Pandas DataFrame.gt
Pandas DataFrame.gt
The DataFrame.gt
method in pandas is used to compare whether elements of a DataFrame are greater than a specified value or corresponding elements in another DataFrame. The result is a DataFrame of boolean values indicating the comparison results.
Syntax
The syntax for DataFrame.gt
is:
DataFrame.gt(other, axis='columns', level=None)
Here, DataFrame
refers to the pandas DataFrame being compared.
Parameters
Parameter | Description |
---|---|
other | A scalar, sequence, Series, or DataFrame to compare against. |
axis | The axis to align the comparison. 'columns' (default) compares element-wise by column, and 'index' compares by row. |
level | Used for broadcasting in a MultiIndex DataFrame. Specifies the level to align along. |
Returns
A DataFrame of boolean values indicating where the comparison is True
.
Examples
Comparing with a Scalar Value
Compare each element in the DataFrame with a scalar value.
Python Program
import pandas as pd
# Create a DataFrame
data = {
'Name': ['Arjun', 'Ram', 'Priya'],
'Age': [25, 30, 35],
'Salary': [70000, 80000, 90000]
}
df = pd.DataFrame(data)
# Compare elements greater than 30
print("Elements greater than 30:")
result = df.gt(30)
print(result)
Output
Elements greater than 30:
Name Age Salary
0 False False True
1 False False True
2 False True True
Comparing with Another DataFrame
Compare the elements of a DataFrame with those of another DataFrame of the same shape.
Python Program
import pandas as pd
# Create two DataFrames
data1 = {
'Age': [25, 30, 35],
'Salary': [70000, 80000, 90000]
}
data2 = {
'Age': [20, 32, 33],
'Salary': [75000, 75000, 95000]
}
df1 = pd.DataFrame(data1)
df2 = pd.DataFrame(data2)
# Compare elements of the two DataFrames
print("Comparison of df1 > df2:")
result = df1.gt(df2)
print(result)
Output
Comparison of df1 > df2:
Age Salary
0 True False
1 False True
2 True False
Comparing Along Rows (axis='index'
)
Perform element-wise comparison along rows by specifying axis='index'
.
Python Program
import pandas as pd
# Create a DataFrame
data = {
'Name': ['Arjun', 'Ram', 'Priya'],
'Age': [25, 30, 35],
'Salary': [70000, 80000, 90000]
}
df = pd.DataFrame(data)
# Compare each row with a Series
comparison_row = pd.Series([30, 75000], index=['Age', 'Salary'])
print("Comparison along rows:")
result = df[['Age', 'Salary']].gt(comparison_row, axis='index')
print(result)
Output
Comparison along rows:
Age Salary
0 False False
1 True True
2 True True
Handling MultiIndex with level
Use the level
parameter to align comparisons in MultiIndex DataFrames.
Python Program
import pandas as pd
# Create a MultiIndex DataFrame
data = {
'Values': [10, 20, 30, 40]
}
index = pd.MultiIndex.from_tuples(
[('A', 1), ('A', 2), ('B', 1), ('B', 2)],
names=['Group', 'Number']
)
df = pd.DataFrame(data, index=index)
# Compare using level
comparison = pd.Series([15, 35], index=['A', 'B'])
print("Comparison with level alignment:")
result = df.gt(comparison, level='Group')
print(result)
Output
Comparison with level alignment:
Values
Group Number
A 1 False
2 True
B 1 False
2 True
Summary
In this tutorial, we explored the DataFrame.gt
method in pandas. Key points include:
- Using
gt
to compare DataFrame elements with scalar values, Series, or other DataFrames. - Specifying
axis
for alignment along rows or columns. - Handling MultiIndex DataFrames with the
level
parameter.
The DataFrame.gt
method is a powerful tool for element-wise comparison in pandas DataFrames.