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fmin | Examples See Also |
Minimize a function of one variable
x = fmin('fun
',x1,x2) x = fmin('fun
',x1,x2,options) x = fmin('fun
',x1,x2,options,P1,P2, ...) [x,options] = fmin(...)
x = fmin('fun
',x1,x2)
returns a value of x
which is a local minimizer of fun(x)
in the interval .
x = fmin('fun
',x1,x2,options)
does the same as the above, but uses options
control parameters.
x = fmin('
fun
',x1,x2,options,P1,P2,...)
does the same as the above, but passes arguments to the objective function, fun(x,P1,P2,...)
. Pass an empty matrix for options
to use the default value.
[x,options] = fmin(...)
returns, in options(10)
, a count of the number of steps taken.
fmin('cos',3,4)
computes to a few decimal places.
fmin('cos',3,4,[1,1.e-12])
displays the steps taken to compute to 12 decimal places.
To find the minimum of the function on the interval (0,
2), write an M-file called f.m
.
function y = f(x) y = x.^3-2*x-5;Then invoke
fmin
with
x = fmin('f'The result is,
0,
2)
x = 0.8165The value of the function at the minimum is
y = f(x) y = -6.0887The algorithm is based on golden section search and parabolic interpolation. A Fortran program implementing the same algorithms is given in [1].
fmins
Minimize a function of several variables
fzero
Zero of a function of one variable
foptions
in the Optimization Toolbox (or type help foptions
).