code: def getPosNew(data):
      
      pos = data.geno['col_header']['pos'][:]
      chrom= data.geno['col_header']['chrom'][:]
      n_chroms = chrom.max()
      pos_new = []
      for chrom_i in range(1,n_chroms+1):
          I = chrom==chrom_i
          _pos = pos[I]
          for i in range(1,_pos.shape[0]):
              if not _pos[i]>_pos[i-1]:
                  _pos[i:]=_pos[i:]+_pos[i-1]
          pos_new.append(_pos)
      pos_new = SP.concatenate(pos_new)
      return pos_new
docs: get Fixed position