How to interpolate a set of data wher the X size is different for the Y size

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Hello,
I have a set of data X (size=2001,1) and Y (size=3,1). The Z matrix size is (2001,3). X and Y have uniform increments by the X size is not the same as the size of Y.
Can I use meshgrid or interp2? I tried but I got errors
for meshgrid
Error using griddata
The lengths of X and Y must match the size of Z.
for interp2
Error using griddedInterpolant
Sample points vector corresponding to grid dimension 1 must contain 3 elements.
Error in interp2>makegriddedinterp (line 226)
F = griddedInterpolant(varargin{:});
Error in interp2 (line 126)
F = makegriddedinterp({X, Y}, V, method,extrap);
Error in read_mydata (line 41)
Vq = interp2(theta,phi,co_amp_db,10,22);
Error in read_mydata (line 40)
vq = griddata(theta,phi,co_amp_db,10,22)
=======================================
Here is my code
xlx=input_data_file;
sheetname='MAIN';
addpath(pathToOptimizer)
nrow=2002;
ncol=13;
rangero=[1,1,nrow,ncol];
sheetname='Test';
[NUM,TXT,RAW]=readmycells(xlx,rangero,sheetname);
phi=NUM(1,3:4:ncol)';
theta=NUM(2:nrow,1);
nnp=size(phi);
nnt=size(theta);
np=nnp(2);
nt=nnt(1);
co_amp_db=NUM(2:nrow,2:4:ncol);
co_phase_db=NUM(2:nrow,3:4:ncol);
cx_amp_db=NUM(2:nrow,4:4:ncol);
cx_phase_db=NUM(2:nrow,5:4:ncol);
vq = griddata(theta,phi,co_amp_db,10,22);
Vq = interp2(theta,phi,co_amp_db,10,22);

Respuesta aceptada

dpb
dpb el 21 de En. de 2023
x=1:10;y=1:3; % coarse spacing
z=rand(numel(x),numel(y));
surf(y,x.',z)
hold on
Z=interp2(y,x.',z,1:0.5:3,[1:0.5:10].'); % increase spacing by half...
surf(1:0.5:3,[1:0.5:10].',Z); % plot on top...
  4 comentarios
VBBV
VBBV el 22 de En. de 2023
Movida: VBBV el 22 de En. de 2023
Check also scatteredInterpolant or griddedInterpolant

Iniciar sesión para comentar.

Más respuestas (1)

Jonas
Jonas el 21 de En. de 2023
you can usw meshgrid to prepare your xq and yq:
Y=9:13;X=1:2:5;Z=rand(5,3);
[xq,yq]=meshgrid(1:0.5:5,9:0.5:13);
interp2(X,Y,Z,xq,yq)

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