Finding local maxima's and minima's of a curve

%output = fpeak(x,y,s,range)
% x and y are the data
% s: is a scallar and determines the sensitivity of the function, the
% default (minimum) value is 1.
% Range: is the interval to find local maxima and minima and is
% optional, it has four elements: [x_min x_max y_min y_max]
% output: is the xy position of local maxima's and minima's
% SEE ALSO findpeaks
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% Author: Geng Jun, Dec 09, 2003
% Email: dr.gengjun@126.com
% Editted by: Farhad VISHKAEE, 23 May, 2010
% Email: f.vishkaee@gmail.com
% LinkedIn: http://www.linkedin.com/pub/farhad-vishkaee/33/191/40a
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