One direction autoscale chart

[guangdew1]

I intend to show only the positive part of the chart. Because of noice, it will show some negative scales if I use autoscale x. I don't know whether we have a way to set the chart start from zero and autoscale x. Anyone can give some suggestions? Thanks in advance.

Guangde Wang

[falkpl]

You can prefilter the data going into the chart, put a minimum threshhold and replace the sub-th value with the minimum or 'nan' either way this should fool the rescale option.  You can also turn off the autoscale and set the maximum y value to 1.2 x max value of your data and fix the minimum value.

Paul

[guangdew1]

Paul, thank you for your response. I'll filter the data.

Guangde

[falkpl]

One cool and little know trick is replace using a NAN, this will leave the plots discontinious that is it makes the filtered points not visible.  Replacing the negative values with zero gives the impression that the values were zero as opposed to invalid values.

Paul 

[mikeporter]

...and learning to do that without using a loop (yes it is possible - in at least a couple ways) might be an interesting exercise in polymorphism and how NaNs are handled.

Mike...