Re: Determinant function in Mathematica
- To: mathgroup at yoda.physics.unc.edu
- Subject: Re: Determinant function in Mathematica
- From: jpw at vax135.att.com
- Date: Fri, 10 Apr 92 10:59:30 edt
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 ...)
Mathematica (ULTRIX) 1.2 (November 15, 1989) [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 Wolfram Research Inc.
-- X11 windows 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.
0.05 Second
0.133333 Second
0.383333 Second
1.46667 Second
8.58333 Second
65.5833 Second
the original mail of Oliver Gloor follows ...
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Date: Thu, 9 Apr 92 13:53:34 +0200
To: mathgroup at yoda.physics.unc.edu
Subject: Re: Determinant function in Mathematica
From: gloor at inf.ethz.ch
Maybe you have to less memory, for me it works pretty well up to 7x7 - determinants:
------------------------------
Mathematica 2.0 for SPARC
Copyright 1988-91 Wolfram Research, Inc.
Temporary license: expiration date is 30 Jun 1992.
-- X11 windows 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
0.05 Second
0.233333 Second
0.9 Second
5.95 Second
74.1 Second
2585.98 Second
-----------------------------
Oliver Gloor,
gloor at inf.ethz.ch