CLsqFit:SetBasisFunc

The SetBasisFunc method selects the basis function to use for the fit. This function selects one of the two built-in basis functions or a function you specify in the script. This topic and the details of parameter passing are discussed in Basis Functions.

Syntax

CLsqFit:SetBasisFunc( selection )

where

selection is a number or string specifying the basis function. To use a built-in basis function, pass its number. To specify a basis function declared in the script, pass its name as a string.

This function takes either a number of string value to select the basis function. Mira interprets a number value as a built-in basis function. A string is interpreted as the name of a function in the script:

1	The built-in (default) n-dimensional polynomial basis function.
2	The built-in hyperplane basis function.
(else)	The name of a basis function defined in the script.

Note that the value returned by GetBasisFunc is always a string. The number index 1 or 2 is returned as a string as is the name of a basis function declared in the script.

Examples

The following script selects the built-in hyperplane basis function.

L = CLsqFit:new()	-- create a CLsqFit object
	-- no function declared, n-dimensional polynomial (1) assumed
L:SetBasisFunc( 2 )	-- select built-in function 2, the Hyperplane
sName = L:GetBasisFunc()
Printf( "Func= '%s'\n", sName )	-- result: Func= '2'

To next example declares a basis function in the script and then registers it for use. This function, named "Line", fits a line:

function Line( n, c )	-- declare the basis function
b = {}	-- declare an array for the basis vector
b[1] = 1	-- basis vector element [1] is 1
b[2] = c[1]	-- basis vector element [2] is c[1]
return b	-- return the basis vector
end	-- end of the basis function
L = CLsqFit:new()	-- create a CLsqFit object
L:SetBasisFunc( "Line" )	-- register the script function "Line"
sName = L:GetBasisFunc()
Printf( "Func= '%s'\n", sName )	-- result: Func= 'Line'