Environment and Syntax Flashcards
7 cards from real MATLAB practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Environment and Syntax flashcards as text
What is the effect of using `global x` inside a MATLAB function?
Answer: Shares `x` across the base workspace and all functions that declare it global
Declaring a variable `global` allows multiple functions and the base workspace to share the same instance of that variable.
Which MATLAB command saves all current workspace variables to a `.mat` file named `data.mat`?
Answer: save('data.mat')
`save('data.mat')` writes all workspace variables to a binary `.mat` file, which can later be restored with `load`.
What does `nargin` return inside a MATLAB function?
Answer: The actual number of input arguments passed by the caller
`nargin` returns the count of input arguments that were actually provided when the function was called, enabling optional-argument patterns.
In MATLAB, what does the `end` keyword represent when used as an array index?
Answer: The last valid index of that dimension
When used inside indexing parentheses, `end` automatically resolves to the last index of the relevant array dimension.
Which of the following correctly creates a row vector of integers from 1 to 10 with a step of 2?
Answer: 1:2:10
The colon operator `start:step:end` generates a vector; `1:2:10` produces [1 3 5 7 9].
What is the result of `isinf(1/0)` in MATLAB?
Answer: true (1)
MATLAB evaluates `1/0` as `Inf` without error, and `isinf(Inf)` returns logical 1.
What does the `persistent` keyword do in a MATLAB function?
Answer: Preserves the variable's value between calls to the function
A `persistent` variable retains its value between successive calls to the same function, similar to a static local variable in C.