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annotate scripts/linear-algebra/trace.m @ 4:b4df021f796c

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[project @ 1993-08-08 01:26:08 by jwe] Initial revision
author jwe
date Sun, 08 Aug 1993 01:26:08 +0000
parents
children 16a24e76d6e0
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1 function y = trace (x)
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3 # usage: trace (x)
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4 #
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5 # Returns the trace (the sum of the diagonal elements) of x.
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7 if (nargin != 1)
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8 error ("usage: trace (x)");
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9 endif
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11 y = sum (diag (x));
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13 endfunction