Introduction to Stata 8 - (GRIPS

y and bysort prefix [U] 14.5
Makes a command display results for subgroups of the data. Data must be pre-sorted:
sort sex
by sex: summarize age height weight
or, in one line:
bysort sex: summarize age height weight
Text strings, quotes
Stata requires double quotes around text strings, but you may omit quotes unless the string has
embedded blanks or commas:
label define sex 1 male 2 female 9 "sex unknown"
You need not use quotes around filenames:
save c:\dokumenter\proj1\alfa1.dta
unless they include blank space:
save "c:\dokumenter\project 1\alfa1.dta"
Comments [U] 19.1.2
The following is interpreted as comments, to include short explanations in a do-file:
• Lines that begin with *
• text surrounded by /* and */
• Text following // (the easy way; used in this booklet)
The purpose of comments is to make do-files more readable to yourself – Stata does not care
whatever you write.
// C:\DOKUMENTER\PROFILE.DO executes when opening Stata
summarize bmi , detail // Body mass index
Long command lines [U] 19.1.3
By default a command ends when the line ends (carriage return), and no special delimiter
terminates commands. However, command lines in do- and ado-files should be no longer than
80 characters. The problem is solved by /// signalling that the following line is a
continuation.
infix str10 cprstr 1-10 bday 1-2 bmon 3-4 byear 5-6 ///
control 7-10 using c:\dokumenter\p1\datefile.txt
Another option is to define ; (semicolon) as the future command delimiter:
#delimit ; // Semicolon delimits future commands
infix str10 cprstr 1-10 bday 1-2 bmon 3-4 byear 5-6
control 7-10 using c:\dokumenter\p1\datefile.txt ;
tab1 opagr ;
#delimit cr // Back to normal: Carriage return delimiter
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