Vector vs raster output decision in Matplotlib - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to save the plot as a vector graphic.

Matplotlib

plt.savefig('plot.[1]')

Drag options to blanks, or click blank then click option'

Apng

Bbmp

Cjpg

Dsvg

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing PNG or JPG which are raster formats.

Using BMP which is also raster.

SVG is a vector graphic format, which keeps the image sharp at any size.

2fill in blank

medium

Complete the code to save the plot as a raster image with high resolution.

Matplotlib

plt.savefig('plot.png', dpi=[1])

Drag options to blanks, or click blank then click option'

A1

B300

C10

D50

Attempts:

3 left

💡 Hint

Common Mistakes

Using very low dpi like 1 or 10 which makes images blurry.

Choosing 50 dpi which is low quality.

300 dpi is a common high resolution for raster images, making them clear.

3fill in blank

hard

Fix the error in the code to save a vector graphic with matplotlib.

Matplotlib

plt.savefig('figure.[1]')

Drag options to blanks, or click blank then click option'

Asvg

Bjpeg

Cgif

Dpng

Attempts:

3 left

💡 Hint

Common Mistakes

Using JPEG or GIF which are raster and not vector.

Choosing PNG which is raster.

SVG is a vector format supported by matplotlib for saving vector graphics.

4fill in blank

hard

Fill both blanks to create a plot and save it as a vector graphic.

Matplotlib

plt.plot(x, y)
plt.[1]('output.[2]')

Drag options to blanks, or click blank then click option'

Asavefig

Bshow

Csvg

Dpng

Attempts:

3 left

💡 Hint

Common Mistakes

Using show instead of savefig to save the plot.

Choosing PNG instead of SVG for vector output.

Use savefig to save the plot and svg as the vector file format.

5fill in blank

hard

Fill all three blanks to save a raster image with high resolution and display it.

Matplotlib

plt.plot(data)
plt.savefig('image.[1]', dpi=[2])
plt.[3]()

Drag options to blanks, or click blank then click option'

Asvg

B300

Cshow

Dpng

Attempts:

3 left

💡 Hint

Common Mistakes

Using SVG which is vector instead of PNG for raster.

Not using show() to display the plot.

PNG is a raster format, 300 dpi gives high resolution, and show() displays the plot.

Practice

1. Which type of output should you choose in matplotlib for a chart that needs to stay sharp when zoomed in or printed in large size?

easy

A. Raster output

B. No output is needed

C. Both vector and raster output

D. Vector output

Solution

1. Step 1: Understand output types

   Vector output uses lines and shapes that scale without losing quality, ideal for charts.

2. Step 2: Match output to use case

   Charts need to stay sharp when zoomed or printed large, so vector is best.

3. Final Answer:

   Vector output -> Option D

4. Quick Check:

   Sharp scalable graphics = Vector output [OK]

Hint: Choose vector for sharp, scalable images like charts [OK]

Common Mistakes:

• Choosing raster output for charts
• Thinking both outputs are always needed
• Confusing vector with raster images

2. Which file extension in matplotlib will produce a raster output file?

easy

A. .svg

B. .png

C. .pdf

D. .eps

Solution

1. Step 1: Identify raster file extensions

   Raster images are pixel-based; common extensions include .png, .jpg, .bmp.

2. Step 2: Match extension to output type

   .png is a raster format, while .svg, .pdf, and .eps are vector formats.

3. Final Answer:

   .png -> Option B

4. Quick Check:

   Raster output = .png [OK]

Hint: Raster files often end with .png or .jpg [OK]

Common Mistakes:

• Choosing .svg as raster
• Confusing .pdf as raster
• Not knowing file extension types

3. What will be the output type of the following matplotlib savefig command?

import matplotlib.pyplot as plt
plt.plot([1, 2, 3], [4, 5, 6])
plt.savefig('output.pdf')

medium

A. Raster image file

B. No file saved

C. Vector image file

D. Text file

Solution

1. Step 1: Check file extension in savefig

   The file is saved as 'output.pdf', which is a vector format.

2. Step 2: Understand matplotlib output choice

   Matplotlib chooses vector output for .pdf files automatically.

3. Final Answer:

   Vector image file -> Option C

4. Quick Check:

   PDF extension = Vector output [OK]

Hint: File extension determines vector or raster output [OK]

Common Mistakes:

• Assuming .pdf is raster
• Thinking no file is saved
• Confusing output type with plot type

4. You want to save a detailed photo using matplotlib but accidentally use plt.savefig('photo.svg'). What is the main problem with this?

medium

A. SVG is a vector format and may not handle photo details well

B. SVG files are always corrupted

C. Matplotlib will save a raster image inside SVG

D. No file will be saved

Solution

1. Step 1: Understand SVG format

   SVG is vector-based, best for shapes and lines, not detailed photos.

2. Step 2: Recognize photo detail needs

   Photos have many colors and pixels; vector formats can't represent them well.

3. Final Answer:

   SVG is a vector format and may not handle photo details well -> Option A

4. Quick Check:

   Photo detail needs raster, SVG is vector [OK]

Hint: Use raster formats for photos, not vector like SVG [OK]

Common Mistakes:

• Thinking SVG files are corrupted
• Expecting raster inside SVG
• Assuming no file is saved

5. You have a matplotlib plot with both a detailed photo background and vector line plots on top. Which approach best preserves quality when saving the figure?

hard

A. Save as a raster image like .png to capture photo details

B. Save as a vector image like .pdf to keep lines sharp

C. Save two separate files: photo as raster and lines as vector

D. Save as .svg and expect both photo and lines to be perfect

Solution

1. Step 1: Analyze image components

   The photo background needs raster to keep details; vector lines alone won't capture photo well.

2. Step 2: Choose output that preserves all parts

   Saving as raster (.png) keeps photo details and acceptable line quality.

3. Step 3: Consider alternatives

   Saving separate files is complex; .svg won't handle photo well.

4. Final Answer:

   Save as a raster image like .png to capture photo details -> Option A

5. Quick Check:

   Photo + lines = raster output best [OK]

Hint: For photos with lines, raster (.png) keeps all details [OK]

Common Mistakes:

• Choosing vector only and losing photo quality
• Trying to save both in one vector file
• Ignoring photo detail needs