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[Bug fortran/32512] efficiency of RESHAPE and SPREAD



------- Comment #3 from burnus at gcc dot gnu dot org  2007-06-26 11:54 -------
Just to show how much time can be saved, I compared the speed with different
compilers (on x86-64/Linux):

gfortran sunstudio12  ifort9.1/10 open64  NAGf95  g95
-------------------------------------------------------
 0.024   0.02575      0.024       0.024   0.03    0.028 (1)
 0.028   0.025365     0.024       0.024   0.03    0.028 (2)
 6.12    0.025514     2.420       0.024   2.59   21.373 (3)
10.47    4.307007   18.4371       2.616  11.58   10.660 (4)
-------------------------------------------------------
(1) matrix_op(a), (2) matrix_op(transpose(a))
(3) matrix_op(reshape(b,shape=(/n,n+1/)))
(4) matrix_op(spread(c,dim=1,ncopies=n))

Thus especially RESHAPE has a huge potential.


-- 

burnus at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |burnus at gcc dot gnu dot
                   |                            |org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2007-06-26 11:54:21
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32512


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