[R] Sum by categorical variable

[De Amicis Fabrizio (G.I.T.)]

Dear R-list,
I have two variables (numerical and categorical) and  would like to have the
sum (and maybe some other statistics) of the numerical variable by the
categorical one. 
Can you help me,
Thank you,
Fabrizio


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Fabrizio De Amicis

IT Department
Generali Information Technologies - (GIT)

Centro Galleria 2,
Via Cantonale
CH - 6928 Manno - Switzerland
Tel  +41 91 806 6220
Fax +41 91 806 6298
E-mail: fabrizio.deamicis at git.generali.ch  




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