Programs & Examples On #Filesort

When MySQL needs to sort its output rows, and cannot do this via indexes, it uses a quicksort function called filesort(). This does not necessarily mean it will touch the disk at any time. If small enough, the sort can be performed in memory.

Postgresql Windows, is there a default password?

Try this:

Open PgAdmin -> Files -> Open pgpass.conf

You would get the path of pgpass.conf at the bottom of the window. Go to that location and open this file, you can find your password there.

Reference

If the above does not work, you may consider trying this:

 1. edit pg_hba.conf to allow trust authorization temporarily
 2. Reload the config file (pg_ctl reload)
 3. Connect and issue ALTER ROLE / PASSWORD to set the new password
 4. edit pg_hba.conf again and restore the previous settings
 5. Reload the config file again

Cloning an Object in Node.js

var obj2 = JSON.parse(JSON.stringify(obj1));

Get number days in a specified month using JavaScript?

Date.prototype.monthDays= function(){
    var d= new Date(this.getFullYear(), this.getMonth()+1, 0);
    return d.getDate();
}

Differences between time complexity and space complexity?

There is a well know relation between time and space complexity.

First of all, time is an obvious bound to space consumption: in time t you cannot reach more than O(t) memory cells. This is usually expressed by the inclusion

                            DTime(f) ? DSpace(f)

where DTime(f) and DSpace(f) are the set of languages recognizable by a deterministic Turing machine in time (respectively, space) O(f). That is to say that if a problem can be solved in time O(f), then it can also be solved in space O(f).

Less evident is the fact that space provides a bound to time. Suppose that, on an input of size n, you have at your disposal f(n) memory cells, comprising registers, caches and everything. After having written these cells in all possible ways you may eventually stop your computation, since otherwise you would reenter a configuration you already went through, starting to loop. Now, on a binary alphabet, f(n) cells can be written in 2^f(n) different ways, that gives our time upper bound: either the computation will stop within this bound, or you may force termination, since the computation will never stop.

This is usually expressed in the inclusion

                          DSpace(f) ? Dtime(2^(cf))

for some constant c. the reason of the constant c is that if L is in DSpace(f) you only know that it will be recognized in Space O(f), while in the previous reasoning, f was an actual bound.

The above relations are subsumed by stronger versions, involving nondeterministic models of computation, that is the way they are frequently stated in textbooks (see e.g. Theorem 7.4 in Computational Complexity by Papadimitriou).

Error TF30063: You are not authorized to access ... \DefaultCollection

For me the error came after changing my password for my AD account.

I had to remove the line from credential manager (which contained the previous password.)

Then it worked again.

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

Answer

You can't according to the PHP manual:

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

This is because cookies are sent in response headers to the browser and the browser must then send them back with the next request. This is why they are only available on the second page load.

Work around

But you can work around it by also setting $_COOKIE when you call setcookie():

if(!isset($_COOKIE['lg'])) {
    setcookie('lg', 'ro');
    $_COOKIE['lg'] = 'ro';
}
echo $_COOKIE['lg'];

make UITableViewCell selectable only while editing

Have you tried setting the selection properties of your tableView like this:

tableView.allowsMultipleSelection = NO; tableView.allowsMultipleSelectionDuringEditing = YES; tableView.allowsSelection = NO; tableView.allowsSelectionDuringEditing YES; 

If you want more fine-grain control over when selection is allowed you can override - (NSIndexPath *)tableView:(UITableView *)tableView willSelectRowAtIndexPath:(NSIndexPath *)indexPath in your UITableView delegate. The documentation states:

Return Value An index-path object that confirms or alters the selected row. Return an NSIndexPath object other than indexPath if you want another cell to be selected. Return nil if you don't want the row selected. 

You can have this method return nil in cases where you don't want the selection to happen.

How to use workbook.saveas with automatic Overwrite

To split the difference of opinion

I prefer:

   xls.DisplayAlerts = False    
   wb.SaveAs fullFilePath, AccessMode:=xlExclusive, ConflictResolution:=xlLocalSessionChanges
   xls.DisplayAlerts = True

Foreign Key naming scheme

Based on the answers and comments here, a naming convention which includes the FK table, FK field, and PK table (FK_FKTbl_FKCol_PKTbl) should avoid FK constraint name collisions.

So, for the given tables here:

fk_task_userid_user
fk_note_userid_user

So, if you add a column to track who last modified a task or a note...

fk_task_modifiedby_user
fk_note_modifiedby_user

Setting a max character length in CSS

That's not possible with CSS, you will have to use the Javascript for that. Although you can set the width of the p to as much as 30 characters and next letters will automatically come down but again this won't be that accurate and will vary if the characters are in capital.

VHDL - How should I create a clock in a testbench?

If multiple clock are generated with different frequencies, then clock generation can be simplified if a procedure is called as concurrent procedure call. The time resolution issue, mentioned by Martin Thompson, may be mitigated a little by using different high and low time in the procedure. The test bench with procedure for clock generation is:

library ieee;
use ieee.std_logic_1164.all;

entity tb is
end entity;

architecture sim of tb is

  -- Procedure for clock generation
  procedure clk_gen(signal clk : out std_logic; constant FREQ : real) is
    constant PERIOD    : time := 1 sec / FREQ;        -- Full period
    constant HIGH_TIME : time := PERIOD / 2;          -- High time
    constant LOW_TIME  : time := PERIOD - HIGH_TIME;  -- Low time; always >= HIGH_TIME
  begin
    -- Check the arguments
    assert (HIGH_TIME /= 0 fs) report "clk_plain: High time is zero; time resolution to large for frequency" severity FAILURE;
    -- Generate a clock cycle
    loop
      clk <= '1';
      wait for HIGH_TIME;
      clk <= '0';
      wait for LOW_TIME;
    end loop;
  end procedure;

  -- Clock frequency and signal
  signal clk_166 : std_logic;
  signal clk_125 : std_logic;

begin

  -- Clock generation with concurrent procedure call
  clk_gen(clk_166, 166.667E6);  -- 166.667 MHz clock
  clk_gen(clk_125, 125.000E6);  -- 125.000 MHz clock

  -- Time resolution show
  assert FALSE report "Time resolution: " & time'image(time'succ(0 fs)) severity NOTE;

end architecture;

The time resolution is printed on the terminal for information, using the concurrent assert last in the test bench.

If the clk_gen procedure is placed in a separate package, then reuse from test bench to test bench becomes straight forward.

Waveform for clocks are shown in figure below.

Waveforms for clk_166 and clk_125

An more advanced clock generator can also be created in the procedure, which can adjust the period over time to match the requested frequency despite the limitation by time resolution. This is shown here:

-- Advanced procedure for clock generation, with period adjust to match frequency over time, and run control by signal
procedure clk_gen(signal clk : out std_logic; constant FREQ : real; PHASE : time := 0 fs; signal run : std_logic) is
  constant HIGH_TIME   : time := 0.5 sec / FREQ;  -- High time as fixed value
  variable low_time_v  : time;                    -- Low time calculated per cycle; always >= HIGH_TIME
  variable cycles_v    : real := 0.0;             -- Number of cycles
  variable freq_time_v : time := 0 fs;            -- Time used for generation of cycles
begin
  -- Check the arguments
  assert (HIGH_TIME /= 0 fs) report "clk_gen: High time is zero; time resolution to large for frequency" severity FAILURE;
  -- Initial phase shift
  clk <= '0';
  wait for PHASE;
  -- Generate cycles
  loop
    -- Only high pulse if run is '1' or 'H'
    if (run = '1') or (run = 'H') then
      clk <= run;
    end if;
    wait for HIGH_TIME;
    -- Low part of cycle
    clk <= '0';
    low_time_v := 1 sec * ((cycles_v + 1.0) / FREQ) - freq_time_v - HIGH_TIME;  -- + 1.0 for cycle after current
    wait for low_time_v;
    -- Cycle counter and time passed update
    cycles_v := cycles_v + 1.0;
    freq_time_v := freq_time_v + HIGH_TIME + low_time_v;
  end loop;
end procedure;

Again reuse through a package will be nice.

How do I check if a Key is pressed on C++

check if a key is pressed, if yes, then do stuff

Consider 'select()', if this (reportedly Posix) function is available on your os.

'select()' uses 3 sets of bits, which you create using functions provided (see man select, FD_SET, etc). You probably only need create the input bits (for now)


from man page:

'select()' "allow a program to monitor multiple file descriptors, waiting until one or more of the file descriptors become "ready" for some class of I/O operation (e.g., input possible). A file descriptor is considered ready if it is possible to perform a corresponding I/O operation (e.g., read(2) without blocking...)"

When select is invoked:

a) the function looks at each fd identified in the sets, and if that fd state indicates you can do something (perhaps read, perhaps write), select will return and let you go do that ... 'all you got to do' is scan the bits, find the set bit, and take action on the fd associated with that bit.

The 1st set (passed into select) contains active input fd's (typically devices). Probably 1 bit in this set is all you will need. And with only 1 fd (i.e. an input from keyboard), 1 bit, this is all quite simple. With this return from select, you can 'do-stuff' (perhaps, after you have fetched the char).

b) the function also has a timeout, with which you identify how much time to await a change of the fd state. If the fd state does not change, the timeout will cause 'select()' to return with a 0. (i.e. no keyboard input) Your code can do something at this time, too, perhaps an output.

fyi - fd's are typically 0,1,2... Remembe that C uses 0 as STDIN, 1 and STDOUT.


Simple test set up: I open a terminal (separate from my console), and type the tty command in that terminal to find its id. The response is typically something like "/dev/pts/0", or 3, or 17...

Then I get an fd to use in 'select()' by using open:

// flag options are: O_RDONLY, O_WRONLY, or O_RDWR
int inFD = open( "/dev/pts/5", O_RDONLY ); 

It is useful to cout this value.

Here is a snippet to consider (from man select):

  fd_set rfds;
  struct timeval tv;
  int retval;

  /* Watch stdin (fd 0) to see when it has input. */
  FD_ZERO(&rfds);
  FD_SET(0, &rfds);

  /* Wait up to five seconds. */
  tv.tv_sec = 5;
  tv.tv_usec = 0;

  retval = select(1, &rfds, NULL, NULL, &tv);
  /* Don't rely on the value of tv now! */

  if (retval == -1)
      perror("select()");
  else if (retval)
      printf("Data is available now.\n");  // i.e. doStuff()
      /* FD_ISSET(0, &rfds) will be true. */
  else
      printf("No data within five seconds.\n"); // i.e. key not pressed

Adding <script> to WordPress in <head> element

One way I like to use is Vanilla JavaScript with template literal:

var templateLiteral = [`
    <!-- HTML_CODE_COMES_HERE -->
`]

var head = document.querySelector("head");
head.innerHTML = templateLiteral;

Auto populate columns in one sheet from another sheet

Use the 'EntireColumn' property, that's what it is there for. C# snippet, but should give you a good indication of how to do this:

string rangeQuery = "A1:A1";

Range range = workSheet.get_Range(rangeQuery, Type.Missing);

range = range.EntireColumn;

How to listen state changes in react.js?

In 2020 you can listen state changes with useEffect hook like this

export function MyComponent(props) {
    const [myState, setMystate] = useState('initialState')

    useEffect(() => {
        console.log(myState, '- Has changed')
    },[myState]) // <-- here put the parameter to listen
}

Convert list to dictionary using linq and not worrying about duplicates

        DataTable DT = new DataTable();
        DT.Columns.Add("first", typeof(string));
        DT.Columns.Add("second", typeof(string));

        DT.Rows.Add("ss", "test1");
        DT.Rows.Add("sss", "test2");
        DT.Rows.Add("sys", "test3");
        DT.Rows.Add("ss", "test4");
        DT.Rows.Add("ss", "test5");
        DT.Rows.Add("sts", "test6");

        var dr = DT.AsEnumerable().GroupBy(S => S.Field<string>("first")).Select(S => S.First()).
            Select(S => new KeyValuePair<string, string>(S.Field<string>("first"), S.Field<string>("second"))).
           ToDictionary(S => S.Key, T => T.Value);

        foreach (var item in dr)
        {
            Console.WriteLine(item.Key + "-" + item.Value);
        }

Styling JQuery UI Autocomplete

Bootstrap styling for jQuery UI Autocomplete

    .ui-autocomplete {
    position: absolute;
    top: 100%;
    left: 0;
    z-index: 1000;
    float: left;
    display: none;
    min-width: 160px;   
    padding: 4px 0;
    margin: 0 0 10px 25px;
    list-style: none;
    background-color: #ffffff;
    border-color: #ccc;
    border-color: rgba(0, 0, 0, 0.2);
    border-style: solid;
    border-width: 1px;
    -webkit-border-radius: 5px;
    -moz-border-radius: 5px;
    border-radius: 5px;
    -webkit-box-shadow: 0 5px 10px rgba(0, 0, 0, 0.2);
    -moz-box-shadow: 0 5px 10px rgba(0, 0, 0, 0.2);
    box-shadow: 0 5px 10px rgba(0, 0, 0, 0.2);
    -webkit-background-clip: padding-box;
    -moz-background-clip: padding;
    background-clip: padding-box;
    *border-right-width: 2px;
    *border-bottom-width: 2px;
}

.ui-menu-item > a.ui-corner-all {
    display: block;
    padding: 3px 15px;
    clear: both;
    font-weight: normal;
    line-height: 18px;
    color: #555555;
    white-space: nowrap;
    text-decoration: none;
}

.ui-state-hover, .ui-state-active {
    color: #ffffff;
    text-decoration: none;
    background-color: #0088cc;
    border-radius: 0px;
    -webkit-border-radius: 0px;
    -moz-border-radius: 0px;
    background-image: none;
}

Bootstrap navbar Active State not working

I tried about first 5 solutions and different variations of them, but they didn't work for me.

Finally I got it working with these two functions.

$(document).on('click', '.nav-link', function () {
    $(".nav-item").find(".active").removeClass("active");
})

$(document).ready(function() {
    $('a[href="' + location.pathname + '"]').closest('.nav-item').addClass('active'); 
});

How do I convert NSInteger to NSString datatype?

The answer is given but think that for some situation this will be also interesting way to get string from NSInteger

NSInteger value = 12;
NSString * string = [NSString stringWithFormat:@"%0.0f", (float)value];

What are the differences between B trees and B+ trees?

Take one example - you have a table with huge data per row. That means every instance of the object is Big.

If you use B tree here then most of the time is spent scanning the pages with data - which is of no use. In databases that is the reason of using B+ Trees to avoid scanning object data.

