MATLAB is a robust programming platform for engineers and scientists as it helps them analyze and design different systems and products. This article will focus on some of the questions you should expect in a Matlab Interview. Let’s explore.
1. What is MATLAB?
MATLAB is one of the high-performing programming platforms that come in handy for numerical computing. It is used by engineers and scientists worldwide to create different systems and products. The platform has calculations, conduct visualization, and programming ability, all powered by an accessible and easy-to-use environment. Other capabilities include algorithm development, scientific and engineering graphic design, modeling, simulation, application development, prototyping, and data analysis.
2. Do You Know Some of the 3-D Visualization Elements in MATLAB?
There are five main 3-D visualization elements in MATLAB that serve different purposes while handling graphics. The surface and mesh plots have plot matrices, color maps, and visualization capabilities. The view control element plays a significant role in controlling the camera viewpoint, setting axis limits, and conducting rotation, aspect ratio, and zooming purposes. The lighting element adds and controls scene lighting, while transparency specifies object transparency. Lastly, volume visualization comes in handy in the volume data grid.
3. Tell Us about the Memory Management Functions in MATLAB
There are six memory management functions on MATLAB. Clear is used to remove variables from memory while pack packs any existing variable to the disk before performing continuous reloads. The save function is used to selectively save variables to the disk while the load function reloads data files stored via the save function. Lastly, the quit parameter helps you exit the platform, including any memory allocated to the system. All these functions there okay huge roles in MATLAB.
4. There are Several Tools in MATLAB. Tell Us More about who, eps, type, pi, and whos.
Who shows all the variables that have already been defined while who shows the sizes, variables, and several important information. The pi function returns the pi equation while the Type function acts as a function name for all the functions in MATLAB’s search path, revealing how the procedures have been written. Lastly, the eps function returns the lowest floating-point number in MATLAB. It is usually used with vectors that have zeros. Adding eps to the vector helps avoid zero problems.
5. How Do You Normally Execute the Source Code in MATLAB?
The source code in MATLAB is generally stored in the (.m) by default. However, when a customer requests that this code be better anchored, there are two main ways of execution. First, we can influence it as a P-to code by converting a significant part of the source code files to a P-code statement, which appears as a text darkened shape. The next step is disseminating the program code in it. Secondly, the source code cab be accumulated in the double solution by complaining it using the MATLAB compiler, this coming up with an independent function.
6. Define Xmath
Xmath is one of the most popular interactive scripting and graphics environments. It is used by Xwindpws workstations and has several improved features benefitting MATLAB users. These include scripting languages with an array of OOP features, debugging tools boasting of GUI features, pointed and clickable color graphics, LNX and C compatible libraries, and a feasible and programmable layer. All these explain why Xmath is important for many MATLAB users. It also comes in handy for interactive mathematics and many scripting functionalities.
7. Mention the Basic Plots and Graphs in MATLAB
MATLAB has a plot function used to create graphical representations of data. It reveals a trend when data is plotted. On the other hand, graphs connect the nodes on MATLAB. Some of the plots and graphs in MATLAB are Errorbar, which reveals error bars along a curve, box for the axis border, line which comes up with a line object, loglog, which is the log to a log-scale plot, semiology, the semilograohic plot and Slim which queries z-axis limits. We also have polar, the plot coordinate split, and plot3, the 3-D line plot. Others include Plotyy, Subplot, and Slim.
8. Do You Know the Loops in MATLAB?
There are three loops in MATLAB, namely the nested, while, and for loop. The while loop, which is similar to several programming languages, sets the initial condition to true. It also places conditional expression into the circle. The nested loop allows MATLAB users to put a loop in another loop in conditional statements. It, therefore, enables the compounding of other statements into compounding loops. Lastly, the for loop in MATLAB allows MATLAB users to write loops efficiently. However, unlike other loops, they have to be executed severally.
