diff options
| -rw-r--r-- | ext/bigdecimal/sample/pi.rb | 42 |
1 files changed, 6 insertions, 36 deletions
diff --git a/ext/bigdecimal/sample/pi.rb b/ext/bigdecimal/sample/pi.rb index 833967a583..2f7dd27d60 100644 --- a/ext/bigdecimal/sample/pi.rb +++ b/ext/bigdecimal/sample/pi.rb @@ -3,48 +3,18 @@ # # pi.rb # - -require "bigdecimal" -# # Calculates 3.1415.... (the number of times that a circle's diameter # will fit around the circle) using J. Machin's formula. # -def big_pi(sig) # sig: Number of significant figures - exp = -sig - pi = BigDecimal::new("0") - two = BigDecimal::new("2") - m25 = BigDecimal::new("-0.04") - m57121 = BigDecimal::new("-57121") - u = BigDecimal::new("1") - k = BigDecimal::new("1") - w = BigDecimal::new("1") - t = BigDecimal::new("-80") - while (u.nonzero? && u.exponent >= exp) - t = t*m25 - u = t.div(k,sig) - pi = pi + u - k = k+two - end +require "bigdecimal" +require "bigdecimal/math.rb" - u = BigDecimal::new("1") - k = BigDecimal::new("1") - w = BigDecimal::new("1") - t = BigDecimal::new("956") - while (u.nonzero? && u.exponent >= exp ) - t = t.div(m57121,sig) - u = t.div(k,sig) - pi = pi + u - k = k+two - end - pi -end +include BigMath -if $0 == __FILE__ - if ARGV.size == 1 +if ARGV.size == 1 print "PI("+ARGV[0]+"):\n" - p big_pi(ARGV[0].to_i) - else + p PI(ARGV[0].to_i) +else print "TRY: ruby pi.rb 1000 \n" - end end |