- float The estimated integral computed with the composite Simpson's rule. See Also -------- quad : adaptive quadrature using QUADPACK fixed_quad : fixed-order Gaussian quadrature dblquad : double integrals tplquad : triple integrals romb : integrators for sampled data cumulative_trapezoid : cumulative integration for sampled data cumulative_simpson : cumulative integration using Simpson's 1/3 rule Notes ----- For an odd number of samples that are equally spaced the result is exact if the function is a polynomial of order 3 or less. If the samples are not equally spaced, then the result is exact only if the function is a polynomial of order 2 or less. References ---------- .. [1] Cartwright, Kenneth V. Simpson's Rule Cumulative Integration with MS Excel and Irregularly-spaced Data. Journal of Mathematical Sciences and Mathematics Education. 12 (2): 1-9 Examples -------- >>> from scipy import integrate >>> import numpy as np >>> x = np.arange(0, 10) >>> y = np.arange(0, 10) >>> integrate.simpson(y, x=x) 40.5 >>> y = np.power(x, 3) >>> integrate.simpson(y, x=x) 1640.5 >>> integrate.quad(lambda x: x**3, 0, 9)[0] 1640.25 r