小编Son*_*box的帖子

使用Python NumPy计算矩阵列的总和:

import numpy
from StringIO import StringIO

fileName = 'test2.csv'
myFile = open(fileName,'r')
print "Reading data from '%s' ..." % fileName
data = myFile.read() 
myFile.close()

data = numpy.genfromtxt(StringIO(data), delimiter=',', usecols=(0,1,2))
print "Calculating ..."

print data[:,2]
sumA1 = data[:,2].sum
print "shape =", data.shape
print "sumA1 =", str(sumA1)
print "ok"

然后内容test2.csv:

12,13,14,17
1,2,3,4
12,13,14,17
1,2,3,4
12,13,14,17
1,2,3,4
12,13,14,17
1,2,3,4
12,13,14,17

我得到了这个输出

Reading data from 'test2.csv' ...
Calculating ...
[ 14.   3.  14.   3.  14.   3.  14.   3.  14.]
shape …