changing load at each bus

[deepak.....]

Sir
I want to change load at each bus for simulating different scenario of
load.

For changing load at a bus we write ;

mpc.bus(bus_no,PD)=value.

For a 30 bus system I want to change PD at all 30 buses . How to do so by
writing code
mpc.bus(:,PD)=new values , will work ?