Operators

Overview

Questions

• What basic operators/operations does Julia define?

Objectives

• SOME OBJECTIVE

Julia, like most other languages, defines a core set of basic arithmetic and bitwise operators for its primitive data types. Most of them are similar to most other languages, but there are some operators that might differ, like the division operator, which which is also differently defined between other languages or even language versions (like in Python 2 vs. 3).

Arithmetic Operators

The following table lists the basic arithmetic operators which are defined on all primitive numeric data types:

Expression	Description	Notes
-a	additive inverse
a + b	addition
a - b	subtraction
a * b	multiplication
a / b	division	division of integers always returns a floating point number
a \ b	inverse divide	same as b/a
a ÷ b	integer division	rounded towards zero; within Julia \div<TAB> produces the ÷ character, otherwise use div(a,b)
a % b	remainder of a÷b
a ^ b	a to the power of b

Julia respects the usual mathematical ordering of operators, e.g.:

JULIA

> 2+3*4
14

and

JULIA

> 3*2^2
12

Boolean Operators

Boolean operators work on the Bool type:

Expression	Description
!a	logical negation
a && b	logical and
a || b	logical or

Note that while these operations do not work on integers:

JULIA

> 1 && 0
ERROR: TypeError: non-boolean (Int64) used in boolean context
Stacktrace:
 [1] top-level scope
   @ REPL[38]:1

Bool is an Integer type and thus, boolean values can be treated as integers (false as 0 and true as 1) where necessary:

JULIA

> 1 + true
2

Bitwise Operators

Bitwise operators work on all primitive integer types:

Expression	Description	Notes
~a	bitwise negation (not)
a & b	bitwise and
a | b	bitwise or
a ⊻ b	bitwise xor	exclusive or; type \xor<TAB>
a ⊼ b	bitwise nand	not and; type \nand<TAB>
a >>> b	logical bitwise shift right	does not preserve sign
a >> b	arithmetic bitwise shift right	preserves sign
a << b	logical/arithmetic bitwise shift left	does not necessarily preserve sign (overflow)

Assigning operators

binary arithmetic and bitwise operators can be appended by an equal sign to produce an operator that assigns the result of the operation to the left operand, e.g.:

JULIA

> a = 1
1

> a += 1
2

> a
2

Numeric Comparisons

Comparisons work like in most other programming languages, with the possible extension to allow also non-ASCII versions of some operators:

Operator	Description	Notes
===	equality
!= or ≠	inequality	type \ne<TAB> to get ≠
<, >	less than, greater than
<= or ≤	less than or equal	type \leq<TAB> to get ≤
>= or ≥	greater than or equal	type \geq<TAB> to get ≥