Automating to save generated data

[scidam]

I didn't test it, but something like the following should help you:

L = 1000
data = np.random.rand(4064, 1)

for j in range(data.shape[0] // L):
    mapper = np.memmap(f'map{j}.dat', dtype='float64', mode='w+', shape=(L,1))
    mapper = data[j*L:j*L+L]

if data.shape[0] % L != 0:
    mapper = np.memmap(f'map{j+1}.dat', dtype='float64', mode='w+', shape=(data.shape[0] % L,1))
    mapper = data[j*L + L:]