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diff libcruft/slatec-fn/asinh.f @ 7789:82be108cc558

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First attempt at single precision tyeps * * * corrections to qrupdate single precision routines * * * prefer demotion to single over promotion to double * * * Add single precision support to log2 function * * * Trivial PROJECT file update * * * Cache optimized hermitian/transpose methods * * * Add tests for tranpose/hermitian and ChangeLog entry for new transpose code
author David Bateman <dbateman@free.fr>
date Sun, 27 Apr 2008 22:34:17 +0200
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libcruft/slatec-fn/asinh.f	Sun Apr 27 22:34:17 2008 +0200
@@ -0,0 +1,74 @@
+*DECK ASINH
+      FUNCTION ASINH (X)
+C***BEGIN PROLOGUE  ASINH
+C***PURPOSE  Compute the arc hyperbolic sine.
+C***LIBRARY   SLATEC (FNLIB)
+C***CATEGORY  C4C
+C***TYPE      SINGLE PRECISION (ASINH-S, DASINH-D, CASINH-C)
+C***KEYWORDS  ARC HYPERBOLIC SINE, ASINH, ELEMENTARY FUNCTIONS, FNLIB,
+C             INVERSE HYPERBOLIC SINE
+C***AUTHOR  Fullerton, W., (LANL)
+C***DESCRIPTION
+C
+C ASINH(X) computes the arc hyperbolic sine of X.
+C
+C Series for ASNH       on the interval  0.          to  1.00000D+00
+C                                        with weighted error   2.19E-17
+C                                         log weighted error  16.66
+C                               significant figures required  15.60
+C                                    decimal places required  17.31
+C
+C***REFERENCES  (NONE)
+C***ROUTINES CALLED  CSEVL, INITS, R1MACH
+C***REVISION HISTORY  (YYMMDD)
+C   770401  DATE WRITTEN
+C   890531  Changed all specific intrinsics to generic.  (WRB)
+C   890531  REVISION DATE from Version 3.2
+C   891214  Prologue converted to Version 4.0 format.  (BAB)
+C***END PROLOGUE  ASINH
+      DIMENSION ASNHCS(20)
+      LOGICAL FIRST
+      SAVE ALN2, ASNHCS, NTERMS, XMAX, SQEPS, FIRST
+      DATA ALN2 /0.6931471805 5994530942E0/
+      DATA ASNHCS( 1) /   -.1282003991 1738186E0 /
+      DATA ASNHCS( 2) /   -.0588117611 89951768E0 /
+      DATA ASNHCS( 3) /    .0047274654 32212481E0 /
+      DATA ASNHCS( 4) /   -.0004938363 16265361E0 /
+      DATA ASNHCS( 5) /    .0000585062 07058557E0 /
+      DATA ASNHCS( 6) /   -.0000074669 98328931E0 /
+      DATA ASNHCS( 7) /    .0000010011 69358355E0 /
+      DATA ASNHCS( 8) /   -.0000001390 35438587E0 /
+      DATA ASNHCS( 9) /    .0000000198 23169483E0 /
+      DATA ASNHCS(10) /   -.0000000028 84746841E0 /
+      DATA ASNHCS(11) /    .0000000004 26729654E0 /
+      DATA ASNHCS(12) /   -.0000000000 63976084E0 /
+      DATA ASNHCS(13) /    .0000000000 09699168E0 /
+      DATA ASNHCS(14) /   -.0000000000 01484427E0 /
+      DATA ASNHCS(15) /    .0000000000 00229037E0 /
+      DATA ASNHCS(16) /   -.0000000000 00035588E0 /
+      DATA ASNHCS(17) /    .0000000000 00005563E0 /
+      DATA ASNHCS(18) /   -.0000000000 00000874E0 /
+      DATA ASNHCS(19) /    .0000000000 00000138E0 /
+      DATA ASNHCS(20) /   -.0000000000 00000021E0 /
+      DATA FIRST /.TRUE./
+C***FIRST EXECUTABLE STATEMENT  ASINH
+      IF (FIRST) THEN
+         NTERMS = INITS (ASNHCS, 20, 0.1*R1MACH(3))
+         SQEPS = SQRT (R1MACH(3))
+         XMAX = 1.0/SQEPS
+      ENDIF
+      FIRST = .FALSE.
+C
+      Y = ABS(X)
+      IF (Y.GT.1.0) GO TO 20
+C
+      ASINH = X
+      IF (Y.GT.SQEPS) ASINH = X*(1.0 + CSEVL (2.*X*X-1., ASNHCS,NTERMS))
+      RETURN
+C
+ 20   IF (Y.LT.XMAX) ASINH = LOG (Y + SQRT(Y**2+1.))
+      IF (Y.GE.XMAX) ASINH = ALN2 + LOG(Y)
+      ASINH = SIGN (ASINH, X)
+C
+      RETURN
+      END