Struggling to write t0 from sometime ago

[Mphumzi Tshentu]

Would please help me, I tried to write t0 from 09h27min35sec in 17 February 2002. I want to get the time elapsed from that date up to a certain date later , for an example 13h22min40sec in 18 June 2004.

I tried writing in the following way and tried several other ways I don't seem to get it right.

octave-3.2.4.exe:1> t0=(clock(09:27:35),17-Feb-02

parse error:

 

  syntax error

octave-3.2.4.exe:1> t0=(clock(09:27:35) 17-Feb-02

Would you please help

Thanks

Mphumzi