5Oct/0910
Reverse Polish Sausage
by Mike
Image text: It looks good, but it needs more postfixins.
This comic is based on the Reverse Polish notation proposed for use in mathematics. It's also sometimes known as postfix notation because the operators follow all of it's operands. For example, In normal notation if you wanted to add the numbers 3, 4, and 5 you would write 3 + 4 + 5. Using reverse polish notation it would be written as 3 4 5 +.
« Conversations
Surgery »
October 5th, 2009
It can also be 3 4 + 5 +
October 5th, 2009
What Allan said.
Using RPN, the example above could be calculated one of two ways:
3 4 + 5 +
or:
3 4 5 + +
October 9th, 2009
Hah, I remember that being the reason I hated HP graph calculators.
June 20th, 2010
It’s the main reason that i love HP calculators.
Once you’re used to it, it really is the only way to fly.
April 19th, 2010
Postfixins is a pun on postfix (the plus is at the end) and fixin (ketchup, mustard, etc.).
November 2nd, 2010
yeah, so why is the sausage out of the bun? sausage is the operator?
November 25th, 2010
The bun is two arguments (Left half and Right half), not one.
December 25th, 2010
please don’t misplace apostrophes in a website devoted to explaining xkcd.
April 11th, 2011
Ya I agree that once you get used to it, it is the only way to go. Saves some finger work for sure.
September 24th, 2011
“In normal notation if you wanted to add the numbers 3, 4, and 5 you would write 3 + 4 + 5. Using reverse polish notation it would be written as 3 4 5 +”
Actually, it would be written as 3 4 5 ++