/usr/share/doc/ruby-gsl/examples/matrix/diagonal.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 14 15 16 17 18 19 20 21 22 23 | #!/usr/bin/env ruby
# Turn on warnings
$-w = true
require 'irb/xmp'
require 'gsl'
# Apparently, IRB::Frame has a bug that prevents the defaults from working, so
# an XMP instance must be created explicitly this way instead of using the
# otherwise convenient xmp method.
XMP.new(IRB::Frame.top(-1)).puts <<END
# Create matrix with diagonal given by Range
GSL::Matrix.diagonal(1..3)
# Create matrix with diagonal given by Array
GSL::Matrix.diagonal([1, 2, 3])
# Create matrix with diagonal given by GSL::Vector
GSL::Matrix.diagonal(GSL::Vector.indgen(3,1))
# Create matrix with diagonal given by individual elements
GSL::Matrix.diagonal(1, 2, 3)
END
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