B+ Trees separate keys from data.

But if your data size is less then you can store them with key which is what B tree does.

u'\ufeff' in Python string

That character is the BOM or "Byte Order Mark". It is usually received as the first few bytes of a file, telling you how to interpret the encoding of the rest of the data. You can simply remove the character to continue. Although, since the error says you were trying to convert to 'ascii', you should probably pick another encoding for whatever you were trying to do.

How do I populate a JComboBox with an ArrayList?

I don't like the accepted answer or @fivetwentysix's comment regarding how to solve this. It gets at one method for doing this, but doesn't give the full solution to using toArray. You need to use toArray and give it an argument that's an array of the correct type and size so that you don't end up with an Object array. While an object array will work, I don't think it's best practice in a strongly typed language.

String[] array = arrayList.toArray(new String[arrayList.size()]);
JComboBox comboBox = new JComboBox(array);

Alternatively, you can also maintain strong typing by just using a for loop.

String[] array = new String[arrayList.size()];
for(int i = 0; i < array.length; i++) {
    array[i] = arrayList.get(i);
}
JComboBox comboBox = new JComboBox(array);

How to get the first column of a pandas DataFrame as a Series?

This works great when you want to load a series from a csv file

x = pd.read_csv('x.csv', index_col=False, names=['x'],header=None).iloc[:,0]
print(type(x))
print(x.head(10))


<class 'pandas.core.series.Series'>
0    110.96
1    119.40
2    135.89
3    152.32
4    192.91
5    177.20
6    181.16
7    177.30
8    200.13
9    235.41
Name: x, dtype: float64

Remove "Using default security password" on Spring Boot

On spring boot 2 with webflux you need to define a ReactiveAuthenticationManager

What is the difference between required and ng-required?

I would like to make a addon for tiago's answer:

Suppose you're hiding element using ng-show and adding a required attribute on the same:

<div ng-show="false">
    <input required name="something" ng-model="name"/>
</div>

will throw an error something like :

An invalid form control with name='' is not focusable

This is because you just cannot impose required validation on hidden elements. Using ng-required makes it easier to conditionally apply required validation which is just awesome!!

List of strings to one string

string.Concat(los.ToArray());

If you just want to concatenate the strings then use string.Concat() instead of string.Join().

ActiveModel::ForbiddenAttributesError when creating new user

If using ActiveAdmin don't forget that there is also a permit_params in the model register block:

ActiveAdmin.register Api::V1::Person do
  permit_params :name, :address, :etc
end

These need to be set along with those in the controller:

def api_v1_person_params
  params.require(:api_v1_person).permit(:name, :address, :etc)
end

Otherwise you will get the error:

ActiveModel::ForbiddenAttributesError

Android: How to get a custom View's height and width?

Just got a solution to get height and width of a custom view:

@Override
protected void onSizeChanged(int xNew, int yNew, int xOld, int yOld){
    super.onSizeChanged(xNew, yNew, xOld, yOld);

    viewWidth = xNew;
    viewHeight = yNew;
}

Its working in my case.

C#: calling a button event handler method without actually clicking the button

It's just a method on your form, you can call it just like any other method. You just have to create an EventArgs object to pass to it, (and pass it the handle of the button as sender)

Best approach to remove time part of datetime in SQL Server

select CONVERT(char(10), GetDate(),126)

How can I get all the request headers in Django?

I don't think there is any easy way to get only HTTP headers. You have to iterate through request.META dict to get what all you need.

django-debug-toolbar takes the same approach to show header information. Have a look at this file responsible for retrieving header information.

How do I execute a command and get the output of the command within C++ using POSIX?

Two possible approaches:

  1. I don't think popen() is part of the C++ standard (it's part of POSIX from memory), but it's available on every UNIX I've worked with (and you seem to be targeting UNIX since your command is ./some_command).

  2. On the off-chance that there is no popen(), you can use system("./some_command >/tmp/some_command.out");, then use the normal I/O functions to process the output file.

What is the difference between persist() and merge() in JPA and Hibernate?

Persist should be called only on new entities, while merge is meant to reattach detached entities.

If you're using the assigned generator, using merge instead of persist can cause a redundant SQL statement.

Also, calling merge for managed entities is also a mistake since managed entities are automatically managed by Hibernate, and their state is synchronized with the database record by the dirty checking mechanism upon flushing the Persistence Context.

How do I get a value of datetime.today() in Python that is "timezone aware"?

In Python 3.2+: datetime.timezone.utc:

The standard library makes it much easier to specify UTC as the time zone:

>>> import datetime
>>> datetime.datetime.now(datetime.timezone.utc)
datetime.datetime(2020, 11, 27, 14, 34, 34, 74823, tzinfo=datetime.timezone.utc)

You can also get a datetime that includes the local time offset using astimezone:

>>> datetime.datetime.now(datetime.timezone.utc).astimezone()
datetime.datetime(2020, 11, 27, 15, 34, 34, 74823, tzinfo=datetime.timezone(datetime.timedelta(seconds=3600), 'CET'))

(In Python 3.6+, you can shorten the last line to: datetime.datetime.now().astimezone())

If you want a solution that uses only the standard library and that works in both Python 2 and Python 3, see jfs' answer.

In Python 3.9+: zoneinfo to use the IANA time zone database:

In Python 3.9, you can specify particular time zones using the standard library, using zoneinfo, like this:

>>> from zoneinfo import ZoneInfo
>>> datetime.datetime.now(ZoneInfo("America/Los_Angeles"))
datetime.datetime(2020, 11, 27, 6, 34, 34, 74823, tzinfo=zoneinfo.ZoneInfo(key='America/Los_Angeles'))

zoneinfo gets its database of time zones from the operating system, or from the first-party PyPI package tzdata if available.

Set CFLAGS and CXXFLAGS options using CMake

You must change the cmake C/CXX default FLAGS .

According to CMAKE_BUILD_TYPE={DEBUG/MINSIZEREL/RELWITHDEBINFO/RELEASE} put in the main CMakeLists.txt one of :

For C

set(CMAKE_C_FLAGS_DEBUG "put your flags")
set(CMAKE_C_FLAGS_MINSIZEREL "put your flags")
set(CMAKE_C_FLAGS_RELWITHDEBINFO "put your flags")
set(CMAKE_C_FLAGS_RELEASE "put your flags")

For C++

set(CMAKE_CXX_FLAGS_DEBUG "put your flags")
set(CMAKE_CXX_FLAGS_MINSIZEREL "put your flags")
set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "put your flags")
set(CMAKE_CXX_FLAGS_RELEASE "put your flags")

This will override the values defined in CMakeCache.txt

How can I do factory reset using adb in android?

I have made it from fastboot mode (Phone - Xiomi Mi5 Android 6.0.1)

Here is steps:

# check if device available
fastboot devices
# remove user data
fastboot erase userdata
# remove cache
fastboot erase cache 
# reboot device
fastboot reboot

how to rotate text left 90 degree and cell size is adjusted according to text in html

Without calculating height. Strict CSS and HTML. <span/> only for Chrome, because the chrome isn't able change text direction for <th/>.

_x000D_
_x000D_
th _x000D_
{_x000D_
  vertical-align: bottom;_x000D_
  text-align: center;_x000D_
}_x000D_
_x000D_
th span _x000D_
{_x000D_
  -ms-writing-mode: tb-rl;_x000D_
  -webkit-writing-mode: vertical-rl;_x000D_
  writing-mode: vertical-rl;_x000D_
  transform: rotate(180deg);_x000D_
  white-space: nowrap;_x000D_
}
_x000D_
<table>_x000D_
  <tr>_x000D_
    <th><span>Rotated text by 90 deg.</span></th>_x000D_
  </tr>_x000D_
</table>
_x000D_
_x000D_
_x000D_

getting the X/Y coordinates of a mouse click on an image with jQuery

You can use pageX and pageY to get the position of the mouse in the window. You can also use jQuery's offset to get the position of an element.

So, it should be pageX - offset.left for how far from the left of the image and pageY - offset.top for how far from the top of the image.

Here is an example:

$(document).ready(function() {
  $('img').click(function(e) {
    var offset = $(this).offset();
    alert(e.pageX - offset.left);
    alert(e.pageY - offset.top);
  });
});

I've made a live example here and here is the source.

To calculate how far from the bottom or right, you would have to use jQuery's width and height methods.

How to add a changed file to an older (not last) commit in Git

Use git rebase. Specifically:

  1. Use git stash to store the changes you want to add.
  2. Use git rebase -i HEAD~10 (or however many commits back you want to see).
  3. Mark the commit in question (a0865...) for edit by changing the word pick at the start of the line into edit. Don't delete the other lines as that would delete the commits.[^vimnote]
  4. Save the rebase file, and git will drop back to the shell and wait for you to fix that commit.
  5. Pop the stash by using git stash pop
  6. Add your file with git add <file>.
  7. Amend the commit with git commit --amend --no-edit.
  8. Do a git rebase --continue which will rewrite the rest of your commits against the new one.
  9. Repeat from step 2 onwards if you have marked more than one commit for edit.

[^vimnote]: If you are using vim then you will have to hit the Insert key to edit, then Esc and type in :wq to save the file, quit the editor, and apply the changes. Alternatively, you can configure a user-friendly git commit editor with git config --global core.editor "nano".

How to use a wildcard in the classpath to add multiple jars?

Basename wild cards were introduced in Java 6; i.e. "foo/*" means all ".jar" files in the "foo" directory.

In earlier versions of Java that do not support wildcard classpaths, I have resorted to using a shell wrapper script to assemble a Classpath by 'globbing' a pattern and mangling the results to insert ':' characters at the appropriate points. This would be hard to do in a BAT file ...

Select parent element of known element in Selenium

This might be useful for someone else: Using this sample html

<div class="ParentDiv">
    <label for="label">labelName</label>
    <input type="button" value="elementToSelect">
</div>
<div class="DontSelect">
    <label for="animal">pig</label>
    <input type="button" value="elementToSelect">
</div>

If for example, I want to select an element in the same section (e.g div) as a label, you can use this

//label[contains(., 'labelName')]/parent::*//input[@value='elementToSelect'] 

This just means, look for a label (it could anything like a, h2) called labelName. Navigate to the parent of that label (i.e. div class="ParentDiv"). Search within the descendants of that parent to find any child element with the value of elementToSelect. With this, it will not select the second elementToSelect with DontSelect div as parent.

The trick is that you can reduce search areas for an element by navigating to the parent first and then searching descendant of that parent for the element you need. Other Syntax like following-sibling::h2 can also be used in some cases. This means the sibling following element h2. This will work for elements at the same level, having the same parent.

How can a Javascript object refer to values in itself?

You can also reference the obj once you are inside the function instead of this.

var obj = {
    key1: "it",
    key2: function(){return obj.key1 + " works!"}
};
alert(obj.key2());

how to parse a "dd/mm/yyyy" or "dd-mm-yyyy" or "dd-mmm-yyyy" formatted date string using JavaScript or jQuery

Try this:

 function GetDateFormat(controlName) {
        if ($('#' + controlName).val() != "") {      
            var d1 = Date.parse($('#' + controlName).val().toString().replace(/([0-9]+)\/([0-9]+)/,'$2/$1'));
            if (d1 == null) {
                alert('Date Invalid.');
                $('#' + controlName).val("");
            }
                var array = d1.toString('dd-MMM-yyyy');
                $('#' + controlName).val(array);
        }
    }

The RegExp replace .replace(/([0-9]+)\/([0-9]+)/,'$2/$1') change day/month position.

Where is Android Studio layout preview?

Go to File > Settings > Appearance & Behavior > Appearance > Show tool window bars

How do I use .woff fonts for my website?

You need to declare @font-face like this in your stylesheet

@font-face {
  font-family: 'Awesome-Font';
  font-style: normal;
  font-weight: 400;
  src: local('Awesome-Font'), local('Awesome-Font-Regular'), url(path/Awesome-Font.woff) format('woff');
}

Now if you want to apply this font to a paragraph simply use it like this..

p {
font-family: 'Awesome-Font', Arial;
}

More Reference

How to add image in a TextView text?

This answer is based on this excellent answer by 18446744073709551615. Their solution, though helpful, does not size the image icon with the surrounding text. It also doesn't set the icon colour to that of the surrounding text.

The solution below takes a white, square icon and makes it fit the size and colour of the surrounding text.

public class TextViewWithImages extends TextView {

    private static final String DRAWABLE = "drawable";
    /**
     * Regex pattern that looks for embedded images of the format: [img src=imageName/]
     */
    public static final String PATTERN = "\\Q[img src=\\E([a-zA-Z0-9_]+?)\\Q/]\\E";

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

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

    public TextViewWithImages(Context context) {
        super(context);
    }

    @Override
    public void setText(CharSequence text, BufferType type) {
        final Spannable spannable = getTextWithImages(getContext(), text, getLineHeight(), getCurrentTextColor());
        super.setText(spannable, BufferType.SPANNABLE);
    }

    private static Spannable getTextWithImages(Context context, CharSequence text, int lineHeight, int colour) {
        final Spannable spannable = Spannable.Factory.getInstance().newSpannable(text);
        addImages(context, spannable, lineHeight, colour);
        return spannable;
    }

    private static boolean addImages(Context context, Spannable spannable, int lineHeight, int colour) {
        final Pattern refImg = Pattern.compile(PATTERN);
        boolean hasChanges = false;

        final Matcher matcher = refImg.matcher(spannable);
        while (matcher.find()) {
            boolean set = true;
            for (ImageSpan span : spannable.getSpans(matcher.start(), matcher.end(), ImageSpan.class)) {
                if (spannable.getSpanStart(span) >= matcher.start()
                        && spannable.getSpanEnd(span) <= matcher.end()) {
                    spannable.removeSpan(span);
                } else {
                    set = false;
                    break;
                }
            }
            final String resName = spannable.subSequence(matcher.start(1), matcher.end(1)).toString().trim();
            final int id = context.getResources().getIdentifier(resName, DRAWABLE, context.getPackageName());
            if (set) {
                hasChanges = true;
                spannable.setSpan(makeImageSpan(context, id, lineHeight, colour),
                        matcher.start(),
                        matcher.end(),
                        Spannable.SPAN_EXCLUSIVE_EXCLUSIVE
                );
            }
        }
        return hasChanges;
    }

    /**
     * Create an ImageSpan for the given icon drawable. This also sets the image size and colour.
     * Works best with a white, square icon because of the colouring and resizing.
     *
     * @param context       The Android Context.
     * @param drawableResId A drawable resource Id.
     * @param size          The desired size (i.e. width and height) of the image icon in pixels.
     *                      Use the lineHeight of the TextView to make the image inline with the
     *                      surrounding text.
     * @param colour        The colour (careful: NOT a resource Id) to apply to the image.
     * @return An ImageSpan, aligned with the bottom of the text.
     */
    private static ImageSpan makeImageSpan(Context context, int drawableResId, int size, int colour) {
        final Drawable drawable = context.getResources().getDrawable(drawableResId);
        drawable.mutate();
        drawable.setColorFilter(colour, PorterDuff.Mode.MULTIPLY);
        drawable.setBounds(0, 0, size, size);
        return new ImageSpan(drawable, ImageSpan.ALIGN_BOTTOM);
    }

}

How to use:

Simply embed references to the desired icons in the text. It doesn't matter whether the text is set programatically through textView.setText(R.string.string_resource); or if it's set in xml.

To embed a drawable icon named example.png, include the following string in the text: [img src=example/].

For example, a string resource might look like this:

<string name="string_resource">This [img src=example/] is an icon.</string>

How to deal with SettingWithCopyWarning in Pandas

The SettingWithCopyWarning was created to flag potentially confusing "chained" assignments, such as the following, which does not always work as expected, particularly when the first selection returns a copy. [see GH5390 and GH5597 for background discussion.]

df[df['A'] > 2]['B'] = new_val  # new_val not set in df

The warning offers a suggestion to rewrite as follows:

df.loc[df['A'] > 2, 'B'] = new_val

However, this doesn't fit your usage, which is equivalent to:

df = df[df['A'] > 2]
df['B'] = new_val

While it's clear that you don't care about writes making it back to the original frame (since you are overwriting the reference to it), unfortunately this pattern cannot be differentiated from the first chained assignment example. Hence the (false positive) warning. The potential for false positives is addressed in the docs on indexing, if you'd like to read further. You can safely disable this new warning with the following assignment.

import pandas as pd
pd.options.mode.chained_assignment = None  # default='warn'

Other Resources

What does it mean "No Launcher activity found!"

Here's an example from AndroidManifest.xml. You need to specify the MAIN and LAUNCHER in the intent filter for the activity you want to start on launch

<application android:label="@string/app_name" android:icon="@drawable/icon">
    <activity android:name="ExampleActivity"
              android:label="@string/app_name">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
</application>

jquery smooth scroll to an anchor?

I used the plugin Smooth Scroll, at http://plugins.jquery.com/smooth-scroll/. With this plugin all you need to include is a link to jQuery and to the plugin code:

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<script type="text/javascript" src="javascript/smoothscroll.js"></script>

(the links need to have the class smoothScroll to work).

Another feature of Smooth Scroll is that the ancor name is not displayed in the URL!

How to fix syntax error, unexpected T_IF error in php?

PHP parser errors take some getting used to; if it complains about an unexpected 'something' at line X, look at line X-1 first. In this case it will not tell you that you forgot a semi-colon at the end of the previous line , instead it will complain about the if that comes next.

You'll get used to it :)

File upload progress bar with jQuery

Here is a more complete looking jquery 1.11.x $.ajax() usage:

<script type="text/javascript">
    function uploadProgressHandler(event) {
        $("#loaded_n_total").html("Uploaded " + event.loaded + " bytes of " + event.total);
        var percent = (event.loaded / event.total) * 100;
        var progress = Math.round(percent);
        $("#uploadProgressBar").html(progress + " percent na ang progress");
        $("#uploadProgressBar").css("width", progress + "%");
        $("#status").html(progress + "% uploaded... please wait");
    }

    function loadHandler(event) {
        $("#status").html(event.target.responseText);
        $("#uploadProgressBar").css("width", "0%");
    }

    function errorHandler(event) {
        $("#status").html("Upload Failed");
    }

    function abortHandler(event) {
        $("#status").html("Upload Aborted");
    }

    $("#uploadFile").click(function (event) {
        event.preventDefault();
        var file = $("#fileUpload")[0].files[0];
        var formData = new FormData();
        formData.append("file1", file);

        $.ajax({
            url: 'http://testarea.local/UploadWithProgressBar1/file_upload_parser.php',
            method: 'POST',
            type: 'POST',
            data: formData,
            contentType: false,
            processData: false,
            xhr: function () {
                var xhr = new window.XMLHttpRequest();
                xhr.upload.addEventListener("progress",
                    uploadProgressHandler,
                    false
                );
                xhr.addEventListener("load", loadHandler, false);
                xhr.addEventListener("error", errorHandler, false);
                xhr.addEventListener("abort", abortHandler, false);

                return xhr;
            }
        });
    });
</script>

Getting time and date from timestamp with php

$timestamp='2014-11-21 16:38:00';

list($date,$time)=explode(' ',$timestamp);

// just time

preg_match("/ (\d\d:\d\d):\d\d$/",$timestamp,$match);
echo "\n<br>".$match[1];

Java - Convert integer to string

Always use either String.valueOf(number) or Integer.toString(number).

Using "" + number is an overhead and does the following:

StringBuilder sb = new StringBuilder();
sb.append("");
sb.append(number);
return sb.toString();

Adjust icon size of Floating action button (fab)

The design guidelines defines two sizes and unless there is a strong reason to deviate from using either, the size can be controlled with the fabSize XML attribute of the FloatingActionButton component.

Consider specifying using either app:fabSize="normal" or app:fabSize="mini", e.g.:

<android.support.design.widget.FloatingActionButton
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:src="@drawable/ic_done_white_24px"
   app:fabSize="mini" />

How to filter Android logcat by application?

my .bash_profile function, it may be of any use

logcat() {
    if [ -z "$1" ]
    then
        echo "Process Id argument missing."; return
    fi
    pidFilter="\b$1\b"
    pid=$(adb shell ps | egrep $pidFilter | cut -c10-15)
    if [ -z "$pid" ]
    then
        echo "Process $1 is not running."; return
    fi
    adb logcat | grep $pid
}

alias logcat-myapp="logcat com.sample.myapp"

Usage:

$ logcat-myapp

$ logcat com.android.something.app

SQL statement to select all rows from previous day

SELECT * from table_name where date_field = DATE_SUB(CURRENT_DATE(),INTERVAL 1 DAY);

File Not Found when running PHP with Nginx

The error message “Primary script unknown or in your case is file not found.” is almost always related to a wrongly set in line SCRIPT_FILENAME in the Nginx fastcgi_param directive (Quote from https://serverfault.com/a/517327/560171).

In my case, I use Nginx 1.17.10 and my configuration is:

    location ~ \.php$ {
      fastcgi_pass unix:/var/run/php/php7.2-fpm.sock;
      fastcgi_index index.php;
      fastcgi_param SCRIPT_FILENAME $realpath_root$fastcgi_script_name;
      include fastcgi_params;
      fastcgi_read_timeout 600;
    }

You just change $document_root to $realpath_root, so whatever your root location, like /var/www/html/project/, you don't need write fastcgi_param SCRIPT_FILENAME /var/www/html/project$fastcgi_script_name; each time your root is changes. This configuration is more flexible. May this helps.

=================================================================================

For more information, if you got unix:/run/php/php7.2-fpm.sock failed (13: Permission denied) while connecting to upstream, just change in /etc/nginx/nginx.conf, from user nginx; to user www-data;.

Because the default user and group of PHP-FPM process is www-data as can be seen in /etc/php/7.2/fpm/pool.d/www.conf file (Qoute from https://www.linuxbabe.com/ubuntu/install-nginx-latest-version-ubuntu-18-04):

user = www-data
group = www-data

May this information gives a big help

Fill Combobox from database

void Fillcombobox()
{

    con.Open();
    cmd = new SqlCommand("select ID From Employees",con);
    Sdr = cmd.ExecuteReader();
    while (Sdr.Read())
    {
        for (int i = 0; i < Sdr.FieldCount; i++)
        {
           comboID.Items.Add( Sdr.GetString(i));

        }
    }
    Sdr.Close();
    con.Close();

}

Differences in string compare methods in C#

In the forms you listed here, there's not much difference between the two. CompareTo ends up calling a CompareInfo method that does a comparison using the current culture; Equals is called by the == operator.

If you consider overloads, then things get different. Compare and == can only use the current culture to compare a string. Equals and String.Compare can take a StringComparison enumeration argument that let you specify culture-insensitive or case-insensitive comparisons. Only String.Compare allows you to specify a CultureInfo and perform comparisons using a culture other than the default culture.

Because of its versatility, I find I use String.Compare more than any other comparison method; it lets me specify exactly what I want.

Git branching: master vs. origin/master vs. remotes/origin/master

One clarification (and a point that confused me):

"remotes/origin/HEAD is the default branch" is not really correct.

remotes/origin/master was the default branch in the remote repository (last time you checked). HEAD is not a branch, it just points to a branch.

Think of HEAD as your working area. When you think of it this way then 'git checkout branchname' makes sense with respect to changing your working area files to be that of a particular branch. You "checkout" branch files into your working area. HEAD for all practical purposes is what is visible to you in your working area.

OS X Terminal Colors

You can use the Linux based syntax in one of your startup scripts. Just tested this on an OS X Mountain Lion box.

eg. in your ~/.bash_profile

export TERM="xterm-color" 
export PS1='\[\e[0;33m\]\u\[\e[0m\]@\[\e[0;32m\]\h\[\e[0m\]:\[\e[0;34m\]\w\[\e[0m\]\$ '

This gives you a nice colored prompt. To add the colored ls output, you can add alias ls="ls -G".

To test, just run a source ~/.bash_profile to update your current terminal.

Side note about the colors: The colors are preceded by an escape sequence \e and defined by a color value, composed of [style;color+m] and wrapped in an escaped [] sequence. eg.

  • red = \[\e[0;31m\]
  • bold red (style 1) = \[\e[1;31m\]
  • clear coloring = \[\e[0m\]

I always add a slightly modified color-scheme in the root's .bash_profile to make the username red, so I always see clearly if I'm logged in as root (handy to avoid mistakes if I have many terminal windows open).

In /root/.bash_profile:

PS1='\[\e[0;31m\]\u\[\e[0m\]@\[\e[0;32m\]\h\[\e[0m\]:\[\e[0;34m\]\w\[\e[0m\]\$ '

For all my SSH accounts online I make sure to put the hostname in red, to distinguish if I'm in a local or remote terminal. Just edit the .bash_profile file in your home dir on the server.. If there is no .bash_profile file on the server, you can create it and it should be sourced upon login.

If this is not working as expected for you, please read some of the comments below since I'm not using MacOS very often..

If you want to do this on a remote server, check if the ~/.bash_profile file exists. If not, simply create it and it should be automatically sourced upon your next login.

Dark color scheme for Eclipse

I have finally found exactly what I have been looking for, i.e. a dark theme for PyDev (although I still feel like Eclipse is missing out on this).

Can a table row expand and close?

Yes, a table row can slide up and down, but it's ugly, since it changes the shape of the table and makes everything jump. Instead, put and element in each td... something that makes sense like a p or h2 etc.

For how to implement a table slide toggle...

It's probably simplest to put the click handler on the entire table, .stopPropagation() and check what was clicked.

If a td in a row with a colspan is clicked, close the p in it. If it's not a td in a row with a colspan, then close then toggle the following row's p.

It is essentially to wrap all your written content in an element inside the tds, since you never want to slideUp a td or tr or table shape will change!

Something like:

$(function() {

      // Initially hide toggleable content
    $("td[colspan=3]").find("p").hide();

      // Click handler on entire table
    $("table").click(function(event) {

          // No bubbling up
        event.stopPropagation();

        var $target = $(event.target);

          // Open and close the appropriate thing
        if ( $target.closest("td").attr("colspan") > 1 ) {
            $target.slideUp();
        } else {
            $target.closest("tr").next().find("p").slideToggle();
        }                    
    });
});?

Try it out with this jsFiddle example.

... and try out this jsFiddle showing implementation of a + - - toggle.

The HTML just has to have alternating rows of several tds and then a row with a td of a colspan greater than 1. You can obviously adjust the specifics quite easily.

The HTML would look something like:

<table>
    <tr><td><p>Name</p></td><td><p>Age</p></td><td><p>Info</p></td></tr>
    <tr><td colspan="3"><p>Blah blah blah blah blah blah blah.</p>
    </td></tr>

    <tr><td><p>Name</p></td><td><p>Age</p></td><td><p>Info</p></td></tr>
    <tr><td colspan="3"><p>Blah blah blah blah blah blah blah.</p>
    </td></tr>

    <tr><td><p>Name</p></td><td><p>Age</p></td><td><p>Info</p></td></tr>
    <tr><td colspan="3"><p>Blah blah blah blah blah blah blah.</p>
    </td></tr>    
</table>?

Convert/cast an stdClass object to another class

And yet another approach using the decorator pattern and PHPs magic getter & setters:

// A simple StdClass object    
$stdclass = new StdClass();
$stdclass->foo = 'bar';

// Decorator base class to inherit from
class Decorator {

    protected $object = NULL;

    public function __construct($object)
    {
       $this->object = $object;  
    }

    public function __get($property_name)
    {
        return $this->object->$property_name;   
    }

    public function __set($property_name, $value)
    {
        $this->object->$property_name = $value;   
    }
}

class MyClass extends Decorator {}

$myclass = new MyClass($stdclass)

// Use the decorated object in any type-hinted function/method
function test(MyClass $object) {
    echo $object->foo . '<br>';
    $object->foo = 'baz';
    echo $object->foo;   
}

test($myclass);

removing bold styling from part of a header

You could wrap the not-bold text into a span and give the span the following properties:

.notbold{
    font-weight:normal
}?

and

<h1>**This text should be bold**, <span class='notbold'>but this text should not</span></h1>

See: http://jsfiddle.net/MRcpa/1/

Use <span> when you want to change the style of elements without placing them in a new block-level element in the document.

