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Double Interpolation from a table

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I'm trying to interpolate off the table attached.
E = xlsread('Exhaust_Cp.xlsx')
m_dot_exhaust =[0.0168758667758187 0.0168286355030812 0.0168280643029830 0.0163466175171450]
T_avg_rankine =[871.065000000000 974.025000000000 1115.12700000000 1304.31600000000]
[x,y]=meshgrid(E(2:end,1),E(1,2:end))
z=[E(2:end,2:end)]
Vq=interp2(x,y,z,m_dot_exhaust(1),T_avg_rankine(1))
But I keep getting this error. Can anyone tell me how to resolve this?
Error using griddedInterpolant
The sample points arrays must have the same size as the sample values array.

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Karthik Agnihotri
Karthik Agnihotri on 22 Oct 2020
I'm getting NaN when I try that.
I've attached my file here @KSSV
KSSV
KSSV on 22 Oct 2020
It is beacuse, your points are lying outside the given grid....it comes to extrapolation and the result cannot be trusted.
Karthik Agnihotri
Karthik Agnihotri on 22 Oct 2020
Ok..how would you propose I go about interpolating any data from this table if I know the temperature and mass flow? Given that I have a new data set for mass flow rate. Please let me know if you have any suggestions. Thanks

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Accepted Answer

KSSV
KSSV on 22 Oct 2020
Vq=interp2(x,y,z',m_dot_exhaust(1),T_avg_rankine(1)) ;

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KSSV
KSSV on 22 Oct 2020
m_dot_exhaust =[0.0168758667758187 0.0168286355030812 0.0168280643029830 0.0163466175171450];
T_avg_rankine =[871.065000000000 974.025000000000 1115.12700000000 1304.31600000000];
[x,y]=meshgrid(E(2:end,1),E(1,2:end));
z=[E(2:end,2:end)];
Vq=interp2(X,Y,z',T_avg_rankine,m_dot_exhaust*1000)
From your given points T_avg_rankine is x-axis and m_dot_exhaust is y-axis. Check your units......if I multiply this by 1000, the points very much lie in the grid.
Karthik Agnihotri
Karthik Agnihotri on 22 Oct 2020
Thanks for the help! I'll look into the data collected again

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