fill with zeros

[claudio cortes]

Gretings:

I have the next matrix
date,month,day,hour,var1,var2,var3

ex:

2008,9,9,7,var1,var2,var3
2008,9,9,8,var1,var2,var3
2008,9,9,9,var1,var2,var3
2008,9,9,10,var1,var2,var3
2008,9,9,11,var1,var2,var3
.
.
.
2008,9,9,23,var1,var2,var3
2008,9,10,0,var1,var2,var3
2008,9,10,1,var1,var2,var3
2008,9,10,2,var1,var2,var3
2008,9,10,3,var1,var2,var3


And the question is... How can I standarize de output format of the
first four columns (year,month,day,hour) with two digits (09 instead
of 9,for example). Is there a fprintf option to do this ?

Thanks !

-- 
Claudio Cortes
+56 (2) 2994121

Meteorologo
Laboratorio de Meteorologia y Calidad de Aire
Centro Nacional del Medio Ambiente (CENMA)
--------------------------------------------------------------------------------------

Claudio Cortes
+56 (2) 2994121

Meteorologist
Meteorology and Air Quality Labs
National Enviroment Center, Chile (CENMA)