Re: Determinant function in Mathematica
- To: mathgroup at yoda.physics.unc.edu
- Subject: Re: Determinant function in Mathematica
- From: "Lawrence M. Seiford, IEOR, UMass, 413/545-1658." <SEIFORD at ecs.umass.edu>
- Date: Mon, 13 Apr 1992 18:06 -0500
jpw at vax135.att.com writes:
>i repeated the exact code from Oliver Gloor (gloor at inf.ethz.ch) on
>Mathematica 1.2 under ULTRIX (3.x) running on a microVAX III (~3-4 MVUPs)
>and got the following timings (16 MB of real memory, 64 MB of swap)
>the timing difference are better than an order of magnitude faster on
>the microVAX versus the SPARC (which i find somewhat puzzling ...)
The difference isn't due to the machine but rather the version of Mathematica
used. As shown below--1.2 is considerably faster than 2.0!...larry
Mathematica (DEC RISC) 1.2 (January 24, 1990) [With pre-loaded data]
by S. Wolfram, D. Grayson, R. Maeder, H. Cejtin,
S. Omohundro, D. Ballman and J. Keiper
with I. Rivin and D. Withoff
Copyright 1988,1989,1990 Wolfram Research Inc.
-- Terminal graphics initialized --
In[1]:= a[n_] := Table[ StringJoin["a",ToString[i],ToString[j]], {i,1,n}
,{j,1,n}];
In[2]:= Do[ Print[ First[ Timing[ Det[ a[t]]]]], {t,1,7}]
0.
0.0166667 Second
0.0166667 Second
0.0666667 Second
0.216667 Second
1.25 Second
9.78333 Second
In[3]:= Quit
Mathematica 2.0 for DEC RISC
Copyright 1988-91 Wolfram Research, Inc.
Cannot connect to license server. Retrying.
-- Terminal graphics initialized --
In[1]:= a[n_] := Table[ StringJoin["a",ToString[i],ToString[j]], {i,1,n}
,{j,1,n}];
In[2]:= Do[ Print[ First[ Timing[ Det[ a[t]]]]], {t,1,7}]
0.0166667 Second
0.0666667 Second
0.266667 Second
1. Second
5.76667 Second
70.65 Second
Interrupt> a
[Sorry, I couldn't afford the 45 minutes!]