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Random number generator only generating one random number
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Every time you do new Random() it is initialized using the clock. This means that in a tight loop you get the same value lots of times. You should keep a single Random instance and keep using Next on the same instance.
//Function to get a random n...
Associative arrays in Shell scripts
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To add to Irfan's answer, here is a shorter and faster version of get() since it requires no iteration over the map contents:
get() {
mapName=$1; key=$2
map=${!mapName}
value="$(echo $map |sed -e "s/.*--${key}=\([^ ]*\).*/\1/" -e 's/:SP:/ /g' )"
}
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How can I check for NaN values?
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math.isnan(x)
Return True if x is a NaN (not a number), and False otherwise.
>>> import math
>>> x = float('nan')
>>> math.isnan(x)
True
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Add table row in jQuery
... isn't bulletproof as you could theoretically have multiple tbody elements and the row would get added to each of them.
Weighing everything up, I'm not sure there is a single one-line solution that accounts for every single possible scenario. You will need to make sure the jQuery code tallies with ...
“Inner exception” (with traceback) in Python?
My background is in C# and I've just recently started programming in Python. When an exception is thrown I typically want to wrap it in another exception that adds more information, while still showing the full stack trace. It's quite easy in C#, but how do I do it in Python?
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How to pause for specific amount of time? (Excel/VBA)
...se the Wait method:
Application.Wait Now + #0:00:01#
or (for Excel 2010 and later):
Application.Wait Now + #12:00:01 AM#
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Algorithm to generate a crossword
...Basically:
Sort all the words by length, descending.
Take the first word and place it on the board.
Take the next word.
Search through all the words that are already on the board and see if there are any possible intersections (any common letters) with this word.
If there is a possible location fo...
How do I add more members to my ENUM-type column in MySQL?
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Most ALTER TABLE commands will completely rewrite the whole table. Is mysql clever enough to not do that with enum ?
– John
Oct 9 '18 at 22:10
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Database design for a survey [closed]
...estions. For example: text fields for comments, multiple choice questions, and possibly questions that could contain more than one answer (i.e. check all that apply).
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ActiveRecord, has_many :through, and Polymorphic Associations
...owever, is there any way to accomplish this these days without source_type and two separate associations?
– Emeka
Feb 27 '16 at 15:27
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