how can you pass values to variables in an an array of functions?

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Leonard 2014-3-22

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评论： David Young 2014-3-24

I am trying to make a movie of the solutions to the heat equation for various values of a parameter in the coefficients . I want to create an array for the fourier coefficients of the solution. How can I define an 'array function' ? does this idea exist.

apologies if theis is a duplicate question. couldn't find this answer anywhere.

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Leonard 2014-3-22

what if the function which defined each cell was more complicated than an exponent?

so basically passing a value to a parameter (variable) in multiple cells in an array is something everyone should avoid?

Jan 2014-3-22

@Leonard: If you have a more complicated function, you create a function file, which can be as complicated as you want.

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per isakson 2014-3-22

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编辑：per isakson 2014-3-22

在 MATLAB Online 中打开

Playing with anonymous functions in combination with cellfun

    fh{1}=@(x) x.*x;
    fh{2}=@(x) x.*x.*x;
    fh{3}=@(x) x.*x.*x.*x;
    fh{4}=@(x) sin(x);
    fh{5}=@(x) cos(x);
    foo = @(z) cellfun( @(f,x) f(x), fh, repmat({z},size(fh)), 'uni', false);
    foo(2)

returns

    ans = 
        [4]    [8]    [16]    [0.9093]    [-0.4161]

However, those are cell arrays. Matlab doesn't support ordinary arrays of anonymous functions.

Or a little better

    foo = @(z) cellfun( @(f,x) f(x), fh, repmat({z},size(fh)), 'uni', true);
    foo(2)

returns

    ans =
        4.0000    8.0000   16.0000    0.9093   -0.4161

which is an array of doubles.

I guess that what you want is a Functional programming languages

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per isakson 2014-3-23

编辑：per isakson 2014-3-23

An array with ten identical functions might not be useful.

However, anonymous functions are powerful and it takes some experiments to learn how to use them. "[...] any votes on that idea?" I vote for keeping the post. I contributed an experiment.

David Young 2014-3-24

Yes, building the 10 anonymous functions is being overcomplicated. Almost certainly you can do what you want just by passing vector arguments to ordinary functions. I'd say keep the post - there are many less interesting and less useful threads here.

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