  We investigate numerical solution of the Dokshitzer-Gribov-Lipatov-Altarelli-
Parisi (DGLAP) Q^2 evolution equation for the transversity distribution Delta_T
q or the structure function h_1. The leading-order (LO) and next-to-
leading-order (NLO) evolution equations are studied. The renormalization scheme
is MS or overline{MS} in the NLO case. Dividing the variables x and Q^2 into
small steps, we solve the integrodifferential equations by the Euler method in
the variable Q^2 and by the Simpson method in the variable x. Numerical results
indicate that accuracy is better than 1% in the region 10^{-5}<x<0.8 if more
than fifty Q^2 steps and more than five hundred x steps are taken. We provide a
FORTRAN program for the Q^2 evolution and devolution of the transversity
distribution Delta_T q or h_1. Using the program, we show the LO and NLO
evolution results of the valence-quark distribution Delta_T u_v + Delta_T d_v,
the singlet distribution sum_i (Delta_T q_i + Delta_T qbar_i), and the flavor
asymmetric distribution Delta_T ubar - Delta_T dbar.They are also compared with
the longitudinal evolution results.
