precalc_last-2

Hi Al.

thanks for addressing the precalculations!

i merged that into -uf, and everything looks good. but theres one
(minor) issue. consider

"""
spice
.MODEL TESTR RES (TC1=1m TC2=0 DEFW=1 RSH=1)
.options temperature=37
R1 1 0 TESTR(w=2, l=4)
.print tran r(R1)
.tran 0 1 .5 te=1342
.tran 2
.end
"""

(this is essentially tests/d_res.gc from -uf)

now, gnucap-uf says
#Time       r(R1)     
 0.         4.63      
 0.5        4.63      
 1.         4.63      
#Time       r(R1)     
 1.         4.63      
 1.5        4.63      
 2.         4.63      

and precalc_last-2 says
#Time       r(R1)     
 0.         4.63      
 0.5        4.63      
 1.         4.63      
#Time       r(R1)     
 1.         2.02      
 1.5        2.02      
 2.         2.02      

i think, both are correct somehow. and the manual does not seem to cover
this. is your implementation intentional? i cannot remember why i did it
the other way, and i might rather change it back.

cheers
felix