Linear<T> is a Kernel. Specifically, it is a Mercer Kernel. When using a linear kernel, input space
is identical to feature space
. If k is an object of class linear<T>, and u and v are objects of class T, then k(u,v) returns the inner product

which is defined to be the product if T is a scalar type.
vector< double > u(10); vector< double > v(10); linear< vector< double > > kernel; cout << kernel( u, v ) << endl;
Defined in the KML header <kml/linear.hpp>.
| Parameter | Description | Default |
| T | The linear argument type | |
Mercer Kernel, Default Constructible, Copy Constructible
T must be a vector type or a numeric type; distance_squared<T> should evaluate.
| Member | Where defined | Description |
| linear() | Default Constructible | The default constructor |
| result_type | Input value | The type of the result: input_value<T> |