Command Reference : Matrix Language Reference
  
 
@inner
Syntax: @inner(v1, v2, smp)
Argument 1: vector, rowvector, or series, v1
Argument 2: vector, rowvector, or series, v2
Argument 3: (optional) sample, smp
Return: scalar
 
Syntax: @inner(o, smp)
Argument 1: matrix object or group, o
Argument 2: (optional) sample, smp
Return: sym
If used with two vectors, v1 and v2, @inner returns the dot or inner product of the two vectors. Examples:
scalar sc1 = @inner(v1, v2)
s1(1,2) = @inner(v1, r1)
If used with two series, @inner returns the inner product of the series using observations in the workfile sample. You may provide an optional sample.
If used with a matrix or sym, o, @inner returns the inner product, or moment matrix, oo. Each element of the result is the vector inner product of two columns of the source matrix. The size of the resulting sym is the number of columns in o. Examples:
scalar sc1 = @inner(v1)
sym sym1 = @inner(m1)
If used with a group, @inner returns the uncentered second moment matrix of the data in the group, g, using the observations in the sample, smp. If no sample is provided, the workfile sample is used. Examples:
sym s2 = @inner(gr1)
sym s3 = @inner(gr1, smp1)
See also @outer.