From: lionel.perrin@... Date: 2017-07-19T09:50:55+00:00 Subject: [ruby-core:82107] [Ruby trunk Bug#13754] bigdecimal with lower precision that Float Issue #13754 has been reported by lionel_perrin (Lionel PERRIN). ---------------------------------------- Bug #13754: bigdecimal with lower precision that Float https://bugs.ruby-lang.org/issues/13754 * Author: lionel_perrin (Lionel PERRIN) * Status: Open * Priority: Normal * Assignee: * Target version: * ruby -v: ruby 2.4.1p111 (2017-03-22 revision 58053) [x64-mingw32] * Backport: 2.2: UNKNOWN, 2.3: UNKNOWN, 2.4: UNKNOWN ---------------------------------------- Hello, I'm not sure if I've misunderstood the bigdecimal class but in the following example, I only get 12 significant digits using bigdecimal while using Float, I get a correct value with 17 significant digits. ~~~ ruby # using floats 101/0.9163472602589686 # 110.22022368622177 (OK: floating point computation) # using bigdecimal a = BigDecimal('101'); a.precs # [9, 18] b = BigDecimal('0.9163472602589686'); b.precs # [18, 27] c = a/b; c.precs # [18, 36] (OK: I understand that c is computed with 18 significant digits) c.to_s # "0.110220223686e3" (Mmm: I see only 12 significant digits) c - BigDecimal('0.110220223686e3') # 0.0 (Looks like only 12 significant digits were kept c and not 18) ~~~ Using the Rational class, I've seen that the value I'm expecting is about: 110.2202236862217746799312 -- https://bugs.ruby-lang.org/ Unsubscribe: