functions in gauss.i -
asgauss
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asgauss(x,a) Returns an assymetrical gaussian: I0*exp(-((x-x0)/dx)^2) [+a(5) [+a(6)*x]] Where: I0=a(1) x0=a(2) dx=a(3) for x | |
SEE ALSO: | gauss, gauss_fit, asgauss_fit |
asgauss_fit
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asgauss_fit(y,x,w,guess=,nterms=) Fits an assymetrical gaussian (see asgauss) profile on a data set using lmfit (see lmfit). The set of data points Y is the only mandatory argument, X defaults to indgen(numberof(y)), weights W are optional (see lmfit). ASGAUSS_FIT tries to guess a set of initial parameters, but you can (and should in every non-trivial case) provide one using the GUESS keyword. In case you don't provide a guess, you should set NTERMS to 6 (simple assymmetrical gaussian), 7 (adjust constant baseline) or 8 (adjust linear baseline). The returned fitted parameters have the same format as GUESS, see asgauss. | |
SEE ALSO: | asgauss, gauss, gauss_fit |
gauss
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gauss(x,a) Returns a gaussian: I0*exp(-0.5*((x-x0)/dx)^2) [+a(4) [+a(5)*x]] Where: I0=a(1) x0=a(2) dx=a(3) (gaussian sigma) Works with lmfit, and can return derivates. Notes: FHWM=sigma*2*sqrt(2*alog(2)); sum(gauss)=I0*sigma*sqrt(2*pi) | |
SEE ALSO: | gauss_fit, asgauss, asgauss_fit |
gauss_fit
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gauss_fit(y,x,w,guess=,nterms=) Fits a gaussian (see gauss) profile on a data set using lmfit (see lmfit). The set of data points Y is the only mandatory argument, X defaults to indgen(numberof(y)), weights W are optional (see lmfit). GAUSS_FIT tries to guess a set of initial parameters, but you can (and should in every non-trivial case) provide one using the GUESS keyword. In case you don't provide a guess, you should set NTERMS to 3 (simple gaussian), 4 (adjust constant baseline) or 5 (adjust linear baseline). The returned fitted parameters have the same format as GUESS, see gauss. | |
SEE ALSO: | gauss, asgauss, asgauss_fit |