Re: st: Conditional infile statements,

[Gordon Hughes <G.A.Hughes@ed.ac.uk>]

I would like to thank those who responded to my original posting with 
suggestions for reading data with multiple line formats.  My slowness 
in replying does not reflect lack of appreciation but the exigencies 
of other business.

I have experimented with the various suggestions and have eventually 
returned to the option reading each line into a string variable and 
extracting the variables of interest from the string via sub-string 
operations.  I described this as "clumsy", though "inelegant" might 
have been a better word.  On the other hand, I found that a brute 
force approach gave me a better understanding what I was doing so 
that it was easier to correct mistakes.  Further, this method is 
pretty much what Stata would do if it permitted conditional infile 
statements - though processing the dataset line by line rather 
reading the full dataset and then processing each line.  The one 
disadvantage is that the initial read step may require a lot of 
memory if the maximum line length is large (my data has ~50 million 
records), so I had to break up the data into manageable chunks.

Finally, may I offer best wishes for a happy Thanksgiving holiday to 
both StataCorp and other readers in the US.

Gordon Hughes
g.a.hughes@ed.ac.uk   

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