So the web server is inside an Arduino? Yes can't run GNUplot there. Why
not have the Arduino produce either Postscript or PDF? It is very easy to
draw a graph in Postscript.
That's a very good suggestion.
I think the key idea is that the programmer is making some high level
decisions that greatly simplify making the graph. Once you do that, you
don't need a complicated graphing program like gnuplot. An Arduino is smart
enough to do simple things like scaling once you have the environment setup.
Now that you remind me, I actually did that 20+ years ago. I'll fish out the
details if anybody wants to go down that rathole. The old/early Postscript
books are very good.
We were collecting loadcell data. A Mac-SE is probably about as smart as an
Arduino. Each data file had a few header lines then a bunch of numbers. To
print things, I just cat-ed a postscript program with one or more data files
and sent it to the printer. The postscript code was smart enough to read and
process the data files.
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In message 20120807180611.CF5C9800037@ip-64-139-1-69.sjc.megapath.net, Hal Mu
rray writes:
So the web server is inside an Arduino? Yes can't run GNUplot there. Why
not have the Arduino produce either Postscript or PDF? It is very easy to
draw a graph in Postscript.
Very few browsers understand postscript.
PDF requires you to keep a context of the entire document.
SVG is like postscript but browsers understand it.
Do a "show source" on this one:
http://phk.freebsd.dk/misc/hp85662_b.svg
It doesn't get any easier than that...
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