Category: Python Answers

Sometimes, we want to remove unwanted parts from strings in a column with Python Pandas.

In this article, we’ll look at how to remove unwanted parts from strings in a column with Python Pandas.

How to remove unwanted parts from strings in a column with Python Pandas?

To remove unwanted parts from strings in a column with Python Pandas, we can use the lstrip and rstrip methods.

For instance, we write

data['result'] = data['result'].map(lambda x: x.lstrip('+-').rstrip('aAbBcC'))

to call map on the values in the result column.

We call it with a lambda function that calls lstrip to remove the characters listed on the left end of the string.

Likewise, we call rstrip to remove the characters listed in the right side of the string.

Conclusion

To remove unwanted parts from strings in a column with Python Pandas, we can use the lstrip and rstrip methods.

Sometimes, we want to fix pip install mysql-python fails with EnvironmentError: mysql_config not found.

In this article, we’ll look at how to fix pip install mysql-python fails with EnvironmentError: mysql_config not found.

How to fix pip install mysql-python fails with EnvironmentError: mysql_config not found?

To fix pip install mysql-python fails with EnvironmentError: mysql_config not found, we install the default-libmysqlclient-dev package.

To install the package in Debian or Ubuntu based Linux distros, we run

sudo apt install default-libmysqlclient-dev

Conclusion

To fix pip install mysql-python fails with EnvironmentError: mysql_config not found, we install the default-libmysqlclient-dev package.

Sometimes, we want to find an item in list with Python.

In this article, we’ll look at how to find an item in list with Python.

How to find an item in list with Python?

To find an item in list with Python, we can use the filter function.

For instance, we write

matches = filter(fulfills_some_condition, lst)

to call filter with the fulfills_some_condition function and the lst list.

The fulfills_some_condition function takes the lst item we check the filter condition for as a parameter and returns the condition of the item that matches the filter.

filter returns an iterable that has the items that matches the filter condition.

Conclusion

To find an item in list with Python, we can use the filter function.

Sometimes, we want to change the x axis in matplotlib so there is no white space with Python.

In this article, we’ll look at how to change the x axis in matplotlib so there is no white space with Python.

How to change the x axis in matplotlib so there is no white space with Python?

To change the x axis in matplotlib so there is no white space with Python, we can call the margins method.

For instance, we write

import seaborn as sns
import matplotlib.pyplot as plt

tips = sns.load_dataset('tips')

fig, (ax) = plt.subplots(1, 1, figsize=(10, 4))
tips.plot(ax=ax, title='no margins')
ax.margins(x=0)

to call subplots to create the subplots.

Then we call plot with the ax plot to plot it.

Next, we call ax.margins with the x argument set to 0 to remove the margins from the x-axis.

Conclusion

To change the x axis in matplotlib so there is no white space with Python, we can call the margins method.

Sometimes, we want to parse dates with -0400 time zone string in Python.

In this article, we’ll look at how to parse dates with -0400 time zone string in Python.

How to parse dates with -0400 time zone string in Python?

To parse dates with -0400 time zone string in Python, we use the dateutil library.

To install it, we run

pip install python-dateutil

Then we use it by writing

from dateutil.parser import parse
d = parse('2022/05/13 19:19:30 -0400')

to call parse with the datetime string with the time zone to return a datetime object with the time zone offset set.

Conclusion

To parse dates with -0400 time zone string in Python, we use the dateutil library.