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Andy Pope Andy Pope is offline
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Default Excel 2003 radar chart - maximum discrete data points

Ok, so I did some more testing and I can get 3600 data points in a radar
chart. I simply plotted a1:a3600 where each cell contained the formula
=ROW().

The axis labels are a complete mess but the line is drawn.


If you willing to share, privately off NG, what you have currently and
an picture example of desired results I will have a look see.

Cheers
Andy

Daniel@UDRI wrote:
Andy,

Thanks for the quick response, but I really had hoped you would tell me that
all I had to do was blah-blah-blah and I could plot all the points I wanted!

I have a 1940's era lab instrument that uses an aging circular chart
recorder to plot the output from several transducers. I need to update it, so
now I'm capturing the digital data stream and have a VBA routine to smooth
and normalize the data, and then plot every 0.1 degrees. An X-Y chart
accurately reflects the smoothed data, but the data looks "choppy" in the
radar plot. Plotting every 1 degree of data results in a smoother looking
series but I wind up throwing away data that I'd rather not. I tried a polar
chart but because the transducers output both + and - values it looks pretty
ugly and difficult to read, and doesn't match the chart recorder output that
everyone's used to seeing (using your 2nd axis tricks I've managed to produce
a digital chart that nicely mimics the analog chart in nearly every way ---
when only 360 points are plotted).

If you're confirming the 360 limitation then I'll revisit the cartesian
solution and see what else I can come up with. Thanks.


"Andy Pope" wrote:


Hi,

Even with only 360 points the axis lines are almost a solid colour. So I
guess MS decided that 360 is probably more than enough for a radar chart.

What sort of chart are you trying to create? Not a polar chart by chance?

Cheers
Andy

Daniel@UDRI wrote:

It appears that while the radar plot can accept thousands of data points, it
is only capable of displaying a maximum of 360 discrete circumferential point
locations. If I plot a single series of 3600 data points (one point for every
1/10 degree) with constant Y values, each single plotted point on the chart
consists of ten overlaying markers. What causes this limitation, and more
importantly, is there a way to overcome it?


--

Andy Pope, Microsoft MVP - Excel
http://www.andypope.info


--

Andy Pope, Microsoft MVP - Excel
http://www.andypope.info