README
¶
Package bitmap provides a simple bitmap which allows individual bits to be set and read within a slice of bytes.
The package was inspired by the book "Programming Pearls," by Jon Bentley. The first example in the book is a clever sorting solution which uses a bitmap to sort a file containing up 10 million numeric values in a single pass without loading them all into memory.
http://www.cs.bell-labs.com/cm/cs/pearls/cto.html
func ExampleBitmap () {
b := bitmap.New(10)
b.Set(2)
fmt.Printf("2 in bitmap: %v. 7 in bitmap: %v.\n", b.IsSet(2), b.IsSet(7))
// Output: 2 in bitmap: true. 7 in bitmap: false.
}
func ExampleValues () {
b := bitmap.New(10)
b.Set(2)
b.Set(7)
fmt.Println(b.Values())
// Output: [2 7]
}
Documentation
¶
Overview ¶
Package bitmap provides a simple bitmap which allows individual bits to be set and read within a slice of bytes.
The package was inspired by the book "Programming Pearls," by Jon Bentley. The first example in the book is a clever sorting solution which uses a bitmap to sort a file containing up 10 million numeric values in a single pass without loading them all into memory.
Index ¶
Constants ¶
This section is empty.
Variables ¶
var ErrOutOfRange = errors.New("Value out of range.")
Functions ¶
This section is empty.
Types ¶
type BitMap ¶
type BitMap struct {
// contains filtered or unexported fields
}
BitMap is a struct containing a slice of bytes, being used as a bitmap.
func FromString ¶
func New ¶
New returns a BitMap. It requires a size. A bitmap with a size of eight or less will be one byte in size, and so on.
func (BitMap) IsSet ¶
IsSet returns a boolean indicating whether the bit is set for the position in question.
Source Files