FindGraph
FindGraph is comprehensive graphing, curve fitting, and digitizing tool. FindGraph offers 12 generic fits, including linear regression, logistic functions, fourier approximation, neural networks, B-splines and parametric curves least squares approximations, plus a library of over 300... Built-in Wizard helps to apply different curve fits to discover the model that best describes the data. ... The program supports OLE automation and can be built-in to other software applications. ... Built-in Wizard helps to digitize the data.
http://www.uniphiz.com/findgraph/fgraph.exe - 3Mb - Download - Screenshot

NLREG
NLREG performs nonlinear regression and curve fitting. NLREG fits a mathematical function whose form you specify to a set of data values. Virtually any type of function can be fitted. NLREG includes a programming language similar to C that you use for describing the function to be fitted. ... The programming language includes a large selection of built-in library functions (sin, cos, log, exp, etc. ... ) that makes it easy to describe complicated models. ... Two dimensional line and three dimensional surface plots can be generated.
ftp://ftp.nlreg.com/nlrsetup.exe - 1Mb - Download - Screenshot

DataFit
DataFit is a tool used to perform nonlinear regression (curve fitting), statistical analysis and data plotting. What sets DataFit apart from similar curve fitting and regression programs is its ease of use. DataFit is driven by a well-designed graphical interface, so there are no complicated... Macro capability allows curve fitting operations to be performed non-graphically, either in batch mode or by calling DataFit from an external program. ... Plots can be saved as templates, which allows them to be applied to new plots in order to instantly give them your own custom appearance.
http://www246.pair.com/oakdale/datafit.zip - 6Mb - Download - Screenshot

DMFitter ActiveX control
DMFitter ActiveX control allows you to add sophisticated regression analysis tools to your software in a few lines of code. Features include: both linear and nonlinear (Levenberg-Marquardt) least squares curve fitting algorithms, arbitrary user models (defined analytically or by string... Examples for Excel, VB, Delphi, MSIE, Data Master 2003 and scripting languages are included.
http://www.datamaster2003.com/downloads/fitter.zip - 198Kb - Download - Screenshot

Graphit
Low cost 2D function plotting software. Use up to 8 functions with cascades. Displays 2 simultaneous plots with cursors positions and deltas. File load, save, and print. Input point overlays for curve fitting. Trig, Ln, Log functions supported.
http://www.gecces.com/pub/GraphitInstaller.exe - 358Kb - Download - Screenshot

EasyFit
EasyFit is a distribution fitting software designed to facilitate probability data analysis and best model selection. It allows to easily and quickly select the probability distribution which best fits to your data. BENEFITS of EasyFit: saves you time and makes your work more efficient; helps... FEATURES of EasyFit: supports over 30 probability distributions; includes a powerful distribution fitting algorithm and a manual fitting capability for advanced users; supports goodness of fit tests and high-quality graphs; provides an Excel-like spreadsheet for data input and manipulation.
http://www.mathwave.com/downloads/easyfit-setup.exe - 2Mb - Download - Screenshot

ImageDIG
ImageDIG consists of three integrated modules which allow the user to convert 2D flat images into 3D (x,y,z) data or if a graph, convert the graph in image form into 2 dimensional numerical data. The third module is a full analysis plotting utility where the user can import either the 2D or 3D... Graph processing functions include statistical analysis such as: Min/Max/Mean Fitting - Standard deviation, best fit, and curve fit. ... Curve fit includes: variable-order polynomial, logarithmic, exponential, power, inverse, spline, and moving averages Additional features include a built in...
http://www.imagedig.com/download/install.exe - 5b - Download - Screenshot

Graphmatica
a powerful, easy-to-use, equation plotter with numerical and calculus features: - Graph Cartesian functions, relations, and inequalities, plus polar, parametric, and ordinary differential equations. - Up to 999 graphs on screen at once. - New data plotting and curve-fitting features. ... - On-line help and demo files make getting up to speed a snap. ... In summary, a great tool for students and teachers of anything from high-school algebra through college calculus. ... - Print your graphs or copy to clipboard as bitmap or enhanced metafile in black-and-white or color.
http://www.graphmatica.com/distrib/grmat20n.zip - 322Kb - Download - Screenshot

Advanced Grapher
Powerful but easy-to-use graphing, curve fitting and calculating software. Graphs Cartesian (Y(x) and X(y)), polar and parametric functions, graphs of tables, equations (implicit functions), inequalities and slope fields. Up to 100 graphs in one window. ... The program has printing capabilities, multi-document interface, customizable toolbars. ... Supports English, Dutch, French, German, Italian, Portuguese, Russian and Spanish interfaces. ... You will be able to create high-quality graphs and copy them to your documents (as EMF or BMP).
http://www.alentum.net/files/agrapher.zip - 1Mb - Download - Screenshot

Arkan
Arkan is designed to convert border of a raster mask (selection of an object in scene) or any closed polyline into B-spline (piecewise cubic Bezier curve) representation spread widely in vector graphics packages. Arkan chooses the best position both for node points (junctions of adjacent Bezier... * Features & Benefits Perfect quality of fitted B-splines, even if you limit the number of Bezier curve pieces. ... However operating in this mode consumes significantly more processor power. ... The number of nodes, their positions and positions of controls nodes, everything is detected...
http://patchmaker.net/free/Arkan.exe - 1Mb - Download - Screenshot