"""A helper class to load data from SpectraRay ASCII Files.
It only supplies a rudimentary loading of standard psi/delta values
and misses some other features.
"""
import re
import pandas as pd
from packaging.version import Version, parse
from ..utils import calc_rho, convert_delta_range, detect_encoding
[docs]
def read_spectraray_psi_delta(
fname: str, sep: str = r"\s+", decimal: str = "."
) -> pd.DataFrame:
r"""Read a psi/delta spectraray ascii file.
Args:
fname (str): Filename of the measurement ascii file.
sep (str, optional): Data separator in the datafile. Defaults to "\s+".
decimal (str, optional): Decimal separator in the datafile. Defaults to ".".
Returns:
pd.DataFrame: DataFrame containing the psi/delta data in
the format to be further processes inside pyElli.
"""
# detect encoding
encoding = detect_encoding(fname)
# read data and drop empty column
psi_delta_df = pd.read_csv(
fname,
encoding=encoding,
index_col=0,
header=None,
sep=sep,
decimal=decimal,
skiprows=1,
)
psi_delta_df.dropna(axis="columns", how="all", inplace=True)
# index data correctly
psi_delta_df.index.name = "Wavelength"
with open(fname) as f:
header = f.readlines()[0]
aois = list(map(float, re.split(sep, header)[3::2]))
index = pd.MultiIndex.from_product(
[aois, ["Ψ", "Δ"]], names=["Angle of Incidence", ""]
)
psi_delta_df.columns = index
# reorder dataframe
if Version("2.2") <= parse(pd.__version__) < Version("3.0"):
psi_delta_df = psi_delta_df.stack(0, future_stack=True)
else:
psi_delta_df = psi_delta_df.stack(0)
psi_delta_df = psi_delta_df.reorder_levels(["Angle of Incidence", "Wavelength"])
psi_delta_df.sort_index(axis=0, inplace=True)
psi_delta_df.sort_index(axis=1, ascending=False, inplace=True)
# convert delta range
psi_delta_df.loc[:, "Δ"] = convert_delta_range(psi_delta_df.loc[:, "Δ"], -180, 180)
return psi_delta_df
[docs]
def read_spectraray_mmatrix(
fname: str, sep: str = r"\s+", decimal: str = "."
) -> pd.DataFrame:
r"""Read a mueller matrix spectraray ascii file.
Only reads the first entry and does not support reading multiple angles.
For multiple angles you have to save the data in multiple files.
Args:
fname (str): Filename of the measurement ascii file.
sep (str, optional): Data separator in the datafile. Defaults to "\s+".
decimal (str, optional): Decimal separator in the datafile. Defaults to ".".
Returns:
pd.DataFrame: DataFrame containing the psi/delta data in
the format to be further processes inside pyElli.
"""
encoding = detect_encoding(fname)
mueller_matrix = pd.read_csv(
fname, encoding=encoding, sep=sep, decimal=decimal, index_col=0
).iloc[:, -17:-1]
mueller_matrix.index.name = "Wavelength"
mueller_matrix.columns = [
"M11",
"M12",
"M13",
"M14",
"M21",
"M22",
"M23",
"M24",
"M31",
"M32",
"M33",
"M34",
"M41",
"M42",
"M43",
"M44",
]
return mueller_matrix
[docs]
def read_spectraray_rho(
fname: str, sep: str = r"\s+", decimal: str = "."
) -> pd.DataFrame:
r"""Read a psi/delta spectraray ascii file and converts it to rho values.
Args:
fname (str): Filename of the measurement ascii file.
sep (str, optional): Data separator in the datafile. Defaults to "\s+".
decimal (str, optional): Decimal separator in the datafile. Defaults to ".".
Returns:
pd.DataFrame: DataFrame containing the rho data in
the format to be further processes inside pyElli.
"""
psi_delta = read_spectraray_psi_delta(fname, sep, decimal)
return calc_rho(psi_delta)