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Fastest way to flatten / un-flatten nested JSON objects
I threw some code together to flatten and un-flatten complex/nested JSON objects. It works, but it's a bit slow (triggers the 'long script' warning).
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Computational complexity of Fibonacci Sequence
I understand Big-O notation, but I don't know how to calculate it for many functions. In particular, I've been trying to figure out the computational complexity of the naive version of the Fibonacci sequence:
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Cycles in family tree software
I am the developer of some family tree software (written in C++ and Qt). I had no problems until one of my customers mailed me a bug report. The problem is that the customer has two children with their own daughter, and, as a result, he can't use my software because of errors.
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Memoization in Haskell?
...f :: Int -> Int
faster_f n = f_list !! n
That performs passably well, and replaces what was going to take O(n^3) time with something that memoizes the intermediate results.
But it still takes linear time just to index to find the memoized answer for mf. This means that results like:
*Main Dat...
Qt 5.1.1: Application failed to start because platform plugin “windows” is missing
...er people by directly providing the solution. This should not be forgotten and so far my answer helped a lot of people. Therefore my question is definitely not a duplicate. By the way: The accepted answer within the provided link on top does not solve the problem !
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Checking if a string can be converted to float in Python
I've got some Python code that runs through a list of strings and converts them to integers or floating point numbers if possible. Doing this for integers is pretty easy
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NumPy: function for simultaneous max() and min()
numpy.amax() will find the max value in an array, and numpy.amin() does the same for the min value. If I want to find both max and min, I have to call both functions, which requires passing over the (very big) array twice, which seems slow.
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What do hjust and vjust do when making a plot using ggplot?
...lot using ggplot, I spend a little while trying different values for hjust and vjust in a line like
2 Answers
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C fopen vs open
..., there is no particularly good reason to use fdopen if fopen is an option and open is the other possible choice. You shouldn't have used open to open the file in the first place if you want a FILE *. So including fdopen in that list is incorrect and confusing because it isn't very much like the oth...
How to add an extra column to a NumPy array
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I think a more straightforward solution and faster to boot is to do the following:
import numpy as np
N = 10
a = np.random.rand(N,N)
b = np.zeros((N,N+1))
b[:,:-1] = a
And timings:
In [23]: N = 10
In [24]: a = np.random.rand(N,N)
In [25]: %timeit b = np.hstac...