source: trunk/SRC/ToBeReviewed/LECTURE/inverse_binary.pro @ 114

;+
; NAME: inverse_binary
;
; PURPOSE: inverse function of the binary.pro function => given a
; input array of 0/1, return its corresponding byte/integer/long
; representation
;
; CATEGORY:
;
; CALLING SEQUENCE: res = inverse_binary(binnum)
;
; INPUTS: 
;    binnum must be a binary type array containing only 0 and 1.
;    According to binary.pro outputs, binnum array must have the
;    following dimensions values: (8, t, d1, d2...)
;    t gives the output type: t = 1 -> byte
;                             t = 2 -> integer
;                             t = 4 -> long
;    
;     (d1, d2...) are the output dimensions
;
; KEYWORD PARAMETERS: no
;
; OUTPUTS: a byte/integer/long array with (d1, d2...) dimensions
;
; COMMON BLOCKS: no
;
; RESTRICTIONS:the binary number can represent only byte/integer/long
;
; EXAMPLE:
;
;     IDL> a=indgen(5)
;     IDL> b=binary(a)
;     IDL> help, b
;     B               BYTE      = Array[8, 2, 5]
;     IDL> print, b
;        0   0   0   0   0   0   0   0
;        0   0   0   0   0   0   0   0
;     
;        0   0   0   0   0   0   0   0
;        0   0   0   0   0   0   0   1
;     
;        0   0   0   0   0   0   0   0
;        0   0   0   0   0   0   1   0
;     
;        0   0   0   0   0   0   0   0
;        0   0   0   0   0   0   1   1
;     
;        0   0   0   0   0   0   0   0
;        0   0   0   0   0   1   0   0
;     IDL> help, inverse_binary(b)
;     <Expression>    INT       = Array[5]
;     IDL> print, inverse_binary(b)
;            0       1       2       3       4
;
; MODIFICATION HISTORY:
;      Sebastien Masson (smasson@jamstec.go.jp)
;      July 2004
;-
;------------------------------------------------------
;------------------------------------------------------
FUNCTION inverse_binary, binnumb
;
;
  compile_opt idl2, strictarrsubs
;
  s = size(binnumb, /dimensions)
  IF n_elements(s) EQ 1 THEN numbofbit = 8 ELSE numbofbit = 8*s[1]
  nvalues = n_elements(binnumb)/numbofbit
  bn = reform(long(binnumb), numbofbit, nvalues)
;
  CASE numbofbit OF
    8:res = byte(total(temporary(bn)*2b^reverse(indgen(numbofbit)#replicate(1b, nvalues), 1), 1))
    16:res = fix(total(temporary(bn)*2^reverse(indgen(numbofbit)#replicate(1, nvalues), 1), 1, /double))
    32:res = long(total(temporary(bn)*2L^reverse(indgen(numbofbit)#replicate(1L, nvalues), 1), 1, /double))
  ENDCASE
;
  CASE n_elements(s) OF
    1:res = res[0]
    2:res = res[0]
    3:
    ELSE:res = reform(res, s[2:n_elements(s)-1], /over)
  ENDCASE
;
  return, res
end