Correct file permissions for WordPress

For those who have their wordpress root folder under their home folder:

** Ubuntu/apache

  1. Add your user to www-data group:

CREDIT Granting write permissions to www-data group

You want to call usermod on your user. So that would be:

sudo usermod -aG www-data yourUserName

** Assuming www-data group exists

  1. Check your user is in www-data group:

    groups yourUserName

You should get something like:

youUserName : youUserGroupName www-data

** youUserGroupName is usually similar to you user name

  1. Recursively change group ownership of the wp-content folder keeping your user ownership

    chown yourUserName:www-data -R youWebSiteFolder/wp-content/*

  2. Change directory to youWebSiteFolder/wp-content/

    cd youWebSiteFolder/wp-content

  3. Recursively change group permissions of the folders and sub-folders to enable write permissions:

    find . -type d -exec chmod -R 775 {} \;

** mode of `/home/yourUserName/youWebSiteFolder/wp-content/' changed from 0755 (rwxr-xr-x) to 0775 (rwxrwxr-x)

  1. Recursively change group permissions of the files and sub-files to enable write permissions:

    find . -type f -exec chmod -R 664 {} \;

The result should look something like:

WAS:
-rw-r--r--  1 yourUserName www-data  7192 Oct  4 00:03 filename.html
CHANGED TO:
-rw-rw-r--  1 yourUserName www-data  7192 Oct  4 00:03 filename.html

Equivalent to:

chmod -R ug+rw foldername

Permissions will be like 664 for files or 775 for directories.

P.s. if anyone encounters error 'could not create directory' when updating a plugin, do:
server@user:~/domainame.com$ sudo chown username:www-data -R wp-content
when you are at the root of your domain.
Assuming: wp-config.php has
FTP credentials on LocalHost
define('FS_METHOD','direct');

How do I change the background of a Frame in Tkinter?

You use ttk.Frame, bg option does not work for it. You should create style and apply it to the frame.

from tkinter import *
from tkinter.ttk import * 

root = Tk()

s = Style()
s.configure('My.TFrame', background='red')

mail1 = Frame(root, style='My.TFrame')
mail1.place(height=70, width=400, x=83, y=109)
mail1.config()
root.mainloop()

REST API - file (ie images) processing - best practices

There's no easy solution. Each way has their pros and cons . But the canonical way is using the first option: multipart/form-data. As W3 recommendation guide says

The content type "multipart/form-data" should be used for submitting forms that contain files, non-ASCII data, and binary data.

We aren't sending forms,really, but the implicit principle still applies. Using base64 as a binary representation, is incorrect because you're using the incorrect tool for accomplish your goal, in other hand, the second option forces your API clients to do more job in order to consume your API service. You should do the hard work in the server side in order to supply an easy-to-consume API. The first option is not easy to debug, but when you do it, it probably never changes.

Using multipart/form-data you're sticked with the REST/http philosophy. You can view an answer to similar question here.

Another option if mixing the alternatives, you can use multipart/form-data but instead of send every value separate, you can send a value named payload with the json payload inside it. (I tried this approach using ASP.NET WebAPI 2 and works fine).

What version of Python is on my Mac?

You could have multiple Python versions on your macOS.

You may check that by command, type or which command, like:

which -a python python2 python2.7 python3 python3.6

Or type python in Terminal and hit Tab few times for auto completion, which is equivalent to:

compgen -c python

By default python/pip commands points to the first binary found in PATH environment variable depending what's actually installed. So before installing Python packages with Homebrew, the default Python is installed in /usr/bin which is shipped with your macOS (e.g. Python 2.7.10 on High Sierra). Any versions found in /usr/local (such as /usr/local/bin) are provided by external packages.

It is generally advised, that when working with multiple versions, for Python 2 you may use python2/pip2 command, respectively for Python 3 you can use python3/pip3, but it depends on your configuration which commands are available.

It is also worth to mention, that since release of Homebrew 1.5.0+ (on 19 January 2018), the python formula has been upgraded to Python 3.x and a python@2 formula will be added for installing Python 2.7. Before, python formula was pointing to Python 2.

For instance, if you've installed different version via Homebrew, try the following command:

brew list python python3

or:

brew list | grep ^python

it'll show you all Python files installed with the package.

Alternatively you may use apropos or locate python command to locate more Python related files.

To check any environment variables related to Python, run:

env | grep ^PYTHON

To address your issues:

  • Error: No such keg: /usr/local/Cellar/python

    Means you don't have Python installed via Homebrew. However double check by specifying only one package at a time (like brew list python python2 python3).

  • The locate database (/var/db/locate.database) does not exist.

    Follow the advice and run:

    sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.locate.plist
    

    After the database is rebuild, you can use locate command.

How do I dispatch_sync, dispatch_async, dispatch_after, etc in Swift 3, Swift 4, and beyond?

in Xcode 8 use:

DispatchQueue.global(qos: .userInitiated).async { }

CSS: auto height on containing div, 100% height on background div inside containing div

You shouldn't have to set height: 100% at any point if you want your container to fill the page. Chances are, your problem is rooted in the fact that you haven't cleared the floats in the container's children. There are quite a few ways to solve this problem, mainly adding overflow: hidden to the container.

#container { overflow: hidden; }

Should be enough to solve whatever height problem you're having.

Saving the PuTTY session logging

I always have to check my cheatsheet :-)

Step 1: right-click on the top of putty window and select 'Change settings'.

Step 2: type the name of the session and save.

That's it!. Enjoy!

Add vertical whitespace using Twitter Bootstrap?

Sorry to dig an old grave here, but why not just do this?

<div class="form-group">
    &nbsp;
</div>

It will add a space the height of a normal form element.

It seems about 1 line on a form is roughly 50px (47px on my element I just inspected). This is a horizontal form, with label on left 2col and input on right 10col. So your pixels may vary.

Since mine is basically 50px, I would create a spacer of 50px tall with no margins or padding;

.spacer { margin:0; padding:0; height:50px; }
<div class="spacer"></div>

json.net has key method?

JObject implements IDictionary<string, JToken>, so you can use:

IDictionary<string, JToken> dictionary = x;
if (dictionary.ContainsKey("error_msg"))

... or you could use TryGetValue. It implements both methods using explicit interface implementation, so you can't use them without first converting to IDictionary<string, JToken> though.

What I can do to resolve "1 commit behind master"?

Use

git cherry-pick <commit-hash>

So this will pick your behind commit to git location you are on.

How to modify values of JsonObject / JsonArray directly?

This works for modifying childkey value using JSONObject. import used is

import org.json.JSONObject;

ex json:(convert json file to string while giving as input)

{
    "parentkey1": "name",
    "parentkey2": {
     "childkey": "test"
    },
}

Code

JSONObject jObject  = new JSONObject(String jsoninputfileasstring);
jObject.getJSONObject("parentkey2").put("childkey","data1");
System.out.println(jObject);

output:

{
    "parentkey1": "name",
    "parentkey2": {
     "childkey": "data1"
    },
}

How to perform element-wise multiplication of two lists?

create an array of ones; multiply each list times the array; convert array to a list

import numpy as np

a = [1,2,3,4]
b = [2,3,4,5]

c = (np.ones(len(a))*a*b).tolist()

[2.0, 6.0, 12.0, 20.0]

How to get a list of column names

The result set of a query in PHP offers a couple of functions allowing just that:

    numCols() 
    columnName(int $column_number )

Example

    $db = new SQLIte3('mysqlite.db');
    $table = 'mytable';

    $tableCol = getColName($db, $table);

    for ($i=0; $i<count($tableCol); $i++){
        echo "Column $i = ".$tableCol[$i]."\n";
    }           

    function getColName($db, $table){
        $qry = "SELECT * FROM $table LIMIT 1";
        $result = $db->query($qry);
        $nCols = $result->numCols();
        for ($i = 0; $i < $ncols; $i++) {
            $colName[$i] = $result->columnName($i);
        }
        return $colName;
    }

How to round a numpy array?

It is worth noting that the accepted answer will round small floats down to zero.

>>> import numpy as np 
>>> arr = np.asarray([2.92290007e+00, -1.57376965e-03, 4.82011728e-08, 1.92896977e-12])
>>> print(arr)
[ 2.92290007e+00 -1.57376965e-03  4.82011728e-08  1.92896977e-12]
>>> np.round(arr, 2)
array([ 2.92, -0.  ,  0.  ,  0.  ]) 

You can use set_printoptions and a custom formatter to fix this and get a more numpy-esque printout with fewer decimal places:

>>> np.set_printoptions(formatter={'float': "{0:0.2e}".format})
>>> print(arr)
[2.92e+00 -1.57e-03 4.82e-08 1.93e-12]  

This way, you get the full versatility of format and maintain the full precision of numpy's datatypes.

Also note that this only affects printing, not the actual precision of the stored values used for computation.

Accessing Imap in C#

MailSystem.NET contains all your need for IMAP4. It's free & open source.

(I'm involved in the project)

How to read a line from the console in C?

The best and simplest way to read a line from a console is using the getchar() function, whereby you will store one character at a time in an array.

{
char message[N];        /* character array for the message, you can always change the character length */
int i = 0;          /* loop counter */

printf( "Enter a message: " );
message[i] = getchar();    /* get the first character */
while( message[i] != '\n' ){
    message[++i] = getchar(); /* gets the next character */
}

printf( "Entered message is:" );
for( i = 0; i < N; i++ )
    printf( "%c", message[i] );

return ( 0 );

}

jQuery ajax post file field

File uploads can not be done this way, no matter how you break it down. If you want to do an ajax/async upload, I would suggest looking into something like Uploadify, or Valums

How to check for file existence

Check out Pathname and in particular Pathname#exist?.

File and its FileTest module are perhaps simpler/more direct, but I find Pathname a nicer interface in general.

Insert current date in datetime format mySQL

set the type of column named dateposted as DATETIME and run the following query:

INSERT INTO table (`dateposted`) VALUES (CURRENT_TIMESTAMP)

How can I convert a zero-terminated byte array to string?

For example,

package main

import "fmt"

func CToGoString(c []byte) string {
    n := -1
    for i, b := range c {
        if b == 0 {
            break
        }
        n = i
    }
    return string(c[:n+1])
}

func main() {
    c := [100]byte{'a', 'b', 'c'}
    fmt.Println("C: ", len(c), c[:4])
    g := CToGoString(c[:])
    fmt.Println("Go:", len(g), g)
}

Output:

C:  100 [97 98 99 0]
Go: 3 abc

How to install MySQLi on MacOS

Since you are using a Mac, open a terminal, and

  • cd /etc

Find the php.ini, and sudo open it, for example, using the nano editor

  • nano php.ini

Find use control+w to search for "mysqli.default_socket", and change the line to

  • mysqli.default_socket = /tmp/mysql.sock

Use control+x and then hit "y" and "return" to save the file. Restart Aapche if necessary.

Now you should be able to run mysqli.

Open Google Chrome from VBA/Excel

shell("C:\Users\USERNAME\AppData\Local\Google\Chrome\Application\Chrome.exe -url http:google.ca")

An error occurred while executing the command definition. See the inner exception for details

In my case, It was from Stored Producers. I was removed a field from table and forgotten to remove it from my SP.

taking input of a string word by word

Put the line in a stringstream and extract word by word back:

#include <iostream>
#include <sstream>
using namespace std;

int main()
{
    string t;
    getline(cin,t);

    istringstream iss(t);
    string word;
    while(iss >> word) {
        /* do stuff with word */
    }
}

Of course, you can just skip the getline part and read word by word from cin directly.

And here you can read why is using namespace std considered bad practice.

QUERY syntax using cell reference

I found out that single quote > double quote > wrapped in ampersands did work. So, for me it looks like this:

=QUERY('Youth Conference Registration'!C:Y,"select C where Y = '"&A1&"'", 0)

How to check if a file is a valid image file?

format = [".jpg",".png",".jpeg"]
 for (path,dirs,files) in os.walk(path):
     for file in files:
         if file.endswith(tuple(format)):
             print(path)
             print ("Valid",file)
         else:
             print(path)
             print("InValid",file)

File input 'accept' attribute - is it useful?

If the browser uses this attribute, it is only as an help for the user, so he won't upload a multi-megabyte file just to see it rejected by the server...
Same for the <input type="hidden" name="MAX_FILE_SIZE" value="100000"> tag: if the browser uses it, it won't send the file but an error resulting in UPLOAD_ERR_FORM_SIZE (2) error in PHP (not sure how it is handled in other languages).
Note these are helps for the user. Of course, the server must always check the type and size of the file on its end: it is easy to tamper with these values on the client side.

Infinite Recursion with Jackson JSON and Hibernate JPA issue

VERY IMPORTANT: If you are using LOMBOK, make shure to exclude attributes of collections like Set, List, etc...

Like this:

@EqualsAndHashCode(exclude = {"attributeOfTypeList", "attributeOfTypeSet"})

What's the correct way to communicate between controllers in AngularJS?

You can access this hello function anywhere in the module

Controller one

 $scope.save = function() {
    $scope.hello();
  }

second controller

  $rootScope.hello = function() {
    console.log('hello');
  }

More info here

PHP: Call to undefined function: simplexml_load_string()

I also faced this issue. My Operating system is Ubuntu 18.04 and my PHP version is PHP 7.2.

Here's how I solved it:

Install Simplexml on your Ubuntu Server:

sudo apt-get install php7.2-simplexml

Restart Apache Server

sudo systemctl restart apache2

That's all.

I hope this helps

How can I send an email through the UNIX mailx command?

Here you are :

echo "Body" | mailx -r "FROM_EMAIL" -s "SUBJECT" "To_EMAIL"

PS. Body and subject should be kept within double quotes. Remove quotes from FROM_EMAIL and To_EMAIL while substituting email addresses.

How to take the first N items from a generator or list?

In my taste, it's also very concise to combine zip() with xrange(n) (or range(n) in Python3), which works nice on generators as well and seems to be more flexible for changes in general.

# Option #1: taking the first n elements as a list
[x for _, x in zip(xrange(n), generator)]

# Option #2, using 'next()' and taking care for 'StopIteration'
[next(generator) for _ in xrange(n)]

# Option #3: taking the first n elements as a new generator
(x for _, x in zip(xrange(n), generator))

# Option #4: yielding them by simply preparing a function
# (but take care for 'StopIteration')
def top_n(n, generator):
    for _ in xrange(n): yield next(generator)

My kubernetes pods keep crashing with "CrashLoopBackOff" but I can't find any log

I observed the same issue, and added the command and args block in yaml file. I am copying sample of my yaml file for reference

 apiVersion: v1
    kind: Pod
    metadata:
      labels:
        run: ubuntu
      name: ubuntu
      namespace: default
    spec:
      containers:
      - image: gcr.io/ow/hellokubernetes/ubuntu
        imagePullPolicy: Never
        name: ubuntu
        resources:
          requests:
            cpu: 100m
        command: ["/bin/sh"]
        args: ["-c", "while true; do echo hello; sleep 10;done"]
      dnsPolicy: ClusterFirst
      enableServiceLinks: true

Why avoid increment ("++") and decrement ("--") operators in JavaScript?

