XYGrapher

Introduction of XYGrapher

XYGrapher is a plotter of scatter graph (XY chart) and contour map, which is frequenlty used in science and engineering. It's a free, open-sourced software distributed under the GPL.
Data contained in text files are plotted. Having data conversion function with user-defined expression, this software would be useful particularly for ones who want to make graphs quickly without using a spreadsheet. Also, since the format of the graph configuration file (*xyg) is documented, you can automatically show figures of the output of numerical analysises or measured values retrieved from a datalogger by creating configuration files from a program and by executing this software using a Windows API such as CreateProcess function(Delphi, C++Builder, Visual C++ etc) or Shell function(Visual Basic).

Download

Download an installer for Windows
Source code
This software is written in FreePascal with an integrated development environment named Lazarus. You can freely download, modify, compile, and use it under following license (GPL ver.2).

Basic features required for a XY plotter are supported:

Nonlinear curve fitting with user defined function as well as regression analysis for linearizable functions such as linear, exponential, or logarithmic function.
Drawing user defined functions, which are highly readable with parameters and brackets([ ], { })
Cubic spline that interpolate data points smoothly can be applied
Numbering of the horizontal axis can bedate format
Error bar and data labels that automatically locate themselves

Quick Processing

Wizard-guided quick configuration by drug-dropping a datafile into the desktop icon.
Auto-scaling of axises including decision whether linear or logarithmic scale
Pasting data copied from spreadsheet is supported.

Presentation and Publishing Quality

In the title and legend, you can set font name, size, color, bold, italic, superscript, subscript for each letter.
Rich decolations such as arrow, 3-D effected marker, or shadowed legend frames.
In slide-show mode, you can display slides in full-screen one by one guided by slide program that you configure
In exporting as a image to presentation software, black objects such as labels, frames, and curves are automatically turned into white, which style fit to dark slide, when navy background is selected.

Other key features:

Data trimming which excludes errornous data.
Auto refreshing that automatically sences the update of a datafile and reload it.
Mathematical mode suitable for teaching and learning mathematics.
Numerical integration of user-defined function or plotted data

[Advantages over XY-plotting of spreadseet]

[Advantages over chart component of programming languages]