Unable to modify color or shape of nodes in graph

[dahrs]

Hi,
I'm new to holoviews, but I've found a way to plot the graph I need from an edge list with weights and all, just like I need it. Now I'm trying to find a way to change the color or shape of the source nodes. But I'm unable to do so because I get a weird error:

Traceback (most recent call last): File "testDatashaderHoloviews.py", line 154, in <module> myGraphTestSpringLayout() File "testDatashaderHoloviews.py", line 133, in myGraphTestSpringLayout style=dict(cmap=['blue', 'red'])) File "/u/alfonsda/anaconda3/lib/python3.6/site-packages/holoviews/core/dimension.py", line 1145, in opts backend_options = Store.options(backend=backend) File "/u/alfonsda/anaconda3/lib/python3.6/site-packages/holoviews/core/options.py", line 1059, in options return cls._options[backend] KeyError: 'matplotlib'
I just don't understand what the problem or if there's an easier way to change a selected group of nodes while uploading it from my edge list. I hope there's a solution because the library is really complete and well made.
Here is my code:
`

def myGraphTestSpringLayout():

g = nx.read_edgelist("./myGraphEdgeList.tsv", delimiter='\t', nodetype=str, data=(('weight',float), ('color',str)))

padding = dict(x=(-1.2, 1.2), y=(-1.2, 1.2))

myGraph = hv.Graph.from_networkx(g, nx.spring_layout, nodes=None, weight='weight')

myGraph.opts(plot=dict(color_index='Type', edge_color_index='Weight'),
                              style=dict(cmap=['blue', 'red']))

hv.renderer('bokeh').save(myGraph,'out')`

Thanks in advance,

[philippjfr]

@dahrs It looks like you have to load the bokeh extension before you start defining options. You can either declare the extension at the top:

hv.extension('bokeh')

or move the renderer declaration to the top:

renderer = hv.renderer('bokeh')

Additionally it seems like you are trying to extract the node edge attributes, something that isn't supported currently but will be once #2714 is merged.