In my experience, ++i or i++ has never caused confusion other than when first learning about how the operator works. It is essential for the most basic for loops and while loops that are taught by any highschool or college course taught in languages where you can use the operator. I personally find doing something like what is below to look and read better than something with a++ being on a separate line.

_x000D_
_x000D_
while ( a < 10 ){_x000D_
    array[a++] = val_x000D_
}
_x000D_
_x000D_
_x000D_

In the end it is a style preference and not anything more, what is more important is that when you do this in your code you stay consistent so that others working on the same code can follow and not have to process the same functionality in different ways.

Also, Crockford seems to use i-=1, which I find to be harder to read than --i or i--

How to run crontab job every week on Sunday

To have a cron executed on Sunday you can use either of these:

5 8 * * 0
5 8 * * 7
5 8 * * Sun

Where 5 8 stands for the time of the day when this will happen: 8:05.

In general, if you want to execute something on Sunday, just make sure the 5th column contains either of 0, 7 or Sun. You had 6, so it was running on Saturday.

The format for cronjobs is:

 +---------------- minute (0 - 59)
 |  +------------- hour (0 - 23)
 |  |  +---------- day of month (1 - 31)
 |  |  |  +------- month (1 - 12)
 |  |  |  |  +---- day of week (0 - 6) (Sunday=0 or 7)
 |  |  |  |  |
 *  *  *  *  *  command to be executed

You can always use crontab.guru as a editor to check your cron expressions.

pythonic way to do something N times without an index variable?

A slightly faster approach than looping on xrange(N) is:

import itertools

for _ in itertools.repeat(None, N):
    do_something()

How to return JSON with ASP.NET & jQuery

This structure works for me - I used it in a small tasks management application.

The controller:

public JsonResult taskCount(string fDate)
{
  // do some stuff based on the date

  // totalTasks is a count of the things I need to do today
  // tasksDone is a count of the tasks I actually did
  // pcDone is the percentage of tasks done

  return Json(new {
    totalTasks = totalTasks,
    tasksDone = tasksDone,
    percentDone = pcDone
  });
}

In the AJAX call I access the data like this:

.done(function (data) {
  // data.totalTasks
  // data.tasksDone
  // data.percentDone
});

regex for zip-code

For the listed three conditions only, these expressions might work also:

^\d{5}[-\s]?(?:\d{4})?$
^\[0-9]{5}[-\s]?(?:[0-9]{4})?$
^\[0-9]{5}[-\s]?(?:\d{4})?$
^\d{5}[-\s]?(?:[0-9]{4})?$

Please see this demo for additional explanation.

If we would have had unexpected additional spaces in between 5 and 4 digits or a continuous 9 digits zip code, such as:

123451234
12345 1234
12345  1234

this expression for instance would be a secondary option with less constraints:

^\d{5}([-]|\s*)?(\d{4})?$

Please see this demo for additional explanation.

RegEx Circuit

jex.im visualizes regular expressions:

enter image description here

Test

_x000D_
_x000D_
const regex = /^\d{5}[-\s]?(?:\d{4})?$/gm;_x000D_
const str = `12345_x000D_
12345-6789_x000D_
12345 1234_x000D_
123451234_x000D_
12345 1234_x000D_
12345  1234_x000D_
1234512341_x000D_
123451`;_x000D_
let m;_x000D_
_x000D_
while ((m = regex.exec(str)) !== null) {_x000D_
    // This is necessary to avoid infinite loops with zero-width matches_x000D_
    if (m.index === regex.lastIndex) {_x000D_
        regex.lastIndex++;_x000D_
    }_x000D_
    _x000D_
    // The result can be accessed through the `m`-variable._x000D_
    m.forEach((match, groupIndex) => {_x000D_
        console.log(`Found match, group ${groupIndex}: ${match}`);_x000D_
    });_x000D_
}
_x000D_
_x000D_
_x000D_

Convert a string to datetime in PowerShell

ParseExact is told the format of the date it is expected to parse, not the format you wish to get out.

$invoice = '01-Jul-16'
[datetime]::parseexact($invoice, 'dd-MMM-yy', $null)

If you then wish to output a date string:

[datetime]::parseexact($invoice, 'dd-MMM-yy', $null).ToString('yyyy-MM-dd')

Chris

Using BufferedReader.readLine() in a while loop properly

Thank you to SLaks and jpm for their help. It was a pretty simple error that I simply did not see.

As SLaks pointed out, br.readLine() was being called twice each loop which made the program only get half of the values. Here is the fixed code:

try{
        InputStream fis=new FileInputStream(targetsFile);
        BufferedReader br=new BufferedReader(new InputStreamReader(fis));
        String words[]=new String[5];
        String line=null;
        while((line=br.readLine())!=null){
            words=line.split(" ");
            int targetX=Integer.parseInt(words[0]);
            int targetY=Integer.parseInt(words[1]);
            int targetW=Integer.parseInt(words[2]);
            int targetH=Integer.parseInt(words[3]);
            int targetHits=Integer.parseInt(words[4]);
            Target a=new Target(targetX, targetY, targetW, targetH, targetHits);
            targets.add(a);
        }
        br.close();
    }
    catch(Exception e){
        System.err.println("Error: Target File Cannot Be Read");
    }

Thanks again! You guys are great!

How to merge a Series and DataFrame

You could construct a dataframe from the series and then merge with the dataframe. So you specify the data as the values but multiply them by the length, set the columns to the index and set params for left_index and right_index to True:

In [27]:

df.merge(pd.DataFrame(data = [s.values] * len(s), columns = s.index), left_index=True, right_index=True)
Out[27]:
   a  b  s1  s2
0  1  3   5   6
1  2  4   5   6

EDIT for the situation where you want the index of your constructed df from the series to use the index of the df then you can do the following:

df.merge(pd.DataFrame(data = [s.values] * len(df), columns = s.index, index=df.index), left_index=True, right_index=True)

This assumes that the indices match the length.

Alter Table Add Column Syntax

This is how Adding new column to Table

ALTER TABLE [tableName]
ADD ColumnName Datatype

E.g

ALTER TABLE [Emp]
ADD Sr_No Int

And If you want to make it auto incremented

ALTER TABLE [Emp]
ADD Sr_No Int IDENTITY(1,1) NOT NULL

Editing in the Chrome debugger

  1. Place a breakpoint
  2. Right click on the breakpoint and select 'Edit breakpoint'
  3. Insert your code. Use SHIFT+ENTER to create a new line.

enter image description here

matplotlib colorbar for scatter

From the matplotlib docs on scatter 1:

cmap is only used if c is an array of floats

So colorlist needs to be a list of floats rather than a list of tuples as you have it now. plt.colorbar() wants a mappable object, like the CircleCollection that plt.scatter() returns. vmin and vmax can then control the limits of your colorbar. Things outside vmin/vmax get the colors of the endpoints.

How does this work for you?

import matplotlib.pyplot as plt
cm = plt.cm.get_cmap('RdYlBu')
xy = range(20)
z = xy
sc = plt.scatter(xy, xy, c=z, vmin=0, vmax=20, s=35, cmap=cm)
plt.colorbar(sc)
plt.show()

Image Example

Checking if a folder exists (and creating folders) in Qt, C++

If you need an empty folder you can loop until you get an empty folder

    QString folder= QString ("%1").arg(QDateTime::currentMSecsSinceEpoch());
    while(QDir(folder).exists())
    {
         folder= QString ("%1").arg(QDateTime::currentMSecsSinceEpoch());
    }
    QDir().mkdir(folder);

This case you will get a folder name with a number .

An invalid XML character (Unicode: 0xc) was found

Today, I've got a similar error:

Servlet.service() for servlet [remoting] in context with path [/***] threw exception [Request processing failed; nested exception is java.lang.RuntimeException: buildDocument failed.] with root cause org.xml.sax.SAXParseException; lineNumber: 19; columnNumber: 91; An invalid XML character (Unicode: 0xc) was found in the value of attribute "text" and element is "label".


After my first encouter with the error, I had re-typed the entire line by hand, so that there was no way for a special character to creep in, and Notepad++ didn't show any non-printable characters (black on white), nevertheless I got the same error over and over.

When I looked up what I've done different than my predecessors, it turned out it was one additional space just before the closing /> (as I've heard was recommended for older parsers, but it shouldn't make any difference anyway, by the XML standards):

<label text="this label's text" layout="cell 0 0, align left" />

When I removed the space:

<label text="this label's text" layout="cell 0 0, align left"/>

everything worked just fine.


So it's definitely a misleading error message.

how to install python distutils

If you are unable to install with either of these:

sudo apt-get install python-distutils
sudo apt-get install python3-distutils

Try this instead:

sudo apt-get install python-distutils-extra

Ref: https://groups.google.com/forum/#!topic/beagleboard/RDlTq8sMxro

Detect if an input has text in it using CSS -- on a page I am visiting and do not control?

There's actually a way to do this without javascript.

If you set an <input>'s required selector to true, you can check if there's text in it with the CSS :valid tag.

References:

MDN Docs
CSS Tricks

_x000D_
_x000D_
input {
  background: red;
}

input:valid {
  background: lightgreen;
}
_x000D_
<input type="text" required>
_x000D_
_x000D_
_x000D_

Coding Conventions - Naming Enums

They're still types, so I always use the same naming conventions I use for classes.

I definitely would frown on putting "Class" or "Enum" in a name. If you have both a FruitClass and a FruitEnum then something else is wrong and you need more descriptive names. I'm trying to think about the kind of code that would lead to needing both, and it seems like there should be a Fruit base class with subtypes instead of an enum. (That's just my own speculation though, you may have a different situation than what I'm imagining.)

The best reference that I can find for naming constants comes from the Variables tutorial:

If the name you choose consists of only one word, spell that word in all lowercase letters. If it consists of more than one word, capitalize the first letter of each subsequent word. The names gearRatio and currentGear are prime examples of this convention. If your variable stores a constant value, such as static final int NUM_GEARS = 6, the convention changes slightly, capitalizing every letter and separating subsequent words with the underscore character. By convention, the underscore character is never used elsewhere.

Getting list of files in documents folder

Apple states about NSSearchPathForDirectoriesInDomains(_:_:_:):

You should consider using the FileManager methods urls(for:in:) and url(for:in:appropriateFor:create:) which return URLs, which are the preferred format.


With Swift 5, FileManager has a method called contentsOfDirectory(at:includingPropertiesForKeys:options:). contentsOfDirectory(at:includingPropertiesForKeys:options:) has the following declaration:

Performs a shallow search of the specified directory and returns URLs for the contained items.

func contentsOfDirectory(at url: URL, includingPropertiesForKeys keys: [URLResourceKey]?, options mask: FileManager.DirectoryEnumerationOptions = []) throws -> [URL]

Therefore, in order to retrieve the urls of the files contained in documents directory, you can use the following code snippet that uses FileManager's urls(for:in:) and contentsOfDirectory(at:includingPropertiesForKeys:options:) methods:

guard let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first else { return }

do {
    let directoryContents = try FileManager.default.contentsOfDirectory(at: documentsDirectory, includingPropertiesForKeys: nil, options: [])

    // Print the urls of the files contained in the documents directory
    print(directoryContents)
} catch {
    print("Could not search for urls of files in documents directory: \(error)")
}

As an example, the UIViewController implementation below shows how to save a file from app bundle to documents directory and how to get the urls of the files saved in documents directory:

import UIKit

class ViewController: UIViewController {

    @IBAction func copyFile(_ sender: UIButton) {
        // Get file url
        guard let fileUrl = Bundle.main.url(forResource: "Movie", withExtension: "mov") else { return }

        // Create a destination url in document directory for file
        guard let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first else { return }
        let documentDirectoryFileUrl = documentsDirectory.appendingPathComponent("Movie.mov")

        // Copy file to document directory
        if !FileManager.default.fileExists(atPath: documentDirectoryFileUrl.path) {
            do {
                try FileManager.default.copyItem(at: fileUrl, to: documentDirectoryFileUrl)
                print("Copy item succeeded")
            } catch {
                print("Could not copy file: \(error)")
            }
        }
    }

    @IBAction func displayUrls(_ sender: UIButton) {
        guard let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first else { return }

        do {
            let directoryContents = try FileManager.default.contentsOfDirectory(at: documentsDirectory, includingPropertiesForKeys: nil, options: [])

            // Print the urls of the files contained in the documents directory
            print(directoryContents) // may print [] or [file:///private/var/mobile/Containers/Data/Application/.../Documents/Movie.mov]
        } catch {
            print("Could not search for urls of files in documents directory: \(error)")
        }
    }

}

Which is better, return value or out parameter?

Additionally, return values are compatible with asynchronous design paradigms.

You cannot designate a function "async" if it uses ref or out parameters.

In summary, Return Values allow method chaining, cleaner syntax (by eliminating the necessity for the caller to declare additional variables), and allow for asynchronous designs without the need for substantial modification in the future.

How to get the hostname of the docker host from inside a docker container on that host without env vars

I ran

docker info | grep Name: | xargs | cut -d' ' -f2

inside my container.

How to find topmost view controller on iOS

For latest Swift Version:
Create a file, name it UIWindowExtension.swift and paste the following snippet:

import UIKit

public extension UIWindow {
    public var visibleViewController: UIViewController? {
        return UIWindow.getVisibleViewControllerFrom(self.rootViewController)
    }

    public static func getVisibleViewControllerFrom(vc: UIViewController?) -> UIViewController? {
        if let nc = vc as? UINavigationController {
            return UIWindow.getVisibleViewControllerFrom(nc.visibleViewController)
        } else if let tc = vc as? UITabBarController {
            return UIWindow.getVisibleViewControllerFrom(tc.selectedViewController)
        } else {
            if let pvc = vc?.presentedViewController {
                return UIWindow.getVisibleViewControllerFrom(pvc)
            } else {
                return vc
            }
        }
    }
}

func getTopViewController() -> UIViewController? {
    let appDelegate = UIApplication.sharedApplication().delegate
    if let window = appDelegate!.window {
        return window?.visibleViewController
    }
    return nil
}

Use it anywhere as:

if let topVC = getTopViewController() {

}

Change language of Visual Studio 2017 RC

I didn't find a complete answer here

Firstly

You should install your preferred language

  1. Open the Visual Studio Installer.
  2. In installed products click on plus Dropdown menu
  3. click edit
  4. then click on language packs
  5. choose you preferred language and finally click on install

Secondly

  1. Go to Tools -> Options

    2.Select International Settings in Environment

    3.click on Menu and select you preferred language

    4.Click on Ok

    5.restart visual studio

How do I pass multiple parameters into a function in PowerShell?

