  We study the 2D Ising model in a complex magnetic field in the vicinity of
the Yang-Lee edge singularity. By using Baxter's variational corner transfer
matrix method combined with analytic techniques, we numerically calculate the
scaling function and obtain an accurate estimate of the location of the
Yang-Lee singularity. The existing series expansions for susceptibility of the
2D Ising model on a triangular lattice by Chan, Guttmann, Nickel and Perk
allowed us to substantially enhance the accuracy of our calculations. Our
results are in excellent agreement with the Ising field theory calculations by
Fonseca, Zamolodchikov and the recent work by Xu and Zamolodchikov. In
particular, we numerically confirm an agreement between the leading singular
behavior of the scaling function and the predictions of the ${\mathcal
M}_{2/5}$ conformal field theory.
