from esbo_etc.lib.helpers import error from scipy.interpolate import interp1d import astropy.units as u import math from typing import Union import logging from astropy.io import ascii import re class SpectralQty: """ A class to hold and work with spectral quantities """ def __init__(self, wl: u.Quantity, qty: u.Quantity, extrapolate: bool = False) -> "SpectralQty": """ Initialize a new spectral quantity Parameters ---------- wl : Quantity The binned wavelengths qty : Quantity The quantity values corresponding to the binned wavelengths. If the values are supplied without a unit, they are assumed to be dimensionless. extrapolate : bool Whether extrapolation should be allowed. If disabled, the spectrum will be truncated and a warning given. Returns ------- sqty : SpectralQty The created spectral quantity. """ # Check if both lengths are equal if len(wl) == len(qty): # check if units are given. If not, add a dimensionless unit if hasattr(wl, "unit"): self.wl = wl else: self.wl = wl * u.dimensionless_unscaled if hasattr(qty, "unit"): self.qty = qty else: self.qty = qty * u.dimensionless_unscaled else: error("Lengths not matching") self._extrapolate = extrapolate @classmethod def fromFile(cls, file: str, wl_unit_default: u.Quantity = None, qty_unit_default: u.Quantity = None, extrapolate: bool = False) -> "SpectralQty": """ Initialize a new spectral quantity and read the values from a file Parameters ---------- file : str Path to the file to read the values from. The file needs to provide two columns: wavelength and the corresponding spectral quantity. The format of the file will be guessed by `astropy.io.ascii.read(). If the file doesn't provide units via astropy's enhanced CSV format, the units will be read from the column headers or otherwise assumed to be *wl_unit_default* and *qty_unit_default*. wl_unit_default : Quantity Default unit to be used for the wavelength column if no units are provided by the file. qty_unit_default : Quantity Default unit to be used for the quantity column if no units are provided by the file. extrapolate : bool Whether extrapolation should be allowed. If disabled, the spectrum will be truncated and a warning given. Returns ------- sqty : SpectralQty The created spectral quantity. """ # Read the file data = ascii.read(file) # Check if units are given if data[data.colnames[0]].unit is None: # Convert values to float data[data.colnames[0]] = list(map(float, data[data.colnames[0]])) data[data.colnames[1]] = list(map(float, data[data.colnames[1]])) # Check if units are given in column headers if all([re.search("\\[.+\\]", x) for x in data.colnames]): # Extract units from headers and apply them on the columns units = [u.Unit(re.findall("(?<=\\[).+(?=\\])", x)[0]) for x in data.colnames] data[data.colnames[0]].unit = units[0] data[data.colnames[1]].unit = units[1] # Use default units elif wl_unit_default is not None and qty_unit_default is not None: data[data.colnames[0]].unit = wl_unit_default data[data.colnames[1]].unit = qty_unit_default return cls(data[data.colnames[0]].quantity, data[data.colnames[1]].quantity, extrapolate=extrapolate) def __eq__(self, other) -> bool: """ Check if this object is equal to another object Parameters ---------- other : SpectralQty Object to compare with Returns ------- res : bool Result of the comparison """ return self.wl.unit == other.wl.unit and self.qty.unit == other.qty.unit and \ len(self.wl) == len(other.wl) and len(self.qty) == len(other.qty) and \ all([math.isclose(x, y, rel_tol=1e-5) for x, y in zip(self.wl.value, other.wl.value)]) and \ all([math.isclose(x, y, rel_tol=1e-5) for x, y in zip(self.qty.value, other.qty.value)]) def __add__(self, other: Union[int, float, u.Quantity, "SpectralQty"]) -> "SpectralQty": """ Calculate the sum with another object Parameters ---------- other : Union[int, float, u.Quantity, "SpectralQty"] Addend to be added to this object. If the binning of the object on the right hand side differs from the binning of the left object, the object on the right hand side will be rebinned. Returns ------- sum : SpectralQty The sum of both objects """ # Summand is of type int or float, use same unit if isinstance(other, int) or isinstance(other, float): return SpectralQty(self.wl, self.qty + other * self.qty.unit) # Summand is of type Quantity elif isinstance(other, u.Quantity): if other.unit == self.qty.unit: return SpectralQty(self.wl, self.qty + other) else: raise TypeError("Units are not matching for addition.") # Summand is of type SpectralQty else: if other.wl.unit.is_equivalent(self.wl.unit) and other.qty.unit.is_equivalent(self.qty.unit): # Wavelengths are