import numpy as np
H = [12,12,5,32,6,0.5]
P=H.max()
S=[22, 33, 45.6, 21.6, 51.8]
SP = P*np.array(S)

import numpy as np
H = [12,12,5,32,6,0.5]
S=[22, 33, 45.6, 21.6, 51.8]
SP = H.max()*np.array(S)

In [74]:

import numpy as np
H = np.random.random(100000)
%timeit P=H.max()
S=np.random.random(100000)
%timeit SP = P*np.array(S)
%timeit SP = H.max()*np.array(S)
10000 loops, best of 3: 51.2 µs per loop
10000 loops, best of 3: 165 µs per loop
1000 loops, best of 3: 217 µs per loop