I want to find rows that contain a string, like so:
DF[DF.col.str.contains(\"foo\")]
However, this fails because some elements are NaN:
I'm not 100% on why (actually came here to search for the answer), but this also works, and doesn't require replacing all nan values.
import pandas as pd
import numpy as np
df = pd.DataFrame([["foo1"], ["foo2"], ["bar"], [np.nan]], columns=['a'])
newdf = df.loc[df['a'].str.contains('foo') == True]
Works with or without .loc
.
I have no idea why this works, as I understand it when you're indexing with brackets pandas evaluates whatever's inside the bracket as either True
or False
. I can't tell why making the phrase inside the brackets 'extra boolean' has any effect at all.
import folium
import pandas
data= pandas.read_csv("maps.txt")
lat = list(data["latitude"])
lon = list(data["longitude"])
map= folium.Map(location=[31.5204, 74.3587], zoom_start=6, tiles="Mapbox Bright")
fg = folium.FeatureGroup(name="My Map")
for lt, ln in zip(lat, lon):
c1 = fg.add_child(folium.Marker(location=[lt, ln], popup="Hi i am a Country",icon=folium.Icon(color='green')))
child = fg.add_child(folium.Marker(location=[31.5204, 74.5387], popup="Welcome to Lahore", icon= folium.Icon(color='green')))
map.add_child(fg)
map.save("Lahore.html")
Traceback (most recent call last):
File "C:\Users\Ryan\AppData\Local\Programs\Python\Python36-32\check2.py", line 14, in <module>
c1 = fg.add_child(folium.Marker(location=[lt, ln], popup="Hi i am a Country",icon=folium.Icon(color='green')))
File "C:\Users\Ryan\AppData\Local\Programs\Python\Python36-32\lib\site-packages\folium\map.py", line 647, in __init__
self.location = _validate_coordinates(location)
File "C:\Users\Ryan\AppData\Local\Programs\Python\Python36-32\lib\site-packages\folium\utilities.py", line 48, in _validate_coordinates
'got:\n{!r}'.format(coordinates))
ValueError: Location values cannot contain NaNs, got:
[nan, nan]
In addition to the above answers, I would say for columns having no single word name, you may use:-
df[df['Product ID'].str.contains("foo") == True]
Hope this helps.
You can also patern :
DF[DF.col.str.contains(pat = '(foo)', regex = True) ]
There's a flag for that:
In [11]: df = pd.DataFrame([["foo1"], ["foo2"], ["bar"], [np.nan]], columns=['a'])
In [12]: df.a.str.contains("foo")
Out[12]:
0 True
1 True
2 False
3 NaN
Name: a, dtype: object
In [13]: df.a.str.contains("foo", na=False)
Out[13]:
0 True
1 True
2 False
3 False
Name: a, dtype: bool
See the str.replace docs:
na : default NaN, fill value for missing values.
So you can do the following:
In [21]: df.loc[df.a.str.contains("foo", na=False)]
Out[21]:
a
0 foo1
1 foo2
DF[DF.col.str.contains("foo").fillna(False)]