1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
|
DOUBLE PRECISION FUNCTION DPMPAR(I)
INTEGER I
C **********
C
C FUNCTION DPMPAR
C
C THIS FUNCTION PROVIDES DOUBLE PRECISION MACHINE PARAMETERS
C WHEN THE APPROPRIATE SET OF DATA STATEMENTS IS ACTIVATED (BY
C REMOVING THE C FROM COLUMN 1) AND ALL OTHER DATA STATEMENTS ARE
C RENDERED INACTIVE. MOST OF THE PARAMETER VALUES WERE OBTAINED
C FROM THE CORRESPONDING BELL LABORATORIES PORT LIBRARY FUNCTION.
C
C THE FUNCTION STATEMENT IS
C
C DOUBLE PRECISION FUNCTION DPMPAR(I)
C
C WHERE
C
C I IS AN INTEGER INPUT VARIABLE SET TO 1, 2, OR 3 WHICH
C SELECTS THE DESIRED MACHINE PARAMETER. IF THE MACHINE HAS
C T BASE B DIGITS AND ITS SMALLEST AND LARGEST EXPONENTS ARE
C EMIN AND EMAX, RESPECTIVELY, THEN THESE PARAMETERS ARE
C
C DPMPAR(1) = B**(1 - T), THE MACHINE PRECISION,
C
C DPMPAR(2) = B**(EMIN - 1), THE SMALLEST MAGNITUDE,
C
C DPMPAR(3) = B**EMAX*(1 - B**(-T)), THE LARGEST MAGNITUDE.
C
C ARGONNE NATIONAL LABORATORY. MINPACK PROJECT. JUNE 1983.
C BURTON S. GARBOW, KENNETH E. HILLSTROM, JORGE J. MORE
C
C Modified Mon Aug 28 14:46:17 CDT 1989 by John W. Eaton
C (chpf127@emx.utexas.edu) to use D1MACH
C
C **********
C
DOUBLE PRECISION D1MACH
C
IF ( I .EQ. 1 ) THEN
DPMPAR = D1MACH(4)
ELSEIF ( I . EQ. 2 ) THEN
DPMPAR = D1MACH(1)
ELSEIF ( I .EQ. 3 ) THEN
DPMPAR = D1MACH(2)
ENDIF
C
RETURN
C
C LAST CARD OF FUNCTION DPMPAR.
C
END
|
