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Re: Unwrap list of angles

  • To: mathgroup at smc.vnet.net
  • Subject: [mg73291] Re: [mg73262] Unwrap list of angles
  • From: gardyloo <gardyloo at mail.wsu.edu>
  • Date: Fri, 9 Feb 2007 23:39:28 -0500 (EST)
  • References: <200702090718.CAA18382@smc.vnet.net>

Hi, Ben,

   I ended up writing a version of this a while ago. Here's the 
definition I use. The first is for a list of one dimension; it's used in 
the second definition (since I usually deal with lists of two dimensions 
where the second element in the ordered pairs is the phase.

UnwrapPhase[list_ /; Length[Dimensions[list]] == 1] :=

      Module[{newTest,

          lC = 

               Mod[

                   ListCorrelate[{-1, 1}, list], Pi, -Pi/2]}, newTest[1] = list[[1]];

    newTest[i_] := newTest[i] = newTest[i - 1] + lC[[i - 1]];

    newTest[#] & /@ Range[Length[list]]]

UnwrapPhase[list:{{_,_}..} ]:=

  Transpose[

    {

      list[[All, 1]],

      UnwrapPhase[list[[All,-1]]]

      }

    ]




   Hope that helps!

                 C.O.

ben wrote:
> Dear all
>
> I am looking for a Mathematica-analogue of the unwrap function in another system:
> I have a list of angles and want to add multiples of 2*pi to them, so
> that there
> are no 'jumps' between subsequent entries.
> Is there a ready-made function?
>
> Bye
> Ben
>
>
>
>   

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