matching, just add the quantities if len(self.wl) == len(other.wl) and all(self.wl == other.wl): return SpectralQty(self.wl, self.qty + other.qty) # Wavelengths are not matching, rebinning needed else: # Rebin addend other_rebinned = other.rebin(self.wl) if len(self.wl) == len(other_rebinned.wl) and all(self.wl == other_rebinned.wl): return SpectralQty(self.wl, self.qty + other_rebinned.qty) else: # Wavelengths are still not matching as extrapolation is disabled, rebin this spectral quantity return SpectralQty(other_rebinned.wl, self.rebin(other_rebinned.wl).qty + other_rebinned.qty) else: error("Units are not matching for addition.") __radd__ = __add__ def __sub__(self, other: Union[int, float, u.Quantity, "SpectralQty"]) -> "SpectralQty": """ Calculate the difference to another object Parameters ---------- other : Union[int, float, u.Quantity, "SpectralQty"] Subtrahend to be subtracted from this object. If the binning of the object on the right hand side differs from the binning of the left object, the object on the right hand side will be rebinned. Returns ------- sum : SpectralQty The difference of both objects """ # Subtrahend is of type int or float, use same unit if isinstance(other, int) or isinstance(other, float): return SpectralQty(self.wl, self.qty - other * self.qty.unit) # Subtrahend is of type Quantity elif isinstance(other, u.Quantity): if other.unit == self.qty.unit: return SpectralQty(self.wl, self.qty - other) else: raise TypeError('Units are not matching for subtraction.') # Subtrahend is of type SpectralQty else: if other.wl.unit.is_equivalent(self.wl.unit) and other.qty.unit.is_equivalent(self.qty.unit): # Wavelengths are matching, just subtract the quantities if len(self.wl) == len(other.wl) and all(self.wl == other.wl): return SpectralQty(self.wl, self.qty - other.qty) # Wavelengths are not matching, rebinning needed else: # Rebin subtrahend other_rebinned = other.rebin(self.wl) if len(self.wl) == len(other_rebinned.wl) and all(self.wl == other_rebinned.wl): return SpectralQty(self.wl, self.qty - other_rebinned.qty) else: # Wavelengths are still not matching as extrapolation is disabled, rebin this spectral quantity return SpectralQty(other_rebinned.wl, self.rebin(other_rebinned.wl).qty - other_rebinned.qty) else: error("Units are not matching for substraction.") def __mul__(self, other: Union[int, float, u.Quantity, "SpectralQty"]) -> "SpectralQty": """ Calculate the product with another object Parameters ---------- other : Union[int, float, u.Quantity, "SpectralQty"] Factor to be multiplied with this object. If the binning of the object on the right hand side differs from the binning of the left object, the object on the right hand side will be rebinned. Returns ------- sum : SpectralQty The product of both objects """ # Factor is of type int, float or Quantity, just multiply if isinstance(other, int) or isinstance(other, float) or isinstance(other, u.Quantity): return SpectralQty(self.wl, self.qty * other) # Factor is of type SpectralQty else: if other.wl.unit.is_equivalent(self.wl.unit): # Wavelengths are matching, just multiply the quantities if len(self.wl) == len(other.wl) and all(self.wl == other.wl): return SpectralQty(self.wl, self.qty * other.qty) # Wavelengths are not matching, rebinning needed else: # Rebin factor other_rebinned = other.rebin(self.wl) if len(self.wl) == len(other_rebinned.wl) and all(self.wl == other_rebinned.wl): return SpectralQty(self.wl, self.qty * other_rebinned.qty) else: # Wavelengths are still not matching as extrapolation is disabled, rebin this spectral quantity return SpectralQty(other_rebinned.wl, self.rebin(other_rebinned.wl).qty * other_rebinned.qty) else: error("Units are not matching for multiplication.") __rmul__ = __mul__ def rebin(self, wl: u.Quantity) -> "SpectralQty": """ Resample the spectral quantity sqty(wl) over the new grid wl, rebinning if necessary, otherwise interpolates. Copied from ExoSim (https://github.com/ExoSim/ExoSimPublic). Parameters ---------- wl : Quantity new binned wavelengths Returns ------- sqty : SpectralQty The rebinned spectral quantity """ if wl.unit != self.wl.unit: error("Mismatching units for rebinning: " + wl.unit + ", " + self.wl.unit) if not self._extrapolate: if min(wl) < min(self.wl) or max(wl) > max(self.wl): logging.warning("Extrapolation disabled, bandwidth will be reduced.") # Remove new wavelengths where extrapolation would have been necessary wl = [x.value for x in wl if min(self.wl) <= x <= max(self.wl)] * wl.unit f = interp1d(self.wl, self.qty.value, fill_value="extrapolate") return SpectralQty(wl, f(wl.to(self.wl.unit)) * self.qty.unit)