MATLAB: Problem of function handles, thx

function handleMATLAB

for instance,

parms=ones(2,1);

myfunc = @(parms) X.*parms(1)+Y.*parms(1);

I can directly indicate 'myfunc' in 'fmincon'. [parms,favl]=fmincon(myfunc,parms,….);

However, if I want to separately write 'myfunc' in a function script and then quote it. [parms,favl]=fmincon(myfunc,parms,….); the 'fmincon' will report 'Not enough input in myfunc'.

X and Y are variables stored in workspace, they are not unknown parameters, only parms(1) and parms(2) required estimation.

anyone can tell me how to solve this problem? many thanks!

Best Answer

You need an @ before myfunc, otherwise it tries to evaluate it:

@myfunc % reference to function myfunc; do not evaluate
myfunc % when myfunc is its own file tries to run it
myfunc % when myfunc is a function handle (variable), then myfunc is already a reference to whatever

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