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How can I convert a string to boolean in JavaScript?
Can I convert a string representing a boolean value (e.g., 'true', 'false') into a intrinsic type in JavaScript?
83 Answers...
How to select where ID in Array Rails ActiveRecord without exception
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If it is just avoiding the exception you are worried about, the "find_all_by.." family of functions works without throwing exceptions.
Comment.find_all_by_id([2, 3, 5])
will work even if some of the ids don't exist. This works in the
user.c...
How to get instance variables in Python?
Is there a built-in method in Python to get an array of all a class' instance variables? For example, if I have this code:
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What should I name a table that maps two tables together? [closed]
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There are only two hard things in
Computer Science: cache invalidation
and naming things-- Phil Karlton
Coming up with a good name for a table that represents a many-to-many relationship makes the relationship easier to read and understand. Someti...
Get file name from URI string in C#
I have this method for grabbing the file name from a string URI. What can I do to make it more robust?
8 Answers
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Big O, how do you calculate/approximate it?
Most people with a degree in CS will certainly know what Big O stands for .
It helps us to measure how well an algorithm scales.
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Java 8 Stream and operation on arrays
I have just discovered the new Java 8 stream capabilities. Coming from Python, I was wondering if there was now a neat way to do operations on arrays like summing, multiplying two arrays in a "one line pythonic" way ?
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Drop rows with all zeros in pandas data frame
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It turns out this can be nicely expressed in a vectorized fashion:
> df = pd.DataFrame({'a':[0,0,1,1], 'b':[0,1,0,1]})
> df = df[(df.T != 0).any()]
> df
a b
1 0 1
2 1 0
3 1 1
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How do JavaScript closures work?
...h a knowledge of the concepts they consist of (for example functions, variables and the like), but does not understand closures themselves?
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Thread context switch Vs. process context switch
...main distinction between a thread switch and a process switch is that during a thread switch, the virtual memory space remains the same, while it does not during a process switch.
Both types involve handing control over to the operating system kernel to perform the context switch. The process of swi...