isnumeric
isnumeric(X) returns true if X is of type double.
Examples
> isnumeric('a')
[ans:false]
> isnumeric(1) [ans:true]
> isnumeric(1+i) [ans:true]
Resources
> isnumeric('a')
[ans:false]
> isnumeric(1) [ans:true]
> isnumeric(1+i) [ans:true]