Re: Speed of writing in Mathematica 3.01
- To: mathgroup@smc.vnet.net
- Subject: [mg11770] Re: Speed of writing in Mathematica 3.01
- From: Rolf Mertig <rolf@mertig.com>
- Date: Sat, 28 Mar 1998 00:25:10 -0500
- Organization: Mertig Research & Consulting
- References: <6fd5ag$6aq@smc.vnet.net>
You are doing nothing wrong (except maybe not running Linux on your
Mac).
On my a antique 25 Mhz NeXTStation (1991), running the (unfortunately)
very last official
release of Mathematica for NeXTStep (if there are more people, like me,
who would actually
*pay* for the next version of Mathematica for NeXTStep, then speak up to
WRI, please!),
and a simple Linux-Box (Pentium 120 MHz):
In[1]:= $Version
Out[1]= NeXT 3.0 (April 15, 1997)
In[2]:= a = Table[i,{i,1001}];
In[3]:= Timing[
filename="test.ascii";
output=OpenWrite[filename];
Do[Write[output,a[[i]]];,{i,1,1001}];
Close[output];]
Out[3]= {1.46824 Second, Null}
In[1]:= $Version
Out[1]= Linux 3.0 (April 25, 1997)
In[2]:= a = Table[i,{i,1001}];
In[3]:= Timing[
filename="test.ascii";
output=OpenWrite[filename];
Do[Write[output,a[[i]]];,{i,1,1001}];
Close[output];]
Out[3]= {0.33 Second, Null}
Rolf Mertig
Mathematica programming, training & consulting http://www.mertig.com
James Bridges wrote:
> Am I doing something wrong or is it supposed to take orders of magnitude
> longer than is reasonable to write out a simple ASCII file from
> Mathematica? Consider this simple test:
>
> In[7]:=
> a=Table [i,{i,1,1001}];
>
> In[8]:=
> Timing[
> filename="Macintosh HD:test.ascii";
> output=OpenWrite[filename];
> Do[
> Write[output,a[[i]]];
> ,{i,1,1001}];
> Close[output];
> ]
>
> Out[8]=
> {23.4 Second,Null}
>
> 23 seconds to write 1001 integers?! On a 233MHz G3! Everything else is
> whiff-bam fast, but writing is glacial. Now this is a simplified
> example of what I need to do but it contains one of the factors, namely
> that I have to individually write out elements of a list, hence the Do
> loop. Any hints?
>
> James Bridges
>
> --
> James Bridges
> Cleveland, OH