List Selected Stations with Longitude / Latitude

[yasuit21]

Background

• A function to return stations with Lon/Lat is helpful to plot them in a map.
• Client.get_seleced_stations() only returns the number of selected stations, not the station info.
• Here, add Client.list_selected_stations() to show selected stations with Lon/Lat data!

Feature

• Client.list_selected_stations() returns a dict containing stations as keys.
• For each value, a dict with 'longitude' and 'latitude' as keys.
• len() returns the number of selected stations, the same feature to Client.get_seleced_stations().

Example

>>> client = Client("username", "password")
>>> stations = client.list_selected_stations(code='0101', parser='lxml')
>>> stations
{'N.TRGH': {'longitude': 136.0303, 'latitude': 35.639},
 'N.MIKH': {'longitude': 135.8694, 'latitude': 35.5587},
 ...,
 'N.NAKH': {'longitude': 132.9524, 'latitude': 33.0754}}

>>> len(stations)
23
>>> [*stations.keys()]
['N.TRGH',
 'N.MIKH',
  ...,
 'N.NAKH']

>>> print(*stations['N.MIKH'].values())
135.8694 35.5587

Note

• Need to install beautifulsoup4 to run this function (I did not touch setup.py and requirements.txt)
• Can run faster if the parser lxml is installed, as the default parser. If not, html.parser is used in BeautifulSoup.
• This func can be renamed to get_seleced_stations()?

[seisman]

@yasuit21 Thanks for your contribution! It looks like a useful feature.

I think the feature should be merged into get_selected_stations function, but I'm a little hesitate to add one more dependency (beautifulsoup4), that's why I use regrex in the codes.

[yasuit21]

Thanks. I have changed as below:

• Used the standard lib html.parser instead of beautifulsoup4.
• New class _GrepTableData() in this function, which is inherited from html.parser.HTMLParser
• _GrepTableData() searchs all tags for station names
• Removed the parser argument.

No dependency is added. Would you check?

[seisman]

@yasuit21 Your changes work well. The CI jobs fail because your fork can't access some secret settings in this repository. Don't worry. I'll run the tests locally.

I have two more suggestions:

1. As you already suggested, it's a good idea to rename your function to get_selected_stations(). The old function returns the number of the selected stations, and your new function returns a list/dict of the selected stations. It's a great improvement, although it's backward incompatible.
2. Your function returns a list/dict of selected stations. Actually, HinetPy has a class for Station:
   

   HinetPy/HinetPy/client.py

   Lines 1341 to 1357 in 6cbf4cc

   	class Station(object):
   	"""
   	Class for Stations.
   	"""
   	def __init__(self, code, name, latitude, longitude, elevation):
   	self.code = code
   	self.name = name
   	self.latitude = float(latitude)
   	self.longitude = float(longitude)
   	self.elevation = float(elevation)
   	def __str__(self):
   	string = "{} {} {} {} {}".format(
   	self.code, self.name, self.latitude, self.longitude, self.elevation
   	)
   	return string

   
   Perhaps your function can return a list of Station?

[yasuit21]

@seisman Thank you for suggestions.

1. Renamed the new function to get_selected_stations() and old one to _get_selected_stations(). Also renamed that used in _get_allowed_span().

2. Returns a list of Station instances instead of a dict. I have added examples to call. It may be more useful if print() returns station info, like an Inventory class of ObsPy.

3. Put _GrepTableData outside the Client class (line 1466-). I will return it to the original position if any problems.