Custom converter for Massimo

Custom_Converter_for_Massimo.ipynb

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   "cell_type": "code",
   "execution_count": 1,
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   "source": [
    "import numpy as np\n",
    "from astropy.io import ascii"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {
    "collapsed": true
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   "outputs": [],
   "source": [
    "filename = 'zspec.txt'  # Replace this with actual filename"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": [
    "# Define a custom converter.\n",
    "# This is just quick proof of concept, optimize as needed.\n",
    "def myconv(arr):\n",
    "    \"\"\"Replace D with E for each row in column.\"\"\"\n",
    "    arr = [x.replace('D', 'E') for x in arr]\n",
    "    return np.array(arr, dtype='float64')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": [
    "# Tell reader to apply custom converters to columns of interest.\n",
    "converters = {'col2': [(myconv, ascii.core.FloatType)],\n",
    "              'col3': [(myconv, ascii.core.FloatType)]}"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {
    "collapsed": false
   },
   "outputs": [],
   "source": [
    "# Read the file as you did, but with custom converters.\n",
    "data = ascii.read(filename, format='fixed_width_no_header',\n",
    "                  names=('wl_A', '10_FL_DF', '10_BL_DF','other'),\n",
    "                  col_starts=(0, 13, 25, 37), col_ends=(12, 24, 36, 137),\n",
    "                  converters=converters)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {
    "collapsed": false
   },
   "outputs": [],
   "source": [
    "# Delete the useless column (so I can print it nicely)\n",
    "del data['other']"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "wl_A 10_FL_DF 10_BL_DF\n",
      "---- -------- --------\n",
      " 1.0 -89.0947 -89.0947\n",
      " 1.0 -89.0947 -89.0947\n"
     ]
    }
   ],
   "source": [
    "data.pprint()"
   ]
  }
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   "file_extension": ".py",
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   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython3",
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just perfect!