Math Is Fun Forum

onako

Member

Registered: 2010-03-28

Posts: 43

Find the derivative of this function

Suppose you're given a function

where ecl(x_i, x_j) stands for the Euclidean distance between points x_i and  x_j (1D or 2D).
(s_{ij} and x_j are constants)
How to find the derivative of the above with respect to x_i.
The sum sign and the dimensionality are the problem for me.
Any help on how to solve this is appreciated.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: Find the derivative of this function

hi onako

So you can stick a 'sigma' back in for the sum, and I think that should do it.

Hope that helps,

Bob

Last edited by Bob (2011-12-27 02:28:32)

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