9. Mention Some of the Uses of MATLAB
MATLAB can be used for several purposes. Given that it is a high-level programming language, it allows users to manipulate matrices, plot functions, and a range of data, implement algorithms and create different user interfaces. Other uses include data analysis due to its various functionalities, development of algorithms, data analysis, and creation of models and a range of applications. Lastly, MATLAB can interface with several programs written in languages such as C++, Java, C, and Fortran.
10. MATLAB Allows Interpolation and Extrapolation. Can You Define These?
Interpolation in MATLAB refers to taking out function values between data points in a set. Its purpose, therefore, is to add new data points within given sets of data. On the other hand, extrapolation involves finding function values beyond endpoints in a given group. There are two types of interpolation and extrapolation: linear interpolation and extrapolation, and quadratic interpolation and extrapolation. It is also with noting that there are several methods that one can use on MATLAB for interpolation purposes.
11. Mention and Explain about the Operators in MatLab
MATLAB has five different operators: Relational, logical, bitwise, set, and arithmetic. Relational operators are used to compare elements in two arrays. They return logical true or false values that indicate what the relation has. Logical operators show logical values confirming that a condition has been fulfilled, while arithmetic operators have functions permitting multiplication or addition. They return sums for MATLAB users. Set operations in MATLAB compare the constituents of any two sets, thus uncovering anything familiar or different between them. Lastly, bitwise operations change bit patterns of numbers after comparing the various bit fields.
12. What Makes Up MATLAB?
MATLAB comprises five main components: MATLAB language, graphic object handles, Matlab function library, the working environment, and the application program interface. The graphic object handles set and query object properties values while the function library contains all the Matlab functions that permit the design of different systems and processes. The graphical user interface in MATLAB, also known as apps, allows developers to control the software applications by clicking and pointing. Therefore, you don’t have to learn a given language or input commands for an application to run. It is also worth noting that MATLAB allows sharing of apps thanks to this interface.
13. Mention the Features of MATLAB
MATLAB has several features that users find worthy. First, it is a high-performing, 4th generation language that helps perform numerical calculations and develop apps made possible by its interactive environment that supports the design, iterative searching, and finding solutions to problems. It also allows users to integrate programs to other programs written in JAVA, Python, ASP.Net, c, C++, and PHP. Lastly, this programming language has tools to build several applications through its graphical user interface with customizable properties.
14. Explain a Few MATLAB Commands
There are five different sets of commands in MATLAB. The session management commands include ‘help’ which looks up a help topic, whos which lists current variables, quit which stops MATLAB global, which declares variables to be global, clc that clears the command window, exists which confirms the existence of a file/variable, clear which eliminates a variable from memory and who that lits current variables. System commands include path, PWD, delete, diary, dir, CD, date, type, and wklread. There are also input and output commands such as disp, format, fprintf, input, and fscanf. Plotting commands include close, polar, axes, semilogx, semiology, stairs, and stem. Lastly, we have Array, Matrix, and Vector commands such as reshape, size, sum, and eye, which all play distinct critical functions.
15. Mention a Few MATLAB Tools
MATLAB has several tools such as LMI control, robust control, neural networks, system identification, control system, image processing, and LMI control. The LMI control functionality facilitates the design of robust control systems and offers the right tools for LMI based analyses. The robust control tool provides the suitable functions and blocks to analyze and tune control systems. Neural networks, also known as artificial neural networks, are adaptive systems that use interconnecting nodes.
16. What are M and MEX Files?
M-files, also known as script files, are simple text files that allow users to place MATLAB commands. The programming language reads and executes commands similarly to how it does when commands are typed sequentially at the prompt. It is worth noting that these files’ names must end with ‘m’. On the other hand, the MEX file is a function that calls distinct programs such as C and C++ programs. It contains only one function or subroutine and can crash a MATLAB application. Most developers in MATLAB use M-Files.
17. Mention the Image Arithmetic Functions in MATLAB
There are eight different arithmetic functions in MATLAB. Isubtract subtracts a constant from an image while the Immultiply, like the name suggests, multiplies two images or several by a constant. Imlincomb facilitates the linear combination of images while Imdivide divides an image into another or by a constant. The Imcomplement function complements an image, while the Imad function divides two images or adds a constant to an image. Lastly, the Imabsdiff function offers the absolute difference of multiple images. These functions perform whatever is attached to their names.
