Matlab 到 Python：为什么我们会收到错误

Question

它在 MATLAB / OCTAVE 中工作 - 我怎样才能在 Python 中正确修复它：

octave:40> whos YDFA_ale_ase
Variables in the current scope:

   Attr Name              Size                     Bytes  Class
   ==== ====              ====                     =====  ===== 
        YDFA_ale_ase     51x1                        408  double

Total is 51 elements using 408 bytes

octave:41> whos N1
Variables in the current scope:

   Attr Name        Size                     Bytes  Class
   ==== ====        ====                     =====  ===== 
        N1          1x1200                    9600  double

Total is 1200 elements using 9600 bytes

octave:45> YDFA_ale_ase * N1
ans =

 Columns 1 through 20:

   46.8270   46.8270   46.8270 
..........................

但是在 Python 中我得到以下错误：

np.dot(YDFA_ale_ase, 1.-N1)-np.dot(YDFA_ala_ase, N1)

ValueError: matrices are not aligned

其他尝试：

YDFA_ale_ase* 1.-N1-YDFA_ala_ase* N1

ValueError: operands could not be broadcast together with shapes (51) (1,1200)

但是：

print YDFA_ale_ase.shape, N1.shape

给我

(51,) (1, 1200)

Answer 1

打印数组的形状。请记住，Matlab 矩阵至少有 2 个 dims，而 NUMPY 可以是 1 甚至 0。很可能你正在尝试 dot a (n,) with a (1,m)。在 ( n,) 数组的右侧添加一个维度。 Y[:, None] 是最简单的方法。

http://wiki.scipy.org/NumPy_for_Matlab_Users

Matlab 到 Python：为什么我们会收到错误

Matlab to Python : why we are getting the error

python

numpy