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When should I use Struct vs. OpenStruct?
In general, what are the advantages and disadvantages of using an OpenStruct as compared to a Struct? What type of general use-cases would fit each of these?
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Version number comparison in Python
I want to write a cmp -like function which compares two version numbers and returns -1 , 0 , or 1 based on their compared valuses.
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How to validate date with format “mm/dd/yyyy” in JavaScript?
...;
var year = parseInt(parts[2], 10);
// Check the ranges of month and year
if(year < 1000 || year > 3000 || month == 0 || month > 12)
return false;
var monthLength = [ 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 ];
// Adjust for leap years
if(year % 400...
What is a loop invariant?
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@Tomas Petricek - when the loop terminates, i = 10 and j = -1; so the weaker invariant example you gave may not be correct (?)
– Raja
Apr 7 '12 at 22:47
7
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Is there a builtin identity function in python?
...ng some more research, there is none, a feature was asked in issue 1673203 And from Raymond Hettinger said there won't be:
Better to let people write their own trivial pass-throughs
and think about the signature and time costs.
So a better way to do it is actually (a lambda avoids naming the...
What does .SD stand for in data.table in R
...ks useful but I do not really know what I am doing with it. What does it stand for? Why is there a preceding period (full stop). What is happening when I use it?
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Restart node upon changing a file
For someone who is coming from PHP background the process of killing node and starting it again after every code change, seems very tedious. Is there any flag when starting a script with node to automatically restart node when code change is saved?
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How to access the last value in a vector?
... vector that is nested in a dataframe one or two levels. Is there a quick and dirty way to access the last value, without using the length() function? Something ala PERL's $# special var?
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How to Correctly Use Lists in R?
...st?) contemporary programming languages in widespread use have at least a handful of ADTs [abstract data types] in common, in particular,
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how to use sed, awk, or gawk to print only what is matched?
I see lots of examples and man pages on how to do things like search-and-replace using sed, awk, or gawk.
11 Answers
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