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# peaks

## PURPOSE

% Generate a function with lots of local maxima and minima. The function

## SYNOPSIS

function [X_out, Y_out, Z_out] = peaks (x, y)

## DESCRIPTION

% -*- texinfo -*-
% @deftypefn {Function File} {} peaks
% @deftypefnx {Function File} {} peaks (@var{n})
% @deftypefnx {Function File} {} peaks (@var{x}, @var{y})
% @deftypefnx {Function File} {@var{z} =} peaks (@dots{})
% @deftypefnx {Function File} {[@var{x}, @var{y}, @var{z}] =} peaks (@dots{})
% Generate a function with lots of local maxima and minima.  The function
% has the form
%
% @iftex
% @tex
% $f(x,y) = 3 (1 - x) ^ 2 e ^ {\left(-x^2 - (y+1)^2\right)} - 10 \left({x \over 5} - x^3 - y^5)\right) - {1 \over 3} e^{\left(-(x+1)^2 - y^2\right)}$
% @end tex
% @end iftex
% @ifnottex
% @verbatim
% f(x,y) = 3*(1-x)^2*exp(-x^2 - (y+1)^2) ...
%          - 10*(x/5 - x^3 - y^5)*exp(-x^2-y^2) ...
%          - 1/3*exp(-(x+1)^2 - y^2)
% @end verbatim
% @end ifnottex
%
% Called without a return argument, @code{peaks} plots the surface of the
% above function using @code{mesh}.  If @var{n} is a scalar, the @code{peaks}
% returns the values of the above function on a @var{n}-by-@var{n} mesh over
% the range @code{[-3,3]}.  The default value for @var{n} is 49.
%
% If @var{n} is a vector, then it represents the @var{x} and @var{y} values
% of the grid on which to calculate the above function.  The @var{x} and
% @var{y} values can be specified separately.
% @seealso{surf, mesh, meshgrid}
% @end deftypefn

## CROSS-REFERENCE INFORMATION

This function calls:
• meshgrid % Given vectors of @var{x} and @var{y} and @var{z} coordinates, and
• surf % Plot a surface given matrices @var{x}, and @var{y} from @code{meshgrid} and
This function is called by:

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