Shaping Data for Contour Plots

I am trying to plot a contour from data I get from a measurement. In the experiment I have two independent variables x1, x2 and the transmission signal that is T

The Data would read like this

x1=[1 1 1 2 2 2 3 3 3....]
x2=[5 6 7 5 6 7 5 6 7....]
T=[9 8 7 6 5 4 3 2 1 ....]

(I hope you get the idea!).

As I understand from the help contour(Z) requires Z=f(x,y) or in my case T=f(x1,x2) (the real data will have no analytic expression), but I don't really understand how I have to preprocess my data for contour plotting.

Hope someone can help me out here or point me in the right direction!

Best Wishes, Chris

[Christoph]

To clarify: the actual spacing in x1 and x2 is not 1, but it is the same for every set of data:

x1=[1     1     1     1     1     1     1     1     1     3......]
x2=[ 300   375   450   525   600   675   750   825   900   300 ....]
T=[ 0.4393    0.6799    0.4938    0.5233    0.6107    0.4312    0.6909    0.4153    0.6115    0.4392....]

and so on!

Answer 1

[Walter Roberson]

TriScatteredInterp()

[Christoph]

Thanks (sorry I just added a comment) I will look into that!

Response time here is... amazing!

[Walter Roberson]

... but I'm supposed to be sleeping :-(

[Christoph]

You better go before your wife or girlfriend gets angry at me for keeping you awake! ;)