"""A helper class to load data from SpectraRay ASCII Files
"""
import pandas as pd
import scipy.constants as sc
from .dispersions import DispersionTableEpsilon
from .utils import calc_rho
[docs]class SpectraRay():
def __init__(self, path: str) -> None:
self.spectraray_path = path
[docs] def loadDispersionTable(self, fname: str) -> DispersionTableEpsilon:
start = 0
stop = 0
with open(self.spectraray_path + fname, 'r') as f:
line = f.readline()
cnt = 0
while line:
if line.strip() == 'Begin of array':
start = cnt + 1
if line.strip() == 'End of array':
stop = cnt
line = f.readline()
cnt += 1
if line.startswith('Units='):
x_unit = line.split('=')[1].split(',')[0]
df = pd.read_csv(self.spectraray_path + fname,
delim_whitespace=True,
skiprows=start, nrows=stop-start,
index_col=0, usecols=[0, 1, 2],
names=[x_unit, 'ϵ1', 'ϵ2'])
if x_unit == 'Wavelength':
return DispersionTableEpsilon(df.index, df.loc[:, 'ϵ1'] + 1j * df.iloc[:, 'ϵ2'])
elif x_unit == 'eV':
return DispersionTableEpsilon(SpectraRay.eV2nm(df.index), df.loc[:, 'ϵ1'] + 1j * df.loc[:, 'ϵ2'])
[docs] @staticmethod
def read_psi_delta_file(fname: str, decimal: str = '.') -> pd.DataFrame:
return pd.read_csv(fname,
index_col=0,
sep=r'\s+',
decimal=decimal,
usecols=[0, 1, 2],
names=['Wavelength', 'Ψ', 'Δ'],
skiprows=1)
[docs] @staticmethod
def read_mmatrix(fname: str, decimal: str = '.') -> pd.DataFrame:
"""Read a Mueller matrix from a Sentech ASCII file.
Save the file in SpectraRay under Save As -> Ascii (.txt)"""
mueller_matrix = pd.read_csv(fname,
sep=r'\s+',
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] @staticmethod
def read_rho(fname: str, decimal: str = '.') -> pd.DataFrame:
psi_delta = SpectraRay.read_psi_delta_file(fname, decimal)
return calc_rho(psi_delta)
[docs] @staticmethod
def eV2nm(wlen):
return sc.value('Planck constant in eV s') * sc.c * 1e9 / wlen