SLA_DR2TF - Radians to Hour,Min,Sec,Frac   

ACTION:

Convert an angle in radians to hours, minutes, seconds, fraction (double precision).

CALL:

CALL sla_DR2TF (NDP, ANGLE, SIGN, IHMSF)

GIVEN:

NDP number of decimal places of seconds

ANGLE D angle in radians

RETURNED:

SIGN `+' or `-'

IHMSF I(4) hours, minutes, seconds, fraction

NOTES:

1.

NDP less than zero is interpreted as zero.

2.

The largest useful value for NDP is determined by the size of ANGLE, the format of DOUBLE PRECISION floating-point numbers on the target machine, and the risk of overflowing IHMSF(4). For example, on a VAX computer, for ANGLE up to $2\pi$, the available floating-point precision corresponds roughly to NDP=12. However, the practical limit is NDP=9, set by the capacity of the 32-bit integer IHMSF(4).

3.

The absolute value of ANGLE may exceed $2\pi$. In cases where it does not, it is up to the caller to test for and handle the case where ANGLE is very nearly $2\pi$ and rounds up to 24 hours, by testing for IHMSF(1)=24 and setting IHMSF(1-4) to zero.