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not None test in Python [duplicate]
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1033
if val is not None:
# ...
is the Pythonic idiom for testing that a variable is not set to...
How to escape braces (curly brackets) in a format string in .NET
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For you to output foo {1, 2, 3} you have to do something like:
string t = "1, 2, 3";
string v = String.Format(" foo {{{0}}}", t);
To output a { you use {{ and to output a } you use }}.
or Now, you can also use c# string interpolation like this (featu...
How to split a string in shell and get the last field
Suppose I have the string 1:2:3:4:5 and I want to get its last field ( 5 in this case). How do I do that using Bash? I tried cut , but I don't know how to specify the last field with -f .
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Fast permutation -> number -> permutation mapping algorithms
I have n elements. For the sake of an example, let's say, 7 elements, 1234567. I know there are 7! = 5040 permutations possible of these 7 elements.
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Preferred way to create a Scala list
...end is O(1).
– Daniel C. Sobral
Aug 31 '15 at 19:33
@pgoggijr That is not true. First, there's no "change" anywhere, b...
Getting a map() to return a list in Python 3.x
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Do this:
list(map(chr,[66,53,0,94]))
In Python 3+, many processes that iterate over iterables return iterators themselves. In most cases, this ends up saving memory, and should make things go faster.
If all you're going to do is iterate over thi...
How to extract a floating number from a string [duplicate]
I have a number of strings similar to Current Level: 13.4 db. and I would like to extract just the floating point number. I say floating and not decimal as it's sometimes whole. Can RegEx do this or is there a better way?
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How to get one value at a time from a generator function in Python?
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answered Mar 10 '10 at 19:13
Ignacio Vazquez-AbramsIgnacio Vazquez-Abrams
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Regex to remove all (non numeric OR period)
I need for text like "joe ($3,004.50)" to be filtered down to 3004.50 but am terrible at regex and can't find a suitable solution. So only numbers and periods should stay - everything else filtered. I use C# and VS.net 2008 framework 3.5
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What is the significance of initializing direction arrays below with given values when developing ch
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