
Re: altering each member of a list that matches a certain pattern
Posted:
Jun 21, 2012 5:23 AM


Hello,
the functional approach (Method 1) is beautiful, a simple rule based approach would be
list /. x_Integer :> SuperStar[x] /; x > 9
Your Method 2 looks a little bit complex for the simple task to be done.
Best,
Christoph
On 06/20/2012 09:51 AM, Jason Ebaugh wrote: > Good people, > > > I need to alter each member of a list that matches a certain pattern. > However, I need the whole list back, in its original order. > So Cases[] on its own doesn't do the trick. > > Here is a toy example that is analogous to my real problem: > Put an asterisk on each value that is 10 or greater in the following list. > > list = RandomSample[Range[20], 20] > > Out[1]= {19, 16, 5, 13, 10, 20, 1, 3, 18, 8, 9, 6, 12, 7, 4, 15, 11, 14, 2, 17} > > I came up with two ways to do this. > However, I feel like I may be missing a simpler, single function way to do this. > > Method 1: > If[#> 9, SuperStar[#], #]& /@ list > > Out[2]= {SuperStar[19], SuperStar[16], 5, SuperStar[13], SuperStar[10], > SuperStar[20], 1, 3, SuperStar[18], 8, 9, 6, SuperStar[12], 7, 4, > SuperStar[15], SuperStar[11], SuperStar[14], 2, SuperStar[17]} > > > Method 2: > ReplacePart[list, > Table[{Position[list, x_ /; x> 9][[i, 1]] > > Map[SuperStar, Cases[list, x_ /; x> 9]][[i]]}, {i, > Length[Cases[list, x_ /; x> 9]]}] // Flatten] > > Out[3]= {SuperStar[19], SuperStar[16], 5, SuperStar[13], SuperStar[10], > SuperStar[20], 1, 3, SuperStar[18], 8, 9, 6, SuperStar[12], 7, 4, > SuperStar[15], SuperStar[11], SuperStar[14], 2, SuperStar[17]} > > > Am I missing a more straightforward way to do this? > > > > Thanks, > Jason > > > Jason Ebaugh >

