how to query a dataframe according to a column codition code example

Example 1: slice dataframe pandas based on condition

# To slice pandas dataframe by condition

frioMurteira = data.loc[(data["POM"] == "Murteira") & (data["TMP"] > 7.2), ["DTM","TMP"]]

Example 2: new dataframe based on certain row conditions

# Create variable with TRUE if nationality is USA
american = df['nationality'] == "USA"

# Create variable with TRUE if age is greater than 50
elderly = df['age'] > 50

# Select all cases where nationality is USA and age is greater than 50
df[american & elderly]