Re: [Help-gnucap] Slow at maths while doing tran

[al davis]

On Monday 03 December 2012, address@hidden wrote:
> The issue comes when the circuit becomes bigger and bigger,
> sometimes  the time for gnucap to do the maths to calculate
> the new signal values takes a bit more time.
> So in the gnucap output we have
> 
> >print tran v(nodes)
> >tran 1 1
> >param ParamDev12=10
> >tran | tool
> 
>         #Time -------------------
>         7. ----------------------
>         Wait for 5seconds
>         8. ----------------------

It's probably not math at all, but rather the operating system's 
output buffering.

When using a pipe, the OS buffers it, something like 4096 byte 
blocks.  I tried to override this, but it didn't work reliably.  
That was a Long Time Ago ...  perhaps things have changed.


Sometimes there IS a time delay due to math.  Perhaps there is 
something strange going on then ..  Gnucap might temporarily go 
to a very small time step to get past some kind of issue, then 
go back up to bigger steps.  If this is the case, you might be 
able to see it with "trace all", which is recommended anyway and 
will become the default in the next release.  The command syntax 
is a hangover from Spice syntax, and Spice style step control.  
Gnucap moved on from Spice style step control long ago, but the 
syntax remains.

The old strobe-by-default is a hangover from the days of ASCII 
plots, where you want the data to be uniformly spaced so the 
plot looks decent.