Initial commit

1 files changed, 120 insertions, 0 deletions

diff --git a/math/slalib/afin.f b/math/slalib/afin.f
new file mode 100644
index 00000000..7e7fac4f
--- /dev/null
+++ b/math/slalib/afin.f
@@ -0,0 +1,120 @@
+      SUBROUTINE slAFIN (STRING, IPTR, A, J)
+*+
+*     - - - - -
+*      A F I N
+*     - - - - -
+*
+*  Sexagesimal character string to angle (single precision)
+*
+*  Given:
+*     STRING  c*(*)   string containing deg, arcmin, arcsec fields
+*     IPTR      i     pointer to start of decode (1st = 1)
+*
+*  Returned:
+*     IPTR      i     advanced past the decoded angle
+*     A         r     angle in radians
+*     J         i     status:  0 = OK
+*                             +1 = default, A unchanged
+*                             -1 = bad degrees      )
+*                             -2 = bad arcminutes   )  (note 3)
+*                             -3 = bad arcseconds   )
+*
+*  Example:
+*
+*    argument    before                           after
+*
+*    STRING      '-57 17 44.806  12 34 56.7'      unchanged
+*    IPTR        1                                16 (points to 12...)
+*    A           ?                                -1.00000
+*    J           ?                                0
+*
+*    A further call to slAFIN, without adjustment of IPTR, will
+*    decode the second angle, 12deg 34min 56.7sec.
+*
+*  Notes:
+*
+*     1)  The first three "fields" in STRING are degrees, arcminutes,
+*         arcseconds, separated by spaces or commas.  The degrees field
+*         may be signed, but not the others.  The decoding is carried
+*         out by the DFLTIN routine and is free-format.
+*
+*     2)  Successive fields may be absent, defaulting to zero.  For
+*         zero status, the only combinations allowed are degrees alone,
+*         degrees and arcminutes, and all three fields present.  If all
+*         three fields are omitted, a status of +1 is returned and A is
+*         unchanged.  In all other cases A is changed.
+*
+*     3)  Range checking:
+*
+*           The degrees field is not range checked.  However, it is
+*           expected to be integral unless the other two fields are
+*           absent.
+*
+*           The arcminutes field is expected to be 0-59, and integral if
+*           the arcseconds field is present.  If the arcseconds field
+*           is absent, the arcminutes is expected to be 0-59.9999...
+*
+*           The arcseconds field is expected to be 0-59.9999...
+*
+*     4)  Decoding continues even when a check has failed.  Under these
+*         circumstances the field takes the supplied value, defaulting
+*         to zero, and the result A is computed and returned.
+*
+*     5)  Further fields after the three expected ones are not treated
+*         as an error.  The pointer IPTR is left in the correct state
+*         for further decoding with the present routine or with DFLTIN
+*         etc.  See the example, above.
+*
+*     6)  If STRING contains hours, minutes, seconds instead of degrees
+*         etc, or if the required units are turns (or days) instead of
+*         radians, the result A should be multiplied as follows:
+*
+*           for        to obtain    multiply
+*           STRING     A in         A by
+*
+*           d ' "      radians      1       =  1.0
+*           d ' "      turns        1/2pi   =  0.1591549430918953358
+*           h m s      radians      15      =  15.0
+*           h m s      days         15/2pi  =  2.3873241463784300365
+*
+*  Called:  slDAFN
+*
+*  P.T.Wallace   Starlink   13 September 1990
+*
+*  Copyright (C) 1995 Rutherford Appleton Laboratory
+*
+*  License:
+*    This program is free software; you can redistribute it and/or modify
+*    it under the terms of the GNU General Public License as published by
+*    the Free Software Foundation; either version 2 of the License, or
+*    (at your option) any later version.
+*
+*    This program is distributed in the hope that it will be useful,
+*    but WITHOUT ANY WARRANTY; without even the implied warranty of
+*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*    GNU General Public License for more details.
+*
+*    You should have received a copy of the GNU General Public License
+*    along with this program (see SLA_CONDITIONS); if not, write to the
+*    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+*    Boston, MA  02110-1301  USA
+*
+*  Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.
+*-
+
+      IMPLICIT NONE
+
+      CHARACTER*(*) STRING
+      INTEGER IPTR
+      REAL A
+      INTEGER J
+
+      DOUBLE PRECISION AD
+
+
+
+*  Call the double precision version
+      CALL slDAFN(STRING,IPTR,AD,J)
+      IF (J.LE.0) A=REAL(AD)
+
+      END