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What exactly does the .join() method do?
I'm pretty new to Python and am completely confused by .join() which I have read is the preferred method for concatenating strings.
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Is Java's assertEquals method reliable?
I know that == has some issues when comparing two Strings . It seems that String.equals() is a better approach. Well, I'm doing JUnit testing and my inclination is to use assertEquals(str1, str2) . Is this a reliable way to assert two Strings contain the same content? I would use assertTr...
warning about too many open figures
In a script where I create many figures with fix, ax = plt.subplots(...) , I get the warning RuntimeWarning: More than 20 figures have been opened. Figures created through the pyplot interface (matplotlib.pyplot.figure) are retained until explicitly closed and may consume too much memory.
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Count number of rows within each group
I have a dataframe and I would like to count the number of rows within each group. I reguarly use the aggregate function to sum data as follows:
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Is it possible to print a variable's type in standard C++?
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What do ellipsis […] mean in a list?
I was playing around in python. I used the following code in IDLE:
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Is there a way to do repetitive tasks at intervals?
Is there a way to do repetitive background tasks in Go? I'm thinking of something like Timer.schedule(task, delay, period) in Java. I know I can do this with a goroutine and Time.sleep() , but I'd like something that easily stopped.
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How to sleep for five seconds in a batch file/cmd [duplicate]
Windows's Snipping tool can capture the screen, but sometimes I want to capture the screen after five seconds, such as taking an image being displayed by the webcam. (Run the script and smile at the camera, for example.)
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Is there a simple way to delete a list element by value?
I want to remove a value from a list if it exists in the list (which it may not).
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List comprehension: Returning two (or more) items for each item
Is it possible to return 2 (or more) items for each item in a list comprehension?
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