How to remove the name Chapter with fanchyhdr in Report class

Question

I try

\renewcommand{\chaptermark}[1]{\markboth{#1}{}}

but is not effect.

I need 1.First Chapter on head.

Answer 1

The command works fine. It is explained in the documentation:

\documentclass[english]{report}
\usepackage{fancyhdr}
\pagestyle{fancy}
\renewcommand{\chaptermark}[1]{\markboth{\thechapter.\space#1}{}} 
\begin{document}
\chapter{chaptername here}
text here
\clearpage
text here
\clearpage
text here
\end{document}

The result:

EDIT:

The problem of Regis was a little bit difficult because the definiton was inside a sty-file in a separate command. We solved the problem in a chat-room.