diff --git a/doc/user/analysis.tex b/doc/user/analysis.tex
index aebbcff303..054594af8d 100644
--- a/doc/user/analysis.tex
+++ b/doc/user/analysis.tex
@@ -59,7 +59,8 @@ coordinates are read from a \nwchem\ restart file by the directive,
 reference <string filename>
 \end{verbatim}
 
-where {\rm filename} is the name of an existing restart file.
+where {\rm filename} is the name of an existing restart file. This
+input is required.
 
 \section{Selection}
 
@@ -89,7 +90,8 @@ select 20 80 _N _CA _C
 
 \section{File specification}
 
-To specify the file to be analyzed
+To specify the file to be analyzed when the analysis module is
+invoked through a task directive
 
 \begin{verbatim}
 file [<integer firstfile> <integer lastfile>] <string filename>
@@ -127,6 +129,9 @@ rmsdev
 
 \section{Trajectory format conversion}
 
+The command in this section only apply when the analysis module is
+invoked though a task directive.
+\par
 To copy frames from specified files,
 
 \begin{verbatim}
@@ -173,13 +178,16 @@ from partial charges generated by the ESP module is generated
 by the command
 
 \begin{verbatim}
-espgrid [ spacing <real spac default 0.05> ] \\
+espgrid [ <integer chgset default 1> ] \\
+        [ spacing <real spac default 0.05> ] \\
         [ range <real rcut default 0.3> ]
 \end{verbatim}
 
 The input is taken from the charges file generated by the ESP module. The
 resulting plt formatted file can be graphically analyzed witht the
-gOpenMol program.
+gOpenMol program. The parameters chgset, spac and rcut specify the
+charge set to be used, and the spacing and extent of the charge grid
+evaluated.
 
 The name of the charges file can be specified with