MATLAB Data Import and Visualization 3

Question 1

Which MATLAB function reads data from a specific sheet of an Excel workbook?

Accepted Answer

readmatrix('file.xlsx','Sheet','Sheet2')

Answer

readmatrix (and readtable/readcell) accept the 'Sheet' name-value pair to specify which worksheet to read from a multi-sheet Excel file.

Question 2

What is the primary difference between 'plot' and 'scatter' in MATLAB?

Accepted Answer

scatter allows per-point color and size control while plot uses uniform line style

Answer

scatter lets you specify individual marker sizes and colors as vectors, making it ideal for visualizing a third or fourth variable through marker attributes.

Question 3

Which function saves a MATLAB figure to a PNG file?

Accepted Answer

All of the above are valid

Answer

All three methods—exportgraphics, saveas, and print—can export a MATLAB figure to PNG, though exportgraphics (R2020a+) offers the most control over resolution and tight bounding boxes.

Question 4

What does 'tiledlayout(2,3)' do in MATLAB?

Accepted Answer

Creates a 2-row by 3-column grid of axes tiles in the current figure

Answer

tiledlayout (R2019b+) creates a layout manager for arranging multiple axes in a figure; 'nexttile' then places each axes in the next available cell.

Question 5

When using 'fread' to read binary data, what does the 'precision' argument control?

Accepted Answer

The data type of each value read from the file

Answer

The precision argument in fread specifies the data type (e.g., 'int16', 'float32', 'uint8') of each element to be read from the binary file.

MATLAB - MATLAB Technical Computing Practice Test

MATLAB - MATLAB Technical Computing Practice Test

MATLAB Data Import and Visualization 3