this request finished, I can access Role in other action(anther request).

 var userWithClaims = (ClaimsPrincipal)User;
        Claim CRole = userWithClaims.Claims.First(c => c.Type == ClaimTypes.Role);

so, i think maybe asynchronous cause the IEnumerable updated behind the process.

How to use the pass statement?

A common use case where it can be used 'as is' is to override a class just to create a type (which is otherwise the same as the superclass), e.g.

class Error(Exception):
    pass

So you can raise and catch Error exceptions. What matters here is the type of exception, rather than the content.

How can I make a link from a <td> table cell

I'd like to make the entire td a hyperlink. I'd prefer without javascript. Is this possible?

That's not possible without javascript. Also, that won't be semantic markup. You should use link instead otherwise it is a matter of attaching onclick handler to <td> to redirect to some other page.

How to define an optional field in protobuf 3

Since protobuf release 3.15, proto3 supports using the optional keyword (just as in proto2) to give a scalar field presence information.

syntax = "proto3";

message Foo {
    int32 bar = 1;
    optional int32 baz = 2;
}

A has_baz()/hasBaz() method is generated for the optional field above, just as it was in proto2.

Under the hood, protoc effectively treats an optional field as if it were declared using a oneof wrapper, as CyberSnoopy’s answer suggested:

message Foo {
    int32 bar = 1;
    oneof optional_baz {
        int32 baz = 2;
    }
}

If you’ve already used that approach, you can now simplify your message declarations (switch from oneof to optional) and code, since the wire format is the same.

The nitty-gritty details about field presence and optional in proto3 can be found in the Application note: Field presence doc.

Historical note: Experimental support for optional in proto3 was first announced on Apr 23, 2020 in this comment. Using it required passing protoc the --experimental_allow_proto3_optional flag in releases 3.12-3.14.

Setting Column width in Apache POI

With Scala there is a nice Wrapper spoiwo

You can do it like this:

Workbook(mySheet.withColumns(
      Column(autoSized = true),
      Column(width = new Width(100, WidthUnit.Character)),
      Column(width = new Width(100, WidthUnit.Character)))
    )

RandomForestClassfier.fit(): ValueError: could not convert string to float

LabelEncoding worked for me (basically you've to encode your data feature-wise) (mydata is a 2d array of string datatype):

myData=np.genfromtxt(filecsv, delimiter=",", dtype ="|a20" ,skip_header=1);

from sklearn import preprocessing
le = preprocessing.LabelEncoder()
for i in range(*NUMBER OF FEATURES*):
    myData[:,i] = le.fit_transform(myData[:,i])

How to set full calendar to a specific start date when it's initialized for the 1st time?

In version 2.1.1 this works :

$('#calendar').fullCalendar({
// your calendar settings...
});

$('#calendar').fullCalendar('gotoDate', '2014-05-01');

Documentation about moment time/date format : http://fullcalendar.io/docs/utilities/Moment/ Documentation about the upgrades in version 2 : https://github.com/arshaw/fullcalendar/wiki/Upgrading-to-v2

Adding a default value in dropdownlist after binding with database

The solution provided by Justin should work. To be sure making use of SelectedIndex property will also help.

ddlColor.DataSource = from p in db.ProductTypes
                      where p.ProductID == pID
                      orderby p.Color
                      select new { p.Color };

ddlColor.DataTextField = "Color";
ddlColor.DataBind();

ddlColor.Items.Insert(0, new ListItem("Select Color", ""); 
ddlColor.SelectedIndex = 0;

Adding a newline character within a cell (CSV)

I was concatenating the variable and adding multiple items in same row. so below code work for me. "\n" new line code is mandatory to add first and last of each line if you will add it on last only it will append last 1-2 character to new lines.

  $itemCode =  '';
foreach($returnData['repairdetail'] as $checkkey=>$repairDetailData){

    if($checkkey >0){
        $itemCode   .= "\n".trim(@$repairDetailData['ItemMaster']->Item_Code)."\n";
    }else{
        $itemCode   .= "\n".trim(@$repairDetailData['ItemMaster']->Item_Code)."\n";             
    }
    $repairDetaile[]= array(
        $itemCode,
    )
}
// pass all array to here 
foreach ($repairDetaile as $csvData) { 
    fputcsv($csv_file,$csvData,',','"');
}
fclose($csv_file);  

How to give environmental variable path for file appender in configuration file in log4j

To dynamically change a variable you can do something like this:

String value = System.getenv("MY_HOME");
Properties prop = new Properties("log4j.properties"); 
prop.put("MY_HOME", value); // overwrite with value from environment
PropertyConfigurator.configure(prop);

Can anyone explain IEnumerable and IEnumerator to me?

I have noticed these differences:

A. We iterate the list in different way, foreach can be used for IEnumerable and while loop for IEnumerator.

B. IEnumerator can remember the current index when we pass from one method to another (it start working with current index) but IEnumerable can't remember the index and it reset the index to beginning. More in this video https://www.youtube.com/watch?v=jd3yUjGc9M0

How to test the type of a thrown exception in Jest

In case you are working with Promises:

await expect(Promise.reject(new HttpException('Error message', 402)))
  .rejects.toThrowError(HttpException);

Stretch horizontal ul to fit width of div

I Hope that this helps you out... Because I tried all the answers but nothing worked perfectly. So, I had to come up with a solution on my own.

#horizontal-style {
  padding-inline-start: 0 !important; // Just in case if you find that there is an extra padding at the start of the line 
  justify-content: space-around;
  display: flex;
}

#horizontal-style a {
    text-align: center;
    color: white;
    text-decoration: none;
}

How to determine the Boost version on a system?

If one installed boost on macOS via Homebrew, one is likely to see the installed boost version(s) with:

ls /usr/local/Cellar/boost*

What is the difference between the kernel space and the user space?

The maximum size of address space depends on the length of the address register on the CPU.

On systems with 32-bit address registers, the maximum size of address space is 232 bytes, or 4 GiB. Similarly, on 64-bit systems, 264 bytes can be addressed.

Such address space is called virtual memory or virtual address space. It is not actually related to physical RAM size.

On Linux platforms, virtual address space is divided into kernel space and user space.

An architecture-specific constant called task size limit, or TASK_SIZE, marks the position where the split occurs:

  • the address range from 0 up to TASK_SIZE-1 is allotted to user space;

  • the remainder from TASK_SIZE up to 232-1 (or 264-1) is allotted to kernel space.

On a particular 32-bit system for example, 3 GiB could be occupied for user space and 1 GiB for kernel space.

Each application/program in a Unix-like operating system is a process; each of those has a unique identifier called Process Identifier (or simply Process ID, i.e. PID). Linux provides two mechanisms for creating a process: 1. the fork() system call, or 2. the exec() call.

A kernel thread is a lightweight process and also a program under execution. A single process may consist of several threads sharing the same data and resources but taking different paths through the program code. Linux provides a clone() system call to generate threads.

Example uses of kernel threads are: data synchronization of RAM, helping the scheduler to distribute processes among CPUs, etc.

Displaying the Error Messages in Laravel after being Redirected from controller

A New Laravel Blade Error Directive comes to Laravel 5.8.13

// Before
@if ($errors->has('email'))
    <span>{{ $errors->first('email') }}</span>
@endif

// After:
@error('email')
    <span>{{ $message }}</span>
@enderror

How can I make text appear on next line instead of overflowing?

Well, you can stick one or more "soft hyphens" (&#173;) in your long unbroken strings. I doubt that old IE versions deal with that correctly, but what it's supposed to do is tell the browser about allowable word breaks that it can use if it has to.

Now, how exactly would you pick where to stuff those characters? That depends on the actual string and what it means, I guess.

Android XML Percent Symbol

This could be a case of the IDE becoming too strict.

The idea is sound, in general you should specify the order of substitution variables so that should you add resources for another language, your java code will not need to be changed. However there are two issues with this:

Firstly, a string such as:

You will need %.5G %s

to be used as You will need 2.1200 mg will have the order the same in any language as that amount of mass is always represented in that order scientifically.

The second is that if you put the order of variables in what ever language your default resources are specified in (eg English) then you only need to specify the positions in the resource strings for languages the use a different order to your default language.

The good news is that this is simple to fix. Even though there is no need to specify the positions, and the IDE is being overly strict, just specify them anyway. For the example above use:

You will need %1$.5G %2$s

Linq UNION query to select two elements

EDIT:

Ok I found why the int.ToString() in LINQtoEF fails, please read this post: Problem with converting int to string in Linq to entities

This works on my side :

        List<string> materialTypes = (from u in result.Users
                                      select u.LastName)
                       .Union(from u in result.Users
                               select SqlFunctions.StringConvert((double) u.UserId)).ToList();

On yours it should be like this:

    IList<String> materialTypes = ((from tom in context.MaterialTypes
                                       where tom.IsActive == true
                                       select tom.Name)
                                       .Union(from tom in context.MaterialTypes
                                       where tom.IsActive == true
                                       select SqlFunctions.StringConvert((double)tom.ID))).ToList();

Thanks, i've learnt something today :)

How can I use regex to get all the characters after a specific character, e.g. comma (",")

This should work

preg_match_all('@.*\,(.*)@', '{{your data}}', $arr, PREG_PATTERN_ORDER);

You can test it here: http://www.spaweditor.com/scripts/regex/index.php

RegEx: .*\,(.*)

Same RegEx test here for JavaScript: http://www.regular-expressions.info/javascriptexample.html

Transition color fade on hover?

For having a trasition effect like a highlighter just to highlight the text and fade off the bg color, we used the following:

_x000D_
_x000D_
.field-error {_x000D_
    color: #f44336;_x000D_
    padding: 2px 5px;_x000D_
    position: absolute;_x000D_
    font-size: small;_x000D_
    background-color: white;_x000D_
}_x000D_
_x000D_
.highlighter {_x000D_
    animation: fadeoutBg 3s; /***Transition delay 3s fadeout is class***/_x000D_
    -moz-animation: fadeoutBg 3s; /* Firefox */_x000D_
    -webkit-animation: fadeoutBg 3s; /* Safari and Chrome */_x000D_
    -o-animation: fadeoutBg 3s; /* Opera */_x000D_
}_x000D_
_x000D_
@keyframes fadeoutBg {_x000D_
    from { background-color: lightgreen; } /** from color **/_x000D_
    to { background-color: white; } /** to color **/_x000D_
}_x000D_
_x000D_
@-moz-keyframes fadeoutBg { /* Firefox */_x000D_
    from { background-color: lightgreen; }_x000D_
    to { background-color: white; }_x000D_
}_x000D_
_x000D_
@-webkit-keyframes fadeoutBg { /* Safari and Chrome */_x000D_
    from { background-color: lightgreen; }_x000D_
    to { background-color: white; }_x000D_
}_x000D_
_x000D_
@-o-keyframes fadeoutBg { /* Opera */_x000D_
    from { background-color: lightgreen; }_x000D_
    to { background-color: white; }_x000D_
}
_x000D_
<div class="field-error highlighter">File name already exists.</div>
_x000D_
_x000D_
_x000D_

How do I execute code AFTER a form has loaded?

I had the same problem, and solved it as follows:

Actually I want to show Message and close it automatically after 2 second. For that I had to generate (dynamically) simple form and one label showing message, stop message for 1500 ms so user read it. And Close dynamically created form. Shown event occur After load event. So code is

Form MessageForm = new Form();
MessageForm.Shown += (s, e1) => { 
    Thread t = new Thread(() => Thread.Sleep(1500)); 
    t.Start(); 
    t.Join(); 
    MessageForm.Close(); 
};

Check if an excel cell exists on another worksheet in a column - and return the contents of a different column

You can use following formulas.

For Excel 2007 or later:

=IFERROR(VLOOKUP(D3,List!A:C,3,FALSE),"No Match")

For Excel 2003:

=IF(ISERROR(MATCH(D3,List!A:A, 0)), "No Match", VLOOKUP(D3,List!A:C,3,FALSE))

Note, that

  • I'm using List!A:C in VLOOKUP and returns value from column ? 3
  • I'm using 4th argument for VLOOKUP equals to FALSE, in that case VLOOKUP will only find an exact match, and the values in the first column of List!A:C do not need to be sorted (opposite to case when you're using TRUE).

Error: Expression must have integral or unscoped enum type

Your variable size is declared as: float size;

You can't use a floating point variable as the size of an array - it needs to be an integer value.

You could cast it to convert to an integer:

float *temp = new float[(int)size];

Your other problem is likely because you're writing outside of the bounds of the array:

   float *temp = new float[size];

    //Getting input from the user
    for (int x = 1; x <= size; x++){
        cout << "Enter temperature " << x << ": ";

        // cin >> temp[x];
        // This should be:
        cin >> temp[x - 1];
    }

Arrays are zero based in C++, so this is going to write beyond the end and never write the first element in your original code.

How do I jump out of a foreach loop in C#?

Either return straight out of the loop:

foreach(string s in sList){
   if(s.equals("ok")){
      return true;
   }
}

// if you haven't returned by now, no items are "ok"
return false;

Or use break:

bool isOk = false;
foreach(string s in sList){
   if(s.equals("ok")){
      isOk = true;
      break; // jump out of the loop
   }
}

if(isOk)
{
    // do something
}

However, in your case it might be better to do something like this:

if(sList.Contains("ok"))
{
    // at least one element is "ok"
}
else
{
   // no elements are "ok"
}

Java: How to Indent XML Generated by Transformer

Neither of the suggested solutions worked for me. So I kept on searching for an alternative solution, which ended up being a mixture of the two before mentioned and a third step.

  1. set the indent-number into the transformerfactory
  2. enable the indent in the transformer
  3. wrap the otuputstream with a writer (or bufferedwriter)
//(1)
TransformerFactory tf = TransformerFactory.newInstance();
tf.setAttribute("indent-number", new Integer(2));

//(2)
Transformer t = tf.newTransformer();
t.setOutputProperty(OutputKeys.INDENT, "yes");

//(3)
t.transform(new DOMSource(doc),
new StreamResult(new OutputStreamWriter(out, "utf-8"));

You must do (3) to workaround a "buggy" behavior of the xml handling code.

Source: johnnymac75 @ http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6296446

(If I have cited my source incorrectly please let me know)

How to get ASCII value of string in C#

string s = "9quali52ty3";
foreach(char c in s)
{
  Console.WriteLine((int)c);
}

How do I find which application is using up my port?

How about netstat?

http://support.microsoft.com/kb/907980

The command is netstat -anob.

(Make sure you run command as admin)

I get:

C:\Windows\system32>netstat -anob

Active Connections

     Proto  Local Address          Foreign Address        State           PID
  TCP           0.0.0.0:80                0.0.0.0:0                LISTENING         4
 Can not obtain ownership information

  TCP    0.0.0.0:135            0.0.0.0:0              LISTENING       692
  RpcSs
 [svchost.exe]

  TCP    0.0.0.0:443            0.0.0.0:0              LISTENING       7540
 [Skype.exe]

  TCP    0.0.0.0:445            0.0.0.0:0              LISTENING       4
 Can not obtain ownership information
  TCP    0.0.0.0:623            0.0.0.0:0              LISTENING       564
 [LMS.exe]

  TCP    0.0.0.0:912            0.0.0.0:0              LISTENING       4480
 [vmware-authd.exe]

And If you want to check for the particular port, command to use is: netstat -aon | findstr 8080 from the same path

How do I address unchecked cast warnings?

Here's one way I handle this when I override the equals() operation.

public abstract class Section<T extends Section> extends Element<Section<T>> {
    Object attr1;

    /**
    * Compare one section object to another.
    *
    * @param obj the object being compared with this section object
    * @return true if this section and the other section are of the same
    * sub-class of section and their component fields are the same, false
    * otherwise
    */       
    @Override
    public boolean equals(Object obj) {
        if (obj == null) {
            // this exists, but obj doesn't, so they can't be equal!
            return false;
        }

        // prepare to cast...
        Section<?> other;

        if (getClass() != obj.getClass()) {
            // looks like we're comparing apples to oranges
            return false;
        } else {
            // it must be safe to make that cast!
            other = (Section<?>) obj;
        }

        // and then I compare attributes between this and other
        return this.attr1.equals(other.attr1);
    }
}

This seems to work in Java 8 (even compiled with -Xlint:unchecked)

Output PowerShell variables to a text file

Use this:

"$computer, $Speed, $Regcheck" | out-file -filepath C:\temp\scripts\pshell\dump.txt -append -width 200

How to update values in a specific row in a Python Pandas DataFrame?

