Explain this behavior?

[Jeremy Teitelbaum <jeremy@uic.edu>]

Dear pari users,
can anyone explain this to me?  The variable l1 is computed
in a function.   It contains a matrix with rational entries.
THe command mathnf(l1) fails; however, typing "l1" followed
by mathnf(%) works fine.  Here is what I mean:

? mathnf(l1)
  ***   not an integer argument in an arithmetic function
? l1
%84 = 
[-31/37 27 14 -1 0 0 48/37 0 0 -8 0 0]

[-62/37 1 0 0 -1 0 96/37 0 0 0 -8 0]

[-93/37 0 1 0 0 -1 144/37 0 0 0 0 -8]

[-24/37 0 0 4 0 0 -7/37 27 14 -5 0 0]

[-48/37 0 0 0 4 0 -14/37 1 0 0 -5 0]

[-72/37 0 0 0 0 4 -21/37 0 1 0 0 -5]

? mathnf(%)
%85 = 
[37 27 14 9 16 77/37]

[0 1 0 0 0 6/37]

[0 0 1 0 0 9/37]

[0 0 0 1 0 25/37]

[0 0 0 0 1 13/37]

[0 0 0 0 0 1/37]

Tips would be appreciated.

Jeremy T>








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+ Jeremy T. Teitelbaum, Professor of Mathematics
+ Department of Mathematics, Statistics and Computer Science (M/C 249)
+ University of Illinois at Chicago
+ SEO 322 / 851 S. Morgan Street
+ Chicago, IL 60607
+ jeremy@uic.edu                             http://raphael.math.uic.edu/~jeremy
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