/usr/share/doc/ruby-gsl/examples/integration/qag2.rb is in ruby-gsl 2.1.0.3+dfsg1-1build1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 | #!/usr/bin/env ruby
require("gsl")
# Singular at x = 0
f = GSL::Function.alloc { |x| 1.0/Math::sqrt(x) }
puts("QAG")
p f.qag(0, 1)
p f.qag([0, 1])
p GSL::Integration.qag(f, 0, 1)
p GSL::Integration.qag(f, [0, 1])
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