Python 如何将此累积操作矢量化?
设Python 如何将此累积操作矢量化?,python,numpy,Python,Numpy,设W为维度的矩阵(x,nP)[见问题末尾] 现在,我正在执行以下代码: uUpperDraw = np.zeros(W.shape) for p in np.arange(0, nP): uUpperDraw[s, p] = (W[s+1,:(p+1)]).sum() 我想将其矢量化以提高效率。给定一个pGrid=[0,1,…],我如何重现以下内容 uUpperDraw = np.array([sum(W[x, 0]), sum(W[x,0] + W[x, 1]), sum(W[x,0
W
为维度的矩阵(x,nP)
[见问题末尾]
现在,我正在执行以下代码:
uUpperDraw = np.zeros(W.shape)
for p in np.arange(0, nP):
uUpperDraw[s, p] = (W[s+1,:(p+1)]).sum()
我想将其矢量化以提高效率。给定一个pGrid=[0,1,…]
,我如何重现以下内容
uUpperDraw = np.array([sum(W[x, 0]), sum(W[x,0] + W[x, 1]), sum(W[x,0] + W[x, 1] + W[x, 2]) ...
这里有一些可重复的例子
>>> s, nP
(3, 10)
>>> W
array([[ 0. , 0. , 0. , 0. , 0. ,
0. , 0. , 0. , 0. , 0. ],
[ 0. , 0. , 0. , 0. , 0. ,
0. , 0. , 0. , 0. , 0. ],
[ 0. , 0. , 0. , 0. , 0. ,
0. , 0. , 0. , 0. , 0. ],
[ 0. , 0. , 0. , 0. , 0. ,
0. , 0. , 0. , 0. , 0. ],
[ 2. , 1.63636364, 1.38461538, 1.2 , 1.05882353,
0.94736842, 0.85714286, 0.7826087 , 0.72 , 0.66666667]])
>>> uUpperDraw
array([[ 0. , 0. , 0. , 0. ,
0. , 0. , 0. , 0. ,
0. , 0. ],
[ 0. , 0. , 0. , 0. ,
0. , 0. , 0. , 0. ,
0. , 0. ],
[ 0. , 0. , 0. , 0. ,
0. , 0. , 0. , 0. ,
0. , 0. ],
[ 2. , 3.63636364, 5.02097902, 6.22097902,
7.27980255, 8.22717097, 9.08431383, 9.86692252,
10.58692252, 11.25358919],
[ 0. , 0. , 0. , 0. ,
0. , 0. , 0. , 0. ,
0. , 0. ]])
这看起来像是累积的总和。当你想把每一行的累计总和分开计算时,这里的方法就行了
uUpperDraw = np.cumsum(W,axis=1)
是的,就是这个!我错过了!但首先我认为OP正在寻找python解决方案!经验法则:不要在numpy对象上使用for循环。Travis pas含量。