Numerical integration/Gauss-Legendre Quadrature: Difference between revisions

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m (→‎{{header|C++}}: includes added)
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Does not quite perform the task quite as specified since the node count, N, is set at compile time (to avoid heap allocation) so cannot be passed as a parameter.
Does not quite perform the task quite as specified since the node count, N, is set at compile time (to avoid heap allocation) so cannot be passed as a parameter.
<lang cpp>
<lang cpp>#include <iostream>
#include <iomanip>
#include <cmath>

namespace Rosetta {
namespace Rosetta {


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out << ' ' << legpoly.root(i);
out << ' ' << legpoly.root(i);
}
}
out << '\n';
out << std::endl;
out << "Weights:";
out << "Weights:";
for (int i = 0; i <= eDEGREE; ++i) {
for (int i = 0; i <= eDEGREE; ++i) {
out << ' ' << legpoly.weight(i);
out << ' ' << legpoly.weight(i);
}
}
out << '\n';
out << std::endl;
}
}
private:
private:
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gl5.print_roots_and_weights(std::cout);
gl5.print_roots_and_weights(std::cout);
std::cout << "Integrating Exp(X) over [-3, 3]: " << gl5.integrate(-3., 3., RosettaExp) << '\n';
std::cout << "Integrating Exp(X) over [-3, 3]: " << gl5.integrate(-3., 3., RosettaExp) << std::endl;
std::cout << "Actual value: " << RosettaExp(3) - RosettaExp(-3) << '\n';
std::cout << "Actual value: " << RosettaExp(3) - RosettaExp(-3) << std::endl;
⚫
}</lang>
}
⚫
</lang>


{{out}}
{{out}}
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