Exponential least-squares curve fit function.

Syntax

c,s,f = ExpCurveFit(Ind, Dep)

Arguments

Name

Description

Ind

A vector of independent data.

Dep

A vector of dependent data.  All entries must be positive.

Outputs

Name

Description

c

A vector of the two coefficients.

s

A vector of the statistical fit quality.  See Comments below.

f

A vector of an exponential least squares fit.

Example

For a given set of independent and dependent data find the best exponential fit.

Syntax

c,s,f = ExpCurveFit([1,2,3,4],[1,4,9,16])

Result

c = 0.5    0.91

s = 3.28   0.95

f = 1.25   3.10    7.73     19.27

Comments

The result is the exponential function, y = aebx, which best fits the original curve as determined by least squares criteria.

The output c includes the two coefficients (a,b).

The output s includes mean squared error and the correlation coefficient (the square root of the coefficient of determination R2 ) respectively.

Ind and Dep must have the same number of elements.

See Also:

MultiRegress

PolyCurveFit

NLCurveFit