How do I get a calculation that can't be lower than 0?

How can I phrase a calculation in a Roll20 character sheet to get a value that is never lower than 0? I'd prefer an If-function, but what I want is this: A - B = C, where C must be 0 if A is lower than B. I've looked at D&D sheets that have a maximum Dex-bonus for AC, but I can't quite figure out how it works. I'd appreciate any assistance.

You can use the Grouping syntax for this: [[ {(A-B),0}kh1 ]] Some things to remember: { } Defines a group. You can have 1 or more things in a group. By default, they will be summed. [[ {2,3} ]] will be 5. Items in a group must be either dice rolls or numbers, you can't have both. If you have dice and you need to specify a constant, you can use 0d0 for 0, or #d1 for some #, like 5d1 for 5. k# Modifies the group to be keeping some values from the set, the # determines how many. Alternatively, you can use d# to mean drop # values. h Modifies the keeping instruction to keep (or drop) from the highest end ( h is the default behavior for keep if it is omitted) You can also use l to keep (or drop) from the lowest end ( l is the default behavior for drop if it is omitted)

Thank you! That makes sense.

If you need a math-only solution for an auto-calc field, you can use the max calculation: If x &gt; y, the result is x, while if x &lt; y, the result is y (((@{x} + @{y}) + abs(@{x} - @{y})) / 2) If you ever need the min value instead, that is (((@{x} + @{y}) - abs(@{x} - @{y})) / 2) . from the CSS-Wizardry thread (<a href="https://app.roll20.net/forum/post/882997/#post-944536" rel="nofollow">https://app.roll20.net/forum/post/882997/#post-944536</a> ) On the 3.5 character sheet, I used a much more complicated equation which handles comparing negatives to each other better (and because I needed 'give me C if A is bigger than B else give me B'). If you want that one, let me know and I'll simplify it back down for you. :) Hope that helps.

Ok, so what is the difference then? Is there a benefit of using a math-only solution?

Math-only solutions are for parts of character sheets where you can't use a roll. Ie calculating the dexterity bonus from the base dexterity to display it on a character sheet. Or calculating whether the dex bonus or the max dex bonus from armor is higher. Those calculation fields built into a character sheet can't/don't use rolls for their calculations so using the kh1 roll syntax doesn't work; you'd just get to see the equation. If what you are doing is part of a roll or a macro, the kh1/kl1 solution is superior; it's easier to read if nothing else. I wasn't certain if you were working on building a custom character sheet (and so might need a math-only solution) or working on a macro to run from a character sheet. As a Mentor, it could be either. :D

I'm trying to make a custome character sheet. I guess I shall have to try to figure out how to use the formula you provided Diana, since this is for an auto-calculating field. Thank you your the assistance. The formula is meant to calculate encumbrance penalties. In the system I'm using, characters suffer a -1 speed penalty per 50 units of weight carried in excess of their carrying capacity. This is one reason why I need the formula.

*nod* If you are wanting to make sure that your delta between the carrying capacity and the current weight carried is never negative (this will give a zero if your delta is negative: (((A + 0) + abs(A - 0)) / 2) where A is Current Weight Carried - Weight Capacity Limit Hope that helps. :)

Indeed it helps tremendously! Thank you!