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-rw-r--r--vendor/bundle/ruby/3.4.0/gems/bigdecimal-3.2.2/sample/linear.rb74
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diff --git a/vendor/bundle/ruby/3.4.0/gems/bigdecimal-3.2.2/sample/linear.rb b/vendor/bundle/ruby/3.4.0/gems/bigdecimal-3.2.2/sample/linear.rb
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+++ b/vendor/bundle/ruby/3.4.0/gems/bigdecimal-3.2.2/sample/linear.rb
@@ -0,0 +1,74 @@
+#!/usr/local/bin/ruby
+# frozen_string_literal: false
+
+#
+# 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.
+#
+# USAGE:
+# ruby linear.rb [input file solved]
+#
+
+# :stopdoc:
+require "bigdecimal"
+require "bigdecimal/ludcmp"
+
+#
+# NOTE:
+# Change following BigDecimal.limit() if needed.
+BigDecimal.limit(100)
+#
+
+include LUSolve
+def rd_order(na)
+ printf("Number of equations ?") if(na <= 0)
+ n = ARGF.gets().to_i
+end
+
+na = ARGV.size
+zero = BigDecimal("0.0")
+one = BigDecimal("1.0")
+
+while (n=rd_order(na))>0
+ a = []
+ as= []
+ b = []
+ if na <= 0
+ # Read data from console.
+ 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 = ARGF.gets
+ a << BigDecimal(s)
+ as << BigDecimal(s)
+ end
+ printf("Contatant vector element b[%d] ? ",i)
+ b << BigDecimal(ARGF.gets)
+ end
+ else
+ # Read data from specified file.
+ printf("Coefficient matrix and constant vector.\n")
+ for i in 0...n do
+ s = ARGF.gets
+ printf("%d) %s",i,s)
+ s = s.split
+ for j in 0...n do
+ a << BigDecimal(s[j])
+ as << BigDecimal(s[j])
+ end
+ b << BigDecimal(s[n])
+ end
+ end
+ x = lusolve(a,b,ludecomp(a,n,zero,one),zero)
+ printf("Answer(x[i] & (A*x-b)[i]) follows\n")
+ for i in 0...n do
+ printf("x[%d]=%s ",i,x[i].to_s)
+ s = zero
+ for j in 0...n do
+ s = s + as[i*n+j]*x[j]
+ end
+ printf(" & %s\n",(s-b[i]).to_s)
+ end
+end