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INTEGER FUNCTION I1MACH(I)
C Integer machine dependent constants
C I/O unit numbers.
C I1MACH( 1) = the standard input unit.
C I1MACH( 2) = the standard output unit.
C I1MACH( 3) = the standard punch unit.
C I1MACH( 4) = the standard error message unit.
C
C Words.
C I1MACH( 5) = the number of bits per integer storage unit.
C I1MACH( 6) = the number of characters per integer storage unit.
C
C Integers.
C assume integers are represented in the S-digit, base-A form
C
C sign ( X(S-1)*A**(S-1) + ... + X(1)*A + X(0) )
C
C where 0 .LE. X(I) .LT. A for I=0,...,S-1.
C I1MACH( 7) = A, the base.
C I1MACH( 8) = S, the number of base-A digits.
C I1MACH( 9) = A**S - 1, the largest magnitude.
C
C Floating-Point Numbers.
C Assume floating-point numbers are represented in the T-digit,
C base-B form
C sign (B**E)*( (X(1)/B) + ... + (X(T)/B**T) )
C
C where 0 .LE. X(I) .LT. B for I=1,...,T,
C 0 .LT. X(1), and EMIN .LE. E .LE. EMAX.
C I1MACH(10) = B, the base.
C
C Single-Precision
C I1MACH(11) = T, the number of base-B digits.
C I1MACH(12) = EMIN, the smallest exponent E.
C I1MACH(13) = EMAX, the largest exponent E.
C
C Double-Precision
C I1MACH(14) = T, the number of base-B digits.
C I1MACH(15) = EMIN, the smallest exponent E.
C I1MACH(16) = EMAX, the largest exponent E.
C
C Reference: Fox P.A., Hall A.D., Schryer N.L.,"Framework for a
C Portable Library", ACM Transactions on Mathematical
C Software, Vol. 4, no. 2, June 1978, PP. 177-188.
C
REAL*8 DLAMCH
INTEGER IMACH(16)
DATA IMACH/ 5,6,0,6,32,4,2,31,2147483647,2,0,0,0,0,0,0 /
C
C Get double precision values from DLAMCH
IF (IMACH(16) .EQ. 0) THEN
IMACH(14) = DLAMCH('N')
IMACH(15) = DLAMCH('M')
IMACH(16) = DLAMCH('L')
ENDIF
C
I1MACH=IMACH(I)
RETURN
END
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