Dataplot Vol 2 Vol 1

# CHEBYSHEV DISTANCE

Name:
CHEBYSHEV DISTANCE (LET)
Type:
Let Subcommand
Purpose:
Compute the Chebyshev distance between two variables.
Description:
The Chebyshev distance between two variabes X and Y is defined as

$d = \max_{i} {|X_{i} - Y_{i}|}$
Syntax:
LET <par> = CHEBYSHEV DISTANCE <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 Chebyshev distance is stored;
and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
LET A = CHEBYSHEV DISTANCE Y1 Y2
LET A = CHEBYSHEV DISTANCE Y1 Y2 SUBSET Y1 > 0 SUBSET Y2 > 0
Note:
Dataplot statistics can be used in a number of commands. For details, enter

Default:
None
Synonyms:
None
Related Commands:
 COSINE DISTANCE = Compute the cosine distance. MANHATTAN DISTANCE = Compute the Euclidean distance. EUCLIDEAN DISTANCE = Compute the Euclidean distance. MATRIX DISTANCE = Compute various distance metrics for a matrix. GENERATE MATRIX = Compute a matrix of pairwise statistic values.
Applications:
Mathematics
Implementation Date:
2017/08
Program 1:

SKIP 25
READ IRIS.DAT Y1 TO Y4 X
.
LET DIST  = CHEBYSHEV DISTANCE Y1 Y2
SET WRITE DECIMALS 4
TABULATE CHEBYSHEV DISTANCE Y1 Y2 X

Cross Tabulate CHEBYSHEV DISTANCE

(Response Variables: Y1       Y2      )
---------------------------------------------
X          |   CHEBYSHEV DISTA
---------------------------------------------
1.0000   |            2.2000
2.0000   |            4.0000
3.0000   |            5.1000

.
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
.
TITLE Chebyshev Distance (IRIS.DAT)
Y1LABEL Chebyshev Distance
CHEBYSHEV DISTANCE PLOT Y1 Y2 X


Program 2:

set write decimals 3
dimension 100 columns
.
skip 25
read iris.dat y1 y2 y3 y4
skip 0
.
let z = generate matrix chebyshev distance y1 y2 y3 y4
print z

The following output is generated
        MATRIX Z       --            4 ROWS
--            4 COLUMNS

VARIABLES--Z1             Z2             Z3             Z4

0.000          5.100          5.600          6.600
5.100          0.000          4.300          4.000
5.600          4.300          0.000          4.700
6.600          4.000          4.700          0.000


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

Date created: 08/31/2017
Last updated: 08/31/2017