1 September 2007 7:21:09.485 PM INT_EXACTNESS_LAGUERRE FORTRAN90 version Investigate the polynomial exactness of a Gauss-Laguerre quadrature rule by integrating exponentially weighted monomials up to a given degree over the [0,oo) interval. The rule may be defined on another interval, [A,oo) in which case it is adjusted to the [0,oo) interval. INT_EXACTNESS_LAGUERRE: User input: Quadrature rule X file = "lag_o8_modified_x.txt". Quadrature rule W file = "lag_o8_modified_w.txt". Quadrature rule R file = "lag_o8_modified_r.txt". Maximum degree to check = 18 Spatial dimension = 1 Number of points = 8 The quadrature rule to be tested is a Gauss-Laguerre rule of ORDER = 8 with A = 0.00000 OPTION = 1, modified rule: Integral ( A <= x < oo ) f(x) dx is to be approximated by sum ( 1 <= I <= ORDER ) w(i) * f(x(i)). Weights W: w( 1) = 0.4377234104929118 w( 2) = 1.033869347665598 w( 3) = 1.669709765658776 w( 4) = 2.376924701758599 w( 5) = 3.208540913347924 w( 6) = 4.268575510825132 w( 7) = 5.818083368671924 w( 8) = 8.906226215292206 Abscissas X: x( 1) = 0.1702796323051010 x( 2) = 0.9037017767993800 x( 3) = 2.251086629866131 x( 4) = 4.266700170287659 x( 5) = 7.045905402393466 x( 6) = 10.75851601018100 x( 7) = 15.74067864127800 x( 8) = 22.86313173688927 Region R: r( 1) = 0.000000000000000 r( 2) = 0.1797693134862000 A Gauss-Laguerre rule would be able to exactly integrate monomials up to and including degree = 15 Error Degree Exponents 0.0000000000000004 0 0 0.0000000000000002 1 1 0.0000000000000001 2 2 0.0000000000000001 3 3 0.0000000000000003 4 4 0.0000000000000006 5 5 0.0000000000000007 6 6 0.0000000000000008 7 7 0.0000000000000006 8 8 0.0000000000000003 9 9 0.0000000000000002 10 10 0.0000000000000004 11 11 0.0000000000000004 12 12 0.0000000000000007 13 13 0.0000000000000004 14 14 0.0000000000000002 15 15 0.0000777000777002 16 16 0.0006627359568542 17 17 0.0029866284768253 18 18 INT_EXACTNESS_LAGUERRE: Normal end of execution. 1 September 2007 7:21:09.510 PM