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How do I get the difference between two Dates in JavaScript?
...uite figure out, however, how to get the difference between the two times, and then how to create a new end Date using that difference.
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How can I import Swift code to Objective-C?
I have written a library in Swift and I wasn't able to import it to my current project, written in Objective-C.
15 Answers
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What is a good Hash Function?
What is a good Hash function? I saw a lot of hash function and applications in my data structures courses in college, but I mostly got that it's pretty hard to make a good hash function. As a rule of thumb to avoid collisions my professor said that:
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How do I choose between Semaphore and SemaphoreSlim?
... documentation states that the SemaphoreSlim is a lightweight alternative and doesn't use Windows Kernel semaphores. This resource states that the SemaphoreSlim is much faster. In what situations does the SemaphoreSlim make more sense over the Semaphore and vice versa?
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Convert string to number and add one
I want to turn the value I get from the id into a number and add one to it then pass the new value into the dosomething() function to use. When I tried this and the value is one I get back 11 not 2.
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MySQL - Get row number on select
Can I run a select statement and get the row number if the items are sorted?
5 Answers
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How do you change the size of figures drawn with matplotlib?
...figsize=(8, 6), ...) to change it's size etc. If you're using pyplot/pylab and show() to create a popup window, you need to call figure(num=1,...) before you plot anything - pyplot/pylab creates a figure as soon as you draw something, and the size of the popup appears to be fixed at this point.
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How do I generate random number for each row in a TSQL Select?
I need a different random number for each row in my table. The following seemingly obvious code uses the same random value for each row.
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Can Java 8 code be compiled to run on Java 7 JVM?
... code requires you to target a 1.8 VM. I just tried the new Java 8 release and tried compiling with -target 1.7 -source 1.8, and the compiler refuses:
$ javac Test -source 1.8 -target 1.7
javac: source release 1.8 requires target release 1.8
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Dynamically select data frame columns using $ and a character value
I have a vector of different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic s...