Mapping using Python Script in KNIME

[iCornerstone]

Hi all,

I am trying to do mapping with Python using Python Script in KNIME.

The Node is a 1 input + No output node
The input to the node is a table with 3 columns. Latitude [Double] , Longitude [Double] and Attribute [String]

I wrote the following code.

import knime.scripting.io as knio
import pandas as inData
import folium

# Load the input table into a Pandas DataFrame
inData = knio.input_tables[0].to_pandas()

# Create a greyscale map with a zoom level of 10 centred in location of those lat/longs
m = folium.Map(location=[50.8, -1.1], tiles='Stamen Toner', zoom_start=10)

# Add a marker for each point
for index, row in inData.iterrows():
    lat = row['latitude']
    lon = row['longitude']
    attr = row['attribution']
    # Create a popup message for the marker
    popup = 'Attribution: {}'.format(attr)
    # Add the marker to the map
    folium.Marker([lat, lon], popup=popup).add_to(m)

#    folium.Marker([row['lat'], row['lon']]).add_to(m)

# Output the map
outData = m

So the Node runs fine without any error. However, I don’t see an output image or map or something.

What am I doing wrong?

[steffen_KNIME]

Hi @iCornerstone,

I’m glad that you try it out! Your script does not give the data back to either a port or the view. For the latter, please refer to the docu section of the Python View node to use that node to get a view. If you only want to get an output image, you can add the output image port to both the Python Script node and the Python View node (via the three dots in the node). Note that the output image port currently only supports svg and png (see Accessing Data here).

There are also a lot of examples in the templates sections of both nodes, please have a look at them. I assume that you use KNIME Analytics Platform 4.7

Does that help?

Best regards
Steffen