Axis control and formatting in MATLAB - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set the x-axis limits from 0 to 10.

MATLAB

xlim([1]);

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

A(0, 10)

B[0 10]

C{0, 10}

D0:10

Attempts:

3 left

💡 Hint

Common Mistakes

Using parentheses instead of square brackets.

Using curly braces which create a cell array.

Using a colon operator which creates a vector of multiple points.

The xlim function expects a vector with two elements specifying the lower and upper limits of the x-axis. Use square brackets to create this vector.

2fill in blank

medium

Complete the code to set the y-axis scale to logarithmic.

MATLAB

set(gca, '[1]', 'log');

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

AYScale

BYLim

CYDir

DYTick

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'YLim' which sets limits, not scale.

Using 'YDir' which controls direction.

Using 'YTick' which controls tick marks.

The property YScale controls the scale of the y-axis. Setting it to 'log' changes the axis to logarithmic scale.

3fill in blank

hard

Fix the error in the code to set the x-axis ticks at 0, 5, and 10.

MATLAB

set(gca, 'XTick', [1]);

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

A[0 5 10]

B(0, 5, 10)

C{0, 5, 10}

D0:5:10

Attempts:

3 left

💡 Hint

Common Mistakes

Using parentheses or curly braces which are invalid here.

Using colon operator which creates a vector but with different spacing.

The XTick property expects a numeric vector specifying tick positions. Use square brackets to create this vector.

4fill in blank

hard

Fill both blanks to set the x-axis label and its font size.

MATLAB

xlabel('[1]', 'FontSize', [2]);

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

ATime (s)

B12

C14

DAmplitude

Attempts:

3 left

💡 Hint

Common Mistakes

Using a number as the label text.

Using a string instead of a number for font size.

The first argument to xlabel is the label text. The 'FontSize' property sets the font size, which should be a number.

5fill in blank

hard

Fill all three blanks to create a plot, set the y-axis limits, and add a grid.

MATLAB

plot(x, y, '[1]');
ylim([2]);
grid([3]);

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

A'r--'

B[0 100]

C'on'

D'b-'

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect line style strings.

Using parentheses instead of square brackets for limits.

Using 'off' instead of 'on' for grid.

The plot function's third argument is the line style, e.g., 'r--' for red dashed line. The ylim function sets y-axis limits with a vector. The grid function turns the grid on with the string 'on'.

Practice

1. What does the MATLAB command axis([0 10 0 5]) do to a plot?

easy

A. Sets the x-axis limits from 0 to 10 and y-axis limits from 0 to 5

B. Sets the axis color to RGB values [0 10 0 5]

C. Creates a grid with 10 rows and 5 columns

D. Labels the axes with numbers 0, 10, 0, and 5

Solution

1. Step 1: Understand the axis function input

   The axis function with a vector of four numbers sets axis limits: [xmin xmax ymin ymax].

2. Step 2: Apply the given limits

   Here, [0 10 0 5] means x-axis from 0 to 10 and y-axis from 0 to 5.

3. Final Answer:

   Sets the x-axis limits from 0 to 10 and y-axis limits from 0 to 5 -> Option A

4. Quick Check:

   axis([xmin xmax ymin ymax]) = set axis limits [OK]

Hint: Remember axis([xmin xmax ymin ymax]) sets axis limits [OK]

Common Mistakes:

• Confusing axis limits with colors
• Thinking axis sets labels or grid size
• Using axis without four numbers

2. Which of the following is the correct syntax to set the x-axis label to 'Time (s)' in MATLAB?

easy

A. labelx('Time (s)')

B. xlabel('Time (s)')

C. setxlabel('Time (s)')

D. xaxislabel('Time (s)')

Solution

1. Step 1: Recall MATLAB function for x-axis label

   The function to set x-axis label is xlabel with the label text as input.

2. Step 2: Check syntax correctness

   xlabel('Time (s)') correctly sets the label. Other options are invalid function names.

