> How can I import a data file .txr in Maxima eviroment ?
I don't think Maxima has any standard functions for importing data
files, even from the most common formats (e.g. csv). And I don't know
what a txr file is.
You will probably have to either write your own Lisp program to parse
the txr format, or reformat the txr format into a format that Maxima
understands.
For example, in the case of a numerical csv file (comma separated
values), it can be as simple as putting a "[" at the beginning of the
file, a "]" at the end of the file, and replacing every line XXX,YYY,ZZZ
with [XXX,YYY,ZZZ]. It gets more complicated if the csv file contains
strings, since Maxima's quoting conventions and special characters are
different from Windows/CSV.
-s