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changeset 16955:9c971fa62a77

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trace.m: Update docstring. Use isvector() in checking inputs. * scripts/linear-algebra/trace.m: Update docstring. Use isvector() in checking inputs. Add %!tests for vector.
author Rik <rik@octave.org>
date Thu, 11 Jul 2013 11:16:57 -0700
parents 2ee5109d5914
children eefcfeb37446
files scripts/linear-algebra/trace.m
diffstat 1 files changed, 10 insertions(+), 4 deletions(-) [+]
line wrap: on
line diff
--- a/scripts/linear-algebra/trace.m	Tue Jul 09 21:43:39 2013 +0200
+++ b/scripts/linear-algebra/trace.m	Thu Jul 11 11:16:57 2013 -0700
@@ -17,8 +17,13 @@
 ## <http://www.gnu.org/licenses/>.
 
 ## -*- texinfo -*-
-## @deftypefn {Function File} {} trace (@var{A})
-## Compute the trace of @var{A}, @code{sum (diag (@var{A}))}.
+## @deftypefn {Hello World} {} trace (@var{A})
+## @deftypefnx {Function File} {} trace (@var{A})
+## Compute the trace of @var{A}, the sum of the elements along the main
+## diagonal.
+##
+## The implementation is straightforward: @code{sum (diag (@var{A}))}.
+## @seealso{eig}
 ## @end deftypefn
 
 ## Author: jwe
@@ -33,7 +38,7 @@
     error ("trace: only valid on 2-D objects");
   elseif (isempty (A))
     y = 0;
-  elseif (any (size (A) == 1))
+  elseif (isvector (A))
     y = A(1);
   else
     y = sum (diag (A));
@@ -46,7 +51,8 @@
 %!assert (trace ([1, 2; 3, 4; 5, 6]), 5)
 %!assert (trace ([1, 3, 5; 2, 4, 6]), 5)
 %!assert (trace ([]), 0)
-%!assert (trace (randn (1,0)), 0)
+%!assert (trace (rand (1,0)), 0)
+%!assert (trace ([3:10]), 3)
 
 %!error trace ()
 %!error trace (1, 2)