sigmoid_derivative, a Fortran90 code which evaluates derivatives of any order for the sigmoid function s(x)=1/(1+exp(-x)). The test code creates graphics images using gnuplot().


The information on this web page is distributed under the MIT license.


sigmoid_derivative is available in a C version and a C++ version and a Fortran90 version and a MATLAB version and an Octave version and a Python version.

Related Data and Programs:


gnuplot, a Fortran77 code which writes data and command files so that gnuplot() plots the results.

polpak, a Fortran90 code which evaluates a variety of mathematical functions, polynomials, and sequences, including Bell, Benford, Bernoulli, Bernstein, Cardan, Catalan, Charlier, Chebyshev, Collatz, Delannoy, Euler, Fibonacci, Gegenbauer, Gudermannian, Harmonic, Hermite, Hofstadter, Hypergeometric 2F1, Jacobi, Krawtchouk, Laguerre, Lambert W, Legendre, Lerch, Meixner, Mertens, Moebius, Motzkin, Phi, Stirling Numbers, Tau, Tribonacci, Zernike.



  1. Joe McKenna,
    Derivatives of the sigmoid function,

Source Code:

Last revised on 23 May 2024.