Psst! Check what courses we have in our offer, and get them all here to save $727. Act fast–this deal is available only 3/14–3/21. Creating data frames Feature engineering Summary ## Instruction Perfect! Of course, most of the time you'll create new columns using information from other columns in a data frame. For example, the avg_price column currently represents average housing prices in Euros. Let's create an additional column called avg_price_usd that will represent average housing prices in dollars. We'll use existing columns to calculate this price: avg_price (which is the average price in Euros), and conversion_rate (which equals 1.20). Here's the expression: quarter_prices$avg_price_usd <- quarter_prices$avg_price * quarter_prices$conversion_rate

This expression will create a vector with average price converted to USD and it will assign this vector to a new column avg_price_usd in the quarter_prices data frame.

period avg_price conversion_rate avg_price_usd
Q1 2017 170195 1.20 204234
Q2 2017 173937 1.20 208724
Q3 2017 177938 1.20 213526

## Exercise

Chris would like to know the price per square meter for each property that is on sale in Cibaly. The price per square meter for a property can be calculated with the following formula:

 price / living_area

Use the price and living_area columns from the houses data frame to calculate the price per square meter for each property. Store the results in a column named price_per_sq_meter.