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Difference between map, applymap and apply methods in Pandas
Can you tell me when to use these vectorization methods with basic examples?
10 Answers
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How to use glOrtho() in OpenGL?
I can't understand the usage of glOrtho . Can someone explain what it is used for?
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When should I use Lazy?
I found this article about Lazy : Laziness in C# 4.0 – Lazy
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Automatically expanding an R factor into a collection of 1/0 indicator variables for every factor le
I have an R data frame containing a factor that I want to "expand" so that for each factor level, there is an associated column in a new data frame, which contains a 1/0 indicator. E.g., suppose I have:
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For i = 0, why is (i += i++) equal to 0?
Take the following code (usable as a Console Application):
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Does ruby have real multithreading?
I know about the "cooperative" threading of ruby using green threads . How can I create real "OS-level" threads in my application in order to make use of multiple cpu cores for processing?
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Is this a “good enough” random algorithm; why isn't it used if it's faster?
I made a class called QuickRandom , and its job is to produce random numbers quickly. It's really simple: just take the old value, multiply by a double , and take the decimal part.
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How to scale down a range of numbers with a known min and max value
So I am trying to figure out how to take a range of numbers and scale the values down to fit a range. The reason for wanting to do this is that I am trying to draw ellipses in a java swing jpanel. I want the height and width of each ellipse to be in a range of say 1-30. I have methods that find t...
Is MATLAB OOP slow or am I doing something wrong?
I'm experimenting with MATLAB OOP , as a start I mimicked my C++'s Logger classes and I'm putting all my string helper functions in a String class, thinking it would be great to be able to do things like a + b , a == b , a.find( b ) instead
of strcat( a b ) , strcmp( a, b ) , retrieve first...
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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