Re: plotting from within Fortran?

On 2008-01-07 11:59:52 -0400, Louis Krupp <lkrupp@xxxxxxxxxxxxxxxxxxxxxxx> said:

Bart Vandewoestyne wrote:
On 2008-01-07, highegg <highegg@xxxxxxxxx> wrote:
I'd like to point out that "real-time" makes not much sense here - a
typical adaptive integrator will be slowed down by an order of
magnitude by plotting something during the process, and yet still the
process may (and will, probably) be too fast to watch, so it will have
to be slown down.

You are right. I am however not sure about what exactly my student
wants to plot. We will have a meeting this week and
we'll discuss about that. The splitting of the regions is what I
expect it to be... but maybe he also wants to plot other things
and maybe he wants those things to be visualized in real-time. I
agree that if real-time is not necessary, then it is probably
better to split it up into writing out certain data-files and
then post-processing them using his favorite plotting tools.

Are there other advantages of your suggested approach over simply
generating plot files to be plotted off-line by e.g. gnuplot, and then
possibly combined to a movie?

For the moment i completely agree with you on the off-line
plotting. I'll discuss it with my student and see if he really
needs on-line visualization.
<snip>

Please note that the terms "real time" and "on line" are sometimes confused. Strictly speaking, a real time system is tuned to respond to "real world" inputs as they occur; see:

http://en.wikipedia.org/wiki/Real_time

or (for a broader definition):

http://www.webopedia.com/TERM/R/real_time.html

"On-line" has a fuzzier, more historical definition. Once upon a time, an on-line plot meant that the program connected to the plotter, did its thing, and released the plotter; for an "off-line" plot, the program wrote a tape which was then carried to the plotter, where an operator queued it behind other plot tapes and then mounted it on the plotter's tape drive to be printed when its turn came.

In your case, I think you'll see the results quickly whether the Fortran program calls a plot package or creates files to be plotted after the program has finished. The decision will probably come down to ease of programming.

Louis

Sometimes there is a distinction between on-line and off-line in which on-line
means to process each input before proceeding on to the next input. In off-line
all the inputs are collected before any processing. The issue is that some of
processing of some inputs may help in the processing of other inputs. The
off-line process then has the option of the order of processing.

The distinction may arise in the processing of database queries for example.

Integration of panels leading to the whole could be used to construct
another example.




.

Relevant Pages

  • Re: plotting from within Fortran?
    ... but maybe he also wants to plot other things ... then post-processing them using his favorite plotting tools. ... Once upon a time, an on-line plot meant that the program connected to the plotter, did its thing, and released the plotter; for an "off-line" plot, the program wrote a tape which was then carried to the plotter, where an operator queued it behind other plot tapes and then mounted it on the plotter's tape drive to be printed when its turn came. ...
    (comp.lang.fortran)
  • Re: Plot f(x)=x+A where A is a list of values?
    ... I've never seen this occur in algebraic plotting; ... If you plot a set of non-algebraic programs (even if disguised ... will of course be connected by the plotter. ... then one should get consistent results, regardless of plotting sequence. ...
    (comp.sys.hp48)
  • Re: writing at the end of the lines
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    (comp.lang.fortran)
  • Re: "USE MATLAB" writing at the end of the lines
    ... If there is a plotting program which is sane enough to ... >>>other efficient way to accomplish this (ie appending an extra column ... > cannot plot across rows. ... > evolution of fvs x over time without any external processing. ...
    (comp.lang.fortran)
  • Re: Need urgent help
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