How to run an example script?

[Pang Kun <pk@atm.mdc.tsinghua.edu.cn>]

Hi,everybody,

I'm  a new user of Ns-2. Though I have installed ns-2 successfully, I
can't figure out how to start simulation.

I tried to run /Otcl/lib/test.tcl, but nothing happened. And I write a
same script as what Ns document tell to do.
But "command not found" when run this script.

The Ns tool can be invoked in a command line method. But it seems not
able to perform all the command even the same
one as NsDocument . For example,"set duplex-link $n0 $n2 5Mb 2ms
DropTail" result is
"wrong #args: should be "set varName ?newValue?"

Has anyone had this problem?  Any help will be appreciated .
Thanks.