zero, a C code which finds a zero of a scalar function of a scalar variable, by Richard Brent.

The method does not require the use of derivatives, and does not assume that the function is differentiable.


The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.


zero is available in a C version and a C++ version and a FORTRAN90 version and a MATLAB version and a Python version and an R version.

Related Data and Programs:


bisection_rc, a C code which seeks a solution to the equation F(X)=0 using bisection within a user-supplied change of sign interval [A,B]. The procedure is written using reverse communication (RC).

test_zero, a C code which implements test problems for the solution of a single nonlinear equation in one variable.

zero_rc, a C code which seeks solutions of a scalar nonlinear equation f(x) = 0, using reverse communication, by Richard Brent.


Original FORTRAN77 version by Richard Brent; C version by John Burkardt.


  1. Richard Brent,
    Algorithms for Minimization without Derivatives,
    Dover, 2002,
    ISBN: 0-486-41998-3,
    LC: QA402.5.B74.

Source Code:

Last revised on 31 May 2021.