Function Test([string]$arg1, [string]$arg2)
{
    Write-Host "`$arg1 value: $arg1"
    Write-Host "`$arg2 value: $arg2"
}

Test("ABC") ("DEF")

Access to the path denied error in C#

You do not have permissions to access the file. Please be sure whether you can access the file in that drive.

string route= @"E:\Sample.text";
FileStream fs = new FileStream(route, FileMode.Create);

You have to provide the file name to create. Please try this, now you can create.

How can I add a hint text to WPF textbox?

You can do in a very simple way. The idea is to place a Label in the same place as your textbox. Your Label will be visible if textbox has no text and hasn't the focus.

 <Label Name="PalceHolder"  HorizontalAlignment="Left" HorizontalContentAlignment="Center" VerticalContentAlignment="Center" Height="40" VerticalAlignment="Top" Width="239" FontStyle="Italic"  Foreground="BurlyWood">PlaceHolder Text Here
  <Label.Style>
    <Style TargetType="{x:Type Label}">
      <Setter Property="Visibility" Value="Hidden"/>
      <Style.Triggers>
        <MultiDataTrigger>
          <MultiDataTrigger.Conditions>
            <Condition Binding ="{Binding ElementName=PalceHolder, Path=Text.Length}" Value="0"/>
            <Condition Binding ="{Binding ElementName=PalceHolder, Path=IsFocused}" Value="False"/>
          </MultiDataTrigger.Conditions>
          <Setter Property="Visibility" Value="Visible"/>
        </MultiDataTrigger>
      </Style.Triggers>
    </Style>
  </Label.Style>
</Label>
<TextBox  Background="Transparent" Name="TextBox1" HorizontalAlignment="Left" HorizontalContentAlignment="Center" VerticalContentAlignment="Center" Height="40"TextWrapping="Wrap" Text="{Binding InputText,Mode=TwoWay}" VerticalAlignment="Top" Width="239" />

Bonus:If you want to have default value for your textBox, be sure after to set it when submitting data (for example:"InputText"="PlaceHolder Text Here" if empty).

Amazon Linux: apt-get: command not found

There can be 2 issues :=

1. Your are trying the command in machine that does not support apt-get command
because apt-get is suitable for Linux based Ubuntu machines; for MAC, try
apt-get equivalent such as Brew

2. The other issue can be that your installation was not completed properly So

The short answer:

Re-install Ubuntu from a Live CD or USB.

The long version:

The long version would be a waste of your time: your system will never
be clean, but if you insist you could try:

==> Copying everything (missing) except for the /home folder from the Live
CD/USB to your HDD.

OR

==> Do a re-install/repair over the broken system again with the Live
CD / USB stick.

OR

==> Download the deb file for apt-get and install as explained on above posts.
I would definitely go for a fresh new install as there are so many things to
do and so little time.

How to get Map data using JDBCTemplate.queryForMap

queryForMap is appropriate if you want to get a single row. You are selecting without a where clause, so you probably want to queryForList. The error is probably indicative of the fact that queryForMap wants one row, but you query is retrieving many rows.

Check out the docs. There is a queryForList that takes just sql; the return type is a

List<Map<String,Object>>.

So once you have the results, you can do what you are doing. I would do something like

List results = template.queryForList(sql);

for (Map m : results){
   m.get('userid');
   m.get('username');
} 

I'll let you fill in the details, but I would not iterate over keys in this case. I like to explicit about what I am expecting.

If you have a User object, and you actually want to load User instances, you can use the queryForList that takes sql and a class type

queryForList(String sql, Class<T> elementType)

(wow Spring has changed a lot since I left Javaland.)

How to add a border to a widget in Flutter?

Here is an expanded answer. A DecoratedBox is what you need to add a border, but I am using a Container for the convenience of adding margin and padding.

Here is the general setup.

enter image description here

Widget myWidget() {
  return Container(
    margin: const EdgeInsets.all(30.0),
    padding: const EdgeInsets.all(10.0),
    decoration: myBoxDecoration(), //             <--- BoxDecoration here
    child: Text(
      "text",
      style: TextStyle(fontSize: 30.0),
    ),
  );
}

where the BoxDecoration is

BoxDecoration myBoxDecoration() {
  return BoxDecoration(
    border: Border.all(),
  );
}

Border width

enter image description here

These have a border width of 1, 3, and 10 respectively.

BoxDecoration myBoxDecoration() {
  return BoxDecoration(
    border: Border.all(
      width: 1, //                   <--- border width here
    ),
  );
}

Border color

enter image description here

These have a border color of

  • Colors.red
  • Colors.blue
  • Colors.green

Code

BoxDecoration myBoxDecoration() {
  return BoxDecoration(
    border: Border.all(
      color: Colors.red, //                   <--- border color
      width: 5.0,
    ),
  );
}

Border side

enter image description here

These have a border side of

  • left (3.0), top (3.0)
  • bottom (13.0)
  • left (blue[100], 15.0), top (blue[300], 10.0), right (blue[500], 5.0), bottom (blue[800], 3.0)

Code

BoxDecoration myBoxDecoration() {
  return BoxDecoration(
    border: Border(
      left: BorderSide( //                   <--- left side
        color: Colors.black,
        width: 3.0,
      ),
      top: BorderSide( //                    <--- top side
        color: Colors.black,
        width: 3.0,
      ),
    ),
  );
}

Border radius

enter image description here

These have border radii of 5, 10, and 30 respectively.

BoxDecoration myBoxDecoration() {
  return BoxDecoration(
    border: Border.all(
      width: 3.0
    ),
    borderRadius: BorderRadius.all(
        Radius.circular(5.0) //                 <--- border radius here
    ),
  );
}

Going on

DecoratedBox/BoxDecoration are very flexible. Read Flutter — BoxDecoration Cheat Sheet for many more ideas.

java SSL and cert keystore

SSL properties are set at the JVM level via system properties. Meaning you can either set them when you run the program (java -D....) Or you can set them in code by doing System.setProperty.

The specific keys you have to set are below:

javax.net.ssl.keyStore- Location of the Java keystore file containing an application process's own certificate and private key. On Windows, the specified pathname must use forward slashes, /, in place of backslashes.

javax.net.ssl.keyStorePassword - Password to access the private key from the keystore file specified by javax.net.ssl.keyStore. This password is used twice: To unlock the keystore file (store password), and To decrypt the private key stored in the keystore (key password).

javax.net.ssl.trustStore - Location of the Java keystore file containing the collection of CA certificates trusted by this application process (trust store). On Windows, the specified pathname must use forward slashes, /, in place of backslashes, \.

If a trust store location is not specified using this property, the SunJSSE implementation searches for and uses a keystore file in the following locations (in order):

  1. $JAVA_HOME/lib/security/jssecacerts
  2. $JAVA_HOME/lib/security/cacerts

javax.net.ssl.trustStorePassword - Password to unlock the keystore file (store password) specified by javax.net.ssl.trustStore.

javax.net.ssl.trustStoreType - (Optional) For Java keystore file format, this property has the value jks (or JKS). You do not normally specify this property, because its default value is already jks.

javax.net.debug - To switch on logging for the SSL/TLS layer, set this property to ssl.

What is the difference between SAX and DOM?

Here in simpler words:

DOM

  • Tree model parser (Object based) (Tree of nodes).

  • DOM loads the file into the memory and then parse- the file.

  • Has memory constraints since it loads the whole XML file before parsing.

  • DOM is read and write (can insert or delete nodes).

  • If the XML content is small, then prefer DOM parser.

  • Backward and forward search is possible for searching the tags and evaluation of the information inside the tags. So this gives the ease of navigation.

  • Slower at run time.

SAX

  • Event based parser (Sequence of events).

  • SAX parses the file as it reads it, i.e. parses node by node.

  • No memory constraints as it does not store the XML content in the memory.

  • SAX is read only i.e. can’t insert or delete the node.

  • Use SAX parser when memory content is large.

  • SAX reads the XML file from top to bottom and backward navigation is not possible.

  • Faster at run time.

Find the paths between two given nodes?

Dijkstra's algorithm applies more to weighted paths and it sounds like the poster was wanting to find all paths, not just the shortest.

For this application, I'd build a graph (your application sounds like it wouldn't need to be directed) and use your favorite search method. It sounds like you want all paths, not just a guess at the shortest one, so use a simple recursive algorithm of your choice.

The only problem with this is if the graph can be cyclic.

With the connections:

  • 1, 2
  • 1, 3
  • 2, 3
  • 2, 4

While looking for a path from 1->4, you could have a cycle of 1 -> 2 -> 3 -> 1.

In that case, then I'd keep a stack as traversing the nodes. Here's a list with the steps for that graph and the resulting stack (sorry for the formatting - no table option):

current node (possible next nodes minus where we came from) [stack]

  1. 1 (2, 3) [1]
  2. 2 (3, 4) [1, 2]
  3. 3 (1) [1, 2, 3]
  4. 1 (2, 3) [1, 2, 3, 1] //error - duplicate number on the stack - cycle detected
  5. 3 () [1, 2, 3] // back-stepped to node three and popped 1 off the stack. No more nodes to explore from here
  6. 2 (4) [1, 2] // back-stepped to node 2 and popped 1 off the stack.
  7. 4 () [1, 2, 4] // Target node found - record stack for a path. No more nodes to explore from here
  8. 2 () [1, 2] //back-stepped to node 2 and popped 4 off the stack. No more nodes to explore from here
  9. 1 (3) [1] //back-stepped to node 1 and popped 2 off the stack.
  10. 3 (2) [1, 3]
  11. 2 (1, 4) [1, 3, 2]
  12. 1 (2, 3) [1, 3, 2, 1] //error - duplicate number on the stack - cycle detected
  13. 2 (4) [1, 3, 2] //back-stepped to node 2 and popped 1 off the stack
  14. 4 () [1, 3, 2, 4] Target node found - record stack for a path. No more nodes to explore from here
  15. 2 () [1, 3, 2] //back-stepped to node 2 and popped 4 off the stack. No more nodes
  16. 3 () [1, 3] // back-stepped to node 3 and popped 2 off the stack. No more nodes
  17. 1 () [1] // back-stepped to node 1 and popped 3 off the stack. No more nodes
  18. Done with 2 recorded paths of [1, 2, 4] and [1, 3, 2, 4]

Get ASCII value at input word

There is a major gotcha associated with getting an ASCII code of a char value.

In the proper sense, it can't be done.

It's because char has a range of 65535 whereas ASCII is restricted to 128. There is a huge amount of characters that have no ASCII representation at all.

The proper way would be to use a Unicode code point which is the standard numerical equivalent of a character in the Java universe.

Thankfully, Unicode is a complete superset of ASCII. That means Unicode numbers for Latin characters are equal to their ASCII counterparts. For example, A in Unicode is U+0041 or 65 in decimal. In contrast, ASCII has no mapping for 99% of char-s. Long story short:

char ch = 'A';
int cp = String.valueOf(ch).codePointAt(0);

Furthermore, a 16-bit primitive char actually represents a code unit, not a character and is thus restricted to Basic Multilingual Plane, for historical reasons. Entities beyond it require Character objects which deal away with the fixed bit-length limitation.

Get month and year from date cells Excel

You could right click on those cells, go to format, select custom, then type mm yyyy.

SQL query for a carriage return in a string and ultimately removing carriage return

this works: select * from table where column like '%(hit enter)%'

Ignore the brackets and hit enter to introduce new line.

Converting Date and Time To Unix Timestamp

Seems like getTime is not function on above answer.

Date.parse(currentDate)/1000

How to add a column in TSQL after a specific column?

In Microsoft SQL Server Management Studio (the admin tool for MSSQL) just go into "design" on a table and drag the column to the new position. Not command line but you can do it.

Array and string offset access syntax with curly braces is deprecated

It's really simple to fix the issue, however keep in mind that you should fork and commit your changes for each library you are using in their repositories to help others as well.

Let's say you have something like this in your code:

$str = "test";
echo($str{0});

since PHP 7.4 curly braces method to get individual characters inside a string has been deprecated, so change the above syntax into this:

$str = "test";
echo($str[0]);

Fixing the code in the question will look something like this:

public function getRecordID(string $zoneID, string $type = '', string $name = ''): string
{
    $records = $this->listRecords($zoneID, $type, $name);
    if (isset($records->result[0]->id)) {
        return $records->result[0]->id;
    }
    return false;
}

Detecting arrow key presses in JavaScript

If you want to detect arrow keypresses but not need specific in Javascript

function checkKey(e) {
   if (e.keyCode !== 38 || e.keyCode !== 40 || e.keyCode !== 37 || e.keyCode !== 39){
    // do something
   };
}

Convert JSON to Map

Try this code:

  public static Map<String, Object> convertJsonIntoMap(String jsonFile) {
        Map<String, Object> map = new HashMap<>();
        try {
            ObjectMapper mapper = new ObjectMapper();
            mapper.configure(DeserializationFeature.UNWRAP_ROOT_VALUE, true);
            mapper.readValue(jsonFile, new TypeReference<Map<String, Object>>() {
            });
            map = mapper.readValue(jsonFile, new TypeReference<Map<String, String>>() {
            });
        } catch (IOException e) {
            e.printStackTrace();
        }
        return map;
    }

C++ - Hold the console window open?

I use std::getwchar() in my environment which is with mingw32 - gcc-4.6.2 compiler, Here is a sample code.

#include <iostream>
#include "Arithmetics.h"

using namespace std;

int main() {
    ARITHMETICS_H::testPriorities();

    cout << "Press any key to exit." << endl;
    getwchar();
    return 0;
}

How to submit http form using C#

Your HTML file is not going to interact with C# directly, but you can write some C# to behave as if it were the HTML file.

For example: there is a class called System.Net.WebClient with simple methods:

using System.Net;
using System.Collections.Specialized;

...
using(WebClient client = new WebClient()) {

    NameValueCollection vals = new NameValueCollection();
    vals.Add("test", "test string");
    client.UploadValues("http://www.someurl.com/page.php", vals);
}

For more documentation and features, refer to the MSDN page.

