qk15 qk15_r qk21 qk21_r qk31 qk31_r qk41 qk41_r qk51 qk51_r qk61 qk61_r

qk41() void qk41 ( double(*)(double)  f, double  a, double  b, double *  result, double *  abserr, double *  resabs, double *  resasc  ) Finite interval quadrature (41 point Gauss-Kronrod rule) Purpose This routine computes   I = integral of f over [a, b] with error estimate, and   J = integral of abs(f) over [a, b], where f is a given function defined by a user supplied subroutine. The integral will be evaluated with the 41 point Gauss-Kronrod rule. Parameters [in] f The user supplied subroutine which calculates the integrand function f(x) defined as follows. double f(double x) { return computed f(x) value } [in] a Lower limit of integration. [in] b Upper limit of integration. [out] result Approximation to I = integral of f over [a, b]. [out] abserr Estimate of the modulus of the absolute error, which should equal or exceed the true error. [out] resabs Approximation to J = integral of abs(f) over [a, b]. [out] resasc Approximation to the integral of abs(f - I/(b - a)) over [a, b]. Reference SLATEC (QUADPACK)