Re: n-dim product

[Francesco Potorti`]

>> If I have two vectors and want to produce a matrix of all the possible
>> products of their elements, I just multiply them:
>>
>> octave> x=1:3; y=1:4; x'*y
>> ans =
>>
>>    1    2    3    4
>>    2    4    6    8
>>    3    6    9   12
>>
>> How to generalise this simple operation to multiple dimensions?
>
>the easy way:
>
>[xx, yy, zz] = ndgrid (x, y, z);
>xx .* yy .* zz
>
>this may be faster:
>reshape ((x'*y)(:) * z, [length(x), length(y), length(z)])
>
>(x, y, z are row vectors)

Thank you!

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