Bokeh Geoviews verwenden Lat/Long oder UTM?

Question

Ich versuche, den Zillow-Datensatz mit Bokeh mit Geoviews und Datashadern zu plotten, aber ich habe die verdammte Zeit, ihn zum Laufen zu bringen. Ich bin in der Lage, die Daten auf einer kartesischen Ebene fein zu zeichnen, aber wenn ich versuche, die Daten mit einer Karte zu überlagern, laufe ich auf Fehler.

Ich habe Code aus dem census-hv Beispiel auf dem Datashader Github verwendet. Ich glaube mein Problem ist, dass es nach den Koordinaten sucht, die in UTM nicht Lat/Long sind. Weil der Code funktioniert, wenn ich meine Koordinaten mit ein paar tausend multipliziert habe. Die Punkte werden dann oberhalb der Karte im Leerraum platziert. Wenn ich versuche, die richtigen Breiten-/Längenkoordinaten zu zeichnen, erhalte ich die folgenden Fehler.

Kann mir bitte jemand in Richtung einer Karte zeigen, die Lat verwendet/Lange

>>>props.head() 
longitude latitude 
0 -118.654084 34.144442 
1 -118.625364 34.140430 
2 -118.394633 33.989359 
3 -118.437206 34.148863 
4 -118.385816 34.194168 

import pandas as pd 
import holoviews as hv 
import geoviews as gv 
import datashader as ds 

from bokeh.models import WMTSTileSource 
from holoviews.operation.datashader import datashade, dynspread 
hv.notebook_ex 

tension('bokeh') 

%%opts Overlay [width=900 height=525 xaxis=None yaxis=None] 

geomap = gv.WMTS(WMTSTileSource(url=\ 
    'https://server.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer/tile/{Z}/{Y}/{X}.jpg')) 

points = hv.Points(gv.Dataset(props, kdims=['longitude', 'latitude'])) 
# color_key = {'w':'aqua', 'b':'lime', 'a':'red', 'h':'fuchsia', 'o':'yellow' } 
race = datashade(points, x_sampling=50, y_sampling=50, 
       element_type=gv.Image) 
geomap * race 

