Am Donnerstag, den 11.06.2009, 19:17 -0400 schrieb Raymond Toy:
> Dieter Kaiser wrote:
> > Am Donnerstag, den 11.06.2009, 18:36 -0400 schrieb Raymond Toy:
> >
> >> Dieter Kaiser wrote:
> >>
> >>> I would like to suggest to improve the Maxima user function apropos.
> >>> This is the last result of some work to get a working function apropos:
> >>>
> >>> ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
> >>>
> >>> ;;; Utility function to filter a list LST with a function FN
> >>> ;;; e.g. (filter #'(lambda(x) (if (oddp x) x)) '(1 2 3 4 5 6 7)) --> (1
> >>> 3 5 7)
> >>>
> >>>
> >> I think this is called remove-if-not. :-)
Hello Ray,
at first I have thought that the function filter is identical to
remove-if-not. But that is not true.
filter accepts a function which does not only a test, but returns a
value. These values are collected into a new list. I have used this
functionality to change %-ed functions to $-ed functions.
Dieter Kaiser