SED navigation bar go to SED home page go to Dataplot home page go to NIST home page SED Home Page SED Staff SED Projects SED Products and Publications Search SED Pages
Dataplot Vol 2 Vol 1

DOT PRODUCT

Name:
    DOT PRODUCT (LET)
Type:
    Let Subcommand
Purpose:
    Compute the dot product between two variables.
Description:
    The dot product between two variabes X and Y is the sum of the products. The formula for the dot product is

      \( X \cdot Y = \sum_{i=1}^{n}{X_{i} Y_{i}} \)
Syntax:
    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.
Examples:
    LET A = DOT PRODUCT Y1 Y2
    LET A = DOT PRODUCT Y1 Y2 SUBSET Y1 > 0 SUBSET Y2 > 0
Note:
    Dataplot statistics can be used in a number of commands. For details, enter

    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.

Default:
    None
Synonyms:
    None
Related Commands: Applications:
    Mathematics
Implementation Date:
    2017/03
Program:
     
    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
        
    plot generated by sample program

Privacy Policy/Security Notice
Disclaimer | FOIA

NIST is an agency of the U.S. Commerce Department.

Date created: 07/10/2017
Last updated: 07/10/2017

Please email comments on this WWW page to alan.heckert@nist.gov.