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authorshigek <shigek@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2003-04-24 13:37:32 +0000
committershigek <shigek@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2003-04-24 13:37:32 +0000
commitcff57b4a267b61561b04c527b5ce04d64cbcf78b (patch)
tree1196b15571b715ea69fee1ea90ce8bb2e958e787 /ext/bigdecimal/sample
parent558c428b72e666a58d6819cb45b63e75f15ae537 (diff)
Dir. rearrangement according to the suggestions from Minero Aoki.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@3722 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'ext/bigdecimal/sample')
-rw-r--r--ext/bigdecimal/sample/linear.rb46
-rw-r--r--ext/bigdecimal/sample/nlsolve.rb38
-rw-r--r--ext/bigdecimal/sample/pi.rb50
3 files changed, 134 insertions, 0 deletions
diff --git a/ext/bigdecimal/sample/linear.rb b/ext/bigdecimal/sample/linear.rb
new file mode 100644
index 0000000..f93404f
--- /dev/null
+++ b/ext/bigdecimal/sample/linear.rb
@@ -0,0 +1,46 @@
+#!/usr/local/bin/ruby
+
+#
+# linear.rb
+#
+# Solves linear equation system(A*x = b) by LU decomposition method.
+# where A is a coefficient matrix,x is an answer vector,b is a constant vector.
+#
+require "bigdecimal"
+require "ludcmp"
+
+include LUSolve
+
+def rd_order
+ printf("Number of equations ?")
+ n = gets().chomp.to_i
+end
+
+zero = BigDecimal::new("0.0")
+one = BigDecimal::new("1.0")
+
+while (n=rd_order())>0
+ a = []
+ as= []
+ b = []
+ printf("\nEnter coefficient matrix element A[i,j]\n");
+ for i in 0...n do
+ for j in 0...n do
+ printf("A[%d,%d]? ",i,j); s = gets
+ a <<=BigDecimal::new(s);
+ as<<=BigDecimal::new(s);
+ end
+ printf("Contatant vector element b[%d] ? ",i);b<<=BigDecimal::new(gets);
+ end
+ printf "ANS="
+ x = lusolve(a,b,ludecomp(a,n,zero,one),zero)
+ p x
+ printf "A*x-b\n"
+ for i in 0...n do
+ s = zero
+ for j in 0...n do
+ s = s + as[i*n+j]*x[j]
+ end
+ p s-b[i]
+ end
+end
diff --git a/ext/bigdecimal/sample/nlsolve.rb b/ext/bigdecimal/sample/nlsolve.rb
new file mode 100644
index 0000000..08f17f9
--- /dev/null
+++ b/ext/bigdecimal/sample/nlsolve.rb
@@ -0,0 +1,38 @@
+#!/usr/local/bin/ruby
+
+#
+# nlsolve.rb
+# An example for solving nonlinear algebraic equation system.
+#
+
+require "bigdecimal"
+require "newton"
+include Newton
+
+class Function
+ def initialize()
+ @zero = BigDecimal::new("0.0")
+ @one = BigDecimal::new("1.0")
+ @two = BigDecimal::new("2.0")
+ @ten = BigDecimal::new("10.0")
+ @eps = BigDecimal::new("1.0e-16")
+ end
+ def zero;@zero;end
+ def one ;@one ;end
+ def two ;@two ;end
+ def ten ;@ten ;end
+ def eps ;@eps ;end
+ def values(x) # <= defines functions solved
+ f = []
+ f1 = x[0]*x[0] + x[1]*x[1] - @two # f1 = x**2 + y**2 - 2 => 0
+ f2 = x[0] - x[1] # f2 = x - y => 0
+ f <<= f1
+ f <<= f2
+ f
+ end
+end
+ f = BigDecimal::limit(100)
+ f = Function.new
+ x = [f.zero,f.zero] # Initial values
+ n = nlsolve(f,x)
+ p x
diff --git a/ext/bigdecimal/sample/pi.rb b/ext/bigdecimal/sample/pi.rb
new file mode 100644
index 0000000..cbb8448
--- /dev/null
+++ b/ext/bigdecimal/sample/pi.rb
@@ -0,0 +1,50 @@
+#!/usr/local/bin/ruby
+
+#
+# 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.exponent >= exp)
+ t = t*m25
+ u,r = t.div(k,sig)
+ pi = pi + u
+ k = k+two
+ end
+
+ u = BigDecimal::new("1")
+ k = BigDecimal::new("1")
+ w = BigDecimal::new("1")
+ t = BigDecimal::new("956")
+ while (u.exponent >= exp )
+ t,r = t.div(m57121,sig)
+ u,r = t.div(k,sig)
+ pi = pi + u
+ k = k+two
+ end
+ pi
+end
+
+if $0 == __FILE__
+ if ARGV.size == 1
+ print "PI("+ARGV[0]+"):\n"
+ p big_pi(ARGV[0].to_i)
+ else
+ print "TRY: ruby pi.rb 1000 \n"
+ end
+end