Interpolation (interp1) in MATLAB - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to interpolate the value at x = 2.5 using linear interpolation.

MATLAB

x = [1 2 3 4 5];
y = [10 20 30 40 50];
result = interp1(x, y, [1]);

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

A3.5

B2.5

C1.5

D4.5

Attempts:

3 left

💡 Hint

Common Mistakes

Using a value outside the range of x, which causes NaN result.

Using an x value that is not numeric.

The value 2.5 is between 2 and 3, so interp1 will interpolate at this point.

2fill in blank

medium

Complete the code to use 'nearest' method for interpolation at x = 3.7.

MATLAB

x = [1 2 3 4 5];
y = [10 20 30 40 50];
result = interp1(x, y, 3.7, [1]);

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

A'nearest'

B'linear'

C'spline'

D'pchip'

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'linear' instead of 'nearest' changes the interpolation behavior.

Forgetting the quotes around the method name.

The 'nearest' method picks the nearest data point for interpolation.

3fill in blank

hard

Fix the error in the code to interpolate at x = 6 using extrapolation.

MATLAB

x = [1 2 3 4 5];
y = [10 20 30 40 50];
result = interp1(x, y, 6, 'linear', [1]);

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

A'spline'

B'linear'

C'extrap'

D'nearest'

Attempts:

3 left

💡 Hint

Common Mistakes

Not specifying 'extrap' causes NaN for out-of-range points.

Using 'nearest' or 'linear' without extrapolation option.

To interpolate outside the range of x, use 'extrap' to allow extrapolation.

4fill in blank

hard

Fill both blanks to create a vector of interpolated values at points 1.5 and 4.5 using 'pchip' method.

MATLAB

x = [1 2 3 4 5];
y = [10 20 30 40 50];
xi = [[1] [2]];
result = interp1(x, y, xi, 'pchip');

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

A1.5

B4.5

C2.5

D3.5

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing points outside the x range without extrapolation.

Using points that are not numeric.

The points 1.5 and 4.5 lie between the x values and are used for interpolation.

5fill in blank

hard

Fill all three blanks to interpolate values at points 2, 3.3, and 5 using 'spline' method.

MATLAB

x = [1 2 3 4 5];
y = [10 20 30 40 50];
xi = [[1] [2] [3]];
result = interp1(x, y, xi, 'spline');

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

A2

B3.3

C5

D'spline'

Attempts:

3 left

💡 Hint

Common Mistakes

Using points outside the x range without extrapolation.

Not using the correct method string for interpolation.

The points 2, 3.3, and 5 are used for interpolation with the 'spline' method.