Wronskian, Pfaffian and periodic wave solutions for a (2+1)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$(2 + 1)$$\end{document}-dimensional extended shallow water wave equation

Under investigation in this paper is a (2+1)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$(2 + 1)$$\end{document}-dimensional extended shallow water wave equation. Bilinear form is obtained via the generalized dependent variable transformation. The Nth-order analytic solutions are, respectively, obtained via the Wronskian and Pfaffian techniques. Soliton solutions are constructed through the Nth-order solutions. Discussions on the propagation of the solitons indicate that the soliton solutions with φ(y)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\varphi (y)$$\end{document} are more general than those without φ(y)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\varphi (y)$$\end{document}, and φ(y)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\varphi (y)$$\end{document} could affect the features of the soliton solutions, where φ(y)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\varphi (y)$$\end{document} is a real function related to the aforementioned transformation. One-periodic wave solutions are obtained via the Hirota–Riemann method. Relation between the one-periodic wave solutions and one-soliton solutions is studied, which indicates that the one-periodic wave solutions can approach to the one-soliton solutions under certain condition.