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Which equals operator (== vs ===) should be used in JavaScript comparisons?

...n the third rule) Now it becomes interesting: var a = "12" + "3"; var b = "123"; alert(a === b); // returns true, because strings behave like value types But how about this?: var a = new String("123"); var b = "123"; alert(a === b); // returns false !! (but they are equal and of the same type) I...
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Summarizing multiple columns with dplyr? [duplicate]

...brary(dplyr) library(purrrlyr) library(data.table) library(bench) set.seed(123) n <- 10000 df <- data.frame( a = sample(1:5, n, replace = TRUE), b = sample(1:5, n, replace = TRUE), c = sample(1:5, n, replace = TRUE), d = sample(1:5, n, replace = TRUE), grp = sample(1:3, n, replac...
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Facebook Architecture [closed]

...g/post/358 You can use HipHop yourself: https://github.com/facebook/hiphop-php/wiki But if you ask me it's a very ambitious and probably time wasting task. Hiphop only supports so much, it can't simply convert everything to C++. So what does this tell us? Well, it tells us that Facebook is NOT full...
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download file using an ajax request

...ownload. Instead, you could use a success function to navigate to download.php. This will open the download prompt but won't change the current page. $.ajax({ url: 'download.php', type: 'POST', success: function() { window.location = 'download.php'; } }); Even though this ...
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How do you reindex an array in PHP?

... This will do what you want: <?php $array = array(2 => 'a', 1 => 'b', 0 => 'c'); array_unshift($array, false); // Add to the start of the array $array = array_values($array); // Re-number // Remove the first index so we start at 1 $array = arra...
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PHP shell_exec() vs exec()

...ide all output as an array specifed as the second parameter. See http://php.net/manual/en/function.shell-exec.php http://php.net/manual/en/function.exec.php share | improve this answer ...
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Write a number with two decimal places SQL server

...ters to display, and the number of decimal places to display Select Str(12345.6789, 12, 3) displays: ' 12345.679' ( 3 spaces, 5 digits 12345, a decimal point, and three decimal digits (679). - it rounds if it has to truncate, (unless the integer part is too large for the total size, in whic...
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Want to exclude file from “git diff”

I am trying to exclude a file ( db/irrelevant.php ) from a Git diff. I have tried putting a file in the db subdirectory called .gitattributes with the line irrelevant.php -diff and I have also tried creating a file called .git/info/attributes containing db/irrelevant.php . ...
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Remove a string from the beginning of a string

... want, where you can limit your replace to part of your string: http://nl3.php.net/manual/en/function.substr-replace.php (This will enable you to only look at the beginning of the string.) You could use the count parameter of str_replace ( http://nl3.php.net/manual/en/function.str-replace.php ), th...
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Running a Python script from PHP

I'm trying to run a Python script from PHP using the following command: 9 Answers 9 ...