# change the font of chapter title and section title

I am trying to change the font and format of heading using titlesec package. However it gives me the following error.

Missing { inserted \tableofcontents <br>
Missing { inserted \chapter{Introduction}


## The code:

\documentclass[10pt, letterpaper]{report}
\usepackage{thesis}

\usepackage{titlesec}
\renewcommand{\chaptername}{CHAPTER}{\Large}
\titlespacing*{\chapter}{0pt}{0.5in}{0.3in}
\titleformat{\chapter}[display]
{\normalfont\Large\centering\uppercase}{\chaptertitlename\ \thechapter}{0pt}{\Large}
\titleformat{\section}{\large\bfseries}{\thesection}{1em}{}

\begin{document}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\tableofcontents

\chapter{Introduction}

Some text.

\end{document}

-
Note that the renewal of your \chaptername doesn't have the correct format - only 2 arguments are required: \renewcommand{\chaptername}{CHAPTER}. The {\Large} has no meaning within the document preamble. –  Werner Jun 7 '12 at 19:12

\uppercase requires a parameter, which is not supported in this argument of \titleformat. But it's supported within another argument, that's why this works:
\titleformat{\chapter}[display]

Probably \MakeUppercase is better than \uppercase. If one wants to specify more complex management of the title, one can load titlesec with the explicit option and then it's required to specify the title with #1. –  egreg Jun 7 '12 at 20:47