Conrol indicator window size?

 
I have a custom indicator that draws objects in the indicator window but they appear "squashed" (very short). Is there a way to control the minimum/maximum limits from within the indicator?

If I set the limits manually the indicator is correct but I need to control this from within the code.

TIA
 
I use a line index, with color CLR_NONE, and set values in it for the min and max I want the window to follow. This only works to set the min and max greater than other drawn indexes. The window limits track the highest and lowest indicator values.