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Leer Changing the Data Type | Brief Introduction
Data Preprocessing
course content

Cursusinhoud

Data Preprocessing

Data Preprocessing

1. Brief Introduction
2. Processing Quantitative Data
3. Processing Categorical Data
4. Time Series Data Processing
5. Feature Engineering
6. Moving on to Tasks

book
Changing the Data Type

You already know how to change the data type from string to number, for example. But let's take a closer look at this small but important task.

Let's start by changing the data type from string to datetime. Most often, you will need this to work with time series. You can perform this operation using the .to_datetime() method:

python

To convert a string to a bool - use the .map() method on the column whose values you want to change:

python

For example, if you have a price column that looks like "$198,800" and you want to turn it into a float - you should create custom transformation functions:

12345678910111213
import pandas as pd import re # Create simple dataset df = pd.DataFrame(data={'Price':['$4,122.94', '$1,002.3']}) # Create a custom function to transform data # x - value from column def price2int(x): return float(re.sub(r'[\$\,]', '', x)) # Use custom transformation on a column df['Price'] = df['Price'].apply(price2int)
copy
Taak

Swipe to start coding

Read the sales_data_types.csv dataset and change the data type in the Active column from str to bool.

Oplossing

Switch to desktopSchakel over naar desktop voor praktijkervaringGa verder vanaf waar je bent met een van de onderstaande opties
Was alles duidelijk?

Hoe kunnen we het verbeteren?

Bedankt voor je feedback!

Sectie 1. Hoofdstuk 5
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book
Changing the Data Type

You already know how to change the data type from string to number, for example. But let's take a closer look at this small but important task.

Let's start by changing the data type from string to datetime. Most often, you will need this to work with time series. You can perform this operation using the .to_datetime() method:

python

To convert a string to a bool - use the .map() method on the column whose values you want to change:

python

For example, if you have a price column that looks like "$198,800" and you want to turn it into a float - you should create custom transformation functions:

12345678910111213
import pandas as pd import re # Create simple dataset df = pd.DataFrame(data={'Price':['$4,122.94', '$1,002.3']}) # Create a custom function to transform data # x - value from column def price2int(x): return float(re.sub(r'[\$\,]', '', x)) # Use custom transformation on a column df['Price'] = df['Price'].apply(price2int)
copy
Taak

Swipe to start coding

Read the sales_data_types.csv dataset and change the data type in the Active column from str to bool.

Oplossing

Switch to desktopSchakel over naar desktop voor praktijkervaringGa verder vanaf waar je bent met een van de onderstaande opties
Was alles duidelijk?

Hoe kunnen we het verbeteren?

Bedankt voor je feedback!

Sectie 1. Hoofdstuk 5
Switch to desktopSchakel over naar desktop voor praktijkervaringGa verder vanaf waar je bent met een van de onderstaande opties
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