Here is the syntax that you may use to change strings to uppercase in Pandas DataFrame:
df['column name'].str.upper()
Next, you’ll see the steps to apply the above syntax using a practical example.
Steps to Change Strings to Uppercase in Pandas DataFrame
Step 1: Create a DataFrame
To start, let’s create a simple DataFrame with 5 vegetables (all in lowercase) and their prices:
import pandas as pd
data = {'Vegetables': ['broccoli','carrot','onion','celery','spinach'],
'Price': [2,3,1.5,2.5,1]
}
df = pd.DataFrame(data, columns = ['Vegetables', 'Price'])
print (df)
As you can see, all the 5 vegetables are captured in lowercase:
Vegetables Price
0 broccoli 2.0
1 carrot 3.0
2 onion 1.5
3 celery 2.5
4 spinach 1.0
Step 2: Change the strings to uppercase in Pandas DataFrame
Next, change the strings to uppercase using this template:
df['column name'].str.upper()
For our example, the complete code to change the strings to uppercase is:
import pandas as pd
data = {'Vegetables': ['broccoli','carrot','onion','celery','spinach'],
'Price': [2,3,1.5,2.5,1]
}
df = pd.DataFrame(data, columns = ['Vegetables', 'Price'])
df['Vegetables'] = df['Vegetables'].str.upper()
print (df)
Run the code in Python, and you’ll see that all the 5 vegetables are now converted to uppercase:
Vegetables Price
0 BROCCOLI 2.0
1 CARROT 3.0
2 ONION 1.5
3 CELERY 2.5
4 SPINACH 1.0
What if each value in the DataFrame contains multiple words in lowercase?
For instance, in the DataFrame below, each value under the ‘Vegetables’ column contains multiple words/vegetables in lowercase:
import pandas as pd
data = {'Vegetables': ['broccoli and cauliflower','carrot and cabbage','onion and basil','celery and kale','spinach and lettuce'],
'Price': [4,5.5,3.5,3,4.5]
}
df = pd.DataFrame(data, columns = ['Vegetables', 'Price'])
print (df)
This is how the new DataFrame would look like:
Vegetables Price
0 broccoli and cauliflower 4.0
1 carrot and cabbage 5.5
2 onion and basil 3.5
3 celery and kale 3.0
4 spinach and lettuce 4.5
You can then apply the same logic to change the strings to uppercase:
import pandas as pd
data = {'Vegetables': ['broccoli and cauliflower','carrot and cabbage','onion and basil','celery and kale','spinach and lettuce'],
'Price': [4,5.5,3.5,3,4.5]
}
df = pd.DataFrame(data, columns = ['Vegetables', 'Price'])
df['Vegetables'] = df['Vegetables'].str.upper()
print (df)
Once you run the code, you’ll see that all the vegetables are in uppercase:
Vegetables Price
0 BROCCOLI AND CAULIFLOWER 4.0
1 CARROT AND CABBAGE 5.5
2 ONION AND BASIL 3.5
3 CELERY AND KALE 3.0
4 SPINACH AND LETTUCE 4.5
Capitalize the First Character of Each Word
You can use str.title() to capitalize the first character of each word:
import pandas as pd
data = {'Vegetables': ['broccoli and cauliflower','carrot and cabbage','onion and basil','celery and kale','spinach and lettuce'],
'Price': [4,5.5,3.5,3,4.5]
}
df = pd.DataFrame(data, columns = ['Vegetables', 'Price'])
df['Vegetables'] = df['Vegetables'].str.title()
print (df)
You’ll now see that the first character of each word is now capitalized under the ‘Vegetables’ column:
Vegetables Price
0 Broccoli And Cauliflower 4.0
1 Carrot And Cabbage 5.5
2 Onion And Basil 3.5
3 Celery And Kale 3.0
4 Spinach And Lettuce 4.5
Only Capitalize the First Character of the First Word
Alternatively, you can only capitalize the first character of the first Word (while keeping everything else in lowercase):
import pandas as pd
data = {'Vegetables': ['broccoli and cauliflower','carrot and cabbage','onion and basil','celery and kale','spinach and lettuce'],
'Price': [4,5.5,3.5,3,4.5]
}
df = pd.DataFrame(data, columns = ['Vegetables', 'Price'])
df['Vegetables'] = df['Vegetables'].str.capitalize()
print (df)
Here is the result:
Vegetables Price
0 Broccoli and cauliflower 4.0
1 Carrot and cabbage 5.5
2 Onion and basil 3.5
3 Celery and kale 3.0
4 Spinach and lettuce 4.5
You may refer to the Pandas Documentation to learn more about str.upper().
You may also want to check the following guide for the steps to change strings to lowercase in Pandas DataFrame.