angle2hms: Convert astronomical angle in degrees to hours, minutes and...

Description Usage Arguments Value Author(s) References See Also Examples

View source: R/astronomy.R

Description

The purpose of angle2hms is to facilitate comparison of rightAscension angles computed by sunAngle() and moonAngle() with angles reported in astronomical sources and software, which often employ an hour-minute-second notation. In that notation, decimal hour is computed as 24/360 times the angle in degrees, and from that decimal hour are compute integer hour and minute values, plus a decimal second value. It is common in the astronomical literature to use strings to represent the results, e.g. with 11h40m48s.10 for the value used in the “Examples”; see Chapter 1 of Meeus (1991) for more on angle calculation and representation.

Usage

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angle2hms(angle)

Arguments

angle

numerical value giving an angle in degrees

Value

angle2hms returns a list containing values time (a numerical value for decimal hour, between 0 and 24), hour, minute, and second (the last of which may have a fractional part), and string, a character value indicates the time in hour-minute-second notation, with the second part to two decimal places and intervening h, m and s characters between the units.

Author(s)

Dan Kelley

References

See Also

Other things related to astronomy: eclipticalToEquatorial(), equatorialToLocalHorizontal(), julianCenturyAnomaly(), julianDay(), moonAngle(), siderealTime(), sunAngle(), sunDeclinationRightAscension()

Examples

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# A randomly-chosen example on page 99 of Meeus (1991).
angle2hms(177.74208) # string component 11h50m58s.10

dankelley/oce documentation built on April 8, 2021, 3:47 a.m.