Exact solutions of the nonlocal Hirota equations

Hirota equation has been studied in the past years, which can be used to describe the nonlinear waves in the fluids and nonlinear optical fibers. In this paper, nonlocal Hirota equations with the space (S)-, time (T)- and space-time (ST)-symmetry have been discussed. By virtue of the Hirota bilinear method, higher-order solutions of generalized Hirota equations have been obtained. As the special cases, exact solutions of the S-symmetric, T-symmetric and ST-symmetric nonlocal Hirota equations have been listed. (C) 2019 Elsevier Ltd. All rights reserved.