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- ** File: TPSht_01.hlp
- ** Index: 40
-
- ** More Sheet View Help
- :: Interpolation commands
- :: Fitting commands
-
-
- █ Interpolation
-
- The Math | Interpolate menu item
- contains a pop-up menu which contains the
- data interpolation commands.
-
- █ Polynomial
-
- This command interpolates the selected
- X-Y columns by a polynomial of degree
- n-1, where n is the number of valid data
- points of X-Y columns.
-
- █ Rational
-
- This command interpolates the selected
- X-Y columns by a rational function of
- degree K-1, where K is the number of
- valid data points of X-Y columns.
-
- █ Natural Spline
-
- This command interpolates data using
- a natural cubic polynomials between each
- successive pair of nodes.
-
- █ Clamped Spline
-
- This command interpolates the selected
- X-Y columns by a clamped cubic spline.
- The boundary conditions are given in a
- way such that the third derivatives are
- continuous.
-
- █ Stineman
-
- This command interpolates the selected
- X-Y columns by a Stineman function.
- The Stineman function consists of
- piecewise diagonal rational functions
- of order 3 (i.e. the degree of
- numerator polynomial is 2 and the
- degree of denominator polynomial is 1).
- These rational functions are to have
- continuity up to first derivative.
-
-
- █ Fitting
-
- This menu item contains six fitting
- commands. The first five commands are
- linear in terms of the parameters
- appearing in the pre-defined function form.
- The last command is for user-defined
- non-linear parameter fitting.
-
- █ Line: a*x+b
-
- This command fits the selected x-y
- data by a straight line.
-
- █ Power: a*x^b
-
- This command fits the selected x-y
- data by a power function.
-
- █ Exp: a*exp(b*x)
-
- This command fits the selected x-y
- data by a mono-exponential function.
-
- █ Polynomial
-
- This command fits the selected x-y
- data by a polynomial
-
- █ Spline
-
- This command fits the selected x-y
- data by a natural cubic spline.
-
- █ User Defined
-
- This command performs non-linear
- curve fitting. It displays the Fitting
- dialog box. In this dialog box, you can
- type in a model or load/save a model
- from/to disk. The model file format
- are described in Section 6.4.2. In the
- model equations, you can have up to 10
- independent variables, 10 dependent
- variables, and 10 parameters. This means
- you can do 3D curve fitting easily with
- the Math | Fitting - User-Define command.
-
- See TpSht_09.hlp (Index: 48) on TechPlot's
- model equation convention.
-