(* realconst.mod basic floating point test.

Copyright (C) 2001-2019 Free Software Foundation, Inc.
Contributed by Gaius Mulley <gaius.mulley@southwales.ac.uk>.

This file is part of GNU Modula-2.

GNU Modula-2 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 3, or (at your option)
any later version.

GNU Modula-2 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 GNU Modula-2; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  *)

MODULE realconst ;

FROM StrIO IMPORT WriteString, WriteLn ;
FROM MathLib0 IMPORT pi ;
FROM FpuIO IMPORT WriteReal, ReadReal ;

VAR
   Degrees, Radians: REAL ;


PROCEDURE ConvertAngle (angle:REAL): REAL ;
VAR
   ConversionFactor: REAL ;
BEGIN
   ConversionFactor:= pi / 180.0 ;
   WriteString ('Conversion factor ') ;
   WriteReal (ConversionFactor, 20, 15 ) ;
   WriteLn ;
   RETURN ConversionFactor * angle
END ConvertAngle;

BEGIN
   WriteString ("Enter an angle in degrees:  ") ;
   ReadReal (Degrees) ; WriteLn ;
   Radians := ConvertAngle (Degrees) ;
   WriteString ("The angle in radians is:  ") ;
   WriteReal (Radians, 20, 5) ; WriteLn ;
END realconst.