python - How to append numpy.array to other numpy.array? -

i want create 2d numpy.array knowing @ begining shape, i.e shape=2. now, want create in for loop ith 1 dimensional numpy.arrays, , add them main matrix of shape=2, i'll this:

matrix= [numpy.array 1] [numpy.array 2] ... [numpy.array n] 

how can achieve that? try use:

matrix = np.empty(shape=2) in np.arange(100):     array = np.zeros(random_value)     matrix = np.append(matrix, array) 

but result of print(np.shape(matrix)), after loop, like:

(some_number, ) 

how can append each new array in next row of matrix? thank in advance.

i suggest working list

matrix = []  in range(10):     = np.ones(2)     matrix.append(a)  matrix = np.array(matrix) 

list not have downside of being copied in memory everytime use append. avoid problem described ali_m. @ end of operation convert list object numpy array.