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Can dplyr package be used for conditional mutating?
...and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using na_if at the end to replace 0 with NA.
df %>%
mutate(g = 2 * (a == 2 ...
Facebook Open Graph not clearing cache
...fresh even if you delete the thumnail/image from your server. But Facebook allows you to refresh by using fbrefresh
I hope this helps.
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Importing CommonCrypto in a Swift framework
...mething a little simpler and more robust is to create an Aggregate target called "CommonCryptoModuleMap" with a Run Script phase to generate the module map automatically and with the correct Xcode/SDK path:
The Run Script phase should contain this bash:
# This if-statement means we'll only run ...
Convert Elixir string to integer or float
...er directly. If you want to do that, see @Szymon Jeż answer with String.to_integer/1
– user4275029
Sep 26 '16 at 12:27
6
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What are file descriptors, explained in simple terms?
...you open a network socket, it is also represented by an integer and it is called Socket Descriptor.
I hope you understand.
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Collection was modified; enumeration operation may not execute
...
Is that a complete example? I have a class (_dictionary obj below) that contains a generic Dictionary<string,int> named MarkerFrequencies, but doing this didn't instantly solve the crash: lock (_dictionary.MarkerFrequencies) { foreach (KeyValuePair<string, int...
Can you call Directory.GetFiles() with multiple filters?
...er,
var files = Directory.EnumerateFiles("C:\\path", "*.*", SearchOption.AllDirectories)
.Where(s => s.EndsWith(".mp3") || s.EndsWith(".jpg"));
For earlier versions of .NET,
var files = Directory.GetFiles("C:\\path", "*.*", SearchOption.AllDirectories)
.Where(s => ...
Detecting a redirect in ajax request?
...ttpRequest object directly.
You can use something like this:
var xhr;
var _orgAjax = jQuery.ajaxSettings.xhr;
jQuery.ajaxSettings.xhr = function () {
xhr = _orgAjax();
return xhr;
};
jQuery.ajax('http://test.com', {
success: function(responseText) {
console.log('responseURL:', xhr.respon...
Why use static_cast(x) instead of (int)x?
...e main reason is that classic C casts make no distinction between what we call static_cast<>(), reinterpret_cast<>(), const_cast<>(), and dynamic_cast<>(). These four things are completely different.
A static_cast<>() is usually safe. There is a valid conversion in the...
Best approach for designing F# libraries for use from both F# and C#
... function that you wrote, so I'll add some higher-level comments. First of all, you should read the F# Component Design Guidelines (referenced already by gradbot). This is a document that explains how to design F# and .NET libraries using F# and it should answer many of your questions.
When using F...