[simonjgreen]

If you want to get a really good feel for these functions, you can do worse than pick up a financial RPN calculator like the HP 12C. It is largely unchanged since it was introduced in the early 80s but it’s highly functional aesthetic and purpose make for a great experience if you like to learn something new that is also genuinely useful. Personally, I keep one of these in my bag. It’s great for meetings where financials are on the table and you also don’t want the distraction of a full desktop OS around you.

[nocoiner]

This is good advice. Also running a quick function can be quicker than opening up excel, fiddling with a cell, etc. (my excel skills are obviously at-best rudimentary). And it’s a cool moment when RPN finally “clicks” and figure out how to perform sequential operations in it without having to rely on increasingly nested parentheses.

[wombatpm]

RPN is great. Start at the deepest level and work your way up.

I used to load my HP15c with common formula for engineering and a basic polynomial root finder.

[bvan]

Unfortunately, these have disappeared from trading floors. Mine is under lock and key.. I sometimes take it or an HP 41 out and place it on my desk just to see the horrified looks on twentysomething’s faces.

[macintux]

I had a small collection of RPN calculators, one or two non-HP, but alas someone broke into my house and took them. I really should have called around to pawn shops after, I’d very much like to have them back.