Class MultiBitNums

Class of multiple multi-bit data packed in a C string. The number of bits is fixed to an arbitrary value. For example, it can accommodate 11-bit integers.

Function overview

Integer encoding/decoding (so far only decoding has been implemented):

• Each segment of data is assumed to be multi-bit (fixed-length) unsigned integer in network byte order (big endian).
• Note: integers of the system does not have to be big-endian (Only the binary data is interpreted as unsigned big-endian).

Class Methods

MultiBitNums.new( str, nbit [, nint] )

Creates a new object from a binary data (string) containing multi-bit segments.

ARGUMENTS

• str (String): binary data containing multi-bit data
• nbit (Integer): length in bits of each segments contained in str
• nint (Integer, can be omitted): number of nbit-bit data in str. If omitted, derived automatically from the length of str.

RETURN VALUE

• a MultiBitNums object

ERRORS

• exception is raised if nint is too large for the length of str.

Instance Methods

to_int32str

Converts into a string containing binary data of 32-bit integers of the system. Useful with NArray.

ARGUMENTS

(none)

RETURN VALUE

• a String (Its binary expression depends on the integer expression of the system).

ERRORS

• exception is raised if nbit (see MultiBitNums.new) is greater than 32.

EXAMPLE

mb = MultiBitNums.new(str, nbits)
require "narray"           # download it from RAA at www.ruby-lang.org
ary = NArray.to_na( mb, "int" )  # the data is read into a NArray ary