units.h

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/* Copyright (C) 2004-2017 Chris Piker <chris-piker@uiowa.edu>
 *                         Jeremy Faden <jeremy-faden@uiowa.edu> 
 *
 * This file is part of libdas2, the Core Das2 C Library.
 * 
 * Libdas2 is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License version 2.1 as published
 * by the Free Software Foundation.
 *
 * Libdas2 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 Lesser General Public License for
 * more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * version 2.1 along with libdas2; if not, see <http://www.gnu.org/licenses/>. 
 */
 
 
#ifndef _das_units_h_
#define _das_units_h_
 
#include <stdbool.h>
#include <das2/time.h>
 
#ifdef __cplusplus
extern "C" {
#endif
 
bool units_init(const char* sProgName);
 
#ifndef _das_units_c_
 
extern const char* UNIT_US2000; /* microseconds since midnight, Jan 1, 2000 */
extern const char* UNIT_MJ1958; /* days since midnight, Jan 1, 1958 */
extern const char* UNIT_T2000;  /* seconds since midnight, Jan 1, 2000 */
extern const char* UNIT_T1970;  /* seconds since midnight, Jan 1, 1970 */
extern const char* UNIT_NS1970; /* nanoseconds since midnight, Jan 1, 1970 */
extern const char* UNIT_UTC;    /* Time strings on the Gregorian Calendar */
 
/* nanoseconds since 2000-01-01T11:58:55.816, the only leap-second aware time
   unit in the library.  Uses the CDF_LEAPSECONDSTABLE environment variable
   to find new leap seconds.  Not needed if library has been build since
   last know leapsecond in the data time. */
extern const char* UNIT_TT2000; 
 
/* Other common units */
extern const char* UNIT_SECONDS;
extern const char* UNIT_HOURS;
extern const char* UNIT_DAYS;
extern const char* UNIT_MILLISECONDS;
extern const char* UNIT_MICROSECONDS;
extern const char* UNIT_NANOSECONDS;
 
extern const char* UNIT_HERTZ;
extern const char* UNIT_KILO_HERTZ;
extern const char* UNIT_MEGA_HERTZ;
extern const char* UNIT_E_SPECDENS;
extern const char* UNIT_B_SPECDENS;
extern const char* UNIT_NT;
 
extern const char* UNIT_NUMBER_DENS;
      
extern const char* UNIT_DB;
 
extern const char* UNIT_KM;
 
extern const char* UNIT_EV;
 
extern const char* UNIT_DEGREES;
extern const char* UNIT_DIMENSIONLESS;
 
/* color:  Color should be handled as as vector, we don't have
 * support for vectors at this time.   Also a datatype of 
 * byte is needed for small values
 */
/* extern const char* UNIT_RGB; */
 
 
#endif
 
typedef const char* das_units;
 
DAS_API das_units Units_fromStr(const char* string);
 
 
DAS_API const char* Units_toStr(das_units unit);
 
 
DAS_API char* Units_toLabel(das_units unit, char* sBuf, int nLen);
 
 
DAS_API das_units Units_invert(das_units unit);
 
 
DAS_API das_units Units_multiply(das_units ut1, das_units ut2);
 
DAS_API das_units Units_divide(das_units a, das_units b);
 
 
DAS_API das_units Units_power(das_units unit, int power);
 
 
DAS_API das_units Units_root(das_units unit, int root );
 
 
DAS_API das_units Units_interval(das_units unit);
 
 
DAS_API das_units Units_reduce(das_units orig, double* pFactor);
 
DAS_API bool Units_canConvert(das_units fromUnits , das_units toUnits);
 
 
DAS_API double Units_convertTo( das_units toUnits, double rVal, das_units fromUnits );
 
 
DAS_API bool Units_haveCalRep(das_units unit);
 
 
DAS_API void Units_convertToDt(das_time* pDt, double value, das_units epoch_units);
 
DAS_API double Units_convertFromDt(das_units epoch_units, const das_time* pDt);
 
DAS_API double Units_secondsSinceMidnight( double rVal, das_units epoch_units );
 
 
/* Get the Julian day for the Datum (double,unit) */
DAS_API int Units_getJulianDay( double timeDouble, das_units epoch_units );
 
DAS_API bool Units_canMerge(das_units left, int op, das_units right);
 
#ifdef __cplusplus
}
#endif
 
#endif /* _das_units_h_ */