Mathematica 9 is now available
Services & Resources / Wolfram Forums / MathGroup Archive
-----

MathGroup Archive 2008

[Date Index] [Thread Index] [Author Index]

Search the Archive

Bug in Interpolation for multi-d data?

  • To: mathgroup at smc.vnet.net
  • Subject: [mg85979] Bug in Interpolation for multi-d data?
  • From: oshaughn <oshaughn at northwestern.edu>
  • Date: Fri, 29 Feb 2008 06:24:30 -0500 (EST)

Hello,

Interpolation on multi-d data gives different answers depending on the
order in which the elements are *ordered* in the list.   As far as I
can tell, this is not documented.
The sorted element order seems to produce the right results.

Example 1:
dat = Flatten[
   Table[{{x, y}, Sin[x] Sin[2 y]}, {x, -3, 3, 0.1}, {y, -3, 3, 0.1}],
    1];
dat[[{1, 2, 3}]]
intp = Interpolation[dat];
ListPlot3D[Flatten /@ dat]
Plot3D[intp[x, y], {x, -3, 3}, {y, -3, 3}]

Example 2:
dat = Flatten[
   Table[{{x, y}, Sin[x] Sin[2 y]}, {y, -3, 3, 0.1}, {x, -3, 3, 0.1}],
    1];
dat[[{1, 2, 3}]]
intp = Interpolation[dat];
ListPlot3D[Flatten /@ dat]
Plot3D[intp[x, y], {x, -3, 3}, {y, -3, 3}]

Example 3:
dat = Flatten[
   Table[{{x, y}, Sin[x] Sin[2 y]}, {y, -3, 3, 0.1}, {x, -3, 3, 0.1}],
    1]//Sort;
dat[[{1, 2, 3}]]
intp = Interpolation[dat];
ListPlot3D[Flatten /@ dat]
Plot3D[intp[x, y], {x, -3, 3}, {y, -3, 3}]


Am I missing something obvious in the documentation?


  • Prev by Date: Mathematica 6.0.2 update
  • Next by Date: Word wrapping oddity/bug?
  • Previous by thread: Mathematica 6.0.2 update
  • Next by thread: Word wrapping oddity/bug?