# Raspberry Pi_Eng_24.4.4 Operation

#### Published Book on Amazon All of IOT Starting with the Latest Raspberry Pi from Beginner to Advanced – Volume 1 All of IOT Starting with the Latest Raspberry Pi from Beginner to Advanced – Volume 2

#### 출판된 한글판 도서 최신 라즈베리파이(Raspberry Pi)로 시작하는 사물인터넷(IOT)의 모든 것 – 초보에서 고급까지 (상) 최신 라즈베리파이(Raspberry Pi)로 시작하는 사물인터넷(IOT)의 모든 것 – 초보에서 고급까지 (하)

### 24.4.4Operation

There are a number of operations supported by PHP as follows:

Arithmetic operation

Assignment operation

Comparison operation

Incremental/ Decremental operation

Logical operation

String operation

Array operation

#### 24.4.4.1Arithmetic Operator

Arithmetic operator is operator that is used for general calculations by using numbers.

 Operator Description & Same as… Example Result + Addition \$x + \$y Sum of \$x and \$y - Subtraction \$x - \$y Difference of \$x and \$y * Multiplication \$x * \$y Product of \$x and \$y / Division \$x / \$y Quotient of \$x and \$y % Modulus \$x % \$y Remainder of \$x divided by \$y ** Exponentiation \$x ** \$y Result of raising \$x to the \$y'th power

#### 24.4.4.2Assignment Operator

An assignment operator is operator that you use to assign value to variable. In PHP, "=" operator is used. It specifies the result of expression on the right to the left operand.

When you want to specify a value to a specific key in array, "=>" operator is used.

 Operator Description & Same as… Example Result x = y The left operand gets set to the value of the expression on the right. x = y x += y Addition. x = x + y x -= y Subtraction. x = x - y x *= y Multiplication. x = x * y x /= y Division. x = x / y x %= y Modulus. x = x % y

[Used Example]

Next is an example of assignment operators



#### 24.4.4.3Comparison Operator

A comparison operator is an operator that compares values of two characters or numbers with each other.

 Operator Description & Same as… Example Result == Equal \$x == \$y Returns true if \$x is equal to \$y === Identical \$x === \$y Returns true if \$x is equal to \$y, and they are of the same type != Not equal \$x != \$y Returns true if \$x is not equal to \$y <> Not equal \$x <> \$y Returns true if \$x is not equal to \$y !== Not identical \$x !== \$y Returns true if \$x is not equal to \$y, or they are not of the same type > Greater than \$x > \$y Returns true if \$x is greater than \$y < Less than \$x < \$y Returns true if \$x is less than \$y >= Greater than or equal to \$x >= \$y Returns true if \$x is greater than or equal to \$y <= Less than or equal to \$x <= \$y Returns true if \$x is less than or equal to \$y

#### 24.4.4.4Incremental/Decremental Operator

An incremental operator increases the value of a variable by one, and a decremental operator decreases the value of a variable by one.

 Operator Description & Same as… Example Result ++\$x Pre-increment. Increments \$x by one, then returns \$x \$x++ Post-increment. Returns \$x, then increments \$x by one --\$x Pre-decrement. Decrements \$x by one, then returns \$x \$x-- Post-decrement. Returns \$x, then decrements \$x by one

#### 24.4.4.5Logical Operator

A logical operator is an operator that combines two conditional statements to create a new logical result..

 Operator Description & Same as… Example Result and And \$x and \$y True if both \$x and \$y are true or Or \$x or \$y True if either \$x or \$y is true xor Xor \$x xor \$y True if either \$x or \$y is true, but not both && And \$x && \$y True if both \$x and \$y are true || Or \$x || \$y True if either \$x or \$y is true ! Not !\$x True if \$x is not true

#### 24.4.4.6String Operator

A string operator is an operator that connects several strings together.

 Operator Description & Same as… Example Result . Concatenation \$txt1 . \$txt2 Concatenation of \$txt1 and \$txt2 .= Concatenation assignment \$txt1 .= \$txt2 Appends \$txt2 to \$txt1

#### 24.4.4.7Array Operator

An array operator is an operator used when comparing arrays.

 Operator Description & Same as… Example Result + Union \$x + \$y Union of \$x and \$y == Equality \$x == \$y Returns true if \$x and \$y have the same key/value pairs === Identity \$x === \$y Returns true if \$x and \$y have the same key/value pairs in the same order and of the same types != Inequality \$x != \$y Returns true if \$x is not equal to \$y <> Inequality \$x <> \$y Returns true if \$x is not equal to \$y !== Non-identity \$x !== \$y Returns true if \$x is not identical to \$y