Bad math calculations

Charlysole

Hi, i am having some problems with basic math calculations...
Not me, a game with these actors:

There are 7 actors in total
3 for add and 3 for subtract (in real numbers)
1 for display the result

(On touch is pressed)
Actor A adds 10
Actor B adds 1
Actor C adds 0.01

Actor D subtract 10
Actor E subtract 1
Actor F subtract 0.01

F+E+D = 11.01 thats fine
but
11.01 - B - A = 0.01? (suposed to be)
but
NOT FOR ME
Result is 0.0099999999999998

Any explanation?
Thanks!

Hopscotch

@Charlysole, floating point arithmetic errors is common in all computer languages. It is an artifact of its bit representation in memory.

If you need exact numbers, you should always round up to the significant number of decimal places.

Charlysole

Thank you @Hopscotch‌ now i understand why it behaves that way.
Can you teach me how to round up in GS?
This community is awsome, thank you so much

Hopscotch

@Charlysole,

round(x) rounds to an integer

roundTo(x,n) rounds to n decimal places

prec(x,n) rounds to n decimal places and pads with zeros (ideal for displaying numbers)

ceil(x) next biggest integer

floor(x) integer part only