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.

if

if condition is true (method 1)
local a = true if a then print("a = true") end

if condition is true (method 2)
local a = true if a == true then print("a = true") end

if condition is false
local a = false if a == false then print("a = false") end

else

if condition is not met, then do else
local a = false if a then print("a = true") else print("a = false") end

elseif

if condition is not met, then do elseif
local a = false if a then print("a = true") elseif a == false then print("a = false") end

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.

and

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

or

if condition is true or condition == true then
local a = true if a or a == true then print("a = true") end

not

if condition is not true
local a = false if not a then print("a = false") end

Comparison Operators

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

equal to

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

does not equal

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

greater than or equal to

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

greater than

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

less than or equal to

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

less than

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

add

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

subtract

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

inverse

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

multiply

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

divide

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

power

base of 2, power of 8 (2ⁿ) = 256

local a, b = 2, 16 local result = a ^ b -- generate answer -- break down power function into string result (ignore this code) function power(i1, i2) local val = "" -- clear string --+-- for i = 1, i2 do -- generate the longhand math formula 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 "..a.." & "..b.." = " .. result, power(a,b))

click to enlarge

remainder

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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