31 August 2007 4:57:44.119 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_o4_x.txt". Quadrature rule W file = "lag_o4_w.txt". Quadrature rule R file = "lag_o4_r.txt". Maximum degree to check = 10 Spatial dimension = 1 Number of points = 4 The quadrature rule to be tested is a Gauss-Laguerre rule of ORDER = 4 with A = 0.00000 OPTION = 0, standard rule: Integral ( A <= x < oo ) exp(-x) f(x) dx is to be approximated by sum ( 1 <= I <= ORDER ) w(i) * f(x(i)). Weights W: w( 1) = 0.6031541043416339 w( 2) = 0.3574186924377997 w( 3) = 0.3888790851500540E-01 w( 4) = 0.5392947055613276E-03 Abscissas X: x( 1) = 0.3225476896193924 x( 2) = 1.745761101158347 x( 3) = 4.536620296921128 x( 4) = 9.395070912301135 Region R: r( 1) = 0.000000000000000 r( 2) = 0.1000000000000000E+31 A Gauss-Laguerre rule would be able to exactly integrate monomials up to and including degree = 7 Error Degree Exponents 0.0000000000000002 0 0 0.0000000000000004 1 1 0.0000000000000004 2 2 0.0000000000000002 3 3 0.0000000000000004 4 4 0.0000000000000004 5 5 0.0000000000000007 6 6 0.0000000000000011 7 7 0.0142857142857130 8 8 0.0650793650793635 9 9 0.1641269841269826 10 10 INT_EXACTNESS_LAGUERRE: Normal end of execution. 31 August 2007 4:57:44.129 PM