plot_xshooter_model

from astropy.table import Table
from astropy.io import fits
import pandas as pd
import numpy as np



class XShooterEchelle(object):
    coef_types = ['cen', 'edgup', 'edglo']

    def __init__(self, order_table_fname):

        self.order_table = Table.read(order_table_fname).to_pandas()

        self.coefs = self._get_coefs()

    def _get_coefs(self):
        coefs = {}
        poly_deg = int(self.order_table.loc[0, 'DEGY'])
        for coef_type in self.coef_types:
            coef = self.order_table.loc[:,
                ['{0}coef{1}'.format(coef_type, i).upper()
                    for i in xrange(poly_deg + 1)]].values
            coefs[coef_type] = coef
        return coefs


    def get_y_array(self, order_id):
        return np.arange(self.order_table.loc[order_id, 'STARTY'],
        self.order_table.loc[order_id, 'ENDY'], )

    def calculate_order_trace(self, order_id, coef_type='cen'):
        coef_type = coef_type.upper()
        poly_deg = int(self.order_table.loc[order_id, 'DEGY'])
        coefs = self.order_table.loc[order_id,
        ['{0}{1}'.format(coef_type, i) for i in xrange(poly_deg + 1)]]
        y_array = self.get_y_array(order_id)
        return y_array, np.polyval(coefs[::-1], y_array)



if __name__ == '__main__':
    data = fits.getdata('../test_data/XSHOO.2011-07-22T23:34:46.953.fits')
    xshe = XShooterEchelle('ORDER_TAB_AFC_SLIT_VIS.fits')
    clf()
    imshow(data, vmin=1000, vmax=1500, cmap=cm.gray)
    yrange = np.arange(data.shape[0]) * 2
    x = np.polynomial.polynomial.polyval(yrange, xshe.coefs['edglo'].T)
    for order_id in xrange(15):
        plot(x[order_id]/2. + 2, yrange/2. + 2, color='red')

    x = np.polynomial.polynomial.polyval(yrange, xshe.coefs['edgup'].T)
    for order_id in xrange(15):
        plot(x[order_id]/2. + 2, yrange/2. + 2, color='blue')