st: Collapsing and Reshaping

["Katie and Matt O'Varanese" <ovaranese@gmail.com>]

I am trying to reshape some data long... right now the data looks like
this for example:

id_code     year       math06   math07  math08    eng06    eng07    eng08

112           2006
112           2007
112              .
112              .
113           2006
113           2007
113              .
113           2008
114              .
114           2007
114           2008

When I try:  reshape long [vars@x], i(id_code) j(year)
i get an error message "i=id_code does not uniquely identify the observations;
there are multiple observations with the same value of id_code."
Do I need to collapse first?  If so, when I try to collapse by
(id_code year), I get an error message saying that the year variable
has missing values.

Do I need to change the missing values to a numeric dummy just to
complete the command?  or is there a better way to do this?  Ultimate
goal: I want to have unique id_code and then a year variable with each
of the three years represented (06, 07, 08).


Help please!  Thanks as always!!

Kate
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/