Have you ever tried to find a usable graph and chart class for plotting groups of data? I have. And when trying to find some cheap or free classes for plotting graph data, I found very few.
Tired of this predicament, I finally took the plunge and decided it was time to design them myself. It's a lot like trying to re-invent the wheel... because when the wheel costs $800 on the average, maybe it is time for re-inventing :)
So, here's my version of graph plotting : CGraph
Here's what it looks like during implementation :
I created a test application (testdraw) and used a menu option to show the many types of graphs created by my CGraph class and its helper classes (CGraphLegend, CGraphSeries).
A bar chart (I used bowling-type scores for the values) :
A line graph :
A pie graph, allowing multiple pies for simultaneous comparisons :
Since some people like to put graphs in a dialog, I did that too:
New in version 2 is the ability to print. Here's a print preview :
It also allows printing for line and pie graphs as well.
Version 3 additions :
Scatter Graphs :
Box-Whisker Graphs :
Stacked Bar Graphs :
XY Line Graphs :
3D Bar Graphs :
3D Stacked Bar Graphs :
3D Line Graphs (tape graph) :
3D Pie Graphs :
Version 3.0 also introduces multi-quadrant graphs. However, I have only implemented this for bar graphs (for now). Graphs can be displayed in 1 quadrant (as seen above), in 2 quadrants (either with the Y-axis splitting the middle of the X-axis, or the X-Axis splitting the middle of the Y-axis), or in 4 quadrants.
The quadrant display is still in development, so the printing of it has not yet been completed....I'll update my website with updates for it as I complete them (I didn't want to delay the other graphs too long). Some of the pages for individual graph types are also incomplete until I have time to complete the quadrant displays for those graphs.
I'm still unhappy with how the 3D Pies draw and print, so I may be updating these as time permits.
3.0.1 - July 26, 2001
- fixed problem with non-0 based tick limits.
- fixed problem with RemoveAllData() function causing GPF.
Download sample program - 694 Kb
Download CGraph class files - 535 Kb (includes help file)
HTML Help - Required to use the help files (and IE 3.0 is also required)
If using Visual Studio 6, you probably have this installed
already, though you may want this newer version.
The help and test program are continuously being modified and improved. It is my hope to add a graph wizard to the test program so users can input their values and graph type, and the graph will be generated for them, as well as a sneak-peek at the code to generate the graph.
In the sample program, I have attempted to use every command in the CGraph and other classes. To use the classes, include them in your project and at the top of the file using them. To build a simple graph, follow these guidelines :
1. Create a graph object. You can pass a parameter for graph type if desired. 2. Set your graph type, if not done in step 1. See help file for values to use for type. 3. Create a legend object. Use the SetLegend function in the CGraph to add it to the graph. 4. Create a set of series / data groups. Use the AddSeries function in the CGraph to add them to the graph. 5. Perform an Invalidate ... this will force your OnDraw function to execute. 6. In the OnDraw function, do a graph->DrawGraph(pDC); to draw the graph.
I have attempted to provide a fairly detailed help file for use with these classes. If not sufficient, mail me and let me know what I can do to improve it.
Environment: VC6, NT4 SP5, WIN 95, WIN 98