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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:
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Regex to check whether a string contains only numbers [duplicate]
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This one will allow also for signed and float numbers or empty string:
var reg = /^-?\d*\.?\d*$/
If you don't want allow to empty string use this one:
var reg = /^-?\d+\.?\d*$/
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How to get the nvidia driver version from the command line?
... example:
$ cat /proc/driver/nvidia/version
NVRM version: NVIDIA UNIX x86_64 Kernel Module 304.54 Sat Sep 29 00:05:49 PDT 2012
GCC version: gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5)
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Changing UIImage color
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Swift 4.2 Solution
extension UIImage {
func withColor(_ color: UIColor) -> UIImage {
UIGraphicsBeginImageContextWithOptions(size, false, scale)
guard let ctx = UIGraphicsGetCurrentContext(), let cgImage = cgImage else { return self }
color.setFill()
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How do I scale a stubborn SVG embedded with the tag?
...nd this information here:
https://blueprints.launchpad.net/inkscape/+spec/allow-browser-resizing
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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...
Is there a “do … until” in Python? [duplicate]
...is is a similar construct, taken from the link above.
while True:
do_something()
if condition():
break
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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();
}
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