I need someone, anyone, to explain in plain English how to display 
logarithmic data in object graphics.  I have stared at the 
obj_logaxis.pro code in the examples directory and I still can't figure 
out why their stuff works and mine doesn't.  I can't stand how RSI 
didn't put any explanation into their documentation, but just included 
the example code  (poorly indented code at that -- at least in the 
manual itself).

In my last failed attempt, the Y axis and the data are smushed against 
the bottom of the plot.  In previous attempts, I managed to get the 
correct log curve in the plot, except the axis was scaled incorrectly 
and I had a few experiences with the infamous "infinite plot range" and 
stuff like that.  But no matter what properties I get and set, I can 
never seem to make things work.  I already have code which works great 
for linear axes.  I just want to add a Y axis log capability to this 
code -- that's all, nothing more.

If this goes on for much longer, this might take the "frustration time" 
record away from when I first learned about 8-bit and 24-bit colors in 
direct graphics.  ;-)

-Mike

Well, it seems that I have figured out my immediate problem.  I finally 
have a log plot working!  Turns out that the real problem was what I was 
giving to YCOORD_CONV.  *sigh*

-mike

Michael Wallace wrote:
> Well, it seems that I have figured out my immediate problem.  I finally 
> have a log plot working!  Turns out that the real problem was what I was 
> giving to YCOORD_CONV.  *sigh*

Is this something to do with the axis range (e.g. !Y.CRANGE) being specified in powers of 
10 rather than regular old absolute units?

paulv

>> Well, it seems that I have figured out my immediate problem.  I 
>> finally have a log plot working!  Turns out that the real problem was 
>> what I was giving to YCOORD_CONV.  *sigh*
> 
> 
> Is this something to do with the axis range (e.g. !Y.CRANGE) being 
> specified in powers of 10 rather than regular old absolute units?

No.  It was purely a programming error on my part.  I typically work in 
normalized coordinates and I was setting YCOORD_CONV in my code, but 
when I did the work for creating a log axis and plot, I forgot to reset 
YCOORD_CONV to match the new data range.  So, I was plotting the data 
and the axis against the first data range (before the log was taken).