3. Final Answer:

   xlabel('Time (s)') -> Option B

4. Quick Check:

   Use xlabel('text') to label x-axis [OK]

Hint: Use xlabel('text') exactly to label x-axis [OK]

Common Mistakes:

• Using wrong function names like setxlabel
• Forgetting quotes around label text
• Confusing xlabel with axis or title

3. What will be the effect of the following MATLAB code?

plot(1:5, [2 4 6 8 10]);
axis([0 6 0 12]);
xticks([0 2 4 6]);
yticks([0 6 12]);

medium

A. Plot points with x-axis from 0 to 6, y-axis from 0 to 12, x-ticks at 0,2,4,6 and y-ticks at 0,6,12

B. Plot points with default axis limits and ticks

C. Error because xticks and yticks require vectors of length 5

D. Plot with reversed axes limits

Solution

1. Step 1: Analyze axis limits

   axis([0 6 0 12]) sets x-axis from 0 to 6 and y-axis from 0 to 12.

2. Step 2: Analyze tick settings

   xticks([0 2 4 6]) sets x-axis ticks at 0, 2, 4, 6; yticks([0 6 12]) sets y-axis ticks at 0, 6, 12.

3. Final Answer:

   Plot points with x-axis from 0 to 6, y-axis from 0 to 12, x-ticks at 0,2,4,6 and y-ticks at 0,6,12 -> Option A

4. Quick Check:

   axis + xticks + yticks control limits and ticks [OK]

Hint: axis sets limits; xticks/yticks set tick marks [OK]

Common Mistakes:

• Assuming default ticks remain after setting axis
• Thinking xticks/yticks need same length as data
• Confusing axis limits with tick positions

4. Identify the error in this MATLAB code snippet for setting axis limits and fix it:

plot(1:3, [5 10 15])
axis(0 3 0 20)

medium

A. Limits must be strings; use axis('0 3 0 20')

B. axis function does not set limits; use xlim and ylim instead

C. Missing square brackets around limits; should be axis([0 3 0 20])

D. No error; code runs fine

Solution

1. Step 1: Check axis function syntax

   The axis function requires a vector input for limits, enclosed in square brackets.

2. Step 2: Identify missing brackets

   The code uses axis(0 3 0 20) without brackets, causing syntax error.

3. Final Answer:

   Missing square brackets around limits; should be axis([0 3 0 20]) -> Option C

4. Quick Check:

   axis([xmin xmax ymin ymax]) needs brackets [OK]

Hint: Always use square brackets for axis limits [OK]

Common Mistakes:

• Omitting brackets around axis limits
• Using strings instead of numeric vectors
• Confusing axis with xlim or ylim functions

5. You want to create a plot with x-axis from -5 to 5, y-axis from -10 to 10, and custom ticks every 2 units on both axes. Which MATLAB code correctly achieves this?

hard

A. plot(x,y); axis([-5 5 -10 10]); xticks([-5 2 5]); yticks([-10 2 10]);

B. plot(x,y); axis([-5 5 -10 10]); xticks(-5:5); yticks(-10:10);

C. plot(x,y); xlim([-5 5]); ylim([-10 10]); ticks([-5 5], [-10 10]);

D. plot(x,y); axis([-5 5 -10 10]); xticks(-5:2:5); yticks(-10:2:10);

Solution

1. Step 1: Set axis limits correctly

   axis([-5 5 -10 10]) sets x-axis and y-axis limits as required.

2. Step 2: Set ticks every 2 units

   xticks(-5:2:5) creates ticks at -5, -3, -1, 1, 3, 5; similarly for y-axis with yticks(-10:2:10).

3. Step 3: Check other options

   plot(x,y); axis([-5 5 -10 10]); xticks([-5 2 5]); yticks([-10 2 10]); sets ticks incorrectly (missing intermediate values). plot(x,y); xlim([-5 5]); ylim([-10 10]); ticks([-5 5], [-10 10]); uses invalid ticks function. plot(x,y); axis([-5 5 -10 10]); xticks(-5:5); yticks(-10:10); sets ticks every 5 units, not 2.

4. Final Answer:

   plot(x,y); axis([-5 5 -10 10]); xticks(-5:2:5); yticks(-10:2:10); -> Option D

5. Quick Check:

   Use axis for limits and colon operator for ticks [OK]

Hint: Use colon operator for ticks: start:step:end [OK]

Common Mistakes:

• Setting ticks with wrong intervals
• Using non-existent ticks() function
• Confusing axis limits with tick values