How to use adb command to push a file on device without sd card

Certain versions of android do not fire proper tasks for updating the state of file system. You could trigger an explicit intent for updating the status of the file system. (I just tested after being in the same OP's situation)

adb shell am broadcast -a android.intent.action.MEDIA_MOUNTED -d file:///

(You could pass a specific filepath instead of file:/// like file:///sdcard )

Best way to incorporate Volley (or other library) into Android Studio project

Nowadays

dependencies {
    compile 'com.android.volley:volley:1.0.0'
}   

A lot of different ways to do it back in the day (original answer)

  • Use the source files from git (a rather manual/general way described here)

    1. Download / install the git client (if you don't have it on your system yet): http://git-scm.com/downloads (or via git clone https://github.com/git/git ... sry bad one, but couldn't resist ^^)
    2. Execute git clone https://android.googlesource.com/platform/frameworks/volley
    3. Copy the com folder from within [path_where_you_typed_git_clone]/volley/src to your projects app/src/main/java folder (Integrate it instead, if you already have a com folder there!! ;-))

    The files show up immediately in Android Studio. For Eclipse you will have to right-click on the src folder and press refresh (or F5) first.

  • Use gradle via the "unofficial" maven mirror

    1. In your project's src/build.gradle file add following volley dependency:

      dependencies {
          compile fileTree(dir: 'libs', include: ['*.jar'])
          // ...
      
          compile 'com.mcxiaoke.volley:library:1.+'
      }
      
    2. Click on Try Again which should right away appear on the top of the file, or just Build it if not

    The main "advantage" here is, that this will keep the version up to date for you, whereas in the other two cases you would have to manually update volley.

    On the "downside" it is not officially from google, but a third party weekly mirror.

    But both of these points, are really relative to what you would need/want. Also if you don't want updates, just put the desired version there instead e.g. compile 'com.mcxiaoke.volley:library:1.0.7'.

jQuery - determine if input element is textbox or select list

If you just want to check the type, you can use jQuery's .is() function,

Like in my case I used below,

if($("#id").is("select")) {
 alert('Select'); 
else if($("#id").is("input")) {
 alert("input");
}

git stash apply version

If one is on a Windows machine and in PowerShell, one needs to quote the argument such as:

git stash apply "stash@{0}"

...or to apply the changes and remove from the stash:

git stash pop "stash@{0}"

Otherwise without the quotes you might get this error:

fatal: ambiguous argument 'stash@': unknown revision or path not in the working tree.

Using PHP Replace SPACES in URLS with %20

Use urlencode() rather than trying to implement your own. Be lazy.

Replace all whitespace with a line break/paragraph mark to make a word list

All of the examples listed above for sed break on one platform or another. None of them work with the version of sed shipped on Macs.

However, Perl's regex works the same on any machine with Perl installed:

perl -pe 's/\s+/\n/g' file.txt

If you want to save the output:

perl -pe 's/\s+/\n/g' file.txt > newfile.txt

If you want only unique occurrences of words:

perl -pe 's/\s+/\n/g' file.txt | sort -u > newfile.txt

Wait until all jQuery Ajax requests are done?

If you need something simple; once and done callback

        //multiple ajax calls above
        var callback = function () {
            if ($.active !== 0) {
                setTimeout(callback, '500');
                return;
            }
            //whatever you need to do here
            //...
        };
        callback();

How to quickly drop a user with existing privileges

Also note, if you have explicitly granted:

CONNECT ON DATABASE xxx TO GROUP ,

you will need to revoke this separately from DROP OWNED BY, using:

REVOKE CONNECT ON DATABASE xxx FROM GROUP

Java: how to represent graphs?

Time ago I had the same problem and did my own implementation. What I suggest you is to implement another class: Edge. Then, a Vertex will have a List of Edge.

public class Edge {
    private Node a, b;
    private directionEnum direction;     // AB, BA or both
    private int weight;
    ...
}

It worked for me. But maybe is so simple. There is this library that maybe can help you if you look into its code: http://jgrapht.sourceforge.net/

SSH Key - Still asking for password and passphrase

If you're using windows, this worked for me:

eval `ssh-agent -s`
ssh-add ~/.ssh/*_rsa

It'll ask for passphrase in the second command, and that's it.

Using putty to scp from windows to Linux

You can use PSCP to copy files from Windows to Linux.

  1. Download PSCP from putty.org
  2. Open cmd in the directory with pscp.exe file
  3. Type command pscp source_file user@host:destination_file

Reference

Integer value in TextView

It might be cleaner for some people to work with an Integer object so you can just call toString() directly on the object:

Integer length = my_text_view.getText().getLength();
counter_text_view.setText( length.toString() );

LoDash: Get an array of values from an array of object properties

If you are using native javascript then you can use this code -

let ids = users.map(function(obj, index) {

    return obj.id;
})

console.log(ids); //[12, 14, 16, 18]

Howto? Parameters and LIKE statement SQL

you have to do:

LIKE '%' + @param + '%'

HTML embed autoplay="false", but still plays automatically

<video width="320" height="240" controls autoplay>
<source src="movie.mp4" type="video/mp4"> Your browser does not support the video tag.
</video>

Remove autoplay if you want to disable auto playing video.

Including a groovy script in another groovy

A combination of @grahamparks and @snowindy answers with a couple of modifications is what worked for my Groovy scripts running on Tomcat:

Utils.groovy

class Utils {
    def doSth() {...}
}

MyScript.groovy:

/* import Utils --> This import does not work. The class is not even defined at this time */
Class groovyClass = new GroovyClassLoader(getClass().getClassLoader()).parseClass(new File("full_path_to/Utils.groovy")); // Otherwise it assumes current dir is $CATALINA_HOME
def foo = groovyClass.newInstance(); // 'def' solves compile time errors!!
foo.doSth(); // Actually works!

SSL certificate is not trusted - on mobile only

Put your domain name here: https://www.ssllabs.com/ssltest/analyze.html You should be able to see if there are any issues with your ssl certificate chain. I am guessing that you have SSL chain issues. A short description of the problem is that there's actually a list of certificates on your server (and not only one) and these need to be in the correct order. If they are there but not in the correct order, the website will be fine on desktop browsers (an iOs as well I think), but android is more strict about the order of certificates, and will give an error if the order is incorrect. To fix this you just need to re-order the certificates.

How to lock orientation of one view controller to portrait mode only in Swift

Create new extension with

import UIKit

extension UINavigationController {
    override open var supportedInterfaceOrientations: UIInterfaceOrientationMask {
        return .portrait
    }
}

extension UITabBarController {
    override open var supportedInterfaceOrientations: UIInterfaceOrientationMask {
        return .portrait
    }
}

How can I assign the output of a function to a variable using bash?

You may use bash functions in commands/pipelines as you would otherwise use regular programs. The functions are also available to subshells and transitively, Command Substitution:

VAR=$(scan)

Is the straighforward way to achieve the result you want in most cases. I will outline special cases below.

Preserving trailing Newlines:

One of the (usually helpful) side effects of Command Substitution is that it will strip any number of trailing newlines. If one wishes to preserve trailing newlines, one can append a dummy character to output of the subshell, and subsequently strip it with parameter expansion.

function scan2 () {
    local nl=$'\x0a';  # that's just \n
    echo "output${nl}${nl}" # 2 in the string + 1 by echo
}

# append a character to the total output.
# and strip it with %% parameter expansion.
VAR=$(scan2; echo "x"); VAR="${VAR%%x}"

echo "${VAR}---"

prints (3 newlines kept):

output


---

Use an output parameter: avoiding the subshell (and preserving newlines)

If what the function tries to achieve is to "return" a string into a variable , with bash v4.3 and up, one can use what's called a nameref. Namerefs allows a function to take the name of one or more variables output parameters. You can assign things to a nameref variable, and it is as if you changed the variable it 'points to/references'.

function scan3() {
    local -n outvar=$1    # -n makes it a nameref.
    local nl=$'\x0a'
    outvar="output${nl}${nl}"  # two total. quotes preserve newlines
}

VAR="some prior value which will get overwritten"

# you pass the name of the variable. VAR will be modified.
scan3 VAR

# newlines are also preserved.
echo "${VAR}==="

prints:

output

===

This form has a few advantages. Namely, it allows your function to modify the environment of the caller without using global variables everywhere.

Note: using namerefs can improve the performance of your program greatly if your functions rely heavily on bash builtins, because it avoids the creation of a subshell that is thrown away just after. This generally makes more sense for small functions reused often, e.g. functions ending in echo "$returnstring"

This is relevant. https://stackoverflow.com/a/38997681/5556676

lists and arrays in VBA

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

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

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

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

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

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

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

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

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

Edit:

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

    subject = "Example"
    counter = Len(subject)

    ReDim TestArray(1 To counter) As String

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

Android ImageView's onClickListener does not work

Had the same problem, thanks for the Framelayout tip! I was using two overlapped images in a framelayout (the one at top was an alpha mask, to give the effect of soft borders)

I set in the xml android:clickable="true" for the image I wanted to launch the onClickListener, and android:clickable="false" to the alpha mask.

How to make background of table cell transparent

What is this? :)

background-color: #D8F0DA;

Try

 background: none

And override works only if property is exactly the same.

background doesn't override background-color.

If you want alpha transparency, then use something like this

background: rgba(100, 100, 100, 0.5);

Failed to execute removeChild on Node

I was wraped it with <> </> as a parent when I changed it to normal , div , its worked fine

How to run a shell script on a Unix console or Mac terminal?

If you want the script to run in the current shell (e.g. you want it to be able to affect your directory or environment) you should say:

. /path/to/script.sh

or

source /path/to/script.sh

Note that /path/to/script.sh can be relative, for instance . bin/script.sh runs the script.sh in the bin directory under the current directory.

Why are Python lambdas useful?

As stated above, the lambda operator in Python defines an anonymous function, and in Python functions are closures. It is important not to confuse the concept of closures with the operator lambda, which is merely syntactic methadone for them.

When I started in Python a few years ago, I used lambdas a lot, thinking they were cool, along with list comprehensions. However, I wrote and have to maintain a big website written in Python, with on the order of several thousand function points. I've learnt from experience that lambdas might be OK to prototype things with, but offer nothing over inline functions (named closures) except for saving a few key-stokes, or sometimes not.

Basically this boils down to several points:

  • it is easier to read software that is explicitly written using meaningful names. Anonymous closures by definition cannot have a meaningful name, as they have no name. This brevity seems, for some reason, to also infect lambda parameters, hence we often see examples like lambda x: x+1
  • it is easier to reuse named closures, as they can be referred to by name more than once, when there is a name to refer to them by.
  • it is easier to debug code that is using named closures instead of lambdas, because the name will appear in tracebacks, and around the error.

That's enough reason to round them up and convert them to named closures. However, I hold two other grudges against anonymous closures.

The first grudge is simply that they are just another unnecessary keyword cluttering up the language.

The second grudge is deeper and on the paradigm level, i.e. I do not like that they promote a functional-programming style, because that style is less flexible than the message passing, object oriented or procedural styles, because the lambda calculus is not Turing-complete (luckily in Python, we can still break out of that restriction even inside a lambda). The reasons I feel lambdas promote this style are:

  • There is an implicit return, i.e. they seem like they 'should' be functions.

  • They are an alternative state-hiding mechanism to another, more explicit, more readable, more reusable and more general mechanism: methods.

I try hard to write lambda-free Python, and remove lambdas on sight. I think Python would be a slightly better language without lambdas, but that's just my opinion.

Remove specific characters from a string in Python

Using filter, you'd just need one line

line = filter(lambda char: char not in " ?.!/;:", line)

This treats the string as an iterable and checks every character if the lambda returns True:

>>> help(filter)
Help on built-in function filter in module __builtin__:

filter(...)
    filter(function or None, sequence) -> list, tuple, or string

    Return those items of sequence for which function(item) is true.  If
    function is None, return the items that are true.  If sequence is a tuple
    or string, return the same type, else return a list.

Jmeter - get current date and time

Use this format: ${__time(yyyy-MM-dd'T'hh:mm:ss.SS'Z')}

Which will give you: 2018-01-16T08:32:28.75Z

how to add values to an array of objects dynamically in javascript?

In Year 2019, we can use Javascript's ES6 Spread syntax to do it concisely and efficiently

data = [...data, {"label": 2, "value": 13}]

Examples

_x000D_
_x000D_
var data = [_x000D_
      {"label" : "1", "value" : 12},_x000D_
      {"label" : "1", "value" : 12},_x000D_
      {"label" : "1", "value" : 12},_x000D_
    ];_x000D_
    _x000D_
data = [...data, {"label" : "2", "value" : 14}] _x000D_
console.log(data)
_x000D_
_x000D_
_x000D_

For your case (i know it was in 2011), we can do it with map() & forEach() like below

_x000D_
_x000D_
var lab = ["1","2","3","4"];_x000D_
var val = [42,55,51,22];_x000D_
_x000D_
//Using forEach()_x000D_
var data = [];_x000D_
val.forEach((v,i) => _x000D_
   data= [...data, {"label": lab[i], "value":v}]_x000D_
)_x000D_
_x000D_
//Using map()_x000D_
var dataMap = val.map((v,i) => _x000D_
 ({"label": lab[i], "value":v})_x000D_
)_x000D_
_x000D_
console.log('data: ', data);_x000D_
console.log('dataMap : ', dataMap);
_x000D_
_x000D_
_x000D_

What is the maximum possible length of a .NET string?

Since the Length property of System.String is an Int32, I would guess that that the maximum length would be 2,147,483,647 chars (max Int32 size). If it allowed longer you couldn't check the Length since that would fail.

How to add 30 minutes to a JavaScript Date object?

Just another option, which I wrote:

DP_DateExtensions Library

It's overkill if this is all the date processing that you need, but it will do what you want.

Supports date/time formatting, date math (add/subtract date parts), date compare, date parsing, etc. It's liberally open sourced.

Custom Date/Time formatting in SQL Server

Yes Depart is a solution for that but I think this kind of methods are long trips!

SQL SERVER:

SELECT CAST(DATEPART(DD,GETDATE()) AS VARCHAR)+'/'
+CAST(DATEPART(MM,GETDATE()) AS VARCHAR)
+'/'+CAST(DATEPART(YYYY,GETDATE()) AS VARCHAR)
+' '+CAST(DATEPART(HH,GETDATE()) AS VARCHAR)
+':'+CAST(DATEPART(MI,GETDATE()) AS VARCHAR)

Oracle:

Select to_char(sysdate,'DD/MM/YYYY HH24:MI') from dual

You may write your own function by this way you can get rid of this mess;

http://sql.dzone.com/news/custom-date-formatting-sql-ser

select myshortfun(getdate(),myformat)
GO

Switching to landscape mode in Android Emulator

for windows try left Ctrl key with F11 or F12 or Num off 7

Where is a log file with logs from a container?

