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fixed (~r 0 #:notation 'exponential ....) bugs

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This commit is contained in:
Ryan Culpepper 2013-05-08 09:34:57 -04:00
parent 73232afd99
commit 2f403859a0
2 changed files with 39 additions and 13 deletions
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38
collects/racket/format.rkt
View File

@ -303,6 +303,15 @@
[else (values np N*)])))))
(define (%exponential N-abs base upper? format-exponent significand-precision exactly?)
(cond [(zero? N-abs)
(string-append "0"
(if exactly? "." "")
(if exactly? (make-string significand-precision #\0) "")
(exponent-part 0 format-exponent base))]
[else
(%exponential-nz N-abs base upper? format-exponent significand-precision exactly?)]))
(define (%exponential-nz N-abs base upper? format-exponent significand-precision exactly?)
(define-values (N* e-adjust actual-precision)
(scale N-abs base significand-precision exactly?))
;; hack: from 1234 want "1.234"; convert to "1234", mutate to ".234" after saving "1"
@ -312,19 +321,22 @@
(string-set! digits 0 #\.)
(string-append leading-digit
(if (or exactly? (positive? actual-precision)) digits "")
(cond [(procedure? format-exponent)
(format-exponent exponent)]
[else
(string-append
(cond [(string? format-exponent) format-exponent]
[(= base 10) "e"]
[else (format "*~s^" base)])
(if (negative? exponent) "-" "+")
(%pad (number->string (abs exponent))
#:pad-to 2
#:align 'right
#:left-padding "0"
#:right-padding #f))]))))
(exponent-part exponent format-exponent base))))
(define (exponent-part exponent format-exponent base)
(cond [(procedure? format-exponent)
(format-exponent exponent)]
[else
(string-append
(cond [(string? format-exponent) format-exponent]
[(= base 10) "e"]
[else (format "*~s^" base)])
(if (negative? exponent) "-" "+")
(%pad (number->string (abs exponent))
#:pad-to 2
#:align 'right
#:left-padding "0"
#:right-padding #f))]))
(define (scale N-abs base significand-precision exactly?)
(if (zero? N-abs)

14
collects/tests/racket/format.rkt
View File

@ -231,6 +231,13 @@
(tc (~r #:notation 'positional 3735928559 #:base '(up 16))
"DEADBEEF")
(tc (~r #:notation 'positional 0)
"0")
(tc (~r #:notation 'positional 0 #:precision 4)
"0")
(tc (~r #:notation 'positional 0 #:precision '(= 4))
"0.0000")
;; ~r #:notation 'exponential
(tc (~r 12345 #:precision 3 #:notation 'exponential)
@ -295,3 +302,10 @@
"-34.00")
(tc (~r -33.99508664763296 #:precision '(= 3))
"-33.995")
(tc (~r #:notation 'exponential 0)
"0e+00")
(tc (~r #:notation 'exponential 0 #:precision 4)
"0e+00")
(tc (~r #:notation 'exponential 0 #:precision '(= 4))
"0.0000e+00")