Re: a problem about mathematica output
- To: mathgroup at smc.vnet.net
- Subject: [mg82441] Re: a problem about mathematica output
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Sat, 20 Oct 2007 05:54:20 -0400 (EDT)
- Organization: The Open University, Milton Keynes, UK
- References: <ff9rli$4nj$1@smc.vnet.net>
qwer wrote:
> I have a puzzle when using mathematica, I want to out put my resuts to
> a .dat file ,but I do not know how to control the digital, for
> example:
>
> the mathematica code is
>
> f[x_]:=NIntegrate[Sin[y]/y,{y,0,x}];
> OpenWrite["xx.dat",FormatType->TextForm];
> Do[Write["xx.dat",N[x,4]," ",N[f[x],4]],{x,0.001,1,0.05}];
> Close["xx.dat"];
>
> then in xx.dat you can find
> 0 0.
> 0.05 0.0499931
> 0.1 0.0999445
> 0.15 0.149813
> 0.2 0.199556
> 0.25 0.249134
> .
> .
> but I want it can be written in the form
> 0.000 0.000
> 0.050 0.050
> 0.100 0.100
> 0.150 0.150
> 0.200 0.200
> 0.250 0.249
> .
> .
> It will be look much better!
Use *NumberForm* to get a precise control over how many significant
figures are displayed, how many digits after the decimal point, or
padding characters and the like.
f[x_] := NIntegrate[Sin[y]/y, {y, 0, x}];
OpenWrite["xx.dat", FormatType -> TextForm];
Do[Write["xx.dat", NumberForm[x, {3, 3}], " ",
NumberForm[f[x], {3, 3}]], {x, 0.001, 1, 0.05}];
Close["xx.dat"];
will write
0.001 0.001
0.051 0.051
0.101 0.101
0.151 0.151
0.201 0.201
0.251 0.250
0.301 0.299
0.351 0.349
... ...
Regards,
--
Jean-Marc