*Stata programming by Example
*Tutorial 3



**Example 1, loops

*--------------Start Example  1 ----------------*

sysuse auto, clear
forvalues i=1/10 {
display as text "`i'"
}

*--------------End Example----------------------*



*--------------Start Example  2 ----------------*

sysuse auto, clear
forvalues i=0 (2) 10 {
display as text "`i'"
}

*--------------End Example----------------------*



*--------------Start Example  3 ----------------*

sysuse auto, clear
forvalues i=2 (2) 10 {
list mpg in `i'
}

*--------------End Example----------------------*



* Using the trace command to see what is being substituted
*--------------Start Example  4 ----------------*

sysuse auto, clear
set trace on
forvalues i=2 (2) 10 {
list mpg in `i'
}
set trace off
*--------------End Example----------------------*
help trace



*--------------Start Example  5 ----------------*

sysuse auto, clear
set more off
summarize mpg
forvalues i=1/`=_N'  {
list mpg in `i'
}

*--------------End Example----------------------*
* for more details in `=_N' see Stata 10 user guide 18.3.8



*--------------Start Example  6 ----------------*

sysuse auto, clear
foreach i in 1 2 3 4 {
list mpg in `i'
}

*--------------End Example----------------------*


*--------------Start Example  7 ----------------*

sysuse auto, clear
foreach i of varlist mpg price {
histogram `i'
sleep 1000
}

*--------------End Example----------------------*
help sleep


*--------------Start Example  8 ----------------*

local a 2 
foreach i of local a   {
display "`i'"
}

*--------------End Example----------------------*


*--------------Start Example  9 ----------------*

local a " one two three" 
foreach i of local a   {
 display "`i'"
}

*--------------End Example----------------------*
help foreach
*see further examples on the Stata online help page for this command 




*--------------Start Example  10 ----------------*

local i=0   //starting value of i

while `i' < 10   {
local ++i    //increments i by 1 , more on incrementing later
display "`i'"
}

*--------------End Example----------------------*
help while




*--------------Start Example  11 ----------------*

local i=0   //starting value of i

while `i' < 10   {
 local ++i    //increments i by 1 , more on incrementing later
display "`i'"
continue, break
}

*--------------End Example----------------------*
help continue





*End tutorial 3 - programming Stata