Returns the Chebyshev interpolation coefficients. The amplitude of the coefficients decreases exponentially and the last coefficient offers an estimate of the relative accuracy of the interpolation.
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Syntax |
Description |
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coeff=dcht(f,option); |
Returns the Chebyshev interpolation coefficients of a sampled function f. The function f must be sampled on a Chebyshev roots grid. Option: If option=1 is selected, the vector x will not include the endpoints If option=2 is selected, the vector x will include the endpoints |
Example
This example shows how to obtain interpolation coefficients from a sampled function:
Nc = 15; # Number of sample points xmin = 0; xmax = 1; x = chpts(xmin,xmax,Nc,1); # Returns Chebyshev roots grid on interval between xmin and xmax f = exp(1i*2*pi*x); # Function sampling using Chebyshev grid coeff = dcht(f,1); # Get interpolation coefficients ?abs(coeff); result: 0.304242 0.569231 0.970868 0.666917 0.302849 0.104282 0.0290919 0.00684063 0.00139224 0.000250007 4.01899e-005 5.85025e-006 7.78278e-007 9.53372e-008 1.094e-008
See Also