25 February 2008 12:13:15.259 PM INT_EXACTNESS_GEGENBAUER FORTRAN90 version Investigate the polynomial exactness of a Gauss-Gegenbauer quadrature rule by integrating weighted monomials up to a given degree over the [-1,+1] interval. INT_EXACTNESS_GEGENBAUER: User input: Quadrature rule X file = "gegen_o4_a0.5_x.txt". Quadrature rule W file = "gegen_o4_a0.5_w.txt". Quadrature rule R file = "gegen_o4_a0.5_r.txt". Maximum degree to check = 10 Exponent of (1-x^2), ALPHA = 0.500000 Spatial dimension = 1 Number of points = 4 The quadrature rule to be tested is a Gauss-Gegenbauer rule ORDER = 4 ALPHA = 0.500000 Standard rule: Integral ( -1 <= x <= +1 ) (1-x^2)^alpha f(x) dx is to be approximated by sum ( 1 <= I <= ORDER ) w(i) * f(x(i)). Weights W: w( 1) = 0.2170787134227060 w( 2) = 0.5683194499747424 w( 3) = 0.5683194499747424 w( 4) = 0.2170787134227060 Abscissas X: x( 1) = -0.8090169943749475 x( 2) = -0.3090169943749475 x( 3) = 0.3090169943749474 x( 4) = 0.8090169943749475 Region R: r( 1) = -1.0000000000000000 r( 2) = 1.0000000000000000 A Gauss-Gegenbauer rule would be able to exactly integrate monomials up to and including degree = 7 Error Degree Exponents 0.0000000000000007 0 0 0.0000000000000001 1 1 0.0000000000000001 2 2 0.0000000000000000 3 3 0.0000000000000004 4 4 0.0000000000000000 5 5 0.0000000000000001 6 6 0.0000000000000000 7 7 0.0714285714285717 8 8 0.0000000000000000 9 9 0.1904761904761884 10 10 INT_EXACTNESS_GEGENBAUER: Normal end of execution. 25 February 2008 12:13:15.266 PM