fancyhdr - how to disable auto section number and still show section name in header

Question

\documentclass[fleqn,12pt,a4paper]{article}
%\RequirePackage{Kaumudi_Package}
\usepackage{fancyhdr}
\pagestyle{fancy}
\begin{document}
\section{section-1} 
\newpage
\section{section-2}
\end{document}

In the above MWE, section name is placed in the page header which is great. However it also places a number in front of each section. I want to disable the number in front of the section. I managed to do that with \section*{} but that takes it off of the header as well. How can I disable the number in front of section and also show the name of the section in the header

Answer 1

You need to redefine \sectionmark (refer to the package documentation for details); for example, you could use the following:

\documentclass[fleqn,12pt,a4paper]{article}
\usepackage{fancyhdr}

\pagestyle{fancy}
\fancyhead[R]{\leftmark}
\renewcommand\sectionmark[1]{\markboth{\MakeUppercase{#1}}{}}

\begin{document}
\section{section-1}
\newpage
\section{section-2}
\end{document}

After processing the above exampe code you'll get the warning

Package Fancyhdr Warning: \headheight is too small (12.0pt): 
 Make it at least 14.49998pt.
 We now make it that large for the rest of the document.
 This may cause the page layout to be inconsistent, however.

which indicates that the defined header is too big; you can then add to the preamble something like

 \renewcommand\headheight{14.5pt}

To remove the section numbering for the body of the document, you could use \titleformat from the titlesec package:

\documentclass[fleqn,12pt,a4paper]{article}
\usepackage{titlesec}
\usepackage{fancyhdr}

\titleformat{\section}
  {\normalfont\Large\bfseries}{}{0em}{}

\pagestyle{fancy}
\fancyhead[R]{\leftmark}
\renewcommand\sectionmark[1]{\markboth{\MakeUppercase{#1}}{}}
\renewcommand\headheight{14.5pt}

\begin{document}
\section{section-1}
\newpage
\section{section-2}
\end{document}

Is is to be noticed that the above code only suppresses the section numbering in the actual titles, but the numbering will still appear in the ToC and in the lower level sectional units; if the section numbering must be removed from the ToC and from the lower level sectional units, the following lines need to be added to the preamble:

\renewcommand\thesection{}
\renewcommand\thesubsection{\arabic{subsection}}

Answer 2

I would suggest to switch to a newer and more powerfull class like scrartcl which already has suitable commands:

\documentclass[fleqn,12pt,a4paper]{scrartcl} 
\usepackage{fancyhdr} 
\pagestyle{fancy} 
\begin{document} 
\addsec{section-1}  
\newpage 
\addsec{section-2} 
\end{document}