RETURNS ERROR: 
WARNING:root:dynamic_operation: Exception raised in callable 

'dynamic_operation' of type 'function'. 
Invoked as dynamic_operation(height=400, scale=1.0, width=400, x_range=None, y_range=None) 
--------------------------------------------------------------------------- 
ValueError        Traceback (most recent call last) 
/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/IPython/core/formatters.py in __call__(self, obj) 
    305     pass 
    306    else: 
--> 307     return printer(obj) 
    308    # Finally look for special method names 
    309    method = get_real_method(obj, self.print_method) 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/ipython/display_hooks.py in pprint_display(obj) 
    255  if not ip.display_formatter.formatters['text/plain'].pprint: 
    256   return None 
--> 257  return display(obj, raw=True) 
    258 
    259 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/ipython/display_hooks.py in display(obj, raw, **kwargs) 
    241  elif isinstance(obj, (HoloMap, DynamicMap)): 
    242   with option_state(obj): 
--> 243    html = map_display(obj) 
    244  else: 
    245   return repr(obj) if raw else IPython.display.display(obj, **kwargs) 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/ipython/display_hooks.py in wrapped(element) 
    127   try: 
    128    html = fn(element, 
--> 129      max_frames=OutputMagic.options['max_frames']) 
    130 
    131    # Only want to add to the archive for one display hook... 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/ipython/display_hooks.py in map_display(vmap, max_frames) 
    196   return None 
    197 
--> 198  return render(vmap) 
    199 
    200 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/ipython/display_hooks.py in render(obj, **kwargs) 
    57  if renderer.fig == 'pdf': 
    58   renderer = renderer.instance(fig='png') 
---> 59  return renderer.html(obj, **kwargs) 
    60 
    61 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/plotting/renderer.py in html(self, obj, fmt, css, comm, **kwargs) 
    253   code to initialize a Comm, if the plot supplies one. 
    254   """ 
--> 255   plot, fmt = self._validate(obj, fmt) 
    256   figdata, _ = self(plot, fmt, **kwargs) 
    257   if css is None: css = self.css 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/plotting/renderer.py in _validate(self, obj, fmt) 
    189   if isinstance(obj, tuple(self.widgets.values())): 
    190    return obj, 'html' 
--> 191   plot = self.get_plot(obj, renderer=self) 
    192 
    193   fig_formats = self.mode_formats['fig'][self.mode] 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/plotting/renderer.py in get_plot(self_or_cls, obj, renderer) 
    164   """ 
    165   # Initialize DynamicMaps with first data item 
--> 166   initialize_dynamic(obj) 
    167 
    168   if not isinstance(obj, Plot) and not displayable(obj): 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/plotting/util.py in initialize_dynamic(obj) 
    173    continue 
    174   if not len(dmap): 
--> 175    dmap[dmap._initial_key()] 
    176 
    177 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/core/spaces.py in __getitem__(self, key) 
    942   # Not a cross product and nothing cached so compute element. 
    943   if cache is not None: return cache 
--> 944   val = self._execute_callback(*tuple_key) 
    945   if data_slice: 
    946    val = self._dataslice(val, data_slice) 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/core/spaces.py in _execute_callback(self, *args) 
    791 
    792   with dynamicmap_memoization(self.callback, self.streams): 
--> 793    retval = self.callback(*args, **kwargs) 
    794   return self._style(retval) 
    795 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/core/spaces.py in __call__(self, *args, **kwargs) 
    489   # Nothing to do for callbacks that accept no arguments 
    490   (inargs, inkwargs) = (args, kwargs) 
--> 491   if not args and not kwargs: return self.callable() 
    492   inputs = [i for i in self.inputs if isinstance(i, DynamicMap)] 
    493   streams = [] 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/core/overlay.py in dynamic_mul(*args, **kwargs) 
    27    from .spaces import Callable 
    28    def dynamic_mul(*args, **kwargs): 
---> 29     element = other[args] 
    30     return self * element 
    31    callback = Callable(dynamic_mul, inputs=[self, other]) 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/core/spaces.py in __getitem__(self, key) 
    942   # Not a cross product and nothing cached so compute element. 
    943   if cache is not None: return cache 
--> 944   val = self._execute_callback(*tuple_key) 
    945   if data_slice: 
    946    val = self._dataslice(val, data_slice) 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/core/spaces.py in _execute_callback(self, *args) 
    791 
    792   with dynamicmap_memoization(self.callback, self.streams): 
--> 793    retval = self.callback(*args, **kwargs) 
    794   return self._style(retval) 
    795 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/core/spaces.py in __call__(self, *args, **kwargs) 
    519 
    520   try: 
--> 521    ret = self.callable(*args, **kwargs) 
    522   except: 
    523    posstr = ', '.join(['%r' % el for el in inargs]) if inargs else '' 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/util.py in dynamic_operation(*key, **kwargs) 
    101     self.p.kwargs.update(kwargs) 
    102     obj = map_obj[key] if isinstance(map_obj, HoloMap) else map_obj 
--> 103     return self._process(obj, key) 
    104   else: 
    105    def dynamic_operation(*key, **kwargs): 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/util.py in _process(self, element, key) 
    87    kwargs = {k: v for k, v in self.p.kwargs.items() 
    88      if k in self.p.operation.params()} 
---> 89    return self.p.operation.process_element(element, key, **kwargs) 
    90   else: 
    91    return self.p.operation(element, **self.p.kwargs) 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/core/operation.py in process_element(self, element, key, **params) 
    133   """ 
    134   self.p = param.ParamOverrides(self, params) 
--> 135   return self._process(element, key) 
    136 
    137 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/operation/datashader.py in _process(self, element, key) 
    357 
    358  def _process(self, element, key=None): 
--> 359   agg = aggregate._process(self, element, key) 
    360   shaded = shade._process(self, agg, key) 
    361   return shaded 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/operation/datashader.py in _process(self, element, key) 
    226   agg = getattr(cvs, glyph)(data, x, y, self.p.aggregator) 
    227   if agg.ndim == 2: 
--> 228    return self.p.element_type(agg, **params) 
    229   else: 
    230    return NdOverlay({c: self.p.element_type(agg.sel(**{column: c}), 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/geoviews/element/geo.py in __init__(self, data, **kwargs) 
    81   elif crs: 
    82    kwargs['crs'] = crs 
---> 83   super(_Element, self).__init__(data, **kwargs) 
    84 
    85 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/element/raster.py in __init__(self, data, bounds, extents, xdensity, ydensity, **params) 
    242   if bounds is None: 
    243    xvals = self.dimension_values(0, False) 
--> 244    l, r, xdensity, _ = util.bound_range(xvals, xdensity) 
    245    yvals = self.dimension_values(1, False) 
    246    b, t, ydensity, _ = util.bound_range(yvals, ydensity) 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/holoviews/core/util.py in bound_range(vals, density) 
    1373  using significant digits reported by sys.float_info.dig. 
    1374  """ 
-> 1375  low, high = vals.min(), vals.max() 
    1376  invert = False 
    1377  if vals[0] > vals[1]: 

/home/mcamp/anaconda3/envs/py3.6/lib/python3.6/site-packages/numpy/core/_methods.py in _amin(a, axis, out, keepdims) 
    27 
    28 def _amin(a, axis=None, out=None, keepdims=False): 
---> 29  return umr_minimum(a, axis, None, out, keepdims) 
    30 
    31 def _sum(a, axis=None, dtype=None, out=None, keepdims=False): 

ValueError: zero-size array to reduction operation minimum which has no identity 

Out[54]: 
b':DynamicMap []' 

Answer 1

Ich denke, das Problem hier ist zweifach, vor allem da die Koordinaten Längen- und Breitengrade und Sie angeben, xsampling/ysampling-Werte von 50 Das datengetastete Bild endet mit einer winzigen oder Null-Form, die diesen Fehler verursacht. Mein Vorschlag wäre, zuerst die Koordinaten zu Google Mercator zu werfen. In Zukunft this PR lassen Sie dies so sehr einfach tun, indem Aufruf:

import cartopy.crs as ccrs 
projected = gv.operation.project(points, projection=ccrs.GOOGLE_MERCATOR) 
... 

dies nun manuell tun Sie das cartopy Projektion direkt verwenden können:

coords = ccrs.GOOGLE_MERCATOR.transform_points(ccrs.PlateCarree(), lons, lats) 
projected = gv.Points(coords, crs=ccrs.GOOGLE_MERCATOR) 
...