Mathematica 9 is now available
Student Support Forum
Student Support Forum > General > > "Help with creating matrix from another matrix"

Post Reply:
Email Address:

Please send email when my message is replied to.

Url (optional):
Message: view original message?
Attachment (optional):
Please answer this:2+2 =

Original Message (ID '429836') By Bill Simpson:
In Response To 'Re: Re: Help with creating matrix from another ...' --------- Small corrections and slightly simpler. Note: uses a,b,c matrix names because B,C are used by Mathematica. c = Table[ xp = Map[Last, Position[a, x]]; yp = Map[Last, Position[a, y]]; If[xp=={} || yp=={} || Length[xp]≠Length[yp], 0, Plus@@Map[b[[Sequence@@#]]&, Transpose[{xp,yp}]] ], {y, 150}, {x, 150}]