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Determine the number of NA values in a column
...nt the number of NA values in a data frame column. Say my data frame is called df , and the name of the column I am considering is col . The way I have come up with is following:
...
How do I get the current date and time in PHP?
...e time would go by your server time. An easy workaround for this is to manually set the timezone by using date_default_timezone_set before the date() or time() functions are called to.
I'm in Melbourne, Australia so I have something like this:
date_default_timezone_set('Australia/Melbourne');
Or...
C# if/then directives for debug vs release
...em only executed if a certain symbol is defined. The compiler would remove all calls to those methods if the symbol is not defined:
[Conditional("DEBUG")]
void PrintLog() {
Console.WriteLine("Debug info");
}
void Test() {
PrintLog();
}
...
How can I do division with variables in a Linux shell?
... It has to be noted somewhere on this page that most (if not all) GNU/Linux shells only perform integer operations.
– Skippy le Grand Gourou
Sep 19 '14 at 12:47
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Accessing the web page's HTTP Headers in JavaScript
... exactly equal to the current.
Use the following JavaScript code to get all the HTTP headers by performing a get request:
var req = new XMLHttpRequest();
req.open('GET', document.location, false);
req.send(null);
var headers = req.getAllResponseHeaders().toLowerCase();
alert(headers);
...
What use is find_package() if you need to specify CMAKE_MODULE_PATH anyway?
...e. Now the software has a few dependencies. I compiled them myself and installed them on my system.
4 Answers
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How to set the UITableView Section title programmatically (iPhone/iPad)?
... answered May 8 '12 at 20:27
AlladinianAlladinian
31.3k44 gold badges7575 silver badges8181 bronze badges
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UnmodifiableMap (Java Collections) vs ImmutableMap (Google) [duplicate]
...// Will return "F".
In contrast to that, the ImmutableMap of Guava is really immutable: It is a true copy of a given map, and nobody may modify this ImmutableMap in any way.
Update:
As pointed out in a comment, an immutable map can also be created with the standard API using
Map<String, S...
Fragment over another fragment issue
...lns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:clickable="true" />
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How to replace a character by a newline in Vim
...s a newline (more precisely, it’s treated as the input CR). Here’s a small, non-interactive example to illustrate this, using the Vim command line feature (in other words, you can copy and paste the following into a terminal to run it). xxd shows a hexdump of the resulting file.
echo bar > te...