Source Code for Module pydrizzle.imtype

  1  import types 
  2  import pyfits 
  3  from pytools import fileutil 
  4   
  5 -class Imtype: 
  6      """ Class which determines the format of the file, how to access the 
  7          SCI data array, and if available, any DQ array as well.  The syntax 
  8          for accessing the data will then be kept as attributes for use by 
  9          other tasks/classes. 
 10   
 11          Parameters: 
 12              filename    -   name of file to be examined 
 13              handle      -   PyFITS-style file handle for image 
 14              dqsuffix    -   suffix for DQ array for non-MEF files 
 15   
 16          If 'dqsuffix' is not provided and the file is GEIS formatted, 
 17          then this class will search for a '.c1h' extension by default, 
 18          and return None if not found. 
 19   
 20      """ 
 21 -    def __init__(self,filename,handle=None,dqsuffix=None): 
 22   
 23          self.handle = handle 
 24          self.filename = filename 
 25          self.dqfile = filename 
 26   
 27          self.seperator = ','            # Used for parsing EXTN syntax 
 28          self.dq_suffix = dqsuffix 
 29          self.dq_extname = 'dq' 
 30          self.sci_extname = 'sci' 
 31          self.sci_extn = '['+self.sci_extname+',1]'   # default specification for SCI extension/group 
 32          self.dq_extn = '['+self.dq_extname+',1]'     # default specification for DQ extension/group 
 33   
 34          if filename: 
 35              if filename.find('.fits') > -1: 
 36                  if handle and len(handle) == 1: 
 37                      # Simple FITS image: 
 38                      #    Let the Exposure class find the SCI array. 
 39                      self.sci_extn = None 
 40                      self.dq_extn = None 
 41                      self.dq_extname = None 
 42                      self.sci_extname = None 
 43              else: 
 44                  # GEIS image 
 45                  self.seperator = '[' 
 46                  if not dqsuffix: 
 47                      _dqsuffix = '.c1h' 
 48                      _indx = filename.rfind('.') 
 49                      if fileutil.findFile(filename[:_indx]+_dqsuffix): 
 50                          self.dq_suffix = '.c1h' 
 51                      else: 
 52                          self.dq_suffix = None 
 53   
 54                  self.sci_extn = '[1]' 
 55                  self.dq_extn = '[1]' 
 56                  self.dq_extname = '1' 
 57                  self.sci_extname = '1' 
 58   
 59   
 60 -    def makeSciName(self,extver,section=None): 
 61          """ Returns the properly formatted filename to access the SCI extension.""" 
 62   
 63          if section == None: 
 64              _extname = self.filename+self._setSciExtn(extn=extver) 
 65          else: 
 66              _extname = self.filename+'['+str(section)+']' 
 67   
 68          return _extname 
 69   
 70 -    def makeDQName(self,extver): 
 71          """ Create the name of the file which contains the DQ array. 
 72              For multi-extension FITS files, this will be the same file 
 73              as the SCI array. 
 74          """ 
 75   
 76          if not self.dq_suffix: 
 77              _dqname = self.dqfile 
 78          else: 
 79              _dqname = fileutil.buildNewRootname(self.dqfile,extn=self.dq_suffix) 
 80   
 81          if self.dq_extn: 
 82              _dqname += self._setDQExtn(extn=extver) 
 83          elif self.dq_suffix: 
 84              _dqname = _dqname+'[0]' 
 85          else: 
 86              _dqname = None 
 87   
 88          return _dqname 
 89   
 90 -    def _setDQExtn(self, extn=None): 
 91          """ Builds extension specification for accessing DQ extension/group. 
 92          """ 
 93          if extn != None: 
 94              if self.dq_extn: 
 95                  _lensep = len(self.seperator) 
 96                  _indx = self.dq_extn.find(self.seperator) + _lensep 
 97                  return self.dq_extn[:_indx]+repr(extn)+self.dq_extn[_indx+1:] 
 98              else: 
 99                  return '' 
100          else: 
101              return self.dq_extn 
102   
103 -    def _setSciExtn(self,extn=None): 
104          """ Builds extension specification for accessing SCI extension/group. 
105          """ 
106          if extn != None: 
107              if self.sci_extn: 
108                  _lensep = len(self.seperator) 
109                  _indx = self.sci_extn.find(self.seperator) + _lensep 
110                  return self.sci_extn[:_indx]+repr(extn)+self.sci_extn[_indx+1:] 
111              else: 
112                  return '' 
113          else: 
114              return self.sci_extn 
115