I have the following Python 2.7 code:
listOfLists = []
for l1_index, l1 in enumerate(L1):list = []for l2 in L2:for l3_index,l3 in enumerate(L3):if (L4[l2-1] == l3):value = L5[l2-1] * l1[l3_index]list.append(value)breaklistOfLists.append(list)
with the L1,L2,L3,L4,L5 lists being:
L1 = [[0.60, 0.95, 0.38, 1.02, 0.29, 0.43], [0.40, 0.09, 0.87, 0.85, 0.70, 0.46], [0.67, 0.91, 0.66, 0.79, 0.86, 0.06], [0.59, 1.81, 0.05, 1.88, 0.20, 0.48], [0.64, 0.34, 0.37, 1.39, 0.56, 0.27], [0.56, 0.34, 0.68, 2.79, 0.18, 0.42], [0.42, 1.67, 0.04, 0.44, 0.25, 0.94], [0.32, 1.92, 0.95, 2.85, 0.95, 0.96], [0.50, 0.68, 0.84, 1.79, 0.35, 0.09], [0.34, 0.66, 0.85, 0.35, 0.38, 0.59], [0.50, 0.79, 0.45, 2.93, 0.50, 0.92], [0.11, 0.11, 0.93, 1.11, 0.81, 0.49]] # a list of 12 sublists
L2 = [3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]
L3 = [480, 120, 35, 0, 520, 300]
L4 = [120, 120, 120, 0, 300, 35, 35, 520, 300, 480, 120, 480, 0, 35, 0, 0, 300]
L5 = [5.4, 2.83, 1.16, 6.9, 0.76, 2.15, 5.61, 3.12, 1.57, 0.08, 5.36, 0.2, 1.2, 1.4, 2.9, 2.1, 3.5]
These are only examples; in reality the lists contain hundreds of thousands of numbers. The interpreter takes tens of seconds to calculate the three nested for
loops.
Is it possible to somehow speed up this code, e.g. using itertools
or any other module/function?
EDIT: I can not use non-standard python 2.7 modules (numpy, scipy...)