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%!%+
%\function{reverse}
%\synopsis{Reverse the elements of a 1-d array}
%\usage{Array_Type reverse (Array_Type A)}
%\description
% The \slfun{reverse} function reverses the elements of a 1-d array and
% returns the result.
%\seealso{shift}
%!%-
public define reverse (a)
{
variable i = length (a);
if (i <= 1)
return a;
i--;
__tmp(a)[[i:0:-1]];
}
%!%+
%\function{shift}
%\synopsis{Shift the elements of a 1-d array}
%\usage{Array_Type shift (Array_Type A, Int_Type n)}
%\description
% The \slfun{shift} function shifts the elements of an array by a specified amount
% and returns the result. If \exmp{n} is positive, the ith element of the array
% will be shifted to the position \exmp{i-n} of the array. Elements for
% which \exmp{i-n} is less than 0 will be moved to the end of the array.
%\example
%#v+
% A = [1,2,3,4,5,6,7,8,9];
% B = shift (A, 3); % ==> B = [4,5,6,7,8,9,1,2,3];
% C = shift (A, -1); % ==> C = [9,1,2,3,4,5,6,7,8];
%#v-
%\notes
% It many ways \exmp{rotate} would be a better name for this function.
%\seealso{reverse, transpose}
%!%-
public define shift (x, n)
{
variable len = length(x);
variable i = [0:len-1];
% allow n to be negative and large
n = len + n mod len;
return x[(i + n)mod len];
}
provide ("arrayfuns");
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