Linear Equations

Linear equations are defined as equations that are linear in the parameters. For example, the polynomial library equations are linear. The Linear Equations pane is briefly described below.

• Independent variable -- Symbol representing the independent (predictor) variable. The default symbol is x.
• Equation -- Symbol representing the dependent (response) variable followed by the linear equation. The default symbol is y.
• Unknown Coefficients -- The unknown coefficients to be determined by the fit. The default symbols are a, b, c, and so on.
• Terms -- Functions that depend only on the independent variable and constants. Note that if you attempt to define a term that contains a coefficient to be fitted, an error is returned.
• Unknown constant coefficient -- If checked, a constant term is included in the equations to be fit. Otherwise, a constant term is not included.
• Add a term -- Add a term to the equation. An unknown coefficient is automatically added for each new term.
• Remove last term -- Remove the last term added to the equation.
• Equation -- The custom equation.
• Equation name -- The name of the equation. By default, the name is automatically updated to be identical to the custom equation given by Equation. If you override the default, the name is no longer automatically updated.

To save custom equations for later use, you should save the curve fitting session.