CodeLet

Set user password using RULES

This CodeLet allows to set the user password during Rule execution, the following process can be used.

a) create user entity ($newuser)
b) set a rules variable $password (use PHP code to generate a random string)
c) execute custom PHP which looks like

This way, you can also use the variable $password in say, an email to the user letting them know what their automatically generated password is.

Drupal: Programmatically manage members of sub groups

This CodeLet let you Programmatically manage members of sub groups. also you can add sub group.
you can inviter/remove peoples of sub groups. Invitation will be sent by email.
after installation of this CodeLet you must have to pass the group gid on query string,
Ex. yourdomain/subgroups/$gid.

CodeLet Dependencies:
1-Organic groups ( og )
2-Subgroups for Organic groups ( og_subgroups )
3-OG Invite People ( og_invite_people ).