Re: Getting coordinates of array member

*To*: mathgroup at smc.vnet.net*Subject*: [mg26292] Re: [mg26247] Getting coordinates of array member*From*: BobHanlon at aol.com*Date*: Sun, 10 Dec 2000 00:20:02 -0500 (EST)*Sender*: owner-wri-mathgroup at wolfram.com

GetPos[{x_, y_}, mat_List] := mat[[y, x]]; GetCoord[value_, mat_List] := Reverse /@ Position[mat, value]; mat = Partition[Range[9], 3]; GetPos[{1, 3}, mat] 7 GetCoord[%, mat] {{1, 3}} This is a list of coordinates since, in general, there can be more than one coordinate with the specified value. For example, mat = IdentityMatrix[3]; GetCoord[1, mat] {{1, 1}, {2, 2}, {3, 3}} Bob Hanlon In a message dated 12/6/00 3:08:08 AM, stephhebert at yourpants~videotron.ca writes: >Ok, let's say I have this > > 1 2 3 > ----------- > 1| 1 2 3 > 2| 4 5 6 > 3| 7 8 9 > >A 3x3 matrice or array. Each number in the array represents its' position >from top left to bottom right. > >What I need to do is: > >Find what position 1,3 is. Just by looking at the array, we find that >7 is >the answer. > >Find what are the coordinates of 7. Again just by looking at the array >we >see that the answer is 1,3 > >I need to come up with a simplu function that will return these. > >pos = GetPos(x,y) > >coord = GetCoord(pos) >