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Linux Journal: A Real-Time Data Plotting Program

“This article describes the implementation of rtp (real-time
plotter), a live x,y data plotting utility based on the Qt
windowing library. rtp combines live updates with zoom in,
auto-scaling, and auto-tracking modes. It is meant to be used where
gnuplot is limited, such as the termination of a live data
pipeline.
However, rtp is small and does not attempt to cover
gnuplot’s large feature set for producing publishable data
plots….”

“rtp provides real-time updates and basic mouse-driven
resolution selection. However, it lacks gnuplot’s ability to send
formatted, titled plots to a printer. rtp is still a simple piece
of software (1200 lines of code) that needs many features added. By
describing its principles here, I hope to provide a useful, gentle
example of an application based on the Qt library and the X Window
System. I also hope to motivate some interested people to do more
work on a Linux-based real-time, interactive data visualization
system. This could be done either by extending rtp or as a
completely new project….”

“rtp’s architecture is complicated by two additional
requirements, beyond the snappy GUI response. It must quickly
update when new data points are available on STDIN. This feature is
what differentiates rtp from other plot programs, such as gnuplot.
It must also deal with the fact that rendering the data set often
takes more time than is acceptable for a GUI delay. This precludes
the use of a simple function call to render the whole plot.”

Complete
Story