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DATA SCIENCE PYTHON PLAYGROUND

Data Foundations · A little practice goes a long way.

← Wrangle / Preprocess lessonsTINY TABLES · REAL PYTHON · YOUR PACE
A safe working copy · W01 · 8 MIN

Protect the original

Make changes on a separate working copy.

Exercises within this concept

  1. FollowFollow the techniqueCurrent exercise
  2. ChangeAdapt the workflow
  3. TransferChoose and combine

Understand the idea

Make a separate working table before editing. Assigning another name to df alone still refers to the same object.

Concept sketch: edit clean; original df stays unchangeddfpriceA2B4cleanpriceA4B8df: 2, 4 unchangededit clean; original df stays unchanged
Illustration · not the exercise output

A small example

clean = df.copy() lets you select or sort clean while keeping the original df available.

Follow the code

Apply the idea to the supplied table. Read from top to bottom; the final line displays the result.

clean = df.copy()
clean = clean[["candy", "price"]]
clean

What each part does

clean =
name for the working table
df.copy()
make a separate DataFrame
Other choices for later exercises
clean["price"] =
replace a column in the copy

Your inputs

The editable setup on the right creates df. Run executes the setup and your work from top to bottom.

Candy shop · 6 synthetic rows
candyflavourpriceratingshelf
Gummy Bearfruity1.24.1A
Choco Popchocolate2.14.6B
Mint Bitemint1.53.8A
Berry Loopfruity2.84.4B
Cocoa Cubechocolate3.44.9A
Lemon Dropfruity1.84B

Your task · Follow

  1. Prepare a separate price-list copy named clean from df.
  2. Keep candy and price in that order; leave the original df intact and display clean.
Hint

Make the copy before preparing the handoff.

Reveal solution

One way to do it. Keep any supplied setup in the editor and use this in the Your work section.

clean = df.copy()
clean = clean[["candy", "price"]]
clean
Your task · Follow
  1. Prepare a separate price-list copy named clean from df.
  2. Keep candy and price in that order; leave the original df intact and display clean.

Tab: indent · Shift+Tab: outdent · Esc, then Tab: leave editor

Edit Python. Control or Command plus Enter runs it. Tab indents by four spaces. Shift plus Tab outdents. Press Escape, then Tab or Shift plus Tab to leave the editor.

Each run executes all editor code in a fresh Python session. Display a value by leaving it on the final line.

Python starts when you open a lesson.

Output

Run your code to see what Python returns.