[Maxima] fpprec and output precision

Peter Gustafson petegus at spaceshipone.engin.umich.edu
Wed Jun 28 15:31:04 CDT 2006

Hi all, 

As a follow up to something that was asked in May 2005 but not answered
(as far as I can tell).  fpprec doesn't seem to provide consistent
output, particularly with scientific notation and tex().  Please review
these examples of what I consider to be strange behavior.

(%i75) fpprec:4;
(%o75)                                 4
(%i76) tex(5.0011613);
(%o76)                               false
(%i77) tex(5.0011613e-5);
$$5.0011613 \times 10^{-5}$$
(%o77)                               false
(%i78) tex(5.0011613e5);
(%o78)                               false
(%i79) 5.0011613e5;
(%o79)                              500116.
(%i80) 5.0011613e-5;
(%o80)                             5.0012E-5
(%i81) 5.0011613;
(%o81)                               5.001

Is there a way to have consistent output, and by consistent I mean
report a specific number of significant figures in all output,
regardless of the input style?  Perhaps I am making assumptions about
fpprec, and there is something else available for this purpose?  Thanks
a bunch,


Below is the previous question:
Like this:
(%i2360) FPPREC:6;

(%o2360)                               6
(%i2361) tex(float(1/3));

(%o2361)                             FALSE
(%i2362) tex(float(1/3*10^-24));

$$3.3333333333333335 \times 10^{-25}$$
(%o2362)                             FALSE
(%i2363) tex(float(1/3*10^-2));

(%o2363)                             FALSE

The output of (%i2362) is not wanted. Why the setting
of FPPREC doesn't work when the value is too little?

(%i2364) float(1/3*10^-24);

(%o2364)                          3.33333E-25
It works without "tex"!

Is there any other way to make the "tex"ed value to be
shorter. It is for the convenience of reading.

Thanks for consideration.

YC Zou

More information about the Maxima mailing list