help for data interpolation

cxcxcx0505 · November 1, 2010, 06:11

I have data like this.matrix x,y and z.They can be plot to get a 3D surface.But, the data is only 8X7 matrix.I need to interpolate so that these there matrix become 80X70.How can I do the interpolation?Do anyone know?
Thanks!

[matrix X] (8X7)
-2.000000 -0.253290 2.530883 4.408495 6.484675 8.603029 12.000000
-2.000000 -0.198017 2.492032 4.287214 6.286022 8.542624 12.000000
-2.000000 0.055891 2.917745 4.910930 6.760385 9.110679 12.000000
-2.000000 0.440220 3.007800 5.067369 7.184489 9.370805 12.000000
-2.000000 0.649703 3.220592 5.550846 7.136382 9.419947 12.000000
-2.000000 0.766721 2.901661 5.422805 7.490025 9.714287 12.000000
-2.000000 0.400457 2.592794 5.489784 7.235743 9.964797 12.000000
-2.000000 0.396081 2.601213 5.297624 7.349845 9.914467 12.000000

[matrix Y] (8X7)
5.000000 5.000000 5.000000 5.000000 5.000000 5.000000 5.000000
0.586906 1.572462 2.538616 3.316567 2.796196 3.542882 1.551908
0.078708 0.608548 1.065732 1.461480 1.618063 1.354950 0.427768
-0.010383 -0.054167 0.823114 1.225726 1.369016 1.061109 0.239242
0.170133 0.214137 0.785628 0.945448 0.952803 0.750114 0.462212
0.232092 0.366816 0.908057 1.144984 1.088131 1.441083 0.723935
0.368313 0.745600 1.161940 1.393370 1.675171 1.795770 1.007748
5.000000 5.000000 5.000000 5.000000 5.000000 5.000000 5.000000

[matrix Z] (8X7)
-9.000000 -9.000000 -9.000000 -9.000000 -9.000000 -9.000000 -9.000000
-10.935015 -11.084483 -9.977332 -9.563093 -9.508658 -9.492408 -9.727265
-11.472939 -11.769012 -11.404871 -10.792594 -10.297023 -10.676209 -10.705359
-13.393990 -13.516353 -13.449236 -13.169214 -12.843448 -13.128858 -13.073084
-15.330998 -15.373059 -15.417483 -15.363019 -14.924627 -15.198594 -15.017660
-17.271636 -17.272911 -17.276973 -16.968769 -16.716547 -17.123834 -16.837157
-18.582179 -18.647999 -19.032487 -18.946033 -18.573566 -18.389519 -18.275102
-20.000000 -20.000000 -20.000000 -20.000000 -20.000000 -20.000000 -20.000000

valgrinda · November 4, 2010, 14:20

Try this:
http://en.wikipedia.org/wiki/Bilinear_interpolation

cxcxcx0505 · November 7, 2010, 04:08

but,in the data that I showed, z is not a function of x and y.How should I interpolate it then?Do anyone know?
Thanks.

f-w · November 10, 2010, 17:55

I'm confused as to how each of your matrices are structured, so I can only point you to some Excel tools:
http://www.xlxtrfun.com/XlXtrFun/XlXtrFun.htm

November 1, 2010, 06:11	help for data interpolation	#1
cxcxcx0505 New Member cxcxcx0505 Join Date: May 2010 Posts: 17 Rep Power: 15	I have data like this.matrix x,y and z.They can be plot to get a 3D surface.But, the data is only 8X7 matrix.I need to interpolate so that these there matrix become 80X70.How can I do the interpolation?Do anyone know? Thanks! [matrix X] (8X7) -2.000000 -0.253290 2.530883 4.408495 6.484675 8.603029 12.000000 -2.000000 -0.198017 2.492032 4.287214 6.286022 8.542624 12.000000 -2.000000 0.055891 2.917745 4.910930 6.760385 9.110679 12.000000 -2.000000 0.440220 3.007800 5.067369 7.184489 9.370805 12.000000 -2.000000 0.649703 3.220592 5.550846 7.136382 9.419947 12.000000 -2.000000 0.766721 2.901661 5.422805 7.490025 9.714287 12.000000 -2.000000 0.400457 2.592794 5.489784 7.235743 9.964797 12.000000 -2.000000 0.396081 2.601213 5.297624 7.349845 9.914467 12.000000 [matrix Y] (8X7) 5.000000 5.000000 5.000000 5.000000 5.000000 5.000000 5.000000 0.586906 1.572462 2.538616 3.316567 2.796196 3.542882 1.551908 0.078708 0.608548 1.065732 1.461480 1.618063 1.354950 0.427768 -0.010383 -0.054167 0.823114 1.225726 1.369016 1.061109 0.239242 0.170133 0.214137 0.785628 0.945448 0.952803 0.750114 0.462212 0.232092 0.366816 0.908057 1.144984 1.088131 1.441083 0.723935 0.368313 0.745600 1.161940 1.393370 1.675171 1.795770 1.007748 5.000000 5.000000 5.000000 5.000000 5.000000 5.000000 5.000000 [matrix Z] (8X7) -9.000000 -9.000000 -9.000000 -9.000000 -9.000000 -9.000000 -9.000000 -10.935015 -11.084483 -9.977332 -9.563093 -9.508658 -9.492408 -9.727265 -11.472939 -11.769012 -11.404871 -10.792594 -10.297023 -10.676209 -10.705359 -13.393990 -13.516353 -13.449236 -13.169214 -12.843448 -13.128858 -13.073084 -15.330998 -15.373059 -15.417483 -15.363019 -14.924627 -15.198594 -15.017660 -17.271636 -17.272911 -17.276973 -16.968769 -16.716547 -17.123834 -16.837157 -18.582179 -18.647999 -19.032487 -18.946033 -18.573566 -18.389519 -18.275102 -20.000000 -20.000000 -20.000000 -20.000000 -20.000000 -20.000000 -20.000000

November 4, 2010, 14:20	Bilinear Interpolation	#2
valgrinda Super Moderator Hans Bihs Join Date: Jun 2009 Location: Trondheim, Norway Posts: 377 Rep Power: 17	Try this: http://en.wikipedia.org/wiki/Bilinear_interpolation

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November 7, 2010, 04:08		#3
cxcxcx0505 New Member cxcxcx0505 Join Date: May 2010 Posts: 17 Rep Power: 15	but,in the data that I showed, z is not a function of x and y.How should I interpolate it then?Do anyone know? Thanks.

November 10, 2010, 17:55		#4
f-w Senior Member Join Date: Apr 2009 Posts: 154 Rep Power: 17	I'm confused as to how each of your matrices are structured, so I can only point you to some Excel tools: http://www.xlxtrfun.com/XlXtrFun/XlXtrFun.htm