So first of all, pandas updates using the index. When an update command does not update anything, check both left-hand side and right-hand side. If you don't update the indices to follow your identification logic, you can do something along the lines of

>>> df.loc[df.filename == 'test2.dat', 'n'] = df2[df2.filename == 'test2.dat'].loc[0]['n']
>>> df
Out[331]: 
    filename   m     n
0  test0.dat  12  None
1  test2.dat  13    16

If you want to do this for the whole table, I suggest a method I believe is superior to the previously mentioned ones: since your identifier is filename, set filename as your index, and then use update() as you wanted to. Both merge and the apply() approach contain unnecessary overhead:

>>> df.set_index('filename', inplace=True)
>>> df2.set_index('filename', inplace=True)
>>> df.update(df2)
>>> df
Out[292]: 
            m     n
filename           
test0.dat  12  None
test2.dat  13    16

How do you underline a text in Android XML?

Use this:

TextView txt = (TextView) findViewById(R.id.Textview1);
txt.setPaintFlags(txt.getPaintFlags() | Paint.UNDERLINE_TEXT_FLAG);

Disable Required validation attribute under certain circumstances

AFAIK you can not remove attribute at runtime, but only change their values (ie: readonly true/false) look here for something similar . As another way of doing what you want without messing with attributes I will go with a ViewModel for your specific action so you can insert all the logic without breaking the logic needed by other controllers. If you try to obtain some sort of wizard (a multi steps form) you can instead serialize the already compiled fields and with TempData bring them along your steps. (for help in serialize deserialize you can use MVC futures)

Generating unique random numbers (integers) between 0 and 'x'

Here's a simple, one-line solution:

var limit = 10;
var amount = 3;

randoSequence(1, limit).slice(0, amount);

It uses randojs.com to generate a randomly shuffled array of integers from 1 through 10 and then cuts off everything after the third integer. If you want to use this answer, toss this within the head tag of your HTML document:

<script src="https://randojs.com/1.0.0.js"></script>

jquery input select all on focus

The problem with most of these solutions is that they do not work correctly when changing the cursor position within the input field.

The onmouseup event changes the cursor position within the field, which is fired after onfocus (at least within Chrome and FF). If you unconditionally discard the mouseup then the user cannot change the cursor position with the mouse.

function selectOnFocus(input) {
    input.each(function (index, elem) {
        var jelem = $(elem);
        var ignoreNextMouseUp = false;

        jelem.mousedown(function () {
            if (document.activeElement !== elem) {
                ignoreNextMouseUp = true;
            }
        });
        jelem.mouseup(function (ev) {
            if (ignoreNextMouseUp) {
                ev.preventDefault();
                ignoreNextMouseUp = false;
            }
        });
        jelem.focus(function () {
            jelem.select();
        });
    });
}
selectOnFocus($("#myInputElement"));

The code will conditionally prevent the mouseup default behaviour if the field does not currently have focus. It works for these cases:

  • clicking when field is not focused
  • clicking when field has focus
  • tabbing into the field

I have tested this within Chrome 31, FF 26 and IE 11.

How can I make a JPA OneToOne relation lazy

The basic idea behing the XToOnes in Hibernate is that they are not lazy in most case.

One reason is that, when Hibernate have to decide to put a proxy (with the id) or a null,
it has to look into the other table anyway to join. The cost of accessing the other table in the database is significant, so it might as well fetch the data for that table at that moment (non-lazy behaviour), instead of fetching that in a later request that would require a second access to the same table.

Edited: for details, please refer to ChssPly76 's answer. This one is less accurate and detailed, it has nothing to offer. Thanks ChssPly76.

vba: get unique values from array

If the order of the deduplicated array does not matter to you, you can use my pragmatic function:

Function DeDupArray(ia() As String)
  Dim newa() As String
  ReDim newa(999)
  ni = -1
  For n = LBound(ia) To UBound(ia)
    dup = False
    If n <= UBound(ia) Then
      For k = n + 1 To UBound(ia)
        If ia(k) = ia(n) Then dup = True
      Next k

      If dup = False And Trim(ia(n)) <> "" Then
        ni = ni + 1
        newa(ni) = ia(n)
      End If
    End If
  Next n

  If ni > -1 Then
    ReDim Preserve newa(ni)
  Else
    ReDim Preserve newa(1)
  End If

  DeDupArray = newa
End Function



Sub testdedup()
Dim m(5) As String
Dim m2() As String

m(0) = "Horse"
m(1) = "Cow"
m(2) = "Dear"
m(3) = "Horse"
m(4) = "Joke"
m(5) = "Cow"

m2 = DeDupArray(m)
t = ""
For n = LBound(m2) To UBound(m2)
  t = t & n & "=" & m2(n) & " "
Next n
MsgBox t
End Sub

From the test function, it will result in the following deduplicated array:

"0=Dear 1=Horse 2=Joke 3=Cow "

How to use Select2 with JSON via Ajax request?

If ajax request is not fired, please check the select2 class in the select element. Removing the select2 class will fix that issue.

Column "invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause"

Put in other words, this error is telling you that SQL Server does not know which B to select from the group.

Either you want to select one specific value (e.g. the MIN, SUM, or AVG) in which case you would use the appropriate aggregate function, or you want to select every value as a new row (i.e. including B in the GROUP BY field list).


Consider the following data:

ID  A   B
1   1  13
1   1  79
1   2  13
1   2  13
1   2  42

The query

SELECT A, COUNT(B) AS T1 
FROM T2 
GROUP BY A

would return:

A  T1
1  2
2  3

which is all well and good.

However consider the following (illegal) query, which would produce this error:

SELECT A, COUNT(B) AS T1, B 
FROM T2 
GROUP BY A

And its returned data set illustrating the problem:

A  T1  B
1  2   13? 79? Both 13 and 79 as separate rows? (13+79=92)? ...?
2  3   13? 42? ...?

However, the following two queries make this clear, and will not cause the error:

  1. Using an aggregate

    SELECT A, COUNT(B) AS T1, SUM(B) AS B
    FROM T2
    GROUP BY A
    

    would return:

    A  T1  B
    1  2   92
    2  3   68
    
  2. Adding the column to the GROUP BY list

    SELECT A, COUNT(B) AS T1, B
    FROM T2
    GROUP BY A, B
    

    would return:

    A  T1  B
    1  1   13
    1  1   79
    2  2   13
    2  1   42
    

How to deploy a war file in JBoss AS 7?

I built the following ant-task for deployment based on the jboss deployment docs:

<target name="deploy" depends="jboss.environment, buildwar">
    <!-- Build path for deployed war-file -->
    <property name="deployed.war" value="${jboss.home}/${jboss.deploy.dir}/${war.filename}" />

    <!-- remove current deployed war -->
    <delete file="${deployed.war}.deployed" failonerror="false" />
    <waitfor maxwait="10" maxwaitunit="second">
        <available file="${deployed.war}.undeployed" />
    </waitfor>
    <delete dir="${deployed.war}" />

    <!-- copy war-file -->
    <copy file="${war.filename}" todir="${jboss.home}/${jboss.deploy.dir}" />

    <!-- start deployment -->
    <echo>start deployment ...</echo>
    <touch file="${deployed.war}.dodeploy" />

    <!-- wait for deployment to complete -->
    <waitfor maxwait="10" maxwaitunit="second">
        <available file="${deployed.war}.deployed" />
    </waitfor>
    <echo>deployment ok!</echo>
</target>

${jboss.deploy.dir} is set to standalone/deployments

Check If array is null or not in php

I understand what you want. You want to check every data of the array if all of it is empty or at least 1 is not empty

Empty array

Array ( [Tags] => SimpleXMLElement Object ( [0] => ) )

Not an Empty array

Array ( [Tags] => SimpleXMLElement Object ( [0] =>,[1] => "s" ) )


I hope I am right. You can use this function to check every data of an array if at least 1 of them has a value.

/*
 return true if the array is not empty
 return false if it is empty
*/
function is_array_empty($arr){
  if(is_array($arr)){     
      foreach($arr $key => $value){
          if(!empty($value) || $value != NULL || $value != ""){
              return true;
              break;//stop the process we have seen that at least 1 of the array has value so its not empty
          }
      }
      return false;
  }
}

if(is_array_empty($result['Tags'])){
    //array is not empty
}else{
    //array is empty
}

Hope that helps.

How to use GOOGLEFINANCE(("CURRENCY:EURAUD")) function

=INDEX(GoogleFinance("CURRENCY:" & "EUR" & "USD", "price", A2), 2, 2)

where A2 is the cell with a date formatted as date.

Replace "EUR" and "USD" with your currency pair.

GitLab remote: HTTP Basic: Access denied and fatal Authentication

GO TO C:\Users\<<USER>> AND DELETE THE .gitconfig file then try a command that connects to upstream like git clone, git pull or git push. You will be prompted to re-enter your credentials. Kindly do so.

How to visualize an XML schema?

There is a new free-to-use webtool, where you can view any xml schema:

Online XML Schema Viewer

www.xml-tools.net

It's written completely in JavaScript, so it's running in most modern browsers.

Variable that has the path to the current ansible-playbook that is executing?

I was using a playbook like this to test my roles locally:

---
- hosts: localhost
  roles:
     - role: .

but this stopped working with Ansible v2.2.

I debugged the aforementioned solution of

---
- hosts: all
  tasks:
    - name: Find out playbooks path
      shell: pwd
      register: playbook_path_output
    - debug: var=playbook_path_output.stdout

and it produced my home directory and not the "current working directory"

I settled with

---
- hosts: all
  roles:
    - role: '{{playbook_dir}}'

per the solution above.

Play multiple CSS animations at the same time

You cannot play two animations since the attribute can be defined only once. Rather why don't you include the second animation in the first and adjust the keyframes to get the timing right?

_x000D_
_x000D_
.image {_x000D_
    position: absolute;_x000D_
    top: 50%;_x000D_
    left: 50%;_x000D_
    width: 120px;_x000D_
    height: 120px;_x000D_
    margin:-60px 0 0 -60px;_x000D_
    -webkit-animation:spin-scale 4s linear infinite;_x000D_
}_x000D_
_x000D_
@-webkit-keyframes spin-scale { _x000D_
    50%{_x000D_
        transform: rotate(360deg) scale(2);_x000D_
    }_x000D_
    100% { _x000D_
        transform: rotate(720deg) scale(1);_x000D_
    } _x000D_
}
_x000D_
<img class="image" src="http://makeameme.org/media/templates/120/grumpy_cat.jpg" alt="" width="120" height="120">
_x000D_
_x000D_
_x000D_

Changing image on hover with CSS/HTML

What I usually do is that I create a double image with both states, acting like kind of a two-frame film which I then use with as background for the original element so that the element has width / height set in pixels, resulting in showing only one half of the image. Then what the hover state defines is basically "move the film to show the other frame".

For example, imagine that the image has to be a gray Tux, that we need to change to colorful Tux on hover. And the "hosting" element is a span with id "tuxie".

  1. I create 50 x 25 image with two Tuxes, one in color and other gray,
  2. then assign the image as a background for a 25 x 25 span,
  3. and finally set the hover to simply move the background 25px left.

The minimal code:

<style>
    #tuxie {
        width: 25px; height: 25px;
        background: url('images/tuxie.png') no-repeat left top;
    }
    #tuxie:hover { background-position: -25px 0px }
</style>

<div id="tuxie" />

and the image:

Two-frame Tuxie "film"

Advantages are:

  • By putting both frames in one file, it's ensured that they are loaded at once. This avoids the ugly glitch on slower connections when the other frame never loads immediately, so first hover never works properly.

  • It may be easier to manage your images this way since "paired" frames are never confused.

  • With smart use of Javascript or CSS selector, one can extend this and include even more frames in one file.

    In theory you could put even multiple buttons in single file and govern their display by coordinates, although such approach could get quickly out of hand.

Note that this is built with background CSS property, so if you really need to use with <img />s, you must not set the src property since that overlaps the background. (Come to think that clever use of transparency here could lead to interesting results, but probably very dependent on quality of image as well as of the engine.).

"document.getElementByClass is not a function"

I tried

Document.getElementsByClassName('option0')

Which resulted in the error: Uncaught TypeError: Document.getElementsByClass is not a function

After that I tried:

document.getElementsByClassName('option0')

And it works!

Ruby on Rails generates model field:type - what are the options for field:type?

To create a model that references another, use the Ruby on Rails model generator:

$ rails g model wheel car:references

That produces app/models/wheel.rb:

class Wheel < ActiveRecord::Base
  belongs_to :car
end

And adds the following migration:

class CreateWheels < ActiveRecord::Migration
  def self.up
    create_table :wheels do |t|
      t.references :car

      t.timestamps
    end
  end

  def self.down
    drop_table :wheels
  end
end

When you run the migration, the following will end up in your db/schema.rb:

$ rake db:migrate

create_table "wheels", :force => true do |t|
  t.integer  "car_id"
  t.datetime "created_at"
  t.datetime "updated_at"
end

As for documentation, a starting point for rails generators is Ruby on Rails: A Guide to The Rails Command Line which points you to API Documentation for more about available field types.

HTTP status code 0 - Error Domain=NSURLErrorDomain?

We got the error:

GET http://localhost/pathToWebSite/somePage.aspx raised an http.status: 0 error

That call is made from windows task that calls a VBS file, so to troubleshoot the problem, pointed a browser to the url and we get a Privacy Error:

Your connection is not private

Attackers might be trying to steal your information from localhost (for example, passwords, messages, or credit cards). NET::ERR_CERT_COMMON_NAME_INVALID

Automatically report details of possible security incidents to Google. Privacy policy Back to safety This server could not prove that it is localhost; its security certificate is from *.ourdomain.com. This may be caused by a misconfiguration or an attacker intercepting your connection. Learn more.

This is because we have a IIS URL Rewrite rule set to force connections use https. That rule diverts http://localhost to https://localhost but our SSL certificate is based on an outside facing domain name not localhost, thus the error which is reported as status code 0. So a Privacy error could be a very obscure reason for this status code 0.

In our case the solution was to add an exception to the rule for localhost and allow http://localhost/pathToWebSite/somePage.aspx to use http. Obscure, yes, but I'll run into this next year and now I'll find my answer in a google search.

html text input onchange event

When I'm doing something like this I use the onKeyUp event.

<script type="text/javascript">
 function bar() {
      //do stuff
 }
<input type="text" name="foo" onKeyUp="return bar()" />

but if you don't want to use an HTML event you could try to use jQuerys .change() method

$('.target').change(function() {
   //do stuff
});

in this example, the input would have to have a class "target"

if you're going to have multiple text boxes that you want to have done the same thing when their text is changed and you need their data then you could do this:

$('.target').change(function(event) {
   //do stuff with the "event" object as the object that called the method
)};

that way you can use the same code, for multiple text boxes using the same class without having to rewrite any code.

Laravel Query Builder where max id

For objects you can nest the queries:

DB::table('orders')->find(DB::table('orders')->max('id'));

So the inside query looks up the max id in the table and then passes that to the find, which gets you back the object.

git stash apply version

The keys into the stash are actually the stash@{n} items on the left. So try:

git stash apply stash@{0}

(note that in some shells you need to quote "stash@{0}", like zsh, fish and powershell).

Since version 2.11, it's pretty easy, you can use the N stack number instead of using stash@{n}. So now instead of using:

git stash apply "stash@{n}"

You can type:

git stash apply n

To get list of stashes:

git stash list

In fact stash@{0} is a revision in git that you can switch to... but git stash apply ... should figure out how to DTRT to apply it to your current location.

How to switch text case in visual studio code

Now an uppercase and lowercase switch can be done simultaneously in the selected strings via a regular expression replacement (regex, CtrlH + AltR), according to v1.47.3 June 2020 release:

Replacing different text cases in one selection

This is done through 4 "Single character" character classes (Perl documentation), namely, for the matched group following it:

  • \l <=> [[:lower:]]: first character becomes lowercase
  • \u <=> [[:upper:]]: first character becomes uppercase
  • \L <=> [^[:lower:]]: all characters become lowercase
  • \U <=> [^[:upper:]]: all characters become uppercase

$0 matches all selected groups, while $1 matches the 1st group, $2 the 2nd one, etc.

