I want some minor ticks on the y axis, but it doesn't work. I already tried minor y ticks num but it didn't help. Thank you in advance.
\documentclass[11pt,a4paper,oneside ]{article}
\usepackage[USenglish, german,ngerman]{babel}
\usepackage[utf8x]{luainputenc}
\usepackage{times}
\usepackage[T1]{fontenc}
\usepackage[a4paper, top=2cm, bottom=2cm,left=1cm , right =1cm]{geometry}
\usepackage{pgfplots}
\usepackage{pgfplotstable}
\begin{document}
\begin{tikzpicture}
\begin{axis}[
xmin = 0,
height=10cm,
width=18cm,
ymode=log,
grid = both,
]
coordinates{
(1,2)(2,4)(3,6)(4,8)(5,10)(6,12)(7,14)(8,16)(9,18)(10,20)
};
\end{axis}
\end{tikzpicture}
\end{document}




