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Highlights from
Special Functions math library

  • bern(n) Bern Bernoulli number
  • betad(z) BETAD Dirichlet Beta function
  • binomial(n,d) BINOMIAL calculate the binomial coefficient
  • deta(z,k) DETA Calculates Dirichlet functions of the form
  • erfz(zz) ERFZ Error function for complex inputs
  • eta(z) ETA Dirichlet Eta function
  • euler(n) Euler Euler number
  • eulergamma Euler-Mascheroni constant = -Psi(1) = 0.5772156649015328606...
  • fact(n) FACT Vectorized Factorial function
  • factd(n) FACTD Double Factorial function = n!!
  • gamma(z) GAMMA Gamma function valid in the entire complex plane.
  • gammaln(z) GAMMALOG Natural Log of the Gamma function valid in the entire complex plane.
  • genocchi(z) Genocchi number
  • harm(z) Harm Harmonic sum function valid in the entire (complex) plane.
  • lambda(z) LAMBDA Dirichlet Lambda function
  • poch(z,n)
  • psi(z) Psi Psi (or Digamma) function valid in the entire complex plane.
  • psin(n,z) Psin Arbitrary order Polygamma function valid in the entire complex plane.
  • totient(n) TOTIENT calculates the totient function (also
  • zeta(z) ZETA Riemann Zeta function
  • View all files
from Special Functions math library by Paul Godfrey
Collection of Special Functions programs.

zeta(z)
function [f] = zeta(z)
%ZETA  Riemann Zeta function
%
%usage: f = zeta(z)
%
%tested on version 5.3.1
%
%      This program calculates the Riemann Zeta function
%      for the elements of Z using the Dirichlet deta function.
%      Z may be complex and any size. Best accuracy for abs(z)<80.
%
%      Has a pole at z=1, zeros for z=(-even integers),
%      infinite number of zeros for z=1/2+i*y
%
%
%see also: Eta, Deta, Lambda, Betad, Bern, Euler
%see also: mhelp zeta

%Paul Godfrey
%pgodfrey@conexant.com
%3-24-01

zz=2.^z;
k = zz./(zz-2);

f=k.*deta(z,1);

p=find(z==1);
if ~isempty(p)
   f(p)=Inf;
end

return

%a demo of this function is

ezplot zeta
grid on

figure(2)
ezmesh('abs(zeta(x+i*y))',[0 1 .5 30])
view(75, 4)

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