Folium: Folium map not rendering when Marker 'popup' specified?

[Per48edjes]

_Apologies, in advance, if this not the most appropriate place for this question (as this might be a Jupyter Notebook issue)!_

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Issue

I cannot get Folium to render a map when the 'popup' parameter for Marker objects are specified via list indexing (where the list contains strings). What's confusing is that it works fine if the Marker 'popup' is a static string!

Example: Working code

This code works (i.e., a viewable map is rendered) in a Jupyter notebook cell:

# Imports dependency used to drop markers onto a map
import folium

# Isolating "northing" and "easting" information with labels for each point
locationlist = df_nearme[["Latitude","Longitude"]].values.tolist()
labels = df_nearme["Cafe Name"].values.tolist()

# Create map and drop points onto it
m = folium.Map(location=[lat_home, long_home], zoom_start=14)
for point in range(len(locationlist)):
    folium.Marker(locationlist[point]).add_to(m)

m

So does this code:

# Imports dependency used to drop markers onto a map
import folium

# Isolating "northing" and "easting" information with labels for each point
locationlist = df_nearme[["Latitude","Longitude"]].values.tolist()
labels = df_nearme["Cafe Name"].values.tolist()

# Create map and drop points onto it
m = folium.Map(location=[lat_home, long_home], zoom_start=14)
for point in range(len(locationlist)):
    folium.Marker(locationlist[point], popup='abc123').add_to(m)

m

Example: Not working code

BUT this code does _not_ render a viewable map (no error is thrown, but I just get a blank, white box):

# Imports dependency used to drop markers onto a map
import folium

# Isolating "northing" and "easting" information with labels for each point
locationlist = df_nearme[["Latitude","Longitude"]].values.tolist()
labels = df_nearme["Cafe Name"].values.tolist()

# Create map and drop points onto it
m = folium.Map(location=[lat_home, long_home], zoom_start=14)
for point in range(len(locationlist)):
    folium.Marker(locationlist[point], popup=labels[point]).add_to(m)

m

As I mentioned before, I suspect this has something to do with Jupyter Notebook, but I'm not entirely sure and figured I'd ask to see if anyone else has run into this issue.

Thanks!

[ocefpaf]

@Per48edjes can you create a sscce with the data so I can try to reproduce?

[Per48edjes]

Hmmmm, not sure how to do that given I'm writing df_near_me from a database query. Here's a sample of the data (in tabular form) that you can load into a Pandas DataFrame with the same name (and then run the code above).

# Import Pandas
import pandas as pd

# Data in JSON string format
data = '{"id":{"0":411083201,"1":418513660,"2":528057543,"3":586713622,"4":647656728,"5":647656785,"6":1493456455,"7":1493456487,"8":2005894602,"9":2095344770,"10":2187987262,"11":2411692096,"12":2411698457,"13":2474058013,"14":2474058022,"15":2881830804,"16":2895323815,"17":2895323816,"18":2983919102,"19":3321734312,"20":3641568148,"21":4010355532,"22":4030622426,"23":4037746568,"24":4055719117,"25":4259001279,"26":4340535594,"27":4625994189,"28":4666687025},"Latitude":{"0":37.7673162,"1":37.7645003,"2":37.7682118,"3":37.7648492,"4":37.771672,"5":37.7721693,"6":37.7763591,"7":37.777046,"8":37.7690716,"9":37.766319,"10":37.7664253,"11":37.7770377,"12":37.7763106,"13":37.7739857,"14":37.774748,"15":37.775488,"16":37.7752166,"17":37.7759142,"18":37.7744588,"19":37.7760172,"20":37.7762395,"21":37.765011,"22":37.769195,"23":37.7750452,"24":37.7726713,"25":37.7717782,"26":37.7745253,"27":37.7768943,"28":37.7752822},"Longitude":{"0":-122.4219479,"1":-122.4216812,"2":-122.4223857,"3":-122.4320119,"4":-122.4331366,"5":-122.4307254,"6":-122.4180877,"7":-122.4172737,"8":-122.4277243,"9":-122.417422,"10":-122.4290387,"11":-122.4175698,"12":-122.4232558,"13":-122.424226,"14":-122.4226877,"15":-122.4159,"16":-122.4195185,"17":-122.4191912,"18":-122.4205881,"19":-122.4314951,"20":-122.4168763,"21":-122.4226685,"22":-122.4315398,"23":-122.4210561,"24":-122.4220741,"25":-122.4167145,"26":-122.4306476,"27":-122.4245402,"28":-122.4161381},"Cafe Name":{"0":"Four Barrel Coffee","1":"Muddy Waters","2":"Carlin\'s Cafe","3":"Peet\'s Coffee & Tea","4":"Nectar","5":"Cafe International","6":"Ma\'velous","7":"Starbucks","8":"Starbucks","9":"Flying Pig Bistro","10":"Church Street Cafe","11":"Anderson Bakery","12":"Blue Bottle Coffee","13":"mercury cafe","14":"gourmet and more","15":"Cumaica","16":"All Star Cafe","17":"Boston Cafe","18":"Javalencia Cafe","19":"Alamo Square Cafe","20":"Blue Bottle Coffee","21":"Stanza","22":"Duboce Park Cafe","23":"Eden Cafe","24":"Delessio Market & Bakery","25":"Gaslamp Cafe","26":"The Center SF Tea House","27":"Cafe la Vie","28":"Peet\'s Coffee"},"Street":{"0":"Valencia Street","1":"Valencia Street","2":"Valencia Street","3":"Market Street","4":"Haight Street","5":"Haight Street","6":"Market Street","7":"Market Street","8":"Market Street","9":"South Van Ness Avenue","10":null,"11":null,"12":null,"13":"Octavia Street","14":null,"15":"Mission Street","16":"Market Street","17":"Van Ness Avenue","18":"Market Street","19":null,"20":"Market Street","21":null,"22":"Sanchez Street","23":"Franklin Street","24":"Market Street","25":"Howard Street","26":"Fillmore Street","27":"Octavia Street","28":null}}'

# Create dataframe from JSON data
df_nearme = pd.read_json(data)

# Imports dependency used to drop markers onto a map
import folium

# Isolating "northing" and "easting" information with labels for each point
locationlist = df_nearme[["Latitude","Longitude"]].values.tolist()
labels = df_nearme["Cafe Name"].values.tolist()

# Create map and drop points onto it
m = folium.Map(location=[lat_home, long_home], zoom_start=14)
for point in range(len(locationlist)):
    folium.Marker(locationlist[point], popup=labels[point]).add_to(m)

m

(Sorry, I'm pretty green. Thanks for being patient.)

[ocefpaf]

The problem is with the popup text. Latest version of folium takes raw HTML for simplicity, a feature that many wanted for a while, so when your text has ' or &, for example, you need to use parse_html=True, see http://nbviewer.jupyter.org/gist/ocefpaf/d1d612d290f766935d8abe1559523a72

[jpeacock29]

Shouldn't this at least be documented in folium.map.Marker?

[ocefpaf]

Shouldn't this at least be documented in folium.map.Marker?

Sure. Do you fancy sending a PR to fix that?

[jpeacock29]

Sure! #771