nx_f64_quad.nx

nx_f64_quad.nx -- GAMS-H: sovereign numerical QUADRATURE (the integration class). Composite Simpson's rule (O(h^4)) over a sign... over a function-id dispatch (no fn pointers in the dialect); qf_eval composes our PROVEN kernels (x^2 / sin / exp / 1/x). integral_a^b f dx ~= h/3 [ f0 + 4(f1+f3+..) + 2(f2+f4+..) + fn ], h=(b-a)/n, n even. f64 software-IEEE; node x_i = a + i*h built from an exact integer-as-f64 (no drift). (Gauss-Legendre / adaptive Gauss-Kronrod = the accuracy/perf upgrade -- its nodes are Legendre roots, computable by composing the new nx_f64_rootfind.) module: nishi-core.math.f64_quad depends: nishi-core.math.f64, nishi-core.math.f64_exp, nishi-core.math.f64_sincos capability: F64_QUADRATURE_SIMPSON license_tier: ORIGINAL