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32 lines
845 B
C++
32 lines
845 B
C++
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// Copyright (C) 2008-2012 Lorenzo Caminiti
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// Distributed under the Boost Software License, Version 1.0
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// (see accompanying file LICENSE_1_0.txt or a copy at
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// http://www.boost.org/LICENSE_1_0.txt)
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// Home at http://sourceforge.net/projects/contractpp
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//[n1962_sqrt
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// File: sqrt.cpp
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#include <contract.hpp>
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#include <boost/detail/lightweight_test.hpp>
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#include <cmath>
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CONTRACT_FUNCTION( // Default value for `precision` parameter.
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double (mysqrt) ( double x, double precision, default(1e-6) )
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precondition( x >= 0.0 )
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postcondition(
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auto root = return, // Result value named `root`.
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fabs(root * root - x) <= precision // Equal within precision.
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)
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) {
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return sqrt(x);
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}
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int main ( void )
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{
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BOOST_TEST(fabs(mysqrt(4.0) - 2.0) <= 1e-6);
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return boost::report_errors();
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}
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//]
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