A container's logs can be found in :

/var/lib/docker/containers/<container id>/<container id>-json.log

(if you use the default log format which is json)

How can I get a count of the total number of digits in a number?

static void Main(string[] args)
{
    long blah = 20948230498204;
    Console.WriteLine(blah.ToString().Length);
}

MySQL update CASE WHEN/THEN/ELSE

Try this

UPDATE `table` SET `uid` = CASE
    WHEN id = 1 THEN 2952
    WHEN id = 2 THEN 4925
    WHEN id = 3 THEN 1592
    ELSE `uid`
    END
WHERE id  in (1,2,3)

Using PowerShell credentials without being prompted for a password

Here are two ways you could do this, if you are scheduling the reboot.

First you could create a task on one machine using credentials that have rights needed to connect and reboot another machine. This makes the scheduler responsible for securely storing the credentials. The reboot command (I'm a Powershell guy, but this is cleaner.) is:

SHUTDOWN /r /f /m \\ComputerName

The command line to create a scheduled task on the local machine, to remotely reboot another, would be:

SCHTASKS /Create /TN "Reboot Server" /TR "shutdown.exe /r /f /m \\ComputerName" /SC ONCE /ST 00:00 /SD "12/24/2012" /RU "domain\username" /RP "password"

I prefer the second way, where you use your current credentials to create a scheduled task that runs with the system account on a remote machine.

SCHTASKS /Create /TN "Reboot Server" /TR "shutdown.exe /r /f" /SC ONCE /ST 00:00 /SD "12/24/2012" /RU SYSTEM /S ComputerName

This also works through the GUI, just enter SYSTEM as the user name, leaving the password fields blank.

Iterating through a list in reverse order in java

Reason : "Don't know why there is no descendingIterator with ArrayList..."

Since array list doesnot keep the list in the same order as data has been added to list. So, never use Arraylist .

Linked list will keep the data in same order of ADD to list.

So , above in my example, i used ArrayList() in order to make user to twist their mind and make them to workout something from their side.

Instead of this

List<String> list = new ArrayList<String>();

USE:

List<String> list = new LinkedList<String>();

list.add("ravi");

list.add("kant");

list.add("soni");

// Iterate to disply : result will be as ---     ravi kant soni

for (String name : list) {
  ...
}

//Now call this method

Collections.reverse(list);

// iterate and print index wise : result will be as ---     soni kant ravi

for (String name : list) {
  ...
}

Builder Pattern in Effective Java

As many already stated here you need to make the class static. Just small addition - if you want, there is a bit different way without static one.

Consider this. Implementing a builder by declaring something like withProperty(value) type setters inside the class and make them return a reference to itself. In this approach, you have a single and an elegant class which is a thread safe and concise.

Consider this:

public class DataObject {

    private String first;
    private String second;
    private String third;

    public String getFirst(){
       return first; 
    }

    public void setFirst(String first){
       this.first = first; 
    }

    ... 

    public DataObject withFirst(String first){
       this.first = first;
       return this; 
    }

    public DataObject withSecond(String second){
       this.second = second;
       return this; 
    }

    public DataObject withThird(String third){
       this.third = third;
       return this; 
    }
}


DataObject dataObject = new DataObject()
     .withFirst("first data")
     .withSecond("second data")
     .withThird("third data");

Check it out for more Java Builder examples.

jQuery Mobile how to check if button is disabled?

Use .prop instead:

$('#deliveryNext').prop('disabled')

How can I get the console logs from the iOS Simulator?

In Xcode: View->Debug Area->Activate Console

enter image description here

How to transfer some data to another Fragment?

If you are using graph for navigation between fragments you can do this: From fragment A:

    Bundle bundle = new Bundle();
    bundle.putSerializable(KEY, yourObject);
    Navigation.findNavController(view).navigate(R.id.fragment, bundle);

To fragment B:

    Bundle bundle = getArguments();
    object = (Object) bundle.getSerializable(KEY);

Of course your object must implement Serializable

Flatten an irregular list of lists

This will flatten a list or dictionary (or list of lists or dictionaries of dictionaries etc). It assumes that the values are strings and it creates a string that concatenates each item with a separator argument. If you wanted you could use the separator to split the result into a list object afterward. It uses recursion if the next value is a list or a string. Use the key argument to tell whether you want the keys or the values (set key to false) from the dictionary object.

def flatten_obj(n_obj, key=True, my_sep=''):
    my_string = ''
    if type(n_obj) == list:
        for val in n_obj:
            my_sep_setter = my_sep if my_string != '' else ''
            if type(val) == list or type(val) == dict:
                my_string += my_sep_setter + flatten_obj(val, key, my_sep)
            else:
                my_string += my_sep_setter + val
    elif type(n_obj) == dict:
        for k, v in n_obj.items():
            my_sep_setter = my_sep if my_string != '' else ''
            d_val = k if key else v
            if type(v) == list or type(v) == dict:
                my_string += my_sep_setter + flatten_obj(v, key, my_sep)
            else:
                my_string += my_sep_setter + d_val
    elif type(n_obj) == str:
        my_sep_setter = my_sep if my_string != '' else ''
        my_string += my_sep_setter + n_obj
        return my_string
    return my_string

print(flatten_obj(['just', 'a', ['test', 'to', 'try'], 'right', 'now', ['or', 'later', 'today'],
                [{'dictionary_test': 'test'}, {'dictionary_test_two': 'later_today'}, 'my power is 9000']], my_sep=', ')

yields:

just, a, test, to, try, right, now, or, later, today, dictionary_test, dictionary_test_two, my power is 9000

How do I get elapsed time in milliseconds in Ruby?

To get time in milliseconds, it's better to add .round(3), so it will be more accurate in some cases:

puts Time.now.to_f # => 1453402722.577573

(Time.now.to_f.round(3)*1000).to_i  # => 1453402722578

How to fix "Attempted relative import in non-package" even with __init__.py

You can use import components.core directly if you append the current directory to sys.path:

if __name__ == '__main__' and __package__ is None:
    from os import sys, path
    sys.path.append(path.dirname(path.dirname(path.abspath(__file__))))

SQL: Select columns with NULL values only

You can do:

select 
  count(<columnName>)
from
  <tableName>

If the count returns 0 that means that all rows in that column all NULL (or there is no rows at all in the table)

can be changed to

select 
    case(count(<columnName>)) when 0 then 'Nulls Only' else 'Some Values' end
from 
    <tableName>

If you want to automate it you can use system tables to iterate the column names in the table you are interested in

Simple tool to 'accept theirs' or 'accept mine' on a whole file using git

Try this:

To accept theirs changes: git merge --strategy-option theirs

To accept yours: git merge --strategy-option ours

Git fails when pushing commit to github

I tried to push to my own hosted bonobo-git server, and did not realise, that the http.postbuffer meant the project directory ...

so just for other confused ones:

why? In my case, I had large zip files with assets and some PSDs pushed as well - to big for the buffer I guess.

How to do this http.postbuffer: execute that command within your project src directory, next to the .git folder, not on the server.

be aware, large temp (chunk) files will be created of that buffer size.

Note: Just check your largest files, then set the buffer.

Delete with "Join" in Oracle sql Query

Recently I learned of the following syntax:

DELETE (SELECT *
        FROM productfilters pf
        INNER JOIN product pr
            ON pf.productid = pr.id
        WHERE pf.id >= 200
            AND pr.NAME = 'MARK')

I think it looks much cleaner then other proposed code.

Can you disable tabs in Bootstrap?

You can disable a tab in bootstrap 4 by adding class disabled to the child of nav-item as follows

<li class="nav-item">
    <a class="nav-link disabled" data-toggle="tab" href="#messages7" role="tab" aria-expanded="false">
        <i class="icofont icofont-ui-message"></i>Home</a>
    <div class="slide"></div>
</li>

dd: How to calculate optimal blocksize?

This is totally system dependent. You should experiment to find the optimum solution. Try starting with bs=8388608. (As Hitachi HDDs seems to have 8MB cache.)

Export pictures from excel file into jpg using VBA

This code:

Option Explicit

Sub ExportMyPicture()

     Dim MyChart As String, MyPicture As String
     Dim PicWidth As Long, PicHeight As Long

     Application.ScreenUpdating = False
     On Error GoTo Finish

     MyPicture = Selection.Name
     With Selection
           PicHeight = .ShapeRange.Height
           PicWidth = .ShapeRange.Width
     End With

     Charts.Add
     ActiveChart.Location Where:=xlLocationAsObject, Name:="Sheet1"
     Selection.Border.LineStyle = 0
     MyChart = Selection.Name & " " & Split(ActiveChart.Name, " ")(2)

     With ActiveSheet
           With .Shapes(MyChart)
                 .Width = PicWidth
                 .Height = PicHeight
           End With

           .Shapes(MyPicture).Copy

           With ActiveChart
                 .ChartArea.Select
                 .Paste
           End With

           .ChartObjects(1).Chart.Export Filename:="MyPic.jpg", FilterName:="jpg"
           .Shapes(MyChart).Cut
     End With

     Application.ScreenUpdating = True
     Exit Sub

Finish:
     MsgBox "You must select a picture"
End Sub

was copied directly from here, and works beautifully for the cases I tested.

How to post data using HttpClient?

You need to use:

await client.PostAsync(uri, content);

Something like that:

var comment = "hello world";
var questionId = 1;

var formContent = new FormUrlEncodedContent(new[]
{
    new KeyValuePair<string, string>("comment", comment), 
    new KeyValuePair<string, string>("questionId", questionId) 
});

var myHttpClient = new HttpClient();
var response = await myHttpClient.PostAsync(uri.ToString(), formContent);

And if you need to get the response after post, you should use:

var stringContent = await response.Content.ReadAsStringAsync();

Hope it helps ;)

What is the minimum length of a valid international phone number?

EDIT 2015-06-27: Minimum is actually 8, including country code. My bad.

Original post

The minimum phone number that I use is 10 digits. International users should always be putting their country code, and as far as I know there are no countries with fewer than ten digits if you count country code.

More info here: https://en.wikipedia.org/wiki/Telephone_numbering_plan

Python PDF library

There is also http://appyframework.org/pod.html which takes a LibreOffice or OpenOffice document as template and can generate pdf, rtf, odt ... To generate pdf it requires a headless OOo on some server. Documentation is concise but relatively complete. http://appyframework.org/podWritingTemplates.html If you need advice, the author is rather helpful.

Compare dates with javascript

The best way is,

var first = '2012-11-21';
var second = '2012-11-03';

if (new Date(first) > new Date(second) {
    .....
}

Sort arrays of primitive types in descending order

Your algorithm is correct. But we can do optimization as follows: While reversing, You may try keeping another variable to reduce backward counter since computing of array.length-(i+1) may take time! And also move declaration of temp outside so that everytime it needs not to be allocated

double temp;

for(int i=0,j=array.length-1; i < (array.length/2); i++, j--) {

     // swap the elements
     temp = array[i];
     array[i] = array[j];
     array[j] = temp;
}

Where to declare variable in react js

Assuming that onMove is an event handler, it is likely that its context is something other than the instance of MyContainer, i.e. this points to something different.

You can manually bind the context of the function during the construction of the instance via Function.bind:

class MyContainer extends Component {
  constructor(props) {
    super(props);

    this.onMove = this.onMove.bind(this);

    this.test = "this is a test";
  }

  onMove() {
    console.log(this.test);
  }
}

Also, test !== testVariable.

How to find the lowest common ancestor of two nodes in any binary tree?

Starting from root node and moving downwards if you find any node that has either p or q as its direct child then it is the LCA. (edit - this should be if p or q is the node's value, return it. Otherwise it will fail when one of p or q is a direct child of the other.)

Else if you find a node with p in its right(or left) subtree and q in its left(or right) subtree then it is the LCA.

The fixed code looks like:

treeNodePtr findLCA(treeNodePtr root, treeNodePtr p, treeNodePtr q) {

        // no root no LCA.
        if(!root) {
                return NULL;
        }

        // if either p or q is the root then root is LCA.
        if(root==p || root==q) {
                return root;
        } else {
                // get LCA of p and q in left subtree.
                treeNodePtr l=findLCA(root->left , p , q);

                // get LCA of p and q in right subtree.
                treeNodePtr r=findLCA(root->right , p, q);

                // if one of p or q is in leftsubtree and other is in right
                // then root it the LCA.
                if(l && r) {
                        return root;
                }
                // else if l is not null, l is LCA.
                else if(l) {
                        return l;
                } else {
                        return r;
                }
        }
}

The below code fails when either is the direct child of other.

treeNodePtr findLCA(treeNodePtr root, treeNodePtr p, treeNodePtr q) {

        // no root no LCA.
        if(!root) {
                return NULL;
        }

        // if either p or q is direct child of root then root is LCA.
        if(root->left==p || root->left==q || 
           root->right ==p || root->right ==q) {
                return root;
        } else {
                // get LCA of p and q in left subtree.
                treeNodePtr l=findLCA(root->left , p , q);

                // get LCA of p and q in right subtree.
                treeNodePtr r=findLCA(root->right , p, q);

                // if one of p or q is in leftsubtree and other is in right
                // then root it the LCA.
                if(l && r) {
                        return root;
                }
                // else if l is not null, l is LCA.
                else if(l) {
                        return l;
                } else {
                        return r;
                }
        }
}

Code In Action

Change language for bootstrap DateTimePicker

you need to add the javascript language file,after the moment library, example:

<script type="text/javascript" src="js/moment/moment.js"></script>
<script type="text/javascript" src="js/moment/es.js"></script>

now you can set a language.

<script type="text/javascript">
$(function () {
  $('#datetimepicker1').datetimepicker({locale:'es'});
});
</script>

Here are all language: https://github.com/moment/moment

Use :hover to modify the css of another class?

Provided .wrapper is inside .item, and provided you're either not in IE 6 or .item is an a tag, the CSS you have should work just fine. Do you have evidence to suggest it isn't?

EDIT:

CSS alone can't affect something not contained within it. To make this happen, format your menu like so:

<ul class="menu">
    <li class="menuitem">
        <a href="destination">menu text</a>
        <ul class="menu">
            <li class="menuitem">
                <a href="destination">part of pull-out menu</a>
... etc ...

and your CSS like this:

.menu .menu {
    display: none;
}

.menu .menuitem:hover .menu {
    display: block;
    float: left;
    // likely need to set top & left
}

Java Hashmap: How to get key from value?

It sounds like the best way is for you to iterate over entries using map.entrySet() since map.containsValue() probably does this anyway.