All cross-products and squares - ------------------------------
^allcross^ varlist
Description - -----------
^allcross^ creates variables corresponding to the cross-products and squares of the variables in varlist. The names of the created variables are formed by concatenating the names in varlist involved in the cross-product term. Since variable names are limited to 8 characters an error occurs if varlist contains variables with names longer than 4 characters.
Examples - --------
. ^allcross x1 x2 x3^ . ^allcross x1-x4 age y1-y3^
Note - ----
The user should be aware that when ^allcross^ is given a large number of variables in the varlist that it will end up creating a very large number of variables in the user's working data set. For example, if the user has 30 variables in her data set and executes ^allcross _all^, she will then have 30+(30*31)/2 = 495 variables in her data set.
Author - ------
Kenneth Higbee Stata Corp. khigbee@@stata.com