Created
November 11, 2013 07:29
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hex2signed function written in Gauche
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(define bit-reversal | |
(lambda (str) | |
(let inner ((len (string-length str)) (instr str) (outstr "")) | |
(if (eq? 0 len) | |
outstr | |
(inner (- len 1) | |
(substring instr 1 (string-length instr)) | |
(string-append outstr | |
(cond ((string=? (substring instr 0 1) "0") "1") | |
((string=? (substring instr 0 1) "1") "0")))))))) | |
(define bit2signed | |
(lambda (str) | |
(cond ((string=? "1" (substring str 0 1)) | |
(* -1.0 (+ 1 (string->number (string-append "#b" (bit-reversal (substring str 1 (string-length str)))))))) | |
(else | |
(* 1.0 (string->number (string-append "#b" (substring str 1 (string-length str))))))))) |
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