#!/usr/bin/env python
# XDS_ASCII.py
# Maintained by G.Winter
#
#   Copyright (C) 2008 CCLRC, Graeme Winter
#
#   This code is distributed under the BSD license, a copy of which is
#   included in the root directory of this package.
#
# 22nd February 2008
#
# Code for manipulating XDS_ASCII files from XDS CORRECT.
#

import os

def remove_misfits(xdsin, xdsout):
  '''Read through the XDS_ASCII input file and remove the misfit
  reflections (SD < 0.0) - write out the remains to xdsout.'''

  if xdsin == xdsout:
    raise RuntimeError, 'xdsin and xdsout same file'

  if not os.path.exists(xdsin):
    raise RuntimeError, 'xdsin does not exist'

  fout = open(xdsout, 'w')

  ignored = 0

  for record in open(xdsin, 'r').readlines():

    if not record.strip():
      continue

    if record[0] == '!':
      fout.write(record)
      continue

    values = map(float, record.split())

    if values[4] > 0.0:
      fout.write(record)
      continue
    else:
      ignored += 1

  fout.close()

  return ignored