[General Information]

Function Name=Log3P1		; name show up in the select function dialog
Brief Description=Three-parameter logarithm function
Function Type=Built-in		; source type, built-in, user-defined, external dll
Function Form=Expression	; function form;
Function Source=fgroup.Log3P1
Number Of Parameters=3
Number Of Independent Variables=1
Number Of Dependent Variables=1


[Fitting Parameters]

Naming Method=user-defined
Names=a,b,c
Lower bounds=--,--,--
Upper bounds=--,--,--
Meanings=coefficient,coefficient,coefficient

[Independent Variables]

x = 


[Dependent Variables]

y = 


[Constants]


[Formula]

y = a - b*ln(x+c)

[Constraints]


[Parameters Initialization]
sort( x_y_curve );
smooth( x_y_curve ); 
c = min( x_data ) - 0.5 * abs( min( x_data ) );
Dataset xx;
x_y_curve.AttachX(xx);
xx = ln( xx + c );
double coeff[2];
fitpoly( x_y_curve, 1, coeff );
a = coeff[0];
b = -coeff[1];


[Initializations]


[After fitting]


[Controls]
General Linear Constraints=Off
Initialization scripts=Off
Scripts After fitting=Off

