--- loncom/html/adm/help/tex/Problem_LON-CAPA_Functions.tex	2013/07/10 16:00:52	1.24
+++ loncom/html/adm/help/tex/Problem_LON-CAPA_Functions.tex	2014/06/12 14:44:27	1.28
@@ -141,7 +141,7 @@ Option 1 - \&map(\$seed,[$\backslash$\$w
 epoch (UTC), which can be used in calculations.\\
 \hline
 
-\&submission(\$partid,\$responseid,\$version) & Returns what the student submitted for response \$responseid in part \$partid. You can get these IDs from the XML-code of the problem. \$version is optional and returns the \$version-th submission of the student that was graded.\\
+\&submission(\$partid,\$responseid,\$version) & Returns what the student submitted for response \$responseid in part \$partid. You can get these IDs from the XML-code of the problem. Use 0 as \$partid for problems without parts. \$version is optional and returns the \$version-th submission of the student that was graded. If \$version is 0 or ommitted, the latest submission is returned.\\
 \hline
 
 \&parameter\_setting(\$name,\$partid) & Returns the parameter setting \$name. Partid is optional.\\
@@ -240,3 +240,13 @@ undef @name  & To destroy the contents o
  NOTE: \$ne is rounded using int() and the result must be positive. \$p must be between 0 and 1 exclusive.  & Generate an array of \$item\_cnt outcomes generated from negative binomial distribution with \$ne events and the probabilty of an event in each trial is \$p.  \\
 \hline
 \end{longtable}
+
+The \&EXT() \index{\&EXT}external function is extremely powerful, and is used to access parameters 
+and submission values.  It can be
+used within scripts and also within cell formulas in the grading spreadsheet.
+Some examples can be found by browsing in the repository to /res/msu/albertel/test/ext\_examples.html.
+The \&EXT() function can be used to obtain values for the same parameters as are retrived by some of the other (newer) helper functions  
+summarized in the table above, such as \&firstname() which is equivalent to \&EXT(`environment.firstname'),
+and \&parameter\_setting(\$name,\$partid) is equivalent to \&EXT(`resource.'.\$partid.`.'.\$name).
+In such cases the newer (specialized) functions are preferred to \&EXT() on the basis of ease of use.
+