type(numpy.array) output: numpy.ndarray

nparray.dtype output:float64

can only contains one type of data

np.array.size #no of elements

np.array[0] #index

np.array[np.array > x] # find value by compare element

.sum()

np.mean()

np.median()

.std()

.min()

.max()

np.corrcoef (e1,e2)

np.sort()

normal - stad normal distribution

rand - normal dist. between 0 and 1

rand - uniform distribution

binomial distribution

beta distribution

chi-square distribution

gamma distribution

np.colum_stack()

np.row_stack()