Don,
The TOS software is really quite ingenious. ON the page that shows the option chain, there is a pull-down button that morphs the option chain to any spread imaginable(vertial, ratio, calendar,straddle,strange,iron condor,butterfly,u name it, also a +1,+2 month for a 3 mo calendar e.g.) Then u click on the desired strikes and click analyze.
Don't even get me started on this gem!lol Anyway, you can peep the p&l graph adjusting any parameter u wish(vols,interest rate, time,underlying price,etc) and contort the graph any which way. There are also other tabs which show a probability analysis of touching & expiring. But wait, there's more(I feel like I'm selling a Ronco, SEt it and FORGET IT!)
Another tab depicts the volatility skew across various strikes and time series.
What I mention is actually just the tip of the iceburg as far as their functionality goes. I hope this helps answer your question. btw, I am not affiliated with TOS besides a happy customer
