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How to check if a variable is not null?
...n case for those wondering... This does not check for an empty string ("") and undefined. See my fiddle as reference: jsfiddle.net/b0tm7yaf
– Barrosy
Jan 18 '19 at 15:25
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For each row in an R dataframe
I have a dataframe, and for each row in that dataframe I have to do some complicated lookups and append some data to a file.
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How to perform runtime type checking in Dart?
...
is and is! can be found in the Operators section of the Dart language tour.
– Curly
Jun 25 '19 at 16:02
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Rails I18n validation deprecation warning
I just updated to rails 4.0.2 and I'm getting this warning:
5 Answers
5
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Sorting arraylist in alphabetical order (case insensitive)
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can u tell me what is string s1 and s2?and how can see the result if the compare function returning integer value.
– andro-girl
Apr 28 '11 at 8:01
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How to force a line break in a long word in a DIV?
...ern browser. IE, being a dead browser, will forever rely on the deprecated and non-standard word-wrap instead.
Existing uses of word-wrap today still work as it is an alias for overflow-wrap per the specification.
share
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Convert audio files to mp3 using ffmpeg
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You could use this command:
ffmpeg -i input.wav -vn -ar 44100 -ac 2 -b:a 192k output.mp3
Explanation of the used arguments in this example:
-i - input file
-vn - Disable video, to make sure no video (including album cover image) is included if...
How to avoid scientific notation for large numbers in JavaScript?
...umber.toFixed, but it uses scientific notation if the number is >= 1e21 and has a maximum precision of 20. Other than that, you can roll your own, but it will be messy.
function toFixed(x) {
if (Math.abs(x) < 1.0) {
var e = parseInt(x.toString().split('e-')[1]);
if (e) {
x *...
Formatting Decimal places in R
...number of decimal places are displayed. This is often done for consistency and standardisation purposes rather than being concerned with significant figures.
Solution:
The following code shows exactly two decimal places for the number x.
format(round(x, 2), nsmall = 2)
For example:
format(roun...
Is there a Python equivalent of the C# null-coalescing operator?
...ator does not return only True or False. Instead, it returns the first operand if the first operand evaluates to true, and it returns the second operand if the first operand evaluates to false.
In this case, the expression x or y returns x if it is True or evaluates to true when converted to boolea...