Hit the Match Case button at the left of the search bar (or AltC) and, borrowing some examples from an old Sublime Text answer, now this is possible:

  1. Capitalize words
  • Find: (\s)([a-z]) (\s matches spaces and new lines, i.e. " venuS" => " VenuS")
  • Replace: $1\u$2
  1. Uncapitalize words
  • Find: (\s)([A-Z])
  • Replace: $1\l$2
  1. Remove a single camel case (e.g. cAmelCAse => camelcAse => camelcase)
  • Find: ([a-z])([A-Z])
  • Replace: $1\l$2
  1. Lowercase all from an uppercase letter within words (e.g. LowerCASe => Lowercase)
  • Find: (\w)([A-Z]+)
  • Replace: $1\L$2
  • Alternate Replace: \L$0
  1. Uppercase all from a lowercase letter within words (e.g. upperCASe => uPPERCASE)
  • Find: (\w)([A-Z]+)
  • Replace: $1\U$2
  1. Uppercase previous (e.g. upperCase => UPPERCase)
  • Find: (\w+)([A-Z])
  • Replace: \U$1$2
  1. Lowercase previous (e.g. LOWERCase => lowerCase)
  • Find: (\w+)([A-Z])
  • Replace: \L$1$2
  1. Uppercase the rest (e.g. upperCase => upperCASE)
  • Find: ([A-Z])(\w+)
  • Replace: $1\U$2
  1. Lowercase the rest (e.g. lOWERCASE => lOwercase)
  • Find: ([A-Z])(\w+)
  • Replace: $1\L$2
  1. Shift-right-uppercase (e.g. Case => cAse => caSe => casE)
  • Find: ([a-z\s])([A-Z])(\w)
  • Replace: $1\l$2\u$3
  1. Shift-left-uppercase (e.g. CasE => CaSe => CAse => Case)
  • Find: (\w)([A-Z])([a-z\s])
  • Replace: \u$1\l$2$3

Show "Open File" Dialog

I have a similar solution to the above and it works for opening, saving, file selecting. I paste it into its own module and use in all the Access DB's I create. As the code states it requires Microsoft Office 14.0 Object Library. Just another option I suppose:

Public Function Select_File(InitPath, ActionType, FileType)
    ' Requires reference to Microsoft Office 14.0 Object Library.

    Dim fDialog As Office.FileDialog
    Dim varFile As Variant


    If ActionType = "FilePicker" Then
        Set fDialog = Application.FileDialog(msoFileDialogFilePicker)
        ' Set up the File Dialog.
    End If
    If ActionType = "SaveAs" Then
        Set fDialog = Application.FileDialog(msoFileDialogSaveAs)
    End If
    If ActionType = "Open" Then
        Set fDialog = Application.FileDialog(msoFileDialogOpen)
    End If
    With fDialog
        .AllowMultiSelect = False
        ' Disallow user to make multiple selections in dialog box
        .Title = "Please specify the file to save/open..."
        ' Set the title of the dialog box.
        If ActionType <> "SaveAs" Then
            .Filters.Clear
            ' Clear out the current filters, and add our own.
            .Filters.Add FileType, "*." & FileType
        End If
        .InitialFileName = InitPath
        ' Show the dialog box. If the .Show method returns True, the
        ' user picked a file. If the .Show method returns
        ' False, the user clicked Cancel.
        If .Show = True Then
        'Loop through each file selected and add it to our list box.
            For Each varFile In .SelectedItems
                'return the subroutine value as the file path & name selected
                Select_File = varFile
            Next
        End If
    End With
End Function

Simplest way to detect a pinch

Unfortunately, detecting pinch gestures across browsers is a not as simple as one would hope, but HammerJS makes it a lot easier!

Check out the Pinch Zoom and Pan with HammerJS demo. This example has been tested on Android, iOS and Windows Phone.

You can find the source code at Pinch Zoom and Pan with HammerJS.

For your convenience, here is the source code:

_x000D_
_x000D_
<!DOCTYPE html>_x000D_
<html>_x000D_
<head>_x000D_
  <meta charset="utf-8">_x000D_
  <meta name="viewport"_x000D_
        content="user-scalable=no, width=device-width, initial-scale=1, maximum-scale=1">_x000D_
  <title>Pinch Zoom</title>_x000D_
</head>_x000D_
_x000D_
<body>_x000D_
_x000D_
  <div>_x000D_
_x000D_
    <div style="height:150px;background-color:#eeeeee">_x000D_
      Ignore this area. Space is needed to test on the iPhone simulator as pinch simulation on the_x000D_
      iPhone simulator requires the target to be near the middle of the screen and we only respect_x000D_
      touch events in the image area. This space is not needed in production._x000D_
    </div>_x000D_
_x000D_
    <style>_x000D_
_x000D_
      .pinch-zoom-container {_x000D_
        overflow: hidden;_x000D_
        height: 300px;_x000D_
      }_x000D_
_x000D_
      .pinch-zoom-image {_x000D_
        width: 100%;_x000D_
      }_x000D_
_x000D_
    </style>_x000D_
_x000D_
    <script src="https://hammerjs.github.io/dist/hammer.js"></script>_x000D_
_x000D_
    <script>_x000D_
_x000D_
      var MIN_SCALE = 1; // 1=scaling when first loaded_x000D_
      var MAX_SCALE = 64;_x000D_
_x000D_
      // HammerJS fires "pinch" and "pan" events that are cumulative in nature and not_x000D_
      // deltas. Therefore, we need to store the "last" values of scale, x and y so that we can_x000D_
      // adjust the UI accordingly. It isn't until the "pinchend" and "panend" events are received_x000D_
      // that we can set the "last" values._x000D_
_x000D_
      // Our "raw" coordinates are not scaled. This allows us to only have to modify our stored_x000D_
      // coordinates when the UI is updated. It also simplifies our calculations as these_x000D_
      // coordinates are without respect to the current scale._x000D_
_x000D_
      var imgWidth = null;_x000D_
      var imgHeight = null;_x000D_
      var viewportWidth = null;_x000D_
      var viewportHeight = null;_x000D_
      var scale = null;_x000D_
      var lastScale = null;_x000D_
      var container = null;_x000D_
      var img = null;_x000D_
      var x = 0;_x000D_
      var lastX = 0;_x000D_
      var y = 0;_x000D_
      var lastY = 0;_x000D_
      var pinchCenter = null;_x000D_
_x000D_
      // We need to disable the following event handlers so that the browser doesn't try to_x000D_
      // automatically handle our image drag gestures._x000D_
      var disableImgEventHandlers = function () {_x000D_
        var events = ['onclick', 'onmousedown', 'onmousemove', 'onmouseout', 'onmouseover',_x000D_
                      'onmouseup', 'ondblclick', 'onfocus', 'onblur'];_x000D_
_x000D_
        events.forEach(function (event) {_x000D_
          img[event] = function () {_x000D_
            return false;_x000D_
          };_x000D_
        });_x000D_
      };_x000D_
_x000D_
      // Traverse the DOM to calculate the absolute position of an element_x000D_
      var absolutePosition = function (el) {_x000D_
        var x = 0,_x000D_
          y = 0;_x000D_
_x000D_
        while (el !== null) {_x000D_
          x += el.offsetLeft;_x000D_
          y += el.offsetTop;_x000D_
          el = el.offsetParent;_x000D_
        }_x000D_
_x000D_
        return { x: x, y: y };_x000D_
      };_x000D_
_x000D_
      var restrictScale = function (scale) {_x000D_
        if (scale < MIN_SCALE) {_x000D_
          scale = MIN_SCALE;_x000D_
        } else if (scale > MAX_SCALE) {_x000D_
          scale = MAX_SCALE;_x000D_
        }_x000D_
        return scale;_x000D_
      };_x000D_
_x000D_
      var restrictRawPos = function (pos, viewportDim, imgDim) {_x000D_
        if (pos < viewportDim/scale - imgDim) { // too far left/up?_x000D_
          pos = viewportDim/scale - imgDim;_x000D_
        } else if (pos > 0) { // too far right/down?_x000D_
          pos = 0;_x000D_
        }_x000D_
        return pos;_x000D_
      };_x000D_
_x000D_
      var updateLastPos = function (deltaX, deltaY) {_x000D_
        lastX = x;_x000D_
        lastY = y;_x000D_
      };_x000D_
_x000D_
      var translate = function (deltaX, deltaY) {_x000D_
        // We restrict to the min of the viewport width/height or current width/height as the_x000D_
        // current width/height may be smaller than the viewport width/height_x000D_
_x000D_
        var newX = restrictRawPos(lastX + deltaX/scale,_x000D_
                                  Math.min(viewportWidth, curWidth), imgWidth);_x000D_
        x = newX;_x000D_
        img.style.marginLeft = Math.ceil(newX*scale) + 'px';_x000D_
_x000D_
        var newY = restrictRawPos(lastY + deltaY/scale,_x000D_
                                  Math.min(viewportHeight, curHeight), imgHeight);_x000D_
        y = newY;_x000D_
        img.style.marginTop = Math.ceil(newY*scale) + 'px';_x000D_
      };_x000D_
_x000D_
      var zoom = function (scaleBy) {_x000D_
        scale = restrictScale(lastScale*scaleBy);_x000D_
_x000D_
        curWidth = imgWidth*scale;_x000D_
        curHeight = imgHeight*scale;_x000D_
_x000D_
        img.style.width = Math.ceil(curWidth) + 'px';_x000D_
        img.style.height = Math.ceil(curHeight) + 'px';_x000D_
_x000D_
        // Adjust margins to make sure that we aren't out of bounds_x000D_
        translate(0, 0);_x000D_
      };_x000D_
_x000D_
      var rawCenter = function (e) {_x000D_
        var pos = absolutePosition(container);_x000D_
_x000D_
        // We need to account for the scroll position_x000D_
        var scrollLeft = window.pageXOffset ? window.pageXOffset : document.body.scrollLeft;_x000D_
        var scrollTop = window.pageYOffset ? window.pageYOffset : document.body.scrollTop;_x000D_
_x000D_
        var zoomX = -x + (e.center.x - pos.x + scrollLeft)/scale;_x000D_
        var zoomY = -y + (e.center.y - pos.y + scrollTop)/scale;_x000D_
_x000D_
        return { x: zoomX, y: zoomY };_x000D_
      };_x000D_
_x000D_
      var updateLastScale = function () {_x000D_
        lastScale = scale;_x000D_
      };_x000D_
_x000D_
      var zoomAround = function (scaleBy, rawZoomX, rawZoomY, doNotUpdateLast) {_x000D_
        // Zoom_x000D_
        zoom(scaleBy);_x000D_
_x000D_
        // New raw center of viewport_x000D_
        var rawCenterX = -x + Math.min(viewportWidth, curWidth)/2/scale;_x000D_
        var rawCenterY = -y + Math.min(viewportHeight, curHeight)/2/scale;_x000D_
_x000D_
        // Delta_x000D_
        var deltaX = (rawCenterX - rawZoomX)*scale;_x000D_
        var deltaY = (rawCenterY - rawZoomY)*scale;_x000D_
_x000D_
        // Translate back to zoom center_x000D_
        translate(deltaX, deltaY);_x000D_
_x000D_
        if (!doNotUpdateLast) {_x000D_
          updateLastScale();_x000D_
          updateLastPos();_x000D_
        }_x000D_
      };_x000D_
_x000D_
      var zoomCenter = function (scaleBy) {_x000D_
        // Center of viewport_x000D_
        var zoomX = -x + Math.min(viewportWidth, curWidth)/2/scale;_x000D_
        var zoomY = -y + Math.min(viewportHeight, curHeight)/2/scale;_x000D_
_x000D_
        zoomAround(scaleBy, zoomX, zoomY);_x000D_
      };_x000D_
_x000D_
      var zoomIn = function () {_x000D_
        zoomCenter(2);_x000D_
      };_x000D_
_x000D_
      var zoomOut = function () {_x000D_
        zoomCenter(1/2);_x000D_
      };_x000D_
_x000D_
      var onLoad = function () {_x000D_
_x000D_
        img = document.getElementById('pinch-zoom-image-id');_x000D_
        container = img.parentElement;_x000D_
_x000D_
        disableImgEventHandlers();_x000D_
_x000D_
        imgWidth = img.width;_x000D_
        imgHeight = img.height;_x000D_
        viewportWidth = img.offsetWidth;_x000D_
        scale = viewportWidth/imgWidth;_x000D_
        lastScale = scale;_x000D_
        viewportHeight = img.parentElement.offsetHeight;_x000D_
        curWidth = imgWidth*scale;_x000D_
        curHeight = imgHeight*scale;_x000D_
_x000D_
        var hammer = new Hammer(container, {_x000D_
          domEvents: true_x000D_
        });_x000D_
_x000D_
        hammer.get('pinch').set({_x000D_
          enable: true_x000D_
        });_x000D_
_x000D_
        hammer.on('pan', function (e) {_x000D_
          translate(e.deltaX, e.deltaY);_x000D_
        });_x000D_
_x000D_
        hammer.on('panend', function (e) {_x000D_
          updateLastPos();_x000D_
        });_x000D_
_x000D_
        hammer.on('pinch', function (e) {_x000D_
_x000D_
          // We only calculate the pinch center on the first pinch event as we want the center to_x000D_
          // stay consistent during the entire pinch_x000D_
          if (pinchCenter === null) {_x000D_
            pinchCenter = rawCenter(e);_x000D_
            var offsetX = pinchCenter.x*scale - (-x*scale + Math.min(viewportWidth, curWidth)/2);_x000D_
            var offsetY = pinchCenter.y*scale - (-y*scale + Math.min(viewportHeight, curHeight)/2);_x000D_
            pinchCenterOffset = { x: offsetX, y: offsetY };_x000D_
          }_x000D_
_x000D_
          // When the user pinch zooms, she/he expects the pinch center to remain in the same_x000D_
          // relative location of the screen. To achieve this, the raw zoom center is calculated by_x000D_
          // first storing the pinch center and the scaled offset to the current center of the_x000D_
          // image. The new scale is then used to calculate the zoom center. This has the effect of_x000D_
          // actually translating the zoom center on each pinch zoom event._x000D_
          var newScale = restrictScale(scale*e.scale);_x000D_
          var zoomX = pinchCenter.x*newScale - pinchCenterOffset.x;_x000D_
          var zoomY = pinchCenter.y*newScale - pinchCenterOffset.y;_x000D_
          var zoomCenter = { x: zoomX/newScale, y: zoomY/newScale };_x000D_
_x000D_
          zoomAround(e.scale, zoomCenter.x, zoomCenter.y, true);_x000D_
        });_x000D_
_x000D_
        hammer.on('pinchend', function (e) {_x000D_
          updateLastScale();_x000D_
          updateLastPos();_x000D_
          pinchCenter = null;_x000D_
        });_x000D_
_x000D_
        hammer.on('doubletap', function (e) {_x000D_
          var c = rawCenter(e);_x000D_
          zoomAround(2, c.x, c.y);_x000D_
        });_x000D_
_x000D_
      };_x000D_
_x000D_
    </script>_x000D_
_x000D_
    <button onclick="zoomIn()">Zoom In</button>_x000D_
    <button onclick="zoomOut()">Zoom Out</button>_x000D_
_x000D_
    <div class="pinch-zoom-container">_x000D_
      <img id="pinch-zoom-image-id" class="pinch-zoom-image" onload="onLoad()"_x000D_
           src="https://hammerjs.github.io/assets/img/pano-1.jpg">_x000D_
    </div>_x000D_
_x000D_
_x000D_
  </div>_x000D_
_x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

How to fetch JSON file in Angular 2

You need to make an HTTP call to your games.json to retrieve it. Something like:

this.http.get(./app/resources/games.json).map

How to avoid "ConcurrentModificationException" while removing elements from `ArrayList` while iterating it?

You have to use the iterator's remove() method, which means no enhanced for loop:

for (final Iterator iterator = myArrayList.iterator(); iterator.hasNext(); ) {
    iterator.next();
    if (someCondition) {
        iterator.remove();
    }
}

Using std::max_element on a vector<double>

min_element and max_element return iterators, not values. So you need *min_element... and *max_element....

Setting default values for columns in JPA

This isn't possible in JPA.

Here's what you can do with the Column annotation: http://java.sun.com/javaee/5/docs/api/javax/persistence/Column.html

Sending mass email using PHP

Also have a look at the PHPmailer class. PHPMailer

Best way to convert string to bytes in Python 3?

If you look at the docs for bytes, it points you to bytearray:

bytearray([source[, encoding[, errors]]])

Return a new array of bytes. The bytearray type is a mutable sequence of integers in the range 0 <= x < 256. It has most of the usual methods of mutable sequences, described in Mutable Sequence Types, as well as most methods that the bytes type has, see Bytes and Byte Array Methods.

The optional source parameter can be used to initialize the array in a few different ways:

If it is a string, you must also give the encoding (and optionally, errors) parameters; bytearray() then converts the string to bytes using str.encode().

If it is an integer, the array will have that size and will be initialized with null bytes.

If it is an object conforming to the buffer interface, a read-only buffer of the object will be used to initialize the bytes array.

If it is an iterable, it must be an iterable of integers in the range 0 <= x < 256, which are used as the initial contents of the array.

Without an argument, an array of size 0 is created.

So bytes can do much more than just encode a string. It's Pythonic that it would allow you to call the constructor with any type of source parameter that makes sense.

