# Displaying the meaning of an operator using Information

I'm using CircleTimes ($\otimes$) operator defined as

a_\[CircleTimes]b_ := KroneckerProduct[a, b]


so I can use a ESC c* ESC b to write $a\otimes b$ instead of KroneckerProduct[a, b]. What should I do in order to find out the definition of the $\otimes$ symbol using Information function or assign a usage to this symbol?

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From the documentation:

Mathematica follows the general convention that the function associated with a particular operator should have the same name as the special character that represents that operator.

Therefore the Symbol associated with the character \[CircleTimes] is simply CircleTimes.

a_\[CircleTimes]b_ := KroneckerProduct[a, b]

Definition[CircleTimes]

a_\[CircleTimes]b_ := KroneckerProduct[a, b]


You can select the operator and press F1 to bring up the documentation page, e.g. CircleTimes.

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Thanks. So I guess that it is better to define this operator as CircleTimes[x_,y_] := KroneckerProduct[x,y]; – Jarek Miszczak Aug 29 '13 at 10:51
@Jarek No, your original definition is perfectly acceptable. What did you infer that made you think otherwise? – Mr.Wizard Aug 29 '13 at 10:54
I know that the first one work fine, but I think it is more consistent if I use the second, since I can add usage to CircleTimes but not to $\otimes$ (CircleTimes::usage ="" is OK, but $\otimes$::usage not). Besides using $\otimes$ in a package is problematic. – Jarek Miszczak Aug 29 '13 at 11:27
@Jarek As you see fit. Since I appreciate brevity I would use the operator form where it works, and the long form where it doesn't. At least you now know what you're working with. – Mr.Wizard Aug 29 '13 at 11:28