Setting a relative frequency in a matplotlib histogram

Question

I have data as a list of floats and I want to plot it as a histogram. Hist() function does the job perfectly for plotting the absolute histogram. However, I cannot figure ou

Answer 1

Or you can use set_major_formatter to adjust the scale of the y-axis, as follows:

from matplotlib import ticker as tick

def adjust_y_axis(x, pos):
    return x / (len(mydata) * 1.0)

ax.yaxis.set_major_formatter(tick.FuncFormatter(adjust_y_axis))

just call adjust_y_axis as above before plt.show().

Answer 2

Because normed option of hist returns the density of points, e.g dN/dx

What you need is something like that:

 # assuming that mydata is an numpy array
 ax.hist(mydata, weights=np.zeros_like(mydata) + 1. / mydata.size)
 # this will give you fractions