[GRASS-dev] problem with parse_command python

[Luca Delucchi]

2010/12/29 Glynn Clements <glynn at gclements.plus.com>:
>>   # create string for east_north param
>>   coor = str(x) + ',' + str(y)
>
> This isn't necessary; you can pass numbers, lists and tuples to the
> grass.*_command() functions and they will be converted automatically.
>

ok, I change them with a list

>>   fields = grass.read_command('v.what',flags = 'a', map = map, east_north = coor)
>
> I suggest using the -g flag.
>

ok, but read down....

>>   # split the different features
>>   fields = fields.split('\n\n')
>
> This isn't correct. Without -g, the blank line occurs betwen the
> Layer: and Category: lines and the rest of the per-layer information.

I don't know if this is correct, look the answer of  "fields =
grass.read_command('v.what',flags = 'a', map = map_tiles, east_north =
pointslist)"

print fields

East: 636280
North: 5079748

Map: test_tile
Mapset: ortofoto_baldo
Type: Area
Sq Meters: 770560.000
Hectares: 77.056
Acres: 190.410
Sq Miles: 0.2975
Layer: 1
Category: 1

Driver: dbf
Database: /grassdata/patUTM32/ortofoto_baldo/dbf/
Table: test_tile
Key column: cat
cat : 1
location : /grassdata/patUTM32/ortofoto_baldo/cellhd/22_1683_tagliata
Layer: 1
Category: 13

Driver: dbf
Database: /grassdata/patUTM32/ortofoto_baldo/dbf/
Table: test_tile
Key column: cat
cat : 13
location : /grassdata/patUTM32/ortofoto_baldo/cellhd/24a_3001_tagliata
Layer: 2
Category: 2

I think the first word of new feature is Driver, I wrong?

> You need to scan through the lines and start a new dictionary whenever
> you find a "Layer" line.
>

ok, here the new code....

def vector_what(map,coor):
  """!Return the result of v.what using the map and coordinates passed

  @param map vector map name
  @param coor a list of x,y coordinates

  @return parsed output in dictionary

  """
  result = {}
  # create string for east_north param
  fields = grass.read_command('v.what',flags = 'ag', map = map,
east_north = coor)
  #split lines
  fields = fields.splitlines()
  # value for number of features
  value = 0
  # create a temporary dictionary
  temp_dic = {}
  # for each line
  for field in fields:
    # split key and value
    kv = field.split('=', 1)
    if len(kv) > 1:
      #Start the new feature
      if kv[0].strip() == 'Driver':
	# if value is 0 dictionary contain general information about map
	if value == 0:
	  result['general'] = temp_dic
	# else features
	else:
	  result['feature'+str(value)] = temp_dic
	# create a new temporary dictionary
	temp_dic = {}
	# add driver to the new dictionary
	temp_dic[kv[0].strip()] = str(kv[1])
	# value for the new feature
	value = value + 1
      else:
	# add value to the dictionary
	temp_dic[kv[0].strip()] = str(kv[1])
    # add the last feature
    result['feature'+str(value)] = temp_dic
  return result


> --
> Glynn Clements <glynn at gclements.plus.com>
>


thanks
Luca

www.lucadelu.org