a2tf¶
- erfa.a2tf(ndp, angle)[source]¶
Decompose radians into hours, minutes, seconds, fraction.
- Parameters:
- ndpint array
- angledouble array
- Returns:
- signchar array
- ihmsfint array
Notes
Wraps ERFA function
eraA2tf
. The ERFA documentation is:- - - - - - - - e r a A 2 t f - - - - - - - - Decompose radians into hours, minutes, seconds, fraction. Given: ndp int resolution (Note 1) angle double angle in radians Returned: sign char '+' or '-' ihmsf int[4] hours, minutes, seconds, fraction Notes: 1) The argument ndp is interpreted as follows: ndp resolution : ...0000 00 00 -7 1000 00 00 -6 100 00 00 -5 10 00 00 -4 1 00 00 -3 0 10 00 -2 0 01 00 -1 0 00 10 0 0 00 01 1 0 00 00.1 2 0 00 00.01 3 0 00 00.001 : 0 00 00.000... 2) The largest positive useful value for ndp is determined by the size of angle, the format of doubles on the target platform, and the risk of overflowing ihmsf[3]. On a typical platform, for angle up to 2pi, the available floating-point precision might correspond to ndp=12. However, the practical limit is typically ndp=9, set by the capacity of a 32-bit int, or ndp=4 if int is only 16 bits. 3) The absolute value of angle may exceed 2pi. In cases where it does not, it is up to the caller to test for and handle the case where angle is very nearly 2pi and rounds up to 24 hours, by testing for ihmsf[0]=24 and setting ihmsf[0-3] to zero. Called: eraD2tf decompose days to hms This revision: 2021 May 11 Copyright (C) 2013-2023, NumFOCUS Foundation. Derived, with permission, from the SOFA library. See notes at end of file.