plot2d failed to plot too many discrete points



On 5/13/2012 7:43 AM, XeCycle wrote:
> Richard Fateman<fateman at eecs.berkeley.edu>  writes:
>
> [...]
>
>> I have  fairly nice computer display, and it has about 1.6
>> million discrete pixels.
>> Plotting 2 million discrete non-overlapping points on it would
>> not be possible.
>> Perhaps you would find difficulties regardless of the plotting program.
>> RJF
> You're missing the point.  This many numbers are needed for my
> computation, and will be further processed; now I want to have an
> impression on how it looks like, so I tried to plot it.
Let us say that you have a display which is 1200X1000 pixels.
Allocate a bit array of that size. Clear it to zeros.
Run through your discrete points and each time you get close enough (scaled)
to one of those points, turn it to a one.
send the bit array to some display program.

Probably would take you 1/1000 of the time.

Oh, and if you were doing this in a numerical system, you should
probably do the same thing.



>    Now that
> it cannot plot something like this, I'll have to write something
> to decide which points to plot, that's an overkill.
Your original conception of what should be done can be re-visited.

>
> Such a process is what I need, but didn't find it in the docs.
> So asking here, not provided yet?
>
>
>
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