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What is the difference between .*? and .* regular expressions?

... It is the difference between greedy and non-greedy quantifiers. Consider the input 101000000000100. Using 1.*1, * is greedy - it will match all the way to the end, and then backtrack until it can match 1, leaving you with 1010000000001. .*? is non-greedy. * w...
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What's the difference between a web site and a web application? [closed]

I'm stumped trying to come up to a difference between a website and a web application for myself. As I see it, a web site points to a specific page and a web application is more of some sort of 'portal' to content and information. ...
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How do I clone a Django model instance object and save it to the database?

... Just change the primary key of your object and run save(). obj = Foo.objects.get(pk=<some_existing_pk>) obj.pk = None obj.save() If you want auto-generated key, set the new key to None. More on UPDATE/INSERT here. Official docs on copying model instances: h...
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Check folder size in Bash

I'm trying to write a script that will calculate a directory size and if the size is less than 10GB, and greater then 2GB do some action. Where do I need to mention my folder name? ...
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Apply a function to every row of a matrix or a data frame

Suppose I have a n by 2 matrix and a function that takes a 2-vector as one of its arguments. I would like to apply the function to each row of the matrix and get a n-vector. How to do this in R? ...
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Fetch frame count with ffmpeg

...deo file using ffmpeg? The render output of ffmpeg shows the current frame and I need the frame count to calculate the progress in percent. ...
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How do I choose grid and block dimensions for CUDA kernels?

This is a question about how to determine the CUDA grid, block and thread sizes. This is an additional question to the one posted here . ...
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Is there a Python function to determine which quarter of the year a date is in?

...ed to count from 1 instead;-). Originally two answers, multiply upvoted and even originally accepted (both currently deleted), were buggy -- not doing the -1 before the division, and dividing by 4 instead of 3. Since .month goes 1 to 12, it's easy to check for yourself what formula is right: fo...
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Why don't C++ compilers define operator== and operator!=?

...ison or a deep (internal) comparison. It's safer to just not implement it and let the programmer do that themselves. Then they can make all the assumptions they like. share | improve this answer ...
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What is the intent of the methods getItem and getItemId in the Android class BaseAdapter?

I'm curious about the purpose of the methods getItem and getItemId in the class Adapter in the Android SDK. 6 Answers ...