You can do some rough signal conditioning. Divide your data into small
chunks, enough to fill a fraction of the 32k maximum, and plot three points
from each chunk: min, max, and mean. Pick the number of points per data
chunk for what fits the data best. This approach will show any peaks,
assuming you don't have two within a chunk, without bogging down Excel.
- Jon
-------
Jon Peltier, Microsoft Excel MVP
Tutorials and Custom Solutions
Peltier Technical Services, Inc. -
http://PeltierTech.com
_______
wrote in message
...
Thanks, I'll try ScreenUpdating.
I've been scrolling the page so the chart's are out of view, which
helps tremendously, but it's still slow. It will plot all 4e6 points
however
Just so you don't think I'm a bit foolish in the data size, I'm trying
to plot a timebased dataset with 1e6 points on 4 channels. I've
strung together 32 maximum sized series for each of the 4 series.
(People still want to pick up every spike on a general graph.).
I'll probably revert to what I started with, a single condensed graph,
with an additional detailed plot with pan and zoom buttons.
jeff
On Apr 19, 6:42 am, "Jon Peltier"
wrote:
The maximum points allowed in a chart is 0.25e6 points. Even this many
are
too many in 99% of the cases I've seen; that's almost the number of
pixels
in a full page chart.
You could try setting Application.ScreenUpdating to False at the start of
your procedure and True at the end, which doesn't always affect charts
the
way you'd expect. Also build the chart on a sheet that is not the active
sheet, to reduce Excel's compulsion to update the display. I'm not sure
setting Application.Calculation to manual would help in this case.
If you're using 2007, charts with lots of points are a disaster anyway,
and
charts redraw themselves at the slightest provocation. 2003 and earlier
behave much more nicely.
- Jon
-------
Jon Peltier, Microsoft Excel MVP
Tutorials and Custom Solutions
Peltier Technical Services, Inc. -http://PeltierTech.com
_______
"schuhjm" wrote in message
...
Hello,
I'm working with a large amount of data I'd like to plot in an xy
scatterchart (1e6 to 4e6 datapoints).
I'm building the chart in VB by creating multiple series of the maximum
32k
size.
Is there a way to build the all the series without having the chart
refresh
until done? In the worst case, I have 128 series to plot.
In otherwords, I'd like to refresh the chart on demand, and only when
desired.
Thanks,
Jeff