On 1/23/07, Tommy Li <tommycli at ucla.edu> wrote:
> > (%o5) ['diff((a*%e^(-%i*beta*x)),y,1),-'diff((a*%e^(-%i*beta*x)),x,1),0]
> > (%i6) %,diff;
> > (%o6) [0,%i*a*beta*%e^(-%i*beta*x),0]
> They key seems to be %i6. What is the secret of the comma and diff? Why
> does that make it evaluate the diffs? I can't seem to find any notes on
> the comma in the manual.
'diff is a so-called noun -- essentially a function which isn't evaluated.
ev(foo, diff) causes 'diff nouns to be evaluated if present, ev(foo, nouns)
causes all nouns to be evaluated. %, diff is an abbreviation for ev(%, diff).
There is an attempt to explain this stuff in the manual under ev --
try ? ev at the input prompt.
Hope this helps, & thanks for your interest in Maxima.
Robert Dodier