MathWorks Interview Questions & Reviews

Interview Details – After Career Fair at college, got a mail from them asking to mail resume in case we didn't attend the fair. A few days after mailing resume, got a response asking for suitable time to interview.
This was fairly simple. They asked behavioral questions:
1. Did you ever face a problem in your team and how did you solve it?
2. How do you like working in a team?

More general questions :
3. When are graduating?
4. When would you join after you graduate?

Then they asked me to choose from 4 categories and I chose software programming. It included -

Basic math - discrete math, computation, and algorithm theory
Programming concepts – OOP, data structures, and operating systems.
Programming Languages – Syntax and design questions in C, C++, and Java. MATLAB is optional and may be used to replace one of the other languages.

They scheduled the technical round for the next week.

In this round, they asked :

 What is Big O notation?
 What are local and global variables?
 What is scope of a variable?
 What is the difference between Java Applet and Application?
 typedef
 final
 what is a pointer?
what is class and object
what is a hashtable
Which is faster for searching - linked list or array
what is "define" ? They gave an example and asked how it works
(AUB) ∩ C = ?
What is a null pointer and when is it used?
what should you consider before assigning a pointer?
Is it alright to define all variables as global variables?

Interview Details – It was for about 45-50mins tech phone interview:

Math:
1. Singular matrix?
2. Rank of a matrix and what is its importance?
3. Null space?
4. Inverse of a 2x2 square matrix (For given values)?
5. Given two vectors, what is the angle between them?
6. What is Eigen vector? Importance of Eigen values and vectors.
7. Given acceleration of a body. What is the velocity for a give t value.

Programming concepts:
1. Local and global scope?
2. Recursive functions?
3. Call by value and call by reference?
4. Multicore processors??
5. Difference between break and continue?

Signal processing:
1. Nyquist sampling theorem?
2. Aliasing?
3. Convolution?
4. Difference between FIR and IIR filters?
5. BIBO?
6. Given y(n) = x(n)+C, comments on its linearity, Time variance and Casuality
7. Stability/instability region in discrete time domain?
8. what is PSD and what is it for white noise?
9. Autocorrelation?

Matlab:
1. difference between * and .*?
2. How to plot in Matlab?
3. How to open a file from command window?
4. Differences between script file and function?
5. How to display variable/variables in command window? (whos)
6. How to computer numerical length of an array? (numel)

C Programming:
1. what is #include?
2. Differences between and " " and < > in #include?
3. typedef?
4. malloc?
5. null pointer?

Interview Details – I applied online and after 2 days I got a reply from the hiring manager for the interview availability. Initial round was DETAILED resume discussion. Once that is over, the next round will be technical round.

Negotiation Details – Still left with the on-site interview.

Interview Details – Met the recruiter at a college career fair. Was interested since I was pursuing an graduate degree (PhD) since I think that's what they're mainly looking for to till these positions. Then had a very short phone with an HR person asking some behaviorial questions. I think they were, "Tell me about a time when you worked on