DOT PRODUCT

DOT PRODUCT (LET)

Let Subcommand

Compute the dot product between two variables.

The dot product between two variabes X and Y is the sum of the products. The formula for the dot product is
\( X \cdot Y = \sum_{i=1}^{n}{X_{i} Y_{i}} \)

LET <par> = DOT PRODUCT <y1> <y2>
                        <SUBSET/EXCEPT/FOR qualification>
where <y1> is the first response variable;
            <y2> is the second response variable;
            <par> is a parameter where the computed dot product is stored;
and where the <SUBSET/EXCEPT/FOR qualification> is optional.

LET A = DOT PRODUCT Y1 Y2
LET A = DOT PRODUCT Y1 Y2 SUBSET Y1 > 0 SUBSET Y2 > 0

Dataplot statistics can be used in a number of commands. For details, enter
HELP STATISTICS

This command performs the same function as the VECTOR DOT PRODUCT. The distinction is that DOT PRODUCT is implemented as a Statistics LET subcommand while VECTOR DOT PRODUCT is implemented as a Mathematics LET subcommand. The Statistics LET subcommands work with the commands documented in HELP STATISTICS while the Mathematics LET subcommands do not.

None

None

EUCLIDEAN DISTANCE	=	Compute the Euclidean distance.
EUCLIDEAN LENGTH	=	Compute the Euclidean length.
COSINE DISTANCE	=	Compute the cosine distance.
MANHATTAN DISTANCE	=	Compute the Manhattan distance.
MATRIX DISTANCE	=	Compute various distance metrics for a matrix.

Mathematics

2017/03

 
SKIP 25
READ IRIS.DAT Y1 TO Y4 X
.
LET DDOT  = DOT PRODUCT Y1 Y2
SET WRITE DECIMALS 4
TABULATE DOT PRODUCT Y1 Y2 X
.
XTIC OFFSET 0.2 0.2
X1LABEL GROUP ID
LET NDIST = UNIQUE X
XLIMITS 1 NDIST
MAJOR X1TIC MARK NUMBER NDIST
MINOR X1TIC MARK NUMBER 0
CHAR X
LINE BLANK
LABEL CASE ASIS
CASE ASIS
TITLE CASE ASIS
TITLE OFFSET 2
.
SET STATISTIC PLOT REFERENCE LINE AVERAGE
TITLE Dot Product (IRIS.DAT)
Y1LABEL Dot Product
DOT PRODUCT PLOT Y1 Y2 X
    

The following output is generated

            Cross Tabulate DOT PRODUCT
 
(Response Variables: Y1       Y2      )
---------------------------------------------
       X          |   EUCLIDEAN DOT P
---------------------------------------------
         1.0000   |          862.8900
         2.0000   |          826.3100
         3.0000   |          984.2300