pxt-calliope/olddocs/js/bits.md
2017-03-07 10:17:01 -08:00

2.4 KiB

Bits Library

Functions in the Bits library.

@parent td/language

The binary numeral system represents numeric values using values 0 and 1. This is how almost all modern computers store data. Each 0 or 1 digit is called a binary digit, or bit for short.

The Bits library includes functions for bit-level manipulation of integers. In the Touch Develop editor, click bits to see the following bit functions:

Bitwise and, or, and xor functions

Syntax

bits -> and/or/xor uint32 (x : Number, y : Number) returns Number

Parameters

  • x - an unsigned 32 bit integer Number
  • y - another unsigned 32 bit integer Number

and uint32

performs bitwise AND; returns 1 at position i if both bits x[i] and y[i] are 1, otherwise returns 0.

or uint32

performs bitwise OR; returns 1 at position i if either bit x[i] or y[i] is 1, otherwise returns 0.

xor uint32

performs bitwise exclusive XOR; returns 1 at position i if x[i]=1 and y[i]=0 or x[i] = 0 and y[i] =1; returns 0 otherwise

Rotate left and rotate right

Rotate bits to the left or the right, by the specified number of positions.

Syntax

bits -> rotate left unint32 (x : Number, bits : Number) returns Number

bits -> rotate right unint32 (x : Number, bits : Number) returns Number

Parameters

Shift left and shift right

Shift bits to the left or the right, by the specified number of positions.

Syntax

bits -> shift left unint32 (x : Number, bits : Number) returns Number

bits -> shift right unint32 (x : Number, bits : Number) returns Number

Parameters

See also

statements and operators, math functions, Number