python 将数组写入文件

简介

常用功能

code

import numpy as np
import time
test_data = np.random.rand(6000000,12)
T1 = time.time()
np.savetxt('test',test_data, fmt='%.4f', delimiter=' ' )
T2 = time.time() 
print "Time:",T2-T1,"Sec"
file3=open('test2','w')
for i in range(6000000):
    for j in range(12):
        file3.write('%6.4f\t' % (test_data[i][j]))
    file3.write('\n')
T3 = time.time() 
print "Time:",T3-T2,"Sec"