Free plots software for windows

Z-Plot is a free software that allows you to visualize a multitude of mathematical functions and curves.
The software has a powerful mathematical formula interpreter, that also allows the user to handle complex numbers easily.
The display can be switched from 2D to 3D mode. Additionally, diagrams can be made from data tables.
Main features:
- 3D/2D display that be rotated and scaled freely
- The common mathematical functions are supported
- Calculating with complex numbers is supported by any mathematical operation. Additionally, it is possible to determine the real part, imaginary part, argument and absolute value of complex expressions.
- Chose between linear and logarithmic axes scaling.
- Integrated calculator including numerical integral and differential calculus
- Make diagrams from a spreadsheet
- With detailed online help.

RtPlot is a small program for displaying 2D plots in real time. It consumes little resources. It was written because of the need to monitor the progress of computationally intensive scientific programs which run for a long time and occasionally produce output suitable for plotting.
The user can open as many windows as needed for plotting. Each window can monitor several data files and plot their contents.
When a data file is updated by another concurrently running program, its plot is automatically updated as well. It is also possible to view in a window several recent updates to a data file.
The user can configure the frequency in which RtPlot checks for file updates, stop or renew the updating of plots, the range of x & y columns, number of ticks along axes and other parameters.
Configurations can be made with the mouse, command line or XML configuration files.
Each plot can be printed or saved in BMP/PNG formats, either manually or when the display is updated.

FuncPlotter is a combined Java application and applet for displaying two-dimensional plots of explicit functions in one variable.
For example FuncPlotter can display functions of the form y = f(x), where f(x) is an arbitrary function composed from a set of common mathematical operators.
Main features:
- It can be used either as a Java application or as a Java applet that is included in a page of HTML or XHTML.
- Up to 20 functions can be plotted simultaneously. The colour of each plot can be specified.
- When used as an application, FuncPlotter can save a set of up to 20 functions to a file and can load files saved in this way. The files are saved either as XML or in a simple text format, allowing you to create and edit files with a text editor. (The ability to load and save files is not available in applet mode.)
- In application mode, up to 9 documents (sets of functions) can be open at once, each in its own window. You can switch quickly and easily between documents. However, the document windows are of fixed size and are overlayed: you cannot tile or cascade the windows. (Multiple windows are not available in applet mode, which uses only a single window.)
- When the mouse cursor is over the plot area, the x and y coordinates at the cursor are displayed.
- Plots can be scrolled by clicking on buttons, rotating the mouse wheel, dragging the mouse or pressing keys.
- Plots can be zoomed in and out. Each of the x and y dimensions has its own independently selectable zoom factor.
- Plots can be exported as an image file in PNG format