18. Do You Know about Handle Graphics?
Handle graphics is one of the most critical components of MATLAB, alongside the user graphic interface and many others. It is the only subsystem in Matlab that handles graphics. It has graphics with high-level commands facilitating 2D and 3D data visualization. It also handles image processing and can easily present graphics, just like the name suggests. This component can quickly build customized graphical user interfaces and has low-level commands that allow developers to customize different graphics appearances. It is also with noting that it offers two ways of viewing and changing graphic objects’ properties. You can either do it interactively or through the property editor.
19. Tell Us More about MATLAB Language
MathWorks developed MATLAB to serve as a programming language and a numeric computing environment that allows for the plotting of functions and data, matrix manipulations, algorithm implementation, and creation of user interfaces. It can interface with other programs written in different languages. This language has functions, data structures, control structures, and a number of I/O and OOP features. It also enables developers to create throw-away programs and permits the creation of large and complex application programs. Lastly, it has several vital functions and commands.
20. Do You Know the Graphic System Used in MATLAB?
MATLAB uses handle graphics, which is its primary graphics system. It comes with some high-level and low-level commands that perform a number of functions. High-level commands are charged with data visualization, image processing, and animation creation for two or three-dimensional presentation graphics. This system also allows developers to customize the appearance of graphics fully. One can also build complete graphical user interfaces done by low-level commands. This explains why MATLAB is one of the most powerful development platforms.
21. What are Some of the Program Files that MATLAB Can Write?
MATLAB can write two main program files: scripts and functions. Scripts are files on MATLAB with .m extensions. These files have a series of commands that one intends to execute together. It is worth noting that it doesn’t accept or return any outputs. On the other hand, functions are files that receive both input and output. However, they are similar to functions since they have .m extensions. These functions perform a range of tasks when put together, explaining why they are essential components in MATLAB.
22. Can You Modify the MATLAB Path?
The MATLAB path is easy to modify with the proper knowledge. An example of a MATLAB path is the search path, which is a subset of all file system folders used to identify files in MATLAB efficiently. The simplest way of modifying a MATLAB path is to use the PathTool GUI, which one can easily access in MATLAB. After adding it to RC, one can also use path directories found in the command line and write the current path back to ‘pathdef.m’. However, in cases where there is no permission for such an entry, the path should be written in a different file and then executed from ‘startup.m’.
23. Can You Pre-Allocate a Non-Double Matrix?
Yes. However, one must understand that the pre-allocation of a memory block to hold a non-double matrix is normally memory efficient. When allocating memory blocks for the given matrix, zeros are usually pre-allocated to a matrix. This is done by the function int8(). You can also create a single, double matrix using the Remat function. This function can also easily create an array, making it one of the most critical functions in MATLAB.
24. What Do You Know about the MATLAB API?
The MATLAB Application Program Interface is one of the most critical components of MATLAB. It is a collection of functions/libraries that permits several programmers to write C programs and Fortran interacting with MATLAB. The application program interface typically has the facilities that enable the calling of routines in MATLAB. Some of the available functions can also be used to read and write MATLAB files, as well as call this programming language a computational engine. All in all, this feature allows applications outside MATLAB to work with its data through a neutral interface.
25. Explain GET and SET in MATLAB
These two functions are collectively known as getter and setter functions. The get function normally returns a structure with field names as the object’s property names and values as the current ones of equivalent properties. The information will be displayed on the screen if one does not specify an output argument. On the other hand, the set function facilitates the return of potential values for a given property. While used collectively, the setter functions are used to assign properties, while the getter functions are used to protect the same.
These are some of the common questions in MATLAB interviews that you should look out for. Make sure that you invest in the technical aspect of this field to increase your chances of landing the job. Do not also forget to create an excellent first impression as it is one of the most important determiners of success in interviews. We wish you all the best and hope that whatever we have discussed will help you pass your interview.