Fair enough - it substitutes rather than terminating a script due to an
error.
Don
On 11/19/2015 6:02 AM, Linda A Alvord wrote:
It doesn't preserve the concept of _%_
But it does serve as an interesting mask for making images:
load 'viewmat'
L=:(-_),(-2%~1-~%:5),0,(2%~1-~%:5),_
f=:0:@% ::1:"0/~
[M=:f L
[A=: */~i.5
[GRB=:|.255*1 0 2{"1 #:i.8
[PAL=:GRB,3#0
PAL viewmat A
PAL viewmat (16*f L)>.A
Linda
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Don Kelly
Sent: Thursday, November 19, 2015 1:12 AM
To: [email protected]
Subject: Re: [Jprogramming] Why is subtraction and division of rational
numbers so hard?
How is this "why" ? it appears that all it does is substitute a number (in
this case 1) rather than have NaN. I can see this as a way to avoid a NaN
error by flagging it without stopping execution.- not as an explanation for
the NaN using __%__
*ff=: % :: 9:*
__ ff __
9
3 ff 2
1.5
also works with
*ff2=: - :: 9:*
__ ff2 __
9
4 ff2 1
3
Don
On 11/18/2015 8:28 PM, Linda A Alvord wrote:
Here's why...
f=:0:@% ::1:
_ f _
Linda
1
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Raul
Miller
Sent: Monday, November 16, 2015 1:46 PM
To: Programming forum
Subject: Re: [Jprogramming] Why is subtraction and division of rational
numbers so hard?
You might also like to see:
L=:(-_),(-2%~1-~%:5),0,(2%~1-~%:5),_
0:@% ::1:"0/~ L
1 0 0 0 1
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
1 0 0 0 1
Thanks,
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