For encoding a string, I think that some_string.encode(encoding) is more Pythonic than using the constructor, because it is the most self documenting -- "take this string and encode it with this encoding" is clearer than bytes(some_string, encoding) -- there is no explicit verb when you use the constructor.

Edit: I checked the Python source. If you pass a unicode string to bytes using CPython, it calls PyUnicode_AsEncodedString, which is the implementation of encode; so you're just skipping a level of indirection if you call encode yourself.

Also, see Serdalis' comment -- unicode_string.encode(encoding) is also more Pythonic because its inverse is byte_string.decode(encoding) and symmetry is nice.

Scraping data from website using vba

you can use winhttprequest object instead of internet explorer as it's good to load data excluding pictures n advertisement instead of downloading full webpage including advertisement n pictures those make internet explorer object heavy compare to winhttpRequest object.

Detect whether Office is 32bit or 64bit via the registry

I found this approach:

If HKLM\Software\WOW6432Node exists then Windows is 64-bit.

If HKLM\Software\WOW6432Node\Microsoft\Office exists, then Office is 32-bit.

If HKLM\Software\WOW6432Node\Microsoft\Office does not exist, but HKLM\Software\Microsoft\Office does exist, then Office is 64-bit.

If HKLM\Software\WOW6432Node does not exist, then Windows and Office are 32-bit.

Source: Technet Forums

Web.Config Debug/Release

The web.config transforms that are part of Visual Studio 2010 use XSLT in order to "transform" the current web.config file into its .Debug or .Release version.

In your .Debug/.Release files, you need to add the following parameter in your connection string fields:

xdt:Transform="SetAttributes" xdt:Locator="Match(name)"

This will cause each connection string line to find the matching name and update the attributes accordingly.

Note: You won't have to worry about updating your providerName parameter in the transform files, since they don't change.

Here's an example from one of my apps. Here's the web.config file section:

<connectionStrings>
      <add name="EAF" connectionString="[Test Connection String]" />
</connectionString>

And here's the web.config.release section doing the proper transform:

<connectionStrings>
      <add name="EAF" connectionString="[Prod Connection String]"
           xdt:Transform="SetAttributes"
           xdt:Locator="Match(name)" />
</connectionStrings>

One added note: Transforms only occur when you publish the site, not when you simply run it with F5 or CTRL+F5. If you need to run an update against a given config locally, you will have to manually change your Web.config file for this.

For more details you can see the MSDN documentation

https://msdn.microsoft.com/en-us/library/dd465326(VS.100).aspx

How do I protect Python code?

What about signing your code with standard encryption schemes by hashing and signing important files and checking it with public key methods?

In this way you can issue license file with a public key for each customer.

Additional you can use an python obfuscator like this one (just googled it).

Convert Python program to C/C++ code?

http://code.google.com/p/py2c/ looks like a possibility - they also mention on their site: Cython, Shedskin and RPython and confirm that they are converting Python code to pure C/C++ which is much faster than C/C++ riddled with Python API calls. Note: I haven’t tried it but I am going to..

How to refer to relative paths of resources when working with a code repository

I often use something similar to this:

import os
DATA_DIR = os.path.abspath(os.path.join(os.path.dirname(__file__), 'datadir'))

# if you have more paths to set, you might want to shorten this as
here = lambda x: os.path.abspath(os.path.join(os.path.dirname(__file__), x))
DATA_DIR = here('datadir') 

pathjoin = os.path.join
# ...
# later in script
for fn in os.listdir(DATA_DIR):
    f = open(pathjoin(DATA_DIR, fn))
    # ...

The variable

__file__

holds the file name of the script you write that code in, so you can make paths relative to script, but still written with absolute paths. It works quite well for several reasons:

  • path is absolute, but still relative
  • the project can still be deployed in a relative container

But you need to watch for platform compatibility - Windows' os.pathsep is different than UNIX.

How do I read / convert an InputStream into a String in Java?

String inputStreamToString(InputStream inputStream, Charset charset) throws IOException {
    try (
            final StringWriter writer = new StringWriter();
            final InputStreamReader reader = new InputStreamReader(inputStream, charset)
        ) {
        reader.transferTo(writer);
        return writer.toString();
    }
}

How to run a SQL query on an Excel table?

Microsoft Access and LibreOffice Base can open a spreadsheet as a source and run sql queries on it. That would be the easiest way to run all kinds of queries, and avoid the mess of running macros or writing code.

Excel also has autofilters and data sorting that will accomplish a lot of simple queries like your example. If you need help with those features, Google would be a better source for tutorials than me.

How to drop SQL default constraint without knowing its name?

Run this command to browse all constraints:

exec sp_helpconstraint 'mytable' --and look under constraint_name. 

It will look something like this: DF__Mytable__Column__[ABC123]. Then you can just drop the constraint.

Error retrieving parent for item: No resource found that matches the given name '@android:style/TextAppearance.Holo.Widget.ActionBar.Title'

This happens because in r6 it shows an error when you try to extend private styles.

Refer to this link

Git On Custom SSH Port

(Update: a few years later Google and Qwant "airlines" still send me here when searching for "git non-default ssh port") A probably better way in newer git versions is to use the GIT_SSH_COMMAND ENV.VAR like:

GIT_SSH_COMMAND="ssh -oPort=1234 -i ~/.ssh/myPrivate_rsa.key" \ git clone myuser@myGitRemoteServer:/my/remote/git_repo/path

This has the added advantage of allowing any other ssh suitable option (port, priv.key, IPv6, PKCS#11 device, ...).

nginx error connect to php5-fpm.sock failed (13: Permission denied)

To those who tried everything in this thread and still stuck: This solved my problem. I updated /usr/local/nginx/conf/nginx.conf

  1. Uncomment the line saying user

  2. make it www-data so it becomes: user www-data;

  3. Save it (root access required)

  4. Restart nginx

What is Unicode, UTF-8, UTF-16?

UTF stands for stands for Unicode Transformation Format.Basically in today's world there are scripts written in hundreds of other languages, formats not covered by the basic ASCII used earlier. Hence, UTF came into existence.

UTF-8 has character encoding capabilities and its code unit is 8 bits while that for UTF-16 it is 16 bits.

What is the lifetime of a static variable in a C++ function?

FWIW, Codegear C++Builder doesn't destruct in the expected order according to the standard.

C:\> sample.exe 1 2
Created in foo
Created in if
Destroyed in foo
Destroyed in if

... which is another reason not to rely on the destruction order!

Change bullets color of an HTML list without using span

Try using this instead:

ul {
  color: red;
}

How to check if a variable is set in Bash?

Note

I'm giving a heavily Bash-focused answer because of the bash tag.

Short answer

As long as you're only dealing with named variables in Bash, this function should always tell you if the variable has been set, even if it's an empty array.

variable-is-set() {
    declare -p "$1" &>/dev/null
}

Why this works

In Bash (at least as far back as 3.0), if var is a declared/set variable, then declare -p var outputs a declare command that would set variable var to whatever its current type and value are, and returns status code 0 (success). If var is undeclared, then declare -p var outputs an error message to stderr and returns status code 1. Using &>/dev/null, redirects both regular stdout and stderr output to /dev/null, never to be seen, and without changing the status code. Thus the function only returns the status code.

Why other methods (sometimes) fail in Bash

  • [ -n "$var" ]: This only checks if ${var[0]} is nonempty. (In Bash, $var is the same as ${var[0]}.)
  • [ -n "${var+x}" ]: This only checks if ${var[0]} is set.
  • [ "${#var[@]}" != 0 ]: This only checks if at least one index of $var is set.

When this method fails in Bash

This only works for named variables (including $_), not certain special variables ($!, $@, $#, $$, $*, $?, $-, $0, $1, $2, ..., and any I may have forgotten). Since none of these are arrays, the POSIX-style [ -n "${var+x}" ] works for all of these special variables. But beware of wrapping it in a function since many special variables change values/existence when functions are called.

Shell compatibility note

If your script has arrays and you're trying to make it compatible with as many shells as possible, then consider using typeset -p instead of declare -p. I've read that ksh only supports the former, but haven't been able to test this. I do know that Bash 3.0+ and Zsh 5.5.1 each support both typeset -p and declare -p, differing only in which one is an alternative for the other. But I haven't tested differences beyond those two keywords, and I haven't tested other shells.

If you need your script to be POSIX sh compatible, then you can't use arrays. Without arrays, [ -n "{$var+x}" ] works.

Comparison code for different methods in Bash

This function unsets variable var, evals the passed code, runs tests to determine if var is set by the evald code, and finally shows the resulting status codes for the different tests.

I'm skipping test -v var, [ -v var ], and [[ -v var ]] because they yield identical results to the POSIX standard [ -n "${var+x}" ], while requiring Bash 4.2+. I'm also skipping typeset -p because it's the same as declare -p in the shells I've tested (Bash 3.0 thru 5.0, and Zsh 5.5.1).

is-var-set-after() {
    # Set var by passed expression.
    unset var
    eval "$1"

    # Run the tests, in increasing order of accuracy.
    [ -n "$var" ] # (index 0 of) var is nonempty
    nonempty=$?
    [ -n "${var+x}" ] # (index 0 of) var is set, maybe empty
    plus=$?
    [ "${#var[@]}" != 0 ] # var has at least one index set, maybe empty
    count=$?
    declare -p var &>/dev/null # var has been declared (any type)
    declared=$?

    # Show test results.
    printf '%30s: %2s %2s %2s %2s\n' "$1" $nonempty $plus $count $declared
}

Test case code

Note that test results may be unexpected due to Bash treating non-numeric array indices as "0" if the variable hasn't been declared as an associative array. Also, associative arrays are only valid in Bash 4.0+.

# Header.
printf '%30s: %2s %2s %2s %2s\n' "test" '-n' '+x' '#@' '-p'
# First 5 tests: Equivalent to setting 'var=foo' because index 0 of an
# indexed array is also the nonindexed value, and non-numerical
# indices in an array not declared as associative are the same as
# index 0.
is-var-set-after "var=foo"                        #  0  0  0  0
is-var-set-after "var=(foo)"                      #  0  0  0  0
is-var-set-after "var=([0]=foo)"                  #  0  0  0  0
is-var-set-after "var=([x]=foo)"                  #  0  0  0  0
is-var-set-after "var=([y]=bar [x]=foo)"          #  0  0  0  0
# '[ -n "$var" ]' fails when var is empty.
is-var-set-after "var=''"                         #  1  0  0  0
is-var-set-after "var=([0]='')"                   #  1  0  0  0
# Indices other than 0 are not detected by '[ -n "$var" ]' or by
# '[ -n "${var+x}" ]'.
is-var-set-after "var=([1]='')"                   #  1  1  0  0
is-var-set-after "var=([1]=foo)"                  #  1  1  0  0
is-var-set-after "declare -A var; var=([x]=foo)"  #  1  1  0  0
# Empty arrays are only detected by 'declare -p'.
is-var-set-after "var=()"                         #  1  1  1  0
is-var-set-after "declare -a var"                 #  1  1  1  0
is-var-set-after "declare -A var"                 #  1  1  1  0
# If 'var' is unset, then it even fails the 'declare -p var' test.
is-var-set-after "unset var"                      #  1  1  1  1

Test output

The test mnemonics in the header row correspond to [ -n "$var" ], [ -n "${var+x}" ], [ "${#var[@]}" != 0 ], and declare -p var, respectively.

                         test: -n +x #@ -p
                      var=foo:  0  0  0  0
                    var=(foo):  0  0  0  0
                var=([0]=foo):  0  0  0  0
                var=([x]=foo):  0  0  0  0
        var=([y]=bar [x]=foo):  0  0  0  0
                       var='':  1  0  0  0
                 var=([0]=''):  1  0  0  0
                 var=([1]=''):  1  1  0  0
                var=([1]=foo):  1  1  0  0
declare -A var; var=([x]=foo):  1  1  0  0
                       var=():  1  1  1  0
               declare -a var:  1  1  1  0
               declare -A var:  1  1  1  0
                    unset var:  1  1  1  1

Summary

  • declare -p var &>/dev/null is (100%?) reliable for testing named variables in Bash since at least 3.0.
  • [ -n "${var+x}" ] is reliable in POSIX compliant situations, but cannot handle arrays.
  • Other tests exist for checking if a variable is nonempty, and for checking for declared variables in other shells. But these tests are suited for neither Bash nor POSIX scripts.

Specify system property to Maven project

If your test and webapp are in the same Maven project, you can use a property in the project POM. Then you can filter certain files which will allow Maven to set the property in those files. There are different ways to filter, but the most common is during the resources phase - http://books.sonatype.com/mvnref-book/reference/resource-filtering-sect-description.html

If the test and webapp are in different Maven projects, you can put the property in settings.xml, which is in your maven repository folder (C:\Documents and Settings\username.m2) on Windows. You will still need to use filtering or some other method to read the property into your test and webapp.

HighCharts Hide Series Name from the Legend

Replace return 'Legend' by return ''

Left join only selected columns in R with the merge() function

Nothing elegant but this could be another satisfactory answer.

merge(x = DF1, y = DF2, by = "Client", all.x=TRUE)[,c("Client","LO","CON")]

This will be useful especially when you don't need the keys that were used to join the tables in your results.

How to change Oracle default data pump directory to import dumpfile?

With the directory parameter:

impdp system/password@$ORACLE_SID schemas=USER_SCHEMA directory=MY_DIR \
  dumpfile=mydumpfile.dmp logfile=impdpmydumpfile.log

The default directory is DATA_PUMP_DIR, which is presumably set to /u01/app/oracle/admin/mydatabase/dpdump on your system.

To use a different directory you (or your DBA) will have to create a new directory object in the database, which points to the Oracle-visible operating system directory you put the file into, and assign privileges to the user doing the import.

int to hex string

Previous answer is not good for negative numbers. Use a short type instead of int

        short iValue = -1400;
        string sResult = iValue.ToString("X2");
        Console.WriteLine("Value={0} Result={1}", iValue, sResult);

Now result is FA88

Javascript logical "!==" operator?

Copied from the formal specification: ECMAScript 5.1 section 11.9.5

11.9.4 The Strict Equals Operator ( === )

The production EqualityExpression : EqualityExpression === RelationalExpression is evaluated as follows:

  1. Let lref be the result of evaluating EqualityExpression.
  2. Let lval be GetValue(lref).
  3. Let rref be the result of evaluating RelationalExpression.
  4. Let rval be GetValue(rref).
  5. Return the result of performing the strict equality comparison rval === lval. (See 11.9.6)

11.9.5 The Strict Does-not-equal Operator ( !== )

The production EqualityExpression : EqualityExpression !== RelationalExpression is evaluated as follows:

  1. Let lref be the result of evaluating EqualityExpression.
  2. Let lval be GetValue(lref).
  3. Let rref be the result of evaluating RelationalExpression.
  4. Let rval be GetValue(rref). Let r be the result of performing strict equality comparison rval === lval. (See 11.9.6)
  5. If r is true, return false. Otherwise, return true.

11.9.6 The Strict Equality Comparison Algorithm

The comparison x === y, where x and y are values, produces true or false. Such a comparison is performed as follows:

  1. If Type(x) is different from Type(y), return false.
  2. Type(x) is Undefined, return true.
  3. Type(x) is Null, return true.
  4. Type(x) is Number, then
    1. If x is NaN, return false.
    2. If y is NaN, return false.
    3. If x is the same Number value as y, return true.
    4. If x is +0 and y is -0, return true.
    5. If x is -0 and y is +0, return true.
    6. Return false.
  5. If Type(x) is String, then return true if x and y are exactly the same sequence of characters (same length and same characters in corresponding positions); otherwise, return false.
  6. If Type(x) is Boolean, return true if x and y are both true or both false; otherwise, return false.
  7. Return true if x and y refer to the same object. Otherwise, return false.

jQuery .val change doesn't change input value

<script src="//code.jquery.com/jquery.min.js"></script>
<script>
function changes() {
$('#link').val('new value');
}
</script>
<button onclick="changes()">a</button>
<input type='text' value='http://www.link.com' id='link'>

Concatenating variables and strings in React

exampleData=

        const json1 = [
            {id: 1, test: 1},
            {id: 2, test: 2},
            {id: 3, test: 3},
            {id: 4, test: 4},
            {id: 5, test: 5}
        ];

        const json2 = [
            {id: 3, test: 6},
            {id: 4, test: 7},
            {id: 5, test: 8},
            {id: 6, test: 9},
            {id: 7, test: 10}
        ];

example1=


        const finalData1 = json1.concat(json2).reduce(function (index, obj) {
            index[obj.id] = Object.assign({}, obj, index[obj.id]);
            return index;
        }, []).filter(function (res, obj) {
            return obj;
        });

example2=

        let hashData = new Map();

        json1.concat(json2).forEach(function (obj) {
            hashData.set(obj.id, Object.assign(hashData.get(obj.id) || {}, obj))
        });

        const finalData2 = Array.from(hashData.values());

I recommend second example , it is faster.

Angular - Can't make ng-repeat orderBy work

the built-in orderBy filter will no longer work when iterating an object. It’s ignored due to the way that object fields are stored. You need create a custom filter

yourApp.filter('orderObjectBy', function() {
  return function(items, field, reverse) {
    var filtered = [];
    angular.forEach(items, function(item) {
      filtered.push(item);
    });
    filtered.sort(function (a, b) {
      return (a[field] > b[field] ? 1 : -1);
    });
    if(reverse) filtered.reverse();
    return filtered;
  };
});

<ul>
<li ng-repeat="item in items | orderObjectBy:'color':true">{{ item.color }}</li>
</ul>

How do I convert a datetime to date?

Use the date() method:

datetime.datetime.now().date()

Check if a column contains text using SQL

Try LIKE construction, e.g. (assuming StudentId is of type Char, VarChar etc.)

  select * 
    from Students
   where StudentId like '%' || TEXT || '%' -- <- TEXT - text to contain

How to fit in an image inside span tag?

Try using a div tag and block for span!

<div>
  <span style="padding-right:3px; padding-top: 3px; display:block;">
    <img class="manImg" src="images/ico_mandatory.gif"></img>
  </span>
</div>

Converting double to integer in Java

is there a possibility that casting a double created via Math.round() will still result in a truncated down number

No, round() will always round your double to the correct value, and then, it will be cast to an long which will truncate any decimal places. But after rounding, there will not be any fractional parts remaining.

Here are the docs from Math.round(double):

Returns the closest long to the argument. The result is rounded to an integer by adding 1/2, taking the floor of the result, and casting the result to type long. In other words, the result is equal to the value of the expression:

(long)Math.floor(a + 0.5d)

What is a blob URL and why it is used?

What is blob url? Why it is used?

BLOB is just byte sequence. Browser recognize it as byte stream. It is used to get byte stream from source.

A Blob object represents a file-like object of immutable, raw data. Blobs represent data that isn't necessarily in a JavaScript-native format. The File interface is based on Blob, inheriting blob functionality and expanding it to support files on the user's system.

Can i make my own blob url on a server?

Yes you can there are serveral ways to do so for example try http://php.net/manual/en/function.ibase-blob-echo.php

Read more on

How to "perfectly" override a dict?

How can I make as "perfect" a subclass of dict as possible?

The end goal is to have a simple dict in which the keys are lowercase.

  • If I override __getitem__/__setitem__, then get/set don't work. How do I make them work? Surely I don't need to implement them individually?

  • Am I preventing pickling from working, and do I need to implement __setstate__ etc?

  • Do I need repr, update and __init__?

  • Should I just use mutablemapping (it seems one shouldn't use UserDict or DictMixin)? If so, how? The docs aren't exactly enlightening.

The accepted answer would be my first approach, but since it has some issues, and since no one has addressed the alternative, actually subclassing a dict, I'm going to do that here.

What's wrong with the accepted answer?

This seems like a rather simple request to me:

How can I make as "perfect" a subclass of dict as possible? The end goal is to have a simple dict in which the keys are lowercase.

The accepted answer doesn't actually subclass dict, and a test for this fails:

>>> isinstance(MyTransformedDict([('Test', 'test')]), dict)
False

Ideally, any type-checking code would be testing for the interface we expect, or an abstract base class, but if our data objects are being passed into functions that are testing for dict - and we can't "fix" those functions, this code will fail.

Other quibbles one might make:

  • The accepted answer is also missing the classmethod: fromkeys.
  • The accepted answer also has a redundant __dict__ - therefore taking up more space in memory:

    >>> s.foo = 'bar'
    >>> s.__dict__
    {'foo': 'bar', 'store': {'test': 'test'}}
    

Actually subclassing dict

We can reuse the dict methods through inheritance. All we need to do is create an interface layer that ensures keys are passed into the dict in lowercase form if they are strings.

If I override __getitem__/__setitem__, then get/set don't work. How do I make them work? Surely I don't need to implement them individually?

Well, implementing them each individually is the downside to this approach and the upside to using MutableMapping (see the accepted answer), but it's really not that much more work.

First, let's factor out the difference between Python 2 and 3, create a singleton (_RaiseKeyError) to make sure we know if we actually get an argument to dict.pop, and create a function to ensure our string keys are lowercase:

from itertools import chain
try:              # Python 2
    str_base = basestring
    items = 'iteritems'
except NameError: # Python 3
    str_base = str, bytes, bytearray
    items = 'items'

_RaiseKeyError = object() # singleton for no-default behavior

def ensure_lower(maybe_str):
    """dict keys can be any hashable object - only call lower if str"""
    return maybe_str.lower() if isinstance(maybe_str, str_base) else maybe_str

Now we implement - I'm using super with the full arguments so that this code works for Python 2 and 3:

class LowerDict(dict):  # dicts take a mapping or iterable as their optional first argument
    __slots__ = () # no __dict__ - that would be redundant
    @staticmethod # because this doesn't make sense as a global function.
    def _process_args(mapping=(), **kwargs):
        if hasattr(mapping, items):
            mapping = getattr(mapping, items)()
        return ((ensure_lower(k), v) for k, v in chain(mapping, getattr(kwargs, items)()))
    def __init__(self, mapping=(), **kwargs):
        super(LowerDict, self).__init__(self._process_args(mapping, **kwargs))
    def __getitem__(self, k):
        return super(LowerDict, self).__getitem__(ensure_lower(k))
    def __setitem__(self, k, v):
        return super(LowerDict, self).__setitem__(ensure_lower(k), v)
    def __delitem__(self, k):
        return super(LowerDict, self).__delitem__(ensure_lower(k))
    def get(self, k, default=None):
        return super(LowerDict, self).get(ensure_lower(k), default)
    def setdefault(self, k, default=None):
        return super(LowerDict, self).setdefault(ensure_lower(k), default)
    def pop(self, k, v=_RaiseKeyError):
        if v is _RaiseKeyError:
            return super(LowerDict, self).pop(ensure_lower(k))
        return super(LowerDict, self).pop(ensure_lower(k), v)
    def update(self, mapping=(), **kwargs):
        super(LowerDict, self).update(self._process_args(mapping, **kwargs))
    def __contains__(self, k):
        return super(LowerDict, self).__contains__(ensure_lower(k))
    def copy(self): # don't delegate w/ super - dict.copy() -> dict :(
        return type(self)(self)
    @classmethod
    def fromkeys(cls, keys, v=None):
        return super(LowerDict, cls).fromkeys((ensure_lower(k) for k in keys), v)
    def __repr__(self):
        return '{0}({1})'.format(type(self).__name__, super(LowerDict, self).__repr__())

We use an almost boiler-plate approach for any method or special method that references a key, but otherwise, by inheritance, we get methods: len, clear, items, keys, popitem, and values for free. While this required some careful thought to get right, it is trivial to see that this works.

(Note that haskey was deprecated in Python 2, removed in Python 3.)

Here's some usage:

>>> ld = LowerDict(dict(foo='bar'))
>>> ld['FOO']
'bar'
>>> ld['foo']
'bar'
>>> ld.pop('FoO')
'bar'
>>> ld.setdefault('Foo')
>>> ld
{'foo': None}
>>> ld.get('Bar')
>>> ld.setdefault('Bar')
>>> ld
{'bar': None, 'foo': None}
>>> ld.popitem()
('bar', None)

Am I preventing pickling from working, and do I need to implement __setstate__ etc?

pickling

And the dict subclass pickles just fine:

>>> import pickle
>>> pickle.dumps(ld)
b'\x80\x03c__main__\nLowerDict\nq\x00)\x81q\x01X\x03\x00\x00\x00fooq\x02Ns.'
>>> pickle.loads(pickle.dumps(ld))
{'foo': None}
>>> type(pickle.loads(pickle.dumps(ld)))
<class '__main__.LowerDict'>

__repr__

Do I need repr, update and __init__?

We defined update and __init__, but you have a beautiful __repr__ by default:

>>> ld # without __repr__ defined for the class, we get this
{'foo': None}

However, it's good to write a __repr__ to improve the debugability of your code. The ideal test is eval(repr(obj)) == obj. If it's easy to do for your code, I strongly recommend it:

>>> ld = LowerDict({})
>>> eval(repr(ld)) == ld
True
>>> ld = LowerDict(dict(a=1, b=2, c=3))
>>> eval(repr(ld)) == ld
True

You see, it's exactly what we need to recreate an equivalent object - this is something that might show up in our logs or in backtraces:

>>> ld
LowerDict({'a': 1, 'c': 3, 'b': 2})

Conclusion

Should I just use mutablemapping (it seems one shouldn't use UserDict or DictMixin)? If so, how? The docs aren't exactly enlightening.

Yeah, these are a few more lines of code, but they're intended to be comprehensive. My first inclination would be to use the accepted answer, and if there were issues with it, I'd then look at my answer - as it's a little more complicated, and there's no ABC to help me get my interface right.

Premature optimization is going for greater complexity in search of performance. MutableMapping is simpler - so it gets an immediate edge, all else being equal. Nevertheless, to lay out all the differences, let's compare and contrast.

I should add that there was a push to put a similar dictionary into the collections module, but it was rejected. You should probably just do this instead:

my_dict[transform(key)]

It should be far more easily debugable.

Compare and contrast

There are 6 interface functions implemented with the MutableMapping (which is missing fromkeys) and 11 with the dict subclass. I don't need to implement __iter__ or __len__, but instead I have to implement get, setdefault, pop, update, copy, __contains__, and fromkeys - but these are fairly trivial, since I can use inheritance for most of those implementations.

The MutableMapping implements some things in Python that dict implements in C - so I would expect a dict subclass to be more performant in some cases.

We get a free __eq__ in both approaches - both of which assume equality only if another dict is all lowercase - but again, I think the dict subclass will compare more quickly.

Summary:

  • subclassing MutableMapping is simpler with fewer opportunities for bugs, but slower, takes more memory (see redundant dict), and fails isinstance(x, dict)
  • subclassing dict is faster, uses less memory, and passes isinstance(x, dict), but it has greater complexity to implement.

Which is more perfect? That depends on your definition of perfect.

Select and display only duplicate records in MySQL

This works the fastest for me

SELECT
    primary_key
FROM
    table_name
WHERE
    primary_key NOT IN (
        SELECT
            primary_key
        FROM
            table_name
        GROUP BY
            column_name
        HAVING
            COUNT(*) = 1
    );

SQL Inner join 2 tables with multiple column conditions and update

UPDATE T1,T2 
INNER JOIN T1 ON  T1.Brands = T2.Brands
SET 
T1.Inci = T2.Inci
WHERE
    T1.Category= T2.Category
AND
    T1.Date = T2.Date

printf format specifiers for uint32_t and size_t

If you don't want to use the PRI* macros, another approach for printing ANY integer type is to cast to intmax_t or uintmax_t and use "%jd" or %ju, respectively. This is especially useful for POSIX (or other OS) types that don't have PRI* macros defined, for instance off_t.

Items in JSON object are out of order using "json.dumps"?

hey i know it is so late for this answer but add sort_keys and assign false to it as follows :

json.dumps({'****': ***},sort_keys=False)

this worked for me

Filter array to have unique values

You can use Array.filter function to filter out elements of an array based on the return value of a callback function. The callback function runs for every element of the original array.

The logic for the callback function here is that if the indexOf value for current item is same as the index, it means the element has been encountered first time, so it can be considered unique. If not, it means the element has been encountered already, so should be discarded now.

_x000D_
_x000D_
var arr = ["X_row7", "X_row4", "X_row6", "X_row10", "X_row8", "X_row9", "X_row11", "X_row7", "X_row4", "X_row6", "X_row10", "X_row8", "X_row9", "X_row11", "X_row7", "X_row4", "X_row6", "X_row10", "X_row8", "X_row9", "X_row11", "X_row7", "X_row4", "X_row6", "X_row10", "X_row8", "X_row9", "X_row11", "X_row7", "X_row4", "X_row6", "X_row10", "X_row8", "X_row9", "X_row11", "X_row7", "X_row4", "X_row6", "X_row10", "X_row8", "X_row9", "X_row11"];_x000D_
_x000D_
var filteredArray = arr.filter(function(item, pos){_x000D_
  return arr.indexOf(item)== pos; _x000D_
});_x000D_
_x000D_
console.log( filteredArray );
_x000D_
_x000D_
_x000D_

Caveat: As pointed out by rob in the comments, this method should be avoided with very large arrays as it runs in O(N^2).

UPDATE (16 Nov 2017)

If you can rely on ES6 features, then you can use Set object and Spread operator to create a unique array from a given array, as already specified in @Travis Heeter's answer below:

var uniqueArray = [...new Set(array)]

Map<String, String>, how to print both the "key string" and "value string" together

There are various ways to achieve this. Here are three.

    Map<String, String> map = new HashMap<String, String>();
    map.put("key1", "value1");
    map.put("key2", "value2");
    map.put("key3", "value3");

    System.out.println("using entrySet and toString");
    for (Entry<String, String> entry : map.entrySet()) {
        System.out.println(entry);
    }
    System.out.println();

    System.out.println("using entrySet and manual string creation");
    for (Entry<String, String> entry : map.entrySet()) {
        System.out.println(entry.getKey() + "=" + entry.getValue());
    }
    System.out.println();

    System.out.println("using keySet");
    for (String key : map.keySet()) {
        System.out.println(key + "=" + map.get(key));
    }
    System.out.println();

Output

using entrySet and toString
key1=value1
key2=value2
key3=value3

using entrySet and manual string creation
key1=value1
key2=value2
key3=value3

using keySet
key1=value1
key2=value2
key3=value3

How to enter a series of numbers automatically in Excel

Enter the formula =ROW() into any cell and that cell will show the row number as its value.

If you want 1001, 1002 etc just enter =1000+ROW()

How to return a class object by reference in C++?

You can only return non-local objects by reference. The destructor may have invalidated some internal pointer, or whatever.

Don't be afraid of returning values -- it's fast!

Google Maps API v3: How do I dynamically change the marker icon?

You can try this code

    <script src="http://maps.googleapis.com/maps/api/js"></script>
<script type="text/javascript" src="http://google-maps-utility-library-v3.googlecode.com/svn/trunk/infobox/src/infobox.js"></script>

<script>

    function initialize()
    {
        var map;
        var bounds = new google.maps.LatLngBounds();
        var mapOptions = {
                            zoom: 10,
                            mapTypeId: google.maps.MapTypeId.ROADMAP    
                         };
        map = new google.maps.Map(document.getElementById("mapDiv"), mapOptions);
        var markers = [
            ['title-1', '<img style="width:100%;" src="canberra_hero_image.jpg"></img>', 51.508742, -0.120850, '<p> Hello - 1 </p>'],
            ['title-2', '<img style="width:100%;" src="canberra_hero_image.jpg"></img>', 51.508742, -0.420850, '<p> Hello - 2 </p>'],
            ['title-3', '<img style="width:100%;" src="canberra_hero_image.jpg"></img>', 51.508742, -0.720850, '<p> Hello - 3 </p>'],
            ['title-4', '<img style="width:100%;" src="canberra_hero_image.jpg"></img>', 51.508742, -1.020850, '<p> Hello - 4 </p>'],
            ['title-5', '<img style="width:100%;" src="canberra_hero_image.jpg"></img>', 51.508742, -1.320850, '<p> Hello - 5 </p>']
        ];

        var infoWindow = new google.maps.InfoWindow(), marker, i;
        var testMarker = [];
        var status = [];
        for( i = 0; i < markers.length; i++ ) 
        {
            var title = markers[i][0];
            var loan = markers[i][1];
            var lat = markers[i][2];
            var long = markers[i][3];
            var add = markers[i][4];


            var iconGreen = 'img/greenMarker.png'; //green marker
            var iconRed = 'img/redMarker.png';     //red marker

            var infoWindowContent = loan + "\n" + placeId + add;

            var position = new google.maps.LatLng(lat, long);
            bounds.extend(position);

            marker = new google.maps.Marker({
                map: map,
                title: title,
                position: position,
                icon: iconGreen
            });
            testMarker[i] = marker;
            status[i] = 1;
            google.maps.event.addListener(marker, 'click', ( function toggleBounce( i,status,testMarker) 
            {
                return function() 
                {
                    infoWindow.setContent(markers[i][1]+markers[i][4]);
                    if( status[i] === 1 )
                    {
                        testMarker[i].setIcon(iconRed);
                        status[i] = 0;

                    }
                    for( var k = 0; k <  markers.length ; k++ )
                    {
                        if(k != i)
                        {
                            testMarker[k].setIcon(iconGreen);
                            status[i] = 1;

                        }
                    }
                    infoWindow.open(map, testMarker[i]);
                }
            })( i,status,testMarker));
            map.fitBounds(bounds);
        }
        var boundsListener = google.maps.event.addListener((map), 'bounds_changed', function(event)
        {
            this.setZoom(8);
            google.maps.event.removeListener(boundsListener);
        });
    }
    google.maps.event.addDomListener(window, 'load', initialize);

</script>

<div id="mapDiv" style="width:820px; height:300px"></div>

Where can I find error log files?

What OS you are using and which Webserver? On Linux and Apache you can find the apache error_log in /var/log/apache2/

How to embed fonts in HTML?

Things have changed since this question was originally asked and answered. There's been a large amount of work done on getting cross-browser font embedding for body text to work using @font-face embedding.

Paul Irish put together Bulletproof @font-face syntax combining attempts from multiple other people. If you actually go through the entire article (not just the top) it allows a single @font-face statement to cover IE, Firefox, Safari, Opera, Chrome and possibly others. Basically this can feed out OTF, EOT, SVG and WOFF in ways that don't break anything.

Snipped from his article:

@font-face {
  font-family: 'Graublau Web';
  src: url('GraublauWeb.eot');
  src: local('Graublau Web Regular'), local('Graublau Web'),
    url("GraublauWeb.woff") format("woff"),
    url("GraublauWeb.otf") format("opentype"),
    url("GraublauWeb.svg#grablau") format("svg");
}

Working from that base, Font Squirrel put together a variety of useful tools including the @font-face Generator which allows you to upload a TTF or OTF file and get auto-converted font files for the other types, along with pre-built CSS and a demo HTML page. Font Squirrel also has Hundreds of @font-face kits.

Soma Design also put together the FontFriend Bookmarklet, which redefines fonts on a page on the fly so you can try things out. It includes drag-and-drop @font-face support in FireFox 3.6+.

More recently, Google has started to provide the Google Web Fonts, an assortment of fonts available under an Open Source license and served from Google's servers.

License Restrictions

Finally, WebFonts.info has put together a nice wiki'd list of Fonts available for @font-face embedding based on licenses. It doesn't claim to be an exhaustive list, but fonts on it should be available (possibly with conditions such as an attribution in the CSS file) for embedding/linking. It's important to read the licenses, because there are some limitations that aren't pushed forward obviously on the font downloads.

How to find whether a number belongs to a particular range in Python?

if num in range(min, max):
  """do stuff..."""
else:
  """do other stuff..."""

How do I use disk caching in Picasso?

For caching, I would use OkHttp interceptors to gain control over caching policy. Check out this sample that's included in the OkHttp library.

RewriteResponseCacheControl.java

Here's how I'd use it with Picasso -

OkHttpClient okHttpClient = new OkHttpClient();
    okHttpClient.networkInterceptors().add(new Interceptor() {
        @Override
        public Response intercept(Chain chain) throws IOException {
            Response originalResponse = chain.proceed(chain.request());
            return originalResponse.newBuilder().header("Cache-Control", "max-age=" + (60 * 60 * 24 * 365)).build();
        }
    });

    okHttpClient.setCache(new Cache(mainActivity.getCacheDir(), Integer.MAX_VALUE));
    OkHttpDownloader okHttpDownloader = new OkHttpDownloader(okHttpClient);
    Picasso picasso = new Picasso.Builder(mainActivity).downloader(okHttpDownloader).build();
    picasso.load(imageURL).into(viewHolder.image);

Does Internet Explorer 8 support HTML 5?

IE8's HTML5 support is limited, but Internet Explorer 9 has just been released and has strong support for the new emerging HTML5 technologies.

pandas convert some columns into rows

pd.wide_to_long

You can add a prefix to your year columns and then feed directly to pd.wide_to_long. I won't pretend this is efficient, but it may in certain situations be more convenient than pd.melt, e.g. when your columns already have an appropriate prefix.

df.columns = np.hstack((df.columns[:2], df.columns[2:].map(lambda x: f'Value{x}')))

res = pd.wide_to_long(df, stubnames=['Value'], i='name', j='Date').reset_index()\
        .sort_values(['location', 'name'])

print(res)

   name        Date location  Value
0  test    Jan-2010        A     12
2  test    Feb-2010        A     20
4  test  March-2010        A     30
1   foo    Jan-2010        B     18
3   foo    Feb-2010        B     20
5   foo  March-2010        B     25

Solving Quadratic Equation

one liner solve quadratic equation

from math import sqrt
s = lambda a,b,c: {(-b-sqrt(d))/2*a,(-b+sqrt(d))/2*a} if (d:=b**2-4*a*c)>=0 else {}
roots_set = s(int(input('a=')),int(input('b=')),int(input('c=')))
print(roots_set,f'number of roots {len(roots_set)}')

one line python solve quadratic equations video

How to convert these strange characters? (ë, Ã, ì, ù, Ã)

If you see those characters you probably just didn’t specify the character encoding properly. Because those characters are the result when an UTF-8 multi-byte string is interpreted with a single-byte encoding like ISO 8859-1 or Windows-1252.

In this case ë could be encoded with 0xC3 0xAB that represents the Unicode character ë (U+00EB) in UTF-8.

Meaning of tilde in Linux bash (not home directory)

If you're using autofs then the expansion might actually be coming from /etc/auto.home (or similar for your distro). For example, my /etc/auto.master looks like:

/home2 auto.home --timeout 60

and /etc/auto.home looks like:

mgalgs -rw,noquota,intr space:/space/mgalgs

No connection could be made because the target machine actively refused it 127.0.0.1

If you have this while Fiddler is running -> in Fiddler, go to 'Rules' and disable 'Automatically Authenticate' and it should work again.

Detecting scroll direction

You can try doing this.

_x000D_
_x000D_
function scrollDetect(){_x000D_
  var lastScroll = 0;_x000D_
_x000D_
  window.onscroll = function() {_x000D_
      let currentScroll = document.documentElement.scrollTop || document.body.scrollTop; // Get Current Scroll Value_x000D_
_x000D_
      if (currentScroll > 0 && lastScroll <= currentScroll){_x000D_
        lastScroll = currentScroll;_x000D_
        document.getElementById("scrollLoc").innerHTML = "Scrolling DOWN";_x000D_
      }else{_x000D_
        lastScroll = currentScroll;_x000D_
        document.getElementById("scrollLoc").innerHTML = "Scrolling UP";_x000D_
      }_x000D_
  };_x000D_
}_x000D_
_x000D_
_x000D_
scrollDetect();
_x000D_
html,body{_x000D_
  height:100%;_x000D_
  width:100%;_x000D_
  margin:0;_x000D_
  padding:0;_x000D_
}_x000D_
_x000D_
.cont{_x000D_
  height:100%;_x000D_
  width:100%;_x000D_
}_x000D_
_x000D_
.item{_x000D_
  margin:0;_x000D_
  padding:0;_x000D_
  height:100%;_x000D_
  width:100%;_x000D_
  background: #ffad33;_x000D_
}_x000D_
_x000D_
.red{_x000D_
  background: red;_x000D_
}_x000D_
_x000D_
p{_x000D_
  position:fixed;_x000D_
  font-size:25px;_x000D_
  top:5%;_x000D_
  left:5%;_x000D_
}
_x000D_
<div class="cont">_x000D_
  <div class="item"></div>_x000D_
  <div class="item red"></div>_x000D_
  <p id="scrollLoc">0</p>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Best way to check for IE less than 9 in JavaScript without library

bah to conditional comments! Conditional code all the way!!! (silly IE)

<script type="text/javascript">
/*@cc_on
   var IE_LT_9 = (@_jscript_version < 9);
@*/
</script>

Seriously though, just throwing this out there in case it suits you better... they're the same thing, this can just be in a .js file instead of inline HTML

Note: it is entirely coincidental that the jscript_version check is "9" here. Setting it to 8, 7, etc will NOT check "is IE8", you'd need to lookup the jscript versions for those browsers.

Given two directory trees, how can I find out which files differ by content?

You said Linux, so you luck out (at least it should be available, not sure when it was added):

diff --brief --recursive dir1/ dir2/ # GNU long options
diff -qr dir1/ dir2/ # common short options

Should do what you need.

If you also want to see differences for files that may not exist in either directory:

diff --brief --recursive --new-file dir1/ dir2/ # GNU long options
diff -qrN dir1/ dir2/ # common short options

matplotlib.pyplot will not forget previous plots - how can I flush/refresh?

I would rather use plt.clf() after every plt.show() to just clear the current figure instead of closing and reopening it, keeping the window size and giving you a better performance and much better memory usage.

Similarly, you could do plt.cla() to just clear the current axes.

To clear a specific axes, useful when you have multiple axes within one figure, you could do for example:

fig, axes = plt.subplots(nrows=2, ncols=2)

axes[0, 1].clear()

Converting newline formatting from Mac to Windows

  1. Install dos2unix with homebrew
  2. Run find ./ -type f -exec dos2unix {} \; to recursively convert all line-endings within current folder

How can I find which tables reference a given table in Oracle SQL Developer?

Replace [Your TABLE] with emp in the query below

select owner,constraint_name,constraint_type,table_name,r_owner,r_constraint_name
  from all_constraints 
 where constraint_type='R'
   and r_constraint_name in (select constraint_name 
                               from all_constraints 
                              where constraint_type in ('P','U') 
                                and table_name='[YOUR TABLE]');

How to call any method asynchronously in c#

Here's a way to do it:

// The method to call
void Foo()
{
}


Action action = Foo;
action.BeginInvoke(ar => action.EndInvoke(ar), null);

Of course you need to replace Action by another type of delegate if the method has a different signature

Entity Framework throws exception - Invalid object name 'dbo.BaseCs'

It might me an issue about pluralizing of table names. You can turn off this convention using the snippet below.

 protected override void OnModelCreating(DbModelBuilder modelBuilder)
 {
     base.OnModelCreating(modelBuilder);
     modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
 }

How do I restrict my EditText input to numerical (possibly decimal and signed) input?

use setRawInputType and setKeyListener

editTextNumberPicker.setRawInputType(InputType.TYPE_CLASS_NUMBER | 
                   InputType.TYPE_NUMBER_FLAG_DECIMAL|InputType.TYPE_NUMBER_FLAG_SIGNED );
editTextNumberPicker.setKeyListener(DigitsKeyListener.getInstance(false,true));//set decimals and positive numbers. 

Git: how to reverse-merge a commit?

To revert a merge commit, you need to use: git revert -m <parent number>. So for example, to revert the recent most merge commit using the parent with number 1 you would use:

git revert -m 1 HEAD

To revert a merge commit before the last commit, you would do:

git revert -m 1 HEAD^

Use git show <merge commit SHA1> to see the parents, the numbering is the order they appear e.g. Merge: e4c54b3 4725ad2

git merge documentation: http://schacon.github.com/git/git-merge.html

git merge discussion (confusing but very detailed): http://schacon.github.com/git/howto/revert-a-faulty-merge.txt

Split value from one field to two

The only case where you may want such a function is an UPDATE query which will alter your table to store Firstname and Lastname into separate fields.

Database design must follow certain rules, and Database Normalization is among most important ones

Visual Studio Code Search and Replace with Regular Expressions

So, your goal is to search and replace?
According to the Official Visual Studio's keyboard shotcuts pdf, you can press Ctrl + H on Windows and Linux, or ??F on Mac to enable search and replace tool:

Visual studio code's search & replace tab If you mean to disable the code, you just have to put <h1> in search, and replace to ####.

But if you want to use this regex instead, you may enable it in the icon: .* and use the regex: <h1>(.+?)<\/h1> and replace to: #### $1.

And as @tpartee suggested, here is some more information about Visual Studio's engine if you would like to learn more:

Cannot connect to repo with TortoiseSVN

As stated by David W. "First of all, check your URL" - Our dns entry changed breaking all svn repo connections. Connecting on ip instead of url as Wes stated worked - (now we have to fix our dns)

Run task only if host does not belong to a group

Here's another way to do this:

- name: my command
  command: echo stuff
  when: "'groupname' not in group_names"

group_names is a magic variable as documented here: https://docs.ansible.com/ansible/latest/user_guide/playbooks_variables.html#accessing-information-about-other-hosts-with-magic-variables :

group_names is a list (array) of all the groups the current host is in.

jQuery checkbox check/uncheck

Use .prop() instead and if we go with your code then compare like this:

Look at the example jsbin:

  $("#news_list tr").click(function () {
    var ele = $(this).find(':checkbox');
    if ($(':checked').length) {
      ele.prop('checked', false);
      $(this).removeClass('admin_checked');
    } else {
      ele.prop('checked', true);
      $(this).addClass('admin_checked');
    }
 });

Changes:

  1. Changed input to :checkbox.
  2. Comparing the length of the checked checkboxes.

How to create a horizontal loading progress bar?

Just add a STYLE line and your progress becomes horizontal:

<ProgressBar
        style="?android:attr/progressBarStyleHorizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/progress"
        android:layout_centerHorizontal="true"      
        android:layout_centerVertical="true"      
        android:max="100" 
        android:progress="45"/>

Download a specific tag with Git

$ git clone

will give you the whole repository.

After the clone, you can list the tags with $ git tag -l and then checkout a specific tag:

$ git checkout tags/<tag_name>

Even better, checkout and create a branch (otherwise you will be on a branch named after the revision number of tag):

$ git checkout tags/<tag_name> -b <branch_name>

Python function attributes - uses and abuses

You can do objects the JavaScript way... It makes no sense but it works ;)

>>> def FakeObject():
...   def test():
...     print "foo"
...   FakeObject.test = test
...   return FakeObject
>>> x = FakeObject()
>>> x.test()
foo

Python 3 - ValueError: not enough values to unpack (expected 3, got 2)

You probably want to assign the lastname you are reading out here

lastname = sheet.cell(row=r, column=3).value

to something; currently the program just forgets it

you could do that two lines after, like so

unpaidMembers[name] = lastname, email

your program will still crash at the same place, because .items() still won't give you 3-tuples but rather something that has this structure: (name, (lastname, email))

good news is, python can handle this

for name, (lastname, email) in unpaidMembers.items():

etc.

Read int values from a text file in C

A simple solution using fscanf:

void read_ints (const char* file_name)
{
  FILE* file = fopen (file_name, "r");
  int i = 0;

  fscanf (file, "%d", &i);    
  while (!feof (file))
    {  
      printf ("%d ", i);
      fscanf (file, "%d", &i);      
    }
  fclose (file);        
}

How to remove all subviews of a view in Swift?

One-liner:

while view.subviews.count > 0  { (view.subviews[0] as? NSView)?.removeFromSuperview() } 

CSS flexbox vertically/horizontally center image WITHOUT explicitely defining parent height

Just add the following rules to the parent element:

display: flex;
justify-content: center; /* align horizontal */
align-items: center; /* align vertical */

Here's a sample demo (Resize window to see the image align)

Browser support for Flexbox nowadays is quite good.

For cross-browser compatibility for display: flex and align-items, you can add the older flexbox syntax as well:

display: -webkit-box;
display: -webkit-flex;
display: -moz-box;
display: -ms-flexbox;
display: flex;
-webkit-flex-align: center;
-ms-flex-align: center;
-webkit-align-items: center;
align-items: center;

Format number to always show 2 decimal places

This is how I solve my problem:

parseFloat(parseFloat(floatString).toFixed(2));

How to get HTML 5 input type="date" working in Firefox and/or IE 10

Thank Alexander, I found a way how to modify format for en lang. (Didn't know which lang uses such format)

 $.webshims.formcfg = {
        en: {
            dFormat: '/',
            dateSigns: '/',
            patterns: {
                d: "yy/mm/dd"
            }
        }
     };

 $.webshims.activeLang('en');

What Content-Type value should I send for my XML sitemap?

The difference between text/xml and application/xml is the default character encoding if the charset parameter is omitted:

Text/xml and application/xml behave differently when the charset parameter is not explicitly specified. If the default charset (i.e., US-ASCII) for text/xml is inconvenient for some reason (e.g., bad web servers), application/xml provides an alternative (see "Optional parameters" of application/xml registration in Section 3.2).

For text/xml:

Conformant with [RFC2046], if a text/xml entity is received with the charset parameter omitted, MIME processors and XML processors MUST use the default charset value of "us-ascii"[ASCII]. In cases where the XML MIME entity is transmitted via HTTP, the default charset value is still "us-ascii".

For application/xml:

If an application/xml entity is received where the charset parameter is omitted, no information is being provided about the charset by the MIME Content-Type header. Conforming XML processors MUST follow the requirements in section 4.3.3 of [XML] that directly address this contingency. However, MIME processors that are not XML processors SHOULD NOT assume a default charset if the charset parameter is omitted from an application/xml entity.

So if the charset parameter is omitted, the character encoding of text/xml is US-ASCII while with application/xml the character encoding can be specified in the document itself.

Now a rule of thumb on the internet is: “Be strict with the output but be tolerant with the input.” That means make sure to meet the standards as much as possible when delivering data over the internet. But build in some mechanisms to overlook faults or to guess when receiving and interpreting data over the internet.

So in your case just pick one of the two types (I recommend application/xml) and make sure to specify the used character encoding properly (I recommend to use the respective default character encoding to play safe, so in case of application/xml use UTF-8 or UTF-16).

What is an efficient way to implement a singleton pattern in Java?

I'm mystified by some of the answers that suggest dependency injection (DI) as an alternative to using singletons; these are unrelated concepts. You can use DI to inject either singleton or non-singleton (e.g., per-thread) instances. At least this is true if you use Spring 2.x, I can't speak for other DI frameworks.

So my answer to the OP would be (in all but the most trivial sample code) to:

  1. Use a DI framework like Spring Framework, then
  2. Make it part of your DI configuration whether your dependencies are singletons, request scoped, session scoped, or whatever.

This approach gives you a nice decoupled (and therefore flexible and testable) architecture where whether to use a singleton is an easily reversible implementation detail (provided any singletons you use are threadsafe, of course).

Extracting Nupkg files using command line

This worked for me:

Rename-Item -Path A_Package.nupkg -NewName A_Package.zip

Expand-Archive -Path A_Package.zip -DestinationPath C:\Reference

How to build a Horizontal ListView with RecyclerView?

There is a RecyclerView subclass named HorizontalGridView you can use it to have horizontal direction. VerticalGridView for vertical direction

how to make a new line in a jupyter markdown cell

The double space generally works well. However, sometimes the lacking newline in the PDF still occurs to me when using four pound sign sub titles #### in Jupyter Notebook, as the next paragraph is put into the subtitle as a single paragraph. No amount of double spaces and returns fixed this, until I created a notebook copy 'v. PDF' and started using a single backslash '\' which also indents the next paragraph nicely:

#### 1.1 My Subtitle  \

1.1 My Subtitle
    Next paragraph text.

An alternative to this, is to upgrade the level of your four # titles to three # titles, etc. up the title chain, which will remove the next paragraph indent and format the indent of the title itself (#### My Subtitle ---> ### My Subtitle).

### My Subtitle


1.1 My Subtitle

Next paragraph text.

Select first and last row from grouped data

I know the question specified dplyr. But, since others already posted solutions using other packages, I decided to have a go using other packages too:

Base package:

df <- df[with(df, order(id, stopSequence, stopId)), ]
merge(df[!duplicated(df$id), ], 
      df[!duplicated(df$id, fromLast = TRUE), ], 
      all = TRUE)

data.table:

df <-  setDT(df)
df[order(id, stopSequence)][, .SD[c(1,.N)], by=id]

sqldf:

library(sqldf)
min <- sqldf("SELECT id, stopId, min(stopSequence) AS StopSequence
      FROM df GROUP BY id 
      ORDER BY id, StopSequence, stopId")
max <- sqldf("SELECT id, stopId, max(stopSequence) AS StopSequence
      FROM df GROUP BY id 
      ORDER BY id, StopSequence, stopId")
sqldf("SELECT * FROM min
      UNION
      SELECT * FROM max")

In one query:

sqldf("SELECT * 
        FROM (SELECT id, stopId, min(stopSequence) AS StopSequence
              FROM df GROUP BY id 
              ORDER BY id, StopSequence, stopId)
        UNION
        SELECT *
        FROM (SELECT id, stopId, max(stopSequence) AS StopSequence
              FROM df GROUP BY id 
              ORDER BY id, StopSequence, stopId)")

Output:

  id stopId StopSequence
1  1      a            1
2  1      c            3
3  2      b            1
4  2      c            4
5  3      a            3
6  3      b            1

How to handle back button in activity

This is a simple way of doing something.

    @Override
        public void onBackPressed() {
            // do what you want to do when the "back" button is pressed.
            startActivity(new Intent(Activity.this, MainActivity.class));
            finish();
        }

I think there might be more elaborate ways of going about it, but I like simplicity. For example, I used the template above to make the user sign out of the application AND THEN go back to another activity of my choosing.

Node.js - get raw request body using Express

Edit 2: Release 1.15.2 of the body parser module introduces raw mode, which returns the body as a Buffer. By default, it also automatically handles deflate and gzip decompression. Example usage:

var bodyParser = require('body-parser');
app.use(bodyParser.raw(options));

app.get(path, function(req, res) {
  // req.body is a Buffer object
});

By default, the options object has the following default options:

var options = {
  inflate: true,
  limit: '100kb',
  type: 'application/octet-stream'
};

If you want your raw parser to parse other MIME types other than application/octet-stream, you will need to change it here. It will also support wildcard matching such as */* or */application.


Note: The following answer is for versions before Express 4, where middleware was still bundled with the framework. The modern equivalent is the body-parser module, which must be installed separately.

The rawBody property in Express was once available, but removed since version 1.5.1. To get the raw request body, you have to put in some middleware before using the bodyParser. You can also read a GitHub discussion about it here.

app.use(function(req, res, next) {
  req.rawBody = '';
  req.setEncoding('utf8');

  req.on('data', function(chunk) { 
    req.rawBody += chunk;
  });

  req.on('end', function() {
    next();
  });
});
app.use(express.bodyParser());

That middleware will read from the actual data stream, and store it in the rawBody property of the request. You can then access the raw body like this:

app.post('/', function(req, res) {
  // do something with req.rawBody
  // use req.body for the parsed body
});

Edit: It seems that this method and bodyParser refuse to coexist, because one will consume the request stream before the other, leading to whichever one is second to never fire end, thus never calling next(), and hanging your application.

The simplest solution would most likely be to modify the source of bodyParser, which you would find on line 57 of Connect's JSON parser. This is what the modified version would look like.

var buf = '';
req.setEncoding('utf8');
req.on('data', function(chunk){ buf += chunk });
req.on('end', function() {
  req.rawBody = buf;
  var first = buf.trim()[0];
  ...
});

You would find the file at this location:

/node_modules/express/node_modules/connect/lib/middleware/json.js.

Select Top and Last rows in a table (SQL server)

To get the bottom 1000 you will want to order it by a column in descending order, and still take the top 1000.

SELECT TOP 1000 *
FROM [SomeTable]
ORDER BY MySortColumn DESC

If you care for it to be in the same order as before you can use a common table expression for that:

;WITH CTE AS (
    SELECT TOP 1000 *
    FROM [SomeTable]
    ORDER BY MySortColumn DESC
)

SELECT * 
FROM CTE
ORDER BY MySortColumn

PHPMailer character encoding issues

Sorry for being late on the party. Depending on your server configuration, You may be required to specify character strictly with lowercase letters utf-8, otherwise it will be ignored. Try this if you end up here searching for solutions and none of answers above helps:

$mail->CharSet = "UTF-8";

should be replaced with:

$mail->CharSet = "utf-8";

Unable to copy file - access to the path is denied

I know its an old thread but for those looking for answers, like me a few minutes ago, I recommend trying to restart your computer first. That alone fixed for me. Before could not even manualy copy to the folder.

Send auto email programmatically

Sending email programmatically with Kotlin.

  • simple email sending, not all the other features (like attachments).
  • TLS is always on
  • Only 1 gradle email dependency needed also.

I also found this list of email POP services really helpful:

https://support.office.com/en-gb/article/pop-and-imap-email-settings-for-outlook-8361e398-8af4-4e97-b147-6c6c4ac95353

How to use:

    val auth = EmailService.UserPassAuthenticator("yourUser", "yourPass")
    val to = listOf(InternetAddress("[email protected]"))
    val from = InternetAddress("[email protected]")
    val email = EmailService.Email(auth, to, from, "Test Subject", "Hello Body World")
    val emailService = EmailService("yourSmtpServer", 587)

    GlobalScope.launch { // or however you do background threads
        emailService.send(email)
    }

The code:

import java.util.*
import javax.mail.*
import javax.mail.internet.InternetAddress
import javax.mail.internet.MimeBodyPart
import javax.mail.internet.MimeMessage
import javax.mail.internet.MimeMultipart

class EmailService(private var server: String, private var port: Int) {

    data class Email(
        val auth: Authenticator,
        val toList: List<InternetAddress>,
        val from: Address,
        val subject: String,
        val body: String
    )

    class UserPassAuthenticator(private val username: String, private val password: String) : Authenticator() {
        override fun getPasswordAuthentication(): PasswordAuthentication {
            return PasswordAuthentication(username, password)
        }
    }

    fun send(email: Email) {
        val props = Properties()
        props["mail.smtp.auth"] = "true"
        props["mail.user"] = email.from
        props["mail.smtp.host"] = server
        props["mail.smtp.port"] = port
        props["mail.smtp.starttls.enable"] = "true"
        props["mail.smtp.ssl.trust"] = server
        props["mail.mime.charset"] = "UTF-8"
        val msg: Message = MimeMessage(Session.getDefaultInstance(props, email.auth))
        msg.setFrom(email.from)
        msg.sentDate = Calendar.getInstance().time
        msg.setRecipients(Message.RecipientType.TO, email.toList.toTypedArray())
//      msg.setRecipients(Message.RecipientType.CC, email.ccList.toTypedArray())
//      msg.setRecipients(Message.RecipientType.BCC, email.bccList.toTypedArray())
        msg.replyTo = arrayOf(email.from)

        msg.addHeader("X-Mailer", CLIENT_NAME)
        msg.addHeader("Precedence", "bulk")
        msg.subject = email.subject

        msg.setContent(MimeMultipart().apply {
            addBodyPart(MimeBodyPart().apply {
                setText(email.body, "iso-8859-1")
                //setContent(email.htmlBody, "text/html; charset=UTF-8")
            })
        })
        Transport.send(msg)
    }

    companion object {
        const val CLIENT_NAME = "Android StackOverflow programmatic email"
    }
}

Gradle:

dependencies {
    implementation 'com.sun.mail:android-mail:1.6.4'
    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.3"
}

AndroidManifest:

<uses-permission name="android.permission.INTERNET" />

What's the main difference between Java SE and Java EE?

The biggest difference are the enterprise services (hence the ee) such as an application server supporting EJBs etc.

Javascript ajax call on page onload

This is really easy using a JavaScript library, e.g. using jQuery you could write:

$(document).ready(function(){
$.ajax({ url: "database/update.html",
        context: document.body,
        success: function(){
           alert("done");
        }});
});

Without jQuery, the simplest version might be as follows, but it does not account for browser differences or error handling:

<html>
  <body onload="updateDB();">
  </body>
  <script language="javascript">
    function updateDB() {
      var xhr = new XMLHttpRequest();
      xhr.open("POST", "database/update.html", true);
      xhr.send(null);
      /* ignore result */
    }
  </script>
</html>

See also:

Python os.path.join() on a list

The problem is, os.path.join doesn't take a list as argument, it has to be separate arguments.

This is where *, the 'splat' operator comes into play...

I can do

>>> s = "c:/,home,foo,bar,some.txt".split(",")
>>> os.path.join(*s)
'c:/home\\foo\\bar\\some.txt'

SQL Server stored procedure Nullable parameter

You can/should set your parameter to value to DBNull.Value;

if (variable == "")
{
     cmd.Parameters.Add("@Param", SqlDbType.VarChar, 500).Value = DBNull.Value;
}
else
{
     cmd.Parameters.Add("@Param", SqlDbType.VarChar, 500).Value = variable;
}

Or you can leave your server side set to null and not pass the param at all.

How do I call one constructor from another in Java?

Yes it is possible

public class User {

 private String name = "";
 private String surname = "";
 private int age = 0;
 public User(){
    this("name is undefined","surname is undefined",0);
 }
    public User(String name,String surname){
      this(name,surname,0);
   }


    public User(String name, String surname, int age) {
      this.name = name;
      this.surname = surname;
      this.age = age;
  }
}

Reverse engineering from an APK file to a project

In Android Studio 3.5, It's soo easy that you can just achieve it in a minute. following is a step wise process.

1: Open Android Studio, Press window button -> Type Android Studio -> click on icon to open android studio splash screen which will look like this.

enter image description here

2: Here you can see an option "Profile or debug APK" click on it and select your apk file and press ok.

enter image description here

3: It will open all your manifest and java classes with in a minute depending upon size of apk.

enter image description here

That's it.

WordPress Get the Page ID outside the loop

If you by any means searched this topic because of the post page (index page alternative when using static front page), then the right answer is this:

if (get_option('show_on_front') == 'page') {
    $page_id = get_option('page_for_posts');
    echo get_the_title($page_id);
}

(taken from Forrst | Echo WordPress "Posts Page" title - Some code from tammyhart)

Python & Matplotlib: Make 3D plot interactive in Jupyter Notebook

You may go with Plotly library. It can render interactive 3D plots directly in Jupyter Notebooks.

To do so you first need to install Plotly by running:

pip install plotly

You might also want to upgrade the library by running:

pip install plotly --upgrade

After that in you Jupyter Notebook you may write something like:

# Import dependencies
import plotly
import plotly.graph_objs as go

# Configure Plotly to be rendered inline in the notebook.
plotly.offline.init_notebook_mode()

# Configure the trace.
trace = go.Scatter3d(
    x=[1, 2, 3],  # <-- Put your data instead
    y=[4, 5, 6],  # <-- Put your data instead
    z=[7, 8, 9],  # <-- Put your data instead
    mode='markers',
    marker={
        'size': 10,
        'opacity': 0.8,
    }
)

# Configure the layout.
layout = go.Layout(
    margin={'l': 0, 'r': 0, 'b': 0, 't': 0}
)

data = [trace]

plot_figure = go.Figure(data=data, layout=layout)

# Render the plot.
plotly.offline.iplot(plot_figure)

As a result the following chart will be plotted for you in Jupyter Notebook and you'll be able to interact with it. Of course you will need to provide your specific data instead of suggeseted one.

enter image description here

How do I style a <select> dropdown with only CSS?

Custom Select CSS styles

Tested in Internet Explorer (10 and 11), Edge, Firefox, and Chrome

_x000D_
_x000D_
select::-ms-expand {
  display: none;
}
select {
  display: inline-block;
  box-sizing: border-box;
  padding: 0.5em 2em 0.5em 0.5em;
  border: 1px solid #eee;
  font: inherit;
  line-height: inherit;
  -webkit-appearance: none;
  -moz-appearance: none;
  -ms-appearance: none;
  appearance: none;
  background-repeat: no-repeat;
  background-image: linear-gradient(45deg, transparent 50%, currentColor 50%), linear-gradient(135deg, currentColor 50%, transparent 50%);
  background-position: right 15px top 1em, right 10px top 1em;
  background-size: 5px 5px, 5px 5px;
}
_x000D_
<select name="">
  <option value="">Lorem</option>
  <option value="">Lorem Ipsum</option>
</select>

<select name="" disabled>
  <option value="">Disabled</option>
</select>

<select name="" style="color:red;">
  <option value="">Color!</option>
  <option value="">Lorem Ipsum</option>
</select>
_x000D_
_x000D_
_x000D_

Test if a command outputs an empty string

As Jon Lin commented, ls -al will always output (for . and ..). You want ls -Al to avoid these two directories.

You could for example put the output of the command into a shell variable:

v=$(ls -Al)

An older, non-nestable, notation is

v=`ls -Al`

but I prefer the nestable notation $( ... )

The you can test if that variable is non empty

if [ -n "$v" ]; then
    echo there are files
else
    echo no files
fi

And you could combine both as if [ -n "$(ls -Al)" ]; then

Sometimes, ls may be some shell alias. You might prefer to use $(/bin/ls -Al). See ls(1) and hier(7) and environ(7) and your ~/.bashrc (if your shell is GNU bash; my interactive shell is zsh, defined in /etc/passwd - see passwd(5) and chsh(1)).

How to start a background process in Python?

I found this here:

On windows (win xp), the parent process will not finish until the longtask.py has finished its work. It is not what you want in CGI-script. The problem is not specific to Python, in PHP community the problems are the same.

The solution is to pass DETACHED_PROCESS Process Creation Flag to the underlying CreateProcess function in win API. If you happen to have installed pywin32 you can import the flag from the win32process module, otherwise you should define it yourself:

DETACHED_PROCESS = 0x00000008

pid = subprocess.Popen([sys.executable, "longtask.py"],
                       creationflags=DETACHED_PROCESS).pid

FB OpenGraph og:image not pulling images (possibly https?)

Got here from Google but this wasn't much help for me. It turned out that there is a minimum aspect ratio of 3:1 required for the logo. Mine was almost 4:1. I used Gimp to crop it to exactly 3:1 and voila - my logo is now shown on FB.

How can I send a file document to the printer and have it print?

I know Edwin answered it above but his only prints one document. I use this code to print all files from a given directory.

public void PrintAllFiles()
{
    System.Diagnostics.ProcessStartInfo info = new System.Diagnostics.ProcessStartInfo();
    info.Verb = "print";
    System.Diagnostics.Process p = new System.Diagnostics.Process();
    //Load Files in Selected Folder
    string[] allFiles = System.IO.Directory.GetFiles(Directory);
    foreach (string file in allFiles)
    {
        info.FileName = @file;
        info.CreateNoWindow = true;
        info.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
         p.StartInfo = info;
        p.Start();
    }
    //p.Kill(); Can Create A Kill Statement Here... but I found I don't need one
    MessageBox.Show("Print Complete");
}

It essentually cycles through each file in the given directory variable Directory - > for me it was @"C:\Users\Owner\Documents\SalesVaultTesting\" and prints off those files to your default printer.

Is it possible in Java to catch two exceptions in the same catch block?

Java <= 6.x just allows you to catch one exception for each catch block:

try {

} catch (ExceptionType name) {

} catch (ExceptionType name) {

}

Documentation:

Each catch block is an exception handler and handles the type of exception indicated by its argument. The argument type, ExceptionType, declares the type of exception that the handler can handle and must be the name of a class that inherits from the Throwable class.

For Java 7 you can have multiple Exception caught on one catch block:

catch (IOException|SQLException ex) {
    logger.log(ex);
    throw ex;
}

Documentation:

In Java SE 7 and later, a single catch block can handle more than one type of exception. This feature can reduce code duplication and lessen the temptation to catch an overly broad exception.

Reference: http://docs.oracle.com/javase/tutorial/essential/exceptions/catch.html

What ports need to be open for TortoiseSVN to authenticate (clear text) and commit?

What's the first part of your Subversion repository URL?

  • If your URL looks like: http://subversion/repos/, then you're probably going over Port 80.
  • If your URL looks like: https://subversion/repos/, then you're probably going over Port 443.
  • If your URL looks like: svn://subversion/, then you're probably going over Port 3690.
  • If your URL looks like: svn+ssh://subversion/repos/, then you're probably going over Port 22.
  • If your URL contains a port number like: http://subversion/repos:8080, then you're using that port.

I can't guarantee the first four since it's possible to reconfigure everything to use different ports, of if you go through a proxy of some sort.

If you're using a VPN, you may have to configure your VPN client to reroute these to their correct ports. A lot of places don't configure their correctly VPNs to do this type of proxying. It's either because they have some sort of anal-retentive IT person who's being overly security conscious, or because they simply don't know any better. Even worse, they'll give you a client where this stuff can't be reconfigured.

The only way around that is to log into a local machine over the VPN, and then do everything from that system.

How to dynamically create columns in datatable and assign values to it?

If you want to create dynamically/runtime data table in VB.Net then you should follow these steps as mentioned below :

  • Create Data table object.
  • Add columns into that data table object.
  • Add Rows with values into the object.

For eg.

Dim dt As New DataTable

dt.Columns.Add("Id", GetType(Integer))
dt.Columns.Add("FirstName", GetType(String))
dt.Columns.Add("LastName", GetType(String))

dt.Rows.Add(1, "Test", "data")
dt.Rows.Add(15, "Robert", "Wich")
dt.Rows.Add(18, "Merry", "Cylon")
dt.Rows.Add(30, "Tim", "Burst")

Parsing a JSON array using Json.Net

Use Manatee.Json https://github.com/gregsdennis/Manatee.Json/wiki/Usage

And you can convert the entire object to a string, filename.json is expected to be located in documents folder.

        var text = File.ReadAllText("filename.json");
        var json = JsonValue.Parse(text);

        while (JsonValue.Null != null)
        {
            Console.WriteLine(json.ToString());

        }
        Console.ReadLine();

Redirect within component Angular 2

@kit's answer is okay, but remember to add ROUTER_PROVIDERS to providers in the component. Then you can redirect to another page within ngOnInit method:

import {Component, OnInit} from 'angular2/core';
import {Router, ROUTER_PROVIDERS} from 'angular2/router'

@Component({
    selector: 'loginForm',
    templateUrl: 'login.html',
    providers: [ROUTER_PROVIDERS]
})

export class LoginComponent implements OnInit {

    constructor(private router: Router) { }

    ngOnInit() {
        this.router.navigate(['./SomewhereElse']);
    }

}

Select distinct values from a table field

Say your model is 'Shop'

class Shop(models.Model):
    street = models.CharField(max_length=150)
    city = models.CharField(max_length=150)

    # some of your models may have explicit ordering
    class Meta:
        ordering = ('city')

Since you may have the Meta class ordering attribute set, you can use order_by() without parameters to clear any ordering when using distinct(). See the documentation under order_by()

If you don’t want any ordering to be applied to a query, not even the default ordering, call order_by() with no parameters.

and distinct() in the note where it discusses issues with using distinct() with ordering.

To query your DB, you just have to call:

models.Shop.objects.order_by().values('city').distinct()

It returns a dictionnary

or

models.Shop.objects.order_by().values_list('city').distinct()

This one returns a ValuesListQuerySet which you can cast to a list. You can also add flat=True to values_list to flatten the results.

See also: Get distinct values of Queryset by field

How do I find out what is hammering my SQL Server?

Run either of these a few second apart. You'll detect the high CPU connection. Or: stored CPU in a local variable, WAITFOR DELAY, compare stored and current CPU values

select * from master..sysprocesses
where status = 'runnable' --comment this out
order by CPU
desc

select * from master..sysprocesses
order by CPU
desc

May not be the most elegant but it'd effective and quick.

long long int vs. long int vs. int64_t in C++

You don't need to go to 64-bit to see something like this. Consider int32_t on common 32-bit platforms. It might be typedef'ed as int or as a long, but obviously only one of the two at a time. int and long are of course distinct types.

It's not hard to see that there is no workaround which makes int == int32_t == long on 32-bit systems. For the same reason, there's no way to make long == int64_t == long long on 64-bit systems.

If you could, the possible consequences would be rather painful for code that overloaded foo(int), foo(long) and foo(long long) - suddenly they'd have two definitions for the same overload?!

The correct solution is that your template code usually should not be relying on a precise type, but on the properties of that type. The whole same_type logic could still be OK for specific cases:

long foo(long x);
std::tr1::disable_if(same_type(int64_t, long), int64_t)::type foo(int64_t);

I.e., the overload foo(int64_t) is not defined when it's exactly the same as foo(long).

[edit] With C++11, we now have a standard way to write this:

long foo(long x);
std::enable_if<!std::is_same<int64_t, long>::value, int64_t>::type foo(int64_t);

[edit] Or C++20

long foo(long x);
int64_t foo(int64_t) requires (!std::is_same_v<int64_t, long>);

Start an Activity with a parameter

Put an int which is your id into the new Intent.

Intent intent = new Intent(FirstActivity.this, SecondActivity.class);
Bundle b = new Bundle();
b.putInt("key", 1); //Your id
intent.putExtras(b); //Put your id to your next Intent
startActivity(intent);
finish();

Then grab the id in your new Activity:

Bundle b = getIntent().getExtras();
int value = -1; // or other values
if(b != null)
    value = b.getInt("key");

When to use a View instead of a Table?

First of all as the name suggests a view is immutable. thats because a view is nothing other than a virtual table created from a stored query in the DB. Because of this you have some characteristics of views:

  • you can show only a subset of the data
  • you can join multiple tables into a single view
  • you can aggregate data in a view (select count)
  • view dont actually hold data, they dont need any tablespace since they are virtual aggregations of underlying tables

so there are a gazillion of use cases for which views are better fitted than tables, just think about only displaying active users on a website. a view would be better because you operate only on a subset of the data which actually is in your DB (active and inactive users)

check out this article

hope this helped..

Bash script to run php script

You just need to set :

/usr/bin/php path_to_your_php_file

in your crontab.

Using find to locate files that match one of multiple patterns

My default has been:

find -type f | egrep -i "*.java|*.css|*.cs|*.sql"

Like the less process intencive find execution by Brendan Long and Stephan202 et al.:

find Documents \( -name "*.py" -or -name "*.html" \)

How to split csv whose columns may contain ,

Use the Microsoft.VisualBasic.FileIO.TextFieldParser class. This will handle parsing a delimited file, TextReader or Stream where some fields are enclosed in quotes and some are not.

For example:

using Microsoft.VisualBasic.FileIO;

string csv = "2,1016,7/31/2008 14:22,Geoff Dalgas,6/5/2011 22:21,http://stackoverflow.com,\"Corvallis, OR\",7679,351,81,b437f461b3fd27387c5d8ab47a293d35,34";

TextFieldParser parser = new TextFieldParser(new StringReader(csv));

// You can also read from a file
// TextFieldParser parser = new TextFieldParser("mycsvfile.csv");

parser.HasFieldsEnclosedInQuotes = true;
parser.SetDelimiters(",");

string[] fields;

while (!parser.EndOfData)
{
    fields = parser.ReadFields();
    foreach (string field in fields)
    {
        Console.WriteLine(field);
    }
} 

parser.Close();

This should result in the following output:

2
1016
7/31/2008 14:22
Geoff Dalgas
6/5/2011 22:21
http://stackoverflow.com
Corvallis, OR
7679
351
81
b437f461b3fd27387c5d8ab47a293d35
34

See Microsoft.VisualBasic.FileIO.TextFieldParser for more information.

You need to add a reference to Microsoft.VisualBasic in the Add References .NET tab.

Force GUI update from UI Thread

I had the same problem with property Enabled and I discovered a first chance exception raised because of it is not thread-safe. I found solution about "How to update the GUI from another thread in C#?" here https://stackoverflow.com/a/661706/1529139 And it works !

Generate GUID in MySQL for existing Data?

Just a minor addition to make as I ended up with a weird result when trying to modify the UUIDs as they were generated. I found the answer by Rakesh to be the simplest that worked well, except in cases where you want to strip the dashes.

For reference:

UPDATE some_table SET some_field=(SELECT uuid());

This worked perfectly on its own. But when I tried this:

UPDATE some_table SET some_field=(REPLACE((SELECT uuid()), '-', ''));

Then all the resulting values were the same (not subtly different - I quadruple checked with a GROUP BY some_field query). Doesn't matter how I situated the parentheses, the same thing happens.

UPDATE some_table SET some_field=(REPLACE(SELECT uuid(), '-', ''));

It seems when surrounding the subquery to generate a UUID with REPLACE, it only runs the UUID query once, which probably makes perfect sense as an optimization to much smarter developers than I, but it didn't to me.

To resolve this, I just split it into two queries:

UPDATE some_table SET some_field=(SELECT uuid());
UPDATE some_table SET some_field=REPLACE(some_field, '-', '');

Simple solution, obviously, but hopefully this will save someone the time that I just lost.

Redirecting to a relative URL in JavaScript

<a href="..">no JS needed</a>

.. means parent directory.

c++ array assignment of multiple values

There is a difference between initialization and assignment. What you want to do is not initialization, but assignment. But such assignment to array is not possible in C++.

Here is what you can do:

#include <algorithm>

int array [] = {1,3,34,5,6};
int newarr [] = {34,2,4,5,6};
std::copy(newarr, newarr + 5, array);

However, in C++0x, you can do this:

std::vector<int> array = {1,3,34,5,6};
array = {34,2,4,5,6};

Of course, if you choose to use std::vector instead of raw array.

org.json.simple.JSONArray cannot be cast to org.json.simple.JSONObject

JSONObject site = (JSONObject)jsonSites.get(i); // Exception happens here.

The return type of jsonSites.get(i) is JSONArray not JSONObject. Because sites have two '[', two means there are two arrays here.

How to Uninstall RVM?

It’s easy; just do the following:

rvm implode

or

rm -rf ~/.rvm

And don’t forget to remove the script calls in the following files:

  • ~/.bashrc
  • ~/.bash_profile
  • ~/.profile

And maybe others depending on whatever shell you’re using.

Number of days in particular month of particular year?

In Java8 you can use get ValueRange from a field of a date.

LocalDateTime dateTime = LocalDateTime.now();

ChronoField chronoField = ChronoField.MONTH_OF_YEAR;
long max = dateTime.range(chronoField).getMaximum();

This allows you to parameterize on the field.

ArrayList vs List<> in C#

Yes, pretty much. List<T> is a generic class. It supports storing values of a specific type without casting to or from object (which would have incurred boxing/unboxing overhead when T is a value type in the ArrayList case). ArrayList simply stores object references. As a generic collection, List<T> implements the generic IEnumerable<T> interface and can be used easily in LINQ (without requiring any Cast or OfType call).

ArrayList belongs to the days that C# didn't have generics. It's deprecated in favor of List<T>. You shouldn't use ArrayList in new code that targets .NET >= 2.0 unless you have to interface with an old API that uses it.

How to refresh the data in a jqGrid?

$('#grid').trigger( 'reloadGrid' );

Seeding the random number generator in Javascript

In PHP, there is function srand(seed) which generate fixed random value for particular seed. But, in JS, there is no such inbuilt function.

However, we can write simple and short function.

Step 1: Choose some Seed (Fix Number).
var seed = 100;
Number should be Positive Integer and greater than 1, further explanation in Step 2.

Step 2: Perform Math.sin() function on Seed, it will give sin value of that number. Store this value in variable x.

var x; 
x = Math.sin(seed); // Will Return Fractional Value between -1 & 1 (ex. 0.4059..)

sin() method returns a Fractional value between -1 and 1.
And we don't need Negative value, therefore, in first step choose number greater than 1.

Step 3: Returned Value is a Fractional value between -1 and 1.
So mulitply this value with 10 for making it more than 1.

x = x * 10; // 10 for Single Digit Number

Step 4: Multiply the value with 10 for additional digits

x = x * 10; // Will Give value between 10 and 99 OR
x = x * 100; // Will Give value between 100 and 999

Multiply as per requirement of digits.

The result will be in decimal.

Step 5: Remove value after Decimal Point by Math's Round (Math.round()) Method.

x = Math.round(x); // This will give Integer Value.

Step 6: Turn Negative Values into Positive (if any) by Math.abs method

x = Math.abs(x); // Convert Negative Values into Positive(if any)

Explanation End.

Final Code

var seed = 111; // Any Number greater than 1
var digit = 10 // 1 => single digit, 10 => 2 Digits, 100 => 3 Digits and so. (Multiple of 10) 

var x; // Initialize the Value to store the result
x = Math.sin(seed); // Perform Mathematical Sin Method on Seed.
x = x * 10; // Convert that number into integer
x = x * digit; // Number of Digits to be included
x = Math.round(x); // Remove Decimals
x = Math.abs(x); // Convert Negative Number into Positive

Clean and Optimized Functional Code

function random_seed(seed, digit = 1) {
    var x = Math.abs(Math.round(Math.sin(seed++) * 10 * digit));
    return x;
}

Then Call this function using
random_seed(any_number, number_of_digits)
any_number is must and should be greater than 1.
number_of_digits is optional parameter and if nothing passed, 1 Digit will return.

random_seed(555); // 1 Digit
random_seed(234, 1); // 1 Digit
random_seed(7895656, 1000); // 4 Digit

MySQL with Node.js

Imo, you should try MySQL Connector/Node.js which is the official Node.js driver for MySQL. See ref-1 and ref-2 for detailed explanation. I have tried mysqljs/mysql which is available here, but I don't find detailed documentation on classes, methods, properties of this library.

So I switched to the standard MySQL Connector/Node.js with X DevAPI, since it is an asynchronous Promise-based client library and provides good documentation. Take a look at the following code snippet :

const mysqlx = require('@mysql/xdevapi');
const rows = [];

mysqlx.getSession('mysqlx://localhost:33060')
.then(session => {
    const table = session.getSchema('testSchema').getTable('testTable');

    // The criteria is defined through the expression.
    return table.update().where('name = "bar"').set('age', 50)
        .execute()
        .then(() => {
            return table.select().orderBy('name ASC')
                .execute(row => rows.push(row));
        });
})
.then(() => {
    console.log(rows);
});

How to source virtualenv activate in a Bash script

You should use multiple commands in one line. for example:

os.system(". Projects/virenv/bin/activate && python Projects/virenv/django-project/manage.py runserver")

when you activate your virtual environment in one line, I think it forgets for other command lines and you can prevent this by using multiple commands in one line. It worked for me :)