Basic lua: Operators

Lua operators are expressions used to perform calculations or to pass arguments between different value types.

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Conditional Operators

if	Query if something does or does not meet a certain condition.
else	Do something else if the query condition was not met.
elseif	Used to add additional if queries, if the initial query condition was not met.
end	This is used to close various queries or functions; there must be the same amount of end as if; except in instances where elseif has been used.

Example 1: if condition is true (method 1)
local a = true if a then print("a = true") end	click to enlarge

Example 2: if condition is true (method 2)
local a = true if a == true then print("a = true") end	click to enlarge

Example 3: if condition is false
local a = false if a == false then print("a = false") end	click to enlarge

Example 4: if condition is not met, then do else
local a = false if a then print("a = true") else print("a = false") end	click to enlarge

Example 5: if condition is not met, then do elseif
local a = false if a then print("a = true") elseif not a then print("a = false") end	click to enlarge

Logical Operators

and	Allows you to check multiple conditions in a single if query.
or	Allows you to add an alternative if query into a single if query.
not	Checks if condition equals false or negative.

Example 1: if condition a is true and condition b is false then
local a = true local b = false if a == true and b == false then print("a = true", "b=false") end	click to enlarge

Example 2: if condition is true or condition == true then
local a = true if a or a == true then print("a = true") end	click to enlarge

Example 3: if condition is not true
local a = false if not a then print("a = false") end	click to enlarge

Comparison Operators

==	Equal to.
~=	Does not equal.
>=	Greater than or equal to.
>	Greater than.
<=	Less than or equal to.
<	Less than.

Example 1: if a equals 1
local a = 1 if a == 1 then print("a = 1") end	click to enlarge

Example 2: if a does not equal 2
local a = 1 if a ~= 2 then print("a = " .. a) end	click to enlarge

Example 3: if a is greater than or equal to 2
local a = 5 if a >= 2 then print("a = " .. a) end	click to enlarge

Example 4: if a is greater than 2
local a = 3 if a > 2 then print("a = " .. a) end	click to enlarge

Example 5: if a less than or equal to 2
local a = 2 if a <= 2 then print("a = " .. a) end	click to enlarge

Example 6: if a less than 2
local a = 0 if a < 2 then print("a = " .. a) end	click to enlarge

Mathematical Operators

+	Add
-	Subtract or invert
*	Multiply
/	Divide
^	Power
%	Remainder

Example 1: 1 +2 = 3
local a = 1 local b = 2 local result = a + b print( result )	click to enlarge

Example 2: 3 - 2 = 1
local a = 3 local b = 2 local result = a - b print( result )	click to enlarge

Example 3: inversed values
local a = 3 local result = -a print( "original value: " .. a, "inversed value: " .. result )	click to enlarge

Example 4: 2 x 2 = 4
local a = 2 local result = a * a print( result )	click to enlarge

Example 5: 10 ÷ 5 = 2
local a = 10 local b = 5 local result = a / b print( result )	click to enlarge

Example 6: base of 2, power of 8 (2ⁿ) = 256
local a = 2 local b = 8 local result = 2 ^ 8 -- break down power function into string result (ignore this code) function power(i1, i2) local val = "" --+-- for i = 1, i2 do if i < i2 then val = val..i1.."*" else val = val..i1 end end return "which is the equivalent of " .. val end print("power value of 2 & 8 = " .. result, power(a,b))	click to enlarge

Example 7: remainder of 25 ÷ 4 = 1
local a = 25 local b = 4 local result = a / 4 local remainder = a % b local decimal = remainder / b print("result: 25 ÷ 4 = " .. result, "remainder: .25 x 4 = " .. remainder, "decimal: 1 ÷ 4 = " .. decimal )	click to enlarge

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