Finding a summation of a two variable function keeping one parameter constant.

I need to do a summation of a function f(x,n) such that x remains as a variable in the process and n varies from 1 to N ( like 1:100 or something).

So I need f(x,1) + f(x,2) + f(x,3) ........... + f(x,N) in a variable SUM, such that SUM could work like a function handle, with x alone as its argument.

f(x,n) is any arbitrary function.

How do I do this in MATLAB?

Answer 1

[Michael Soskind]

Sushanth,

The method for doing this depends on your function f(x,N).

If this function works with vectors, then the easiest function for this would be something in the form:

N = 1:100;
sum_function = @(x) sum(f(x, N));       % Assuming f(x,N) can take a vector N and is already defined

Then, calling sum_function(10) would provide the summation with x = 10.

Alternatively, you could make a function that only accepts X, and a range to sum over, and go through a for loop summing the values over that range. However, that is up to you.

Hope that helps,

Michael