Source Code for Module generic_fns.frq

  1  ############################################################################### 
  2  #                                                                             # 
  3  # Copyright (C) 2008-2012 Edward d'Auvergne                                   # 
  4  #                                                                             # 
  5  # This file is part of the program relax (http://www.nmr-relax.com).          # 
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  8  # it under the terms of the GNU General Public License as published by        # 
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 10  # (at your option) any later version.                                         # 
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 12  # This program is distributed in the hope that it will be useful,             # 
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 15  # GNU General Public License for more details.                                # 
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 18  # along with this program.  If not, see <http://www.gnu.org/licenses/>.       # 
 19  #                                                                             # 
 20  ############################################################################### 
 21   
 22  # Module docstring. 
 23  """Module for manipulating the spectrometer frequency of experiments.""" 
 24   
 25  # Python module imports. 
 26  from warnings import warn 
 27   
 28  # relax module imports. 
 29  from generic_fns import pipes 
 30  from relax_errors import RelaxError 
 31  from relax_warnings import RelaxWarning 
 32   
 33   
 34 -def get_values(): 
 35      """Return a list of all the current frequencies. 
 36   
 37      @return:    The frequency list for the current data pipe. 
 38      @rtype:     list of float 
 39      """ 
 40   
 41      # No frequency data. 
 42      if not hasattr(cdp, 'frq'): 
 43          return [] 
 44   
 45      # The frequency values. 
 46      values = cdp.frq.values() 
 47   
 48      # Build a list of the unique frequencies. 
 49      frq = [] 
 50      for value in values: 
 51          if value not in frq: 
 52              frq.append(value) 
 53   
 54      # Return the frqs. 
 55      return frq 
 56   
 57   
 58 -def set(id=None, frq=None, units='Hz'): 
 59      """Set the spectrometer frequency of the experiment. 
 60   
 61      @keyword id:    The experimental identification string (allowing for multiple experiments per data pipe). 
 62      @type id:       str 
 63      @keyword frq:   The spectrometer frequency in Hertz. 
 64      @type frq:      float 
 65      @keyword units: The units of frequency.  This can be one of "Hz", "kHz", "MHz", or "GHz". 
 66      @type units:    str 
 67      """ 
 68   
 69      # Test if the current data pipe exists. 
 70      pipes.test() 
 71   
 72      # Set up the dictionary data structure if it doesn't exist yet. 
 73      if not hasattr(cdp, 'frq'): 
 74          cdp.frq = {} 
 75   
 76      # Test the frequency has not already been set. 
 77      if id in cdp.frq and cdp.frq[id] != frq: 
 78          raise RelaxError("The frequency for the experiment '%s' has already been set to %s Hz." % (id, cdp.frq[id])) 
 79   
 80      # Unit conversion. 
 81      if units == 'Hz': 
 82          conv = 1.0 
 83      elif units == 'kHz': 
 84          conv = 1e3 
 85      elif units == 'MHz': 
 86          conv = 1e6 
 87      elif units == 'GHz': 
 88          conv = 1e9 
 89      else: 
 90          raise RelaxError("The frequency units of '%s' are unknown." % units) 
 91   
 92      # Set the frequency. 
 93      cdp.frq[id] = frq * conv 
 94   
 95      # Warnings. 
 96      if cdp.frq[id] < 1e8: 
 97          warn(RelaxWarning("The proton frequency of %s Hz appears to be too low." % cdp.frq[id])) 
 98      if cdp.frq[id] > 2e9: 
 99          warn(RelaxWarning("The proton frequency of %s Hz appears to be too high." % cdp.frq[id])) 
100