1. Maxima digest, Vol 1 #166 - topic 1 (Webbooks)
I have taken a temporarily fix by using a function
definition for kdelta(i,j) as follows:
k_delta(i,j):=block([i,j,z:i-j],
if numberp(z) then
(if is(z=0) then 1 else 0)
elseif is(i=j) then 1 else 0)$
Outputs:
k_delta(1,1); 1
k_delta(1,0); 0
k_delta(0,1); 0
k_delta(true,true); 1
k_delta(true,false); 0
k_delta(false,true); 0
There are no error-traps for mixed entries such as:
k_delta(true, "hello") or k_delta(1,true) but I hope
that future upgrade of Maxima will supply this
function.
HuenYK
www.cahresearch.com ... the SA people
==================================
----- Original Message -----
From: <maxima-request at www>
To: <maxima@www.ma.utexas.edu>
Sent: Sunday, December 30, 2001 2:45 AM
Subject: Maxima digest, Vol 1 #167 - 10 msgs
>
> Today's Topics:
>
> 1. Maxima digest, Vol 1 #166 - topic 1 (Webbooks)
> 2. Re: emaxima problem (Jay Belanger)
> 3. PDE's and Maxima (Wolfgang Zocher)
> 4. Share directory work - notes, etc. (C Y)
> 5. Re: Strange bigfloat results (Raymond Toy)
> 6. Re: Strange bigfloat results (Richard Fateman)
> 7. integerp (a9104910@unet.univie.ac.at)
> 8. Re: integerp (Dan Stanger)
> 9. String functions (Dan Stanger)
> 10. Re: String functions (Richard Fateman)
>
> --__--__--
>
> Message: 1
> From: "Webbooks" <webbooks at singnet>
> To: <maxima@www.ma.utexas.edu>
> Date: Wed, 26 Dec 2001 22:31:45 +0800
> Subject: Maxima digest, Vol 1 #166 - topic 1
>
>
> 1. building maxima on autocad's autolisp (Richard J. Fateman)
> ------------------------------------------------------------------------
>
> OK, it is probably not a sound strategy to use AutoLISP for
> the purpose I mentioned. This is because it is an interpreter
> which would require access to the lisp source-code. My
> problem would be completely solved if I could roll a kdelta
> function definition for k_delta which performs exactly like that
> in Macsyma 2.2. Then I could supply this function to my existing
> ebooks and epapers in the appendix and recommend
> readers to download Maxima instead. Here is how k_delta
> function performs in Macsyma 2.2+:
>
> k_delta(1,1); 1
> k_delta(1,0); 0
> k_delta(0,1); 0
> k_delta(true,true); 1
> k_delta(true,false); 0
> k_delta(false,true); 0
>
> So far I have failed to emulate this exactly in a kdelta function
> using compare(i,j) with filters. Here is my kdelta function which
> works partially:
>
> kdelta(i,j):=block([args:args
[i,j]],(compare(i,j)-pos)*(compare(i,j)-neg))
> /((zero-neg)*(zero-pos))$
>
> kdelta(1,1); 1
> kdelta(1,0); 0
> kdelta(0,1); 0
> kdelta(true,true); 1
> kdelta(true,false); (PNZ - NEG) (PNZ - POS)/((ZERO - NEG) (ZERO -
POS) )
> kdelta(false,true); (PNZ - NEG) (PNZ - POS)/((ZERO - NEG) (ZERO -
POS) )
>
> HuenYK
> www.cahresearch.com