Problem in plotting graph

[Hnagpal]

Hi,

I am trying to plot a graph. I want to refrence my initial position so that if there is change in values it will be elongation. So I want my graph to start plotting after initial refrence position is marked. Right now what is happening is it take iniatial reading as zero and distance between two sensors is like 7.5meters so it draws a line at 7.5 meter and then come to elongation after initial reference is clicked. Since change is going to be 10-20 mm it does not show the curve. So what can i do to make graph start after i click initial reference position and ignore previous values.

Thank You

[TheGeeze]

It sounds like you just need to remove an initial offset from your graph.  To do this, pull the first value from the array you are graphing, and subtract that from all your other data points. Let us know if this is not a satisfactory solution.

Ryan

[JÞB]

It seams the trouble you are having is that te initial value for Distance in mm is 0.  Set it to NaN.  Nan's Don't plot. 

[Hnagpal]

Thanks Ryan and Jeff, It worked