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NLREG -- Nonlinear Regression and Curve Fitting
NLREG是一款強大地統計分析軟體。能夠進行線性和非線性回歸分析、表面和曲線擬和。此款軟體可以為一個方程式決定其參數值。NLREG能夠處理線性、多項式、指數、對數、周期性與一般的非線性函數。
NLREG features a full programming language with a syntax similar to C for specifying the function that is to be fitted to the data. This allows you to compute intermediate work variables, use conditionals, and even iterate in loops. With NLREG it is easy to construct piecewise functions that change form over different domains. Since the NLREG language includes arrays, you can even use tabular look-up methods to define the function.
The Standard version of NLREG can fit up to 5 variables and parameters to the data observations. The Advanced version can handle up to 2000 variables and parameters. In addition, the Advanced version can generate 3D surface plots such as shown here:
In addition to performing classic nonlinear regression, NLREG can be used to find the root or minimum value of a general multivariate, nonlinear function. It can also be used in a special form where the independent variable is omitted; an interesting application of this is "circular regression" where a circle is fitted to a set of data points.
產品特色
In addition to fitting a function to a set of data values, NLREG can generate various plots showing the fit or providing information about the quality of the fit.
Function Plot
A function plot displays the actual data values as X-marks and shows how the fitted function aligns with the data points. Optionally, the plot can show vertical lines between the data points and the function curve representing the residual (error) values for each point. It is also possible to specify a domain over which the function will be plotted allowing it to be extrapolated in either direction beyond the domain of the data values.
3D Surface Plot
The Advanced version of NLREG supports 3D surface plots. Surface plots depict the value of the dependent variable on the Z axis and two independent variables on the X and Y axes. Circles are used to show the actual data points. Optionally, contour lines can be shown on the base surface below the figure.
Surface Contour Plot
The Advanced version of NLREG supports surface contour plots. Contour plots depict the value of the dependent variable as color-coded regions and the values of two independent variables on the X and Y axes.
Surface Residual Plot
The Advanced version of NLREG can generate 3D surface residual plots showing the computed and actual value of each data point for functions with two independent variables. The computed and actual points are shown as circles with a line connecting them. Optionally, a contour plot of the function values can be shown on the surface of the plot.
Function Residual Plot
This type of plot shows the residual (error) values. That is, each Y value corresponds to the difference between the actual value of a data point and the computed value of the fitted function at the corresponding X value. It is useful for identifying data points that deviate significantly from the fitted function.
Normal Probability Plot
The actual value of each residual is plotted on the vertical (Y) axis and the expected value of the residual, assuming the residuals are normally distributed, is plotted on the horizontal (X) axis. If the residuals are normally distributed, the resulting plot will be a straight line passing through the origin with a slope of 1. A normal probability plot is useful for determining whether the residuals are normally distributed. If they are not normally distributed then the form of the function being fitted may be inappropriate for the data.
Controlling Plot Colors
NLREG allows you to specify the colors of various items in a plot. Three sets of color values are stored: (1) colors for plots displayed on your screen, (2) colors for plots that you print, and (3) colors for plots saved to disk files.
Saving Plots to Disk Files
NLREG makes it easy to save plot images to disk files so that you can import them into documents. Once you get a plot that you want to save, just click the "Save-plot" button and specify the name of the file, the size of the plot and whether you want it saved as a JPG image or a BMP image.
系統需求
- Windows 95/2000/XP/Vista/Windows 7/Windows 8 (There is no version of NLREG for Linux or Macintosh)
- At least 64 MB of memory (256 MB recommended).
- 5 MB of disk space.
NLREG版本比較
|
|
Standard GUI
|
Advanced GUI
|
DLL Library
|
COM Object
|
|
Maximum variables
|
5
|
2000
|
2000
|
2000
|
|
Maximum parameters
|
5
|
2000
|
2000
|
2000
|
|
Maximum data records
|
500
|
unlimited (1)
|
unlimited (1)
|
unlimited (1)
|
| C-like language | Yes | Yes | Yes | Yes |
|
Line function plots
|
Yes
|
Yes
|
No
|
No
|
|
Line residual plots
|
Yes
|
Yes
|
No
|
No
|
|
Normal probability plots
|
Yes
|
Yes
|
No
|
No
|
|
3d surface plots
|
No
|
Yes
|
No
|
No
|
|
3D residual plots
|
No
|
Yes
|
No
|
No
|
|
Surface contour plots
|
No
|
Yes
|
No
|
No
|
|
Call from C++
|
No
|
No
|
Yes
|
Possible (5)
|
|
Call from Visual Basic
|
No
|
No
|
Possible (6)
|
Yes
|
|
Call from ASP
|
No
|
No
|
No
|
Yes
|
Notes:
(1) The maximum number of data records that can be processed depends on the available memory space on your computer.
(2) The NLREG program file, manual in PDF format, and example files will be delivered via download.
(3) The NLREG program is sent on a CD with a bound, printed manual. USPS Priority Mail is used.
(4) The NLREG program is sent on a CD with a bound, printed manual. Postal air mail shipping is used.
(5) The COM object version can be called from C++, but you are responsible for passing and receiving Variant data types.
(6) The DLL library can be called from Visual Basic, but it is much more convenient to use the COM object version.
(*) There is a $20 service charge for orders using a purchase order that require an invoice for payment.
試用版限制
- Maximum of 5 input variables.
- Maximum of 5 parameters whose values will be calculated.
- Maximum of 50 data records (observations).
- It will only run for 30 days.