#!/usr/bin/env python3

import numpy as np

# https://numpy.org/doc/stable/reference/random/generated/numpy.random.randn.html#numpy.random.randn
x = np.random.randn( 100 ) * 5 + 10 

print('x:\n',x)

print('Suma elementos x: ',x.sum()) 

print('Media x:',x.mean()) 

print('Varianza estándar x:',x.std()) 

print('Varianza x:',x.var())  

y = np.random.randn( 100 ) * 3 - 7
xy = np.vstack( [ x, y ] )
print('----------')
print('xy shape:',xy.shape) #  (2, 100)
print('xy:\n',xy)


print('----------')
print('Covariance matrix:\n\n',np.cov(xy))
print('----------')


xy = np.random.multivariate_normal( [7,5], [[36,-9],[-9,49]], 10) 

xy.sum(axis=1)
xy.mean(axis=0)
xy.std(axis=0)
xy.var(axis=0)

x = np.random.rand( 10000 ) * 100
hist,bin_edges = np.histogram( x, bins=20, density=False )
print( hist )


hist,bin_edges = np.histogram( x, bins=20, density=True )
print( hist, hist.sum(), bin_edges[1]-bin_edges[0] )
print( bin_edges ) # The same in both cases