如何在Mathematica中将列向量乘以行向量？

Question

我想将列向量中的每个值乘以相同的向量，但转置为行。输出应该是一个乘法表矩阵。 Like the third example in this picture。

I tried multiplying a column vector by its transposed form but Mathematica only gives me this which is not a Matrix.

Answer 1

布莱恩，

您需要使用Dot，而不是Times。参见docs。

m = {{a}, {b}, {c}}
m.Transpose[m]

  

{{{a ^ 2，a b，a c}，{a b，b ^ 2，b c}，{a c，b c，c ^ 2}}