
Re: Re; Reordering lists?!
Posted:
Jul 30, 1996 3:16 AM


In article <4thaug$j6e@dragonfly.wolfram.com>, abindon@gpu.srv.ualberta.ca (Andre and Alain) wrote:
> Hey! I have a list of Numbers, 1 to 4, and wish to rescale them so > that 1 replkaces 4 and 3 replaces 2 and 2 replaces 3 etc. I made a little > code to do this on an element per element basis and it doesn't seem to do > it! Could someone let me know what I'm doing wrong or whether it's a Mma > problem? Thanks > > <The original list> > > gsub=Flatten[ColumnTake[gcsq,{4}]] > {2, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 2, 2, 1, 1, 3, 1, 1, 2, 1, 2, 1, 2, 1, 1, > 1, 1, 2, 1, 2, 1, 3, 1, > 2, 2, 1, 2, 1, 2, 3, 2, 4, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 2, 1, 2, 1, 2, > 3, 2, 2, 2, 1, 2, 1, > 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 2, 2, 2, 1} > > <Frequencies of the list> > > Frequencies[gsub] > {{42, 1}, {34, 2}, {4, 3}, {1, 4}} > > <The code that replaces them> > > Do[If[gsub[[n]]==1,gsub[[n]]=4] > If[gsub[[n]]==2,gsub[[n]]=3] > If[gsub[[n]]==3,gsub[[n]]=2] > If[gsub[[n]]==4,gsub[[n]]=1], > {n,1,Length[gsub]}] > > <It doesn't work properly?!> > > Frequencies[gsub] > {{43, 1}, {38, 2}} > > Of course the new list frequencies should be exactly opposite than the first > one. Help please?! > Thanks > Andre Bindon > Ablerta Hospital Edmonton
You might want to replace the OR function "" by an ELSE functoin ","
Do[If[gsub[[n]]==1,gsub[[n]]=4, If[gsub[[n]]==2,gsub[[n]]=3, If[gsub[[n]]==3,gsub[[n]]=2, If[gsub[[n]]==4,gsub[[n]]=1] ] ] ], {n,1,Length[gsub]}]
You also can do the following:
" Map[ 5#&, gsub] " which is the same as " 5#&/@gsub "
Wjr
 }. `\ I only exist in interaction

