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pythonmatplotlibhistogram

Bin size in Matplotlib (Histogram)

I'm using matplotlib to make a histogram.

Is there any way to manually set the size of the bins as opposed to the number of bins?

Solution

  • Actually, it's quite easy: instead of the number of bins you can give a list with the bin boundaries. They can be unequally distributed, too:

    plt.hist(data, bins=[0, 10, 20, 30, 40, 50, 100])

    If you just want them equally distributed, you can simply use range:

    plt.hist(data, bins=range(min(data), max(data) + binwidth, binwidth))

    Added to original answer

    The above line works for data filled with integers only. As macrocosme points out, for floats you can use:

    import numpy as np
plt.hist(data, bins=np.arange(min(data), max(data) + binwidth, binwidth))