Decimation "hides" data (showallpoints)

Mark · Post by **Mark** » Wed Jun 16, 2004 2:18 pm

Hi,

I'm plotting vectors that are around 10,000 points in length. I set ShowAllPoints to false to speed up the plotted (there are only so many pixels on the screen).

I was wondering if it would be possible to change the decimation algorithm so that when it picked 1 point out of 10 possible points to plot, it would pick the highest point.

My data has spikes in it and the spikes don't always show up because (I assume) they are being decimated out.

Thoughts? Ideas? Advice?

Thanks!

Marjan · Post by **Marjan** » Sun Jun 20, 2004 2:50 pm

Hi.

I was wondering if it would be possible to change the decimation algorithm so that when it picked 1 point out of 10 possible points to plot, it would pick the highest point.

Yes, by changing the code in fastline series. But instead of using only max value, I'd make it more general and allow the user to select between several different options: replace group with min, max, average, min and max value. All this can also be done outside TeeChart (downsample values by using external routine) and then using fastline series only for displaying decimated data. I've logged this to the wish list and with any luck we'll implement it for next major release.