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Java: random long number in 0
Random class has a method to generate random int in a given range. For example:
16 Answers
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Favicon dimensions? [duplicate]
I have a favicon with the dimensions of height=26px / width=20px named favicon.png
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Is there a way to get the XPath in Google Chrome?
I have a webpage I want to use with YQL. But I need the XPath of a specific item. I can see it in the debug tools area for Google Chrome but I don't see a way to copy that XPath.
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How to test if list element exists?
I would like to test if an element of a list exists, here is an example
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What is recursion and when should I use it?
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Is double square brackets [[ ]] preferable over single square brackets [ ] in Bash?
...ewer surprises and is generally safer to use. But it is not portable - POSIX doesn't specify what it does and only some shells support it (beside bash, I heard ksh supports it too). For example, you can do
[[ -e $b ]]
to test whether a file exists. But with [, you have to quote $b, because it sp...
What's the difference between `=` and `
...as the operator = is only allowed at the top level (e.g., in the complete expression typed at the command prompt) or as one of the subexpressions in a braced list of expressions.
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Pairwise crossproduct in Python [duplicate]
...,5,6]
>>> itertools.product(a,b)
<itertools.product object at 0x10049b870>
>>> list(itertools.product(a,b))
[(1, 4), (1, 5), (1, 6), (2, 4), (2, 5), (2, 6), (3, 4), (3, 5), (3, 6)]
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Error in if/while (condition) {: missing Value where TRUE/FALSE needed
...where TRUE/FALSE needed
To test whether an object is missing use is.na(x) rather than x == NA.
See also the related errors:
Error in if/while (condition) { : argument is of length zero
Error in if/while (condition) : argument is not interpretable as logical
if (NULL) {}
## Error in if (NUL...
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