#===========================================================================
#
# EpochConverter
#
#===========================================================================
"""EpochConverter module containing class EpochConverter."""
#===========================================================================
# Place all imports after here.
#
import matplotlib.units as units
import matplotlib.dates as date_ticker
from matplotlib.cbook import iterable
#
# Place all imports before here.
#===========================================================================
__all__ = [ 'EpochConverter' ]
#===========================================================================
class EpochConverter( units.ConversionInterface ):
""": A matplotlib converter class. Provides matplotlib conversion
functionality for Monte Epoch and Duration classes.
"""
# julian date reference for "Jan 1, 0001" minus 1 day because
# matplotlib really wants "Jan 0, 0001"
jdRef = 1721425.5 - 1
#------------------------------------------------------------------------
@staticmethod
def axisinfo( unit, axis ):
""": Returns information on how to handle an axis that has Epoch data.
= INPUT VARIABLES
- unit The units to use for a axis with Epoch data.
= RETURN VALUE
- Returns a matplotlib AxisInfo data structure that contains
minor/major formatters, major/minor locators, and default
label information.
"""
majloc = date_ticker.AutoDateLocator()
majfmt = date_ticker.AutoDateFormatter( majloc )
return units.AxisInfo( majloc = majloc,
majfmt = majfmt,
label = unit )
#------------------------------------------------------------------------
@staticmethod
def float2epoch( value, unit ):
""": Convert a matplotlib floating-point date into an Epoch of the
specified units.
= INPUT VARIABLES
- value The matplotlib floating-point date.
- unit The unit system to use for the Epoch.
= RETURN VALUE
- Returns the value converted to an Epoch in the sepcified time system.
"""
# Delay-load due to circular dependencies.
import mplTest.units as U
secPastRef = value * 86400.0 * U.UnitDbl( 1.0, 'sec' )
return U.Epoch( unit, secPastRef, EpochConverter.jdRef )
#------------------------------------------------------------------------
@staticmethod
def epoch2float( value, unit ):
""": Convert an Epoch value to a float suitible for plotting as a
python datetime object.
= INPUT VARIABLES
- value An Epoch or list of Epochs that need to be converted.
- unit The units to use for an axis with Epoch data.
= RETURN VALUE
- Returns the value parameter converted to floats.
"""
return value.julianDate( unit ) - EpochConverter.jdRef
#------------------------------------------------------------------------
@staticmethod
def duration2float( value ):
""": Convert a Duration value to a float suitible for plotting as a
python datetime object.
= INPUT VARIABLES
- value A Duration or list of Durations that need to be converted.
= RETURN VALUE
- Returns the value parameter converted to floats.
"""
return value.days()
#------------------------------------------------------------------------
@staticmethod
def convert( value, unit, axis ):
""": Convert value using unit to a float. If value is a sequence, return
the converted sequence.
= INPUT VARIABLES
- value The value or list of values that need to be converted.
- unit The units to use for an axis with Epoch data.
= RETURN VALUE
- Returns the value parameter converted to floats.
"""
# Delay-load due to circular dependencies.
import mplTest.units as U
isNotEpoch = True
isDuration = False
if ( iterable(value) and not isinstance(value, str) ):
if ( len(value) == 0 ):
return []
else:
return [ EpochConverter.convert( x, unit, axis ) for x in value ]
if ( isinstance(value, U.Epoch) ):
isNotEpoch = False
elif ( isinstance(value, U.Duration) ):
isDuration = True
if ( isNotEpoch and not isDuration and
units.ConversionInterface.is_numlike( value ) ):
return value
if ( unit == None ):
unit = EpochConverter.default_units( value, axis )
if ( isDuration ):
return EpochConverter.duration2float( value )
else:
return EpochConverter.epoch2float( value, unit )
#------------------------------------------------------------------------
@staticmethod
def default_units( value, axis ):
""": Return the default unit for value, or None.
= INPUT VARIABLES
- value The value or list of values that need units.
= RETURN VALUE
- Returns the default units to use for value.
"""
frame = None
if ( iterable(value) and not isinstance(value, str) ):
return EpochConverter.default_units( value[0], axis )
else:
frame = value.frame()
return frame
