[General] math

[kevs926]

mC is an integer
(1.+mC/ 3.)

how does this expression evaluated in war3? addition or division first?

 

[Dr Super Good]

JASS performs division before addition. Division and multiplication are equal precedence and performed before addition and subtraction.

 

[kevs926]

are you sure? theres a space between / and 3 though, it might mean something. Also, the dots.. what could it mean?

 

[Nichilus]

In most programming languages, white space has no impact on instruction execution.
I would imagine it's same for jass

 

[Wietlol]

Try it?
Make a new map and make a trigger for map initialization that sends a message to all players with the outcome.
That solves your question and maybe more questions that you have

In this case, diversion comes before addition. spaces are actually neccesary for certain things in JASS equal as is a newline. but in this case it wont matter.

 

[PurgeandFire]

The dots indicate that it is dividing by a float (a real in JASS).

"1." is equivalent to "1.0". It is usually used to perform a calculation with floats rather than integers. For example, if you divide an integer by an integer (e.g. 5 / 3), you'll end up with an integer (1) rather than 1.666. If you add the dot after the divisor, then you'll be guaranteed the decimal result.

 

[Chaosy]

Normal math rules apply.

() > / or * > + or -

However GUI automatically creates () so if you do the math in GUI it could potentially give incorrect results.

are you sure? theres a space between / and 3 though, it might mean something. Also, the dots.. what could it mean?

Spaces do nothing. You can write 3 + 5 in jass the answer will be same as 3+5.

I suppose you mean if the answer becomes .x?

If you get the answer .33 the answer is 0.33

 

[kevs926]

thanks all

 

[Shoto]

Normal math rules apply.

() > / or * > + or -

However GUI automatically creates () so if you do the math in GUI it could potentially give incorrect results.

Sorry for semi-necroing this thread, but I'm curious about the math.
Say I have this expression: 600/2*0,02
Will it evaluate to (600/2)*0,02=6
or will it evaluate to 600/(2*0,02)=15000 if written without brackets? Why?

 

[IcemanBo]

The result is ok.

600/2*0,02:
Step1: 600/2 = 300
Step2: 300*0.02 = 6

600/(2*0,02):
Step1: 2*0.02 = 0.04
Step2: 600/0.04 = 15000

 

[Cokemonkey11]

it will be 6.0, not 6

 

[edo494]

I will also add to this

If 2 expressions are of the same weight(2 multiplications next to each other, multiplication then division etc) then they are always evaluated left to right.

So: 5+3+7*9/3+8-7 will be the same as ((5+3)+((7*9)/3)+8)-7, the result is 30 btw

 

[Shoto]

I will also add to this

If 2 expressions are of the same weight(2 multiplications next to each other, multiplication then division etc) then they are always evaluated left to right.

So: 5+3+7*9/3+8-7 will be the same as ((5+3)+((7*9)/3)+8)-7, the result is 30 btw

Thanks! Great answer!

 

[Dr Super Good]

The "real" type in JASS is actually the C "float" type. As such there is a limited precision and many decimal numbers cannot be represented exactly.

 

[kevs926]

multi or divi has no difference, whether who will come first. answer always same

pure multi and divi expression can be evaluated in anyway

 

[Dr Super Good]

multi or divi has no difference, whether who will come first. answer always same

pure multi and divi expression can be evaluated in anyway

No...
They are evaluated exactly how you do them mathematically. You evaluate them from left to right. This applies to all operations of the same precedence (such as + and -).

 

[edo494]

The importance of knowing left to right instead of "anyway" e.g. right to left is when you deal with more than numbers.

set i = SomeFunction() * someOtherFunction()

Lets say SomeFunction creates some unit and stores it in some global variable and then returns some integer or real value. Then someOtherFunction will try to do something to the unit and return some other value.

If there was no guarantee of Left to right execution, this code would have potential to not even work because if evaluated right to left you will try to manip unit that does not exist and only then you will actually try to create the unit.

Just example of course

 

[Dr Super Good]

Another example is simply involving numbers.

set i = 11 * 3 / 7 * 5
// Equivalent with bracers for explicit ordering.
set i = (((11 * 3) / 7) * 5)

The variable "i" would become equal to 20. This is because the '*' and '/' operators have the same precedence so are evaluated from left to right.

If it was evaluated any other way it would be 0 since the result of integer division of a small number by a larger number is 0.