Basic lua: Operators

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

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

does not equal

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

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

greater than

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

less than or equal to

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

less than

if a less than 2
local a = 0 if a < 2 then print("a = " .. a) end

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 )

subtract

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

inverse

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

multiply

2 x 2 = 4
local a = 2 local result = a * a print( result )

divide

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

power

base of 2, power of 8 (2ⁿ) = 256 (2x2=4x2=8x2=16x2=32x2=64x2=128x2=256)

local a, b = 2, 8
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))

remainder

remainder of 25 ÷ 4 = 1 (25 ÷ 4 = 6.25 - 6 = 0.25 * 4 = 1)

local a = 25
local b = 4
local result = a / b -- 25 ÷ 4 = 6.25
local result_decimal = math.fmod(result, 1) -- 6.25 - 6 = 0.25
local result_rounded = math.modf(result) -- 6.25 - 0.25 = 6
local remainder = a % b -- 0.25 * 4 = 1

print("result: " .. result .. ", decimal: " .. result_decimal .. ", rounded: " .. result_rounded .. ", remainder: " .. remainder)

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