TimeDeltaQuantityString#

class astropy.time.TimeDeltaQuantityString(val1, val2, scale, precision, in_subfmt, out_subfmt, from_jd=False)[source]#

Bases: TimeDeltaFormat, TimeUnique

Time delta as a string with one or more Quantity components.

This format provides a human-readable multi-scale string representation of a time delta. It is convenient for applications like a configuration file or a command line option.

The format is specified as follows:

The string is a sequence of one or more components.
Each component is a number followed by an astropy unit of time.
For input, whitespace within the string is allowed but optional.
For output, there is a single space between components.
The allowed components are listed below.
The order (yr, d, hr, min, s) is fixed but individual components are optional.

The allowed input component units are shown below:

“yr”: years (365.25 days)
“d”: days (24 hours)
“hr”: hours (60 minutes)
“min”: minutes (60 seconds)
“s”: seconds

Note

These definitions correspond to physical units of time and are NOT calendar date intervals. Thus adding “1yr” to “2000-01-01 00:00:00” will give “2000-12-31 06:00:00” instead of “2001-01-01 00:00:00”.

The out_subfmt attribute specifies the components to be included in the string output. The default is "multi" which represents the time delta as "<days>d <hours>hr <minutes>min <seconds>s", where only non-zero components are included.

“multi”: multiple components, e.g. “2d 3hr 15min 5.6s”
“yr”: years
“d”: days
“hr”: hours
“min”: minutes
“s”: seconds

Examples

>>> from astropy.time import Time, TimeDelta
>>> import astropy.units as u

>>> print(TimeDelta("1yr"))
365d 6hr

>>> print(Time("2000-01-01") + TimeDelta("1yr"))
2000-12-31 06:00:00.000
>>> print(TimeDelta("+3.6d"))
3d 14hr 24min
>>> print(TimeDelta("-3.6d"))
-3d 14hr 24min
>>> print(TimeDelta("1yr 3.6d", out_subfmt="d"))
368.85d

>>> td = TimeDelta(40 * u.hr)
>>> print(td.to_value(format="quantity_str"))
1d 16hr
>>> print(td.to_value(format="quantity_str", subfmt="d"))
1.667d
>>> td.precision = 9
>>> print(td.to_value(format="quantity_str", subfmt="d"))
1.666666667d

Attributes Summary

`in_subfmt`
`jd1`
`jd2`
`name`
`out_subfmt`
`precision`
`re_float`
`re_ydhms`
`scale`	Time scale.
`subfmts`
`value`

Methods Summary

`fill_value`(subfmt)	Return a value corresponding to J2000 (2000-01-01 12:00:00) in this format.
`fix_comp_vals_overflow`(comp_vals)
`get_multi_comps`(jd1, jd2)
`parse_string`(timestr)	Read time from a single string
`set_jds`(val1, val2)	Parse the time strings contained in val1 and get jd1, jd2.
`to_value`([parent, out_subfmt])	Return time representation from internal jd1 and jd2 in specified `out_subfmt`.

Attributes Documentation

in_subfmt#

jd1#

jd2#

name = 'quantity_str'#

out_subfmt#

precision#

re_float = '(\\d+(\\.\\d*)?|\\.\\d+)([eE][-+]?\\d+)?'#

re_ydhms = re.compile('^ \\s*\n (?P<sign>[-+])? \\s* # Optional sign\n (?=[^-+\\s]) # At least one character which is not a sign or whitespace\n ((?P<yr>(\\d+(\\.\\d*)?|\\.\\d+)([eE][-+]?\\d+)?) \\s*, re.VERBOSE)#

scale#: Time scale.

subfmts = (('multi', None, None), ('yr', None, None), ('d', None, None), ('hr', None, None), ('min', None, None), ('s', None, None))#

value#

Methods Documentation

classmethod fill_value(subfmt)#

Return a value corresponding to J2000 (2000-01-01 12:00:00) in this format.

This is used as a fill value for masked arrays to ensure that any ERFA operations on the masked array will not fail due to the masked value.

static fix_comp_vals_overflow(comp_vals)[source]#

get_multi_comps(jd1, jd2)[source]#

parse_string(timestr)[source]#: Read time from a single string

set_jds(val1, val2)[source]#: Parse the time strings contained in val1 and get jd1, jd2.

to_value(parent=None, out_subfmt=None)[source]#

Return time representation from internal jd1 and jd2 in specified out_subfmt.

This is the base method that ignores parent and uses the value property to compute the output. This is done by temporarily setting self.out_subfmt and calling self.value. This is required for legacy Format subclasses prior to astropy 4.0 New code should instead implement the value functionality in to_value() and then make the value property be a simple call to self.to_value().

Parameters:

parentobject: Parent Time object associated with this TimeFormat object
out_subfmtstr or None: Output subformt (use existing self.out_subfmt if None)

Returns:

valuenumpy.array, numpy.ma.array: Array or masked array of formatted time representation values