Dear,
It seems there's a problem with the decimal point in gretl's french version.
Let's try for example with the script below:
 
<hansl>
nulldata 100
series x = normal()
series y =normal()
discrete y
summary x --by=y
<\hansl>
 
Gretl ends up with a message error:
x == -2,
The symbol ',' is not valid in this context
Syntax error
 
Best,
Artur
 

Artur Bala
economist, consultant
 
phone:   (216) 22 99 73 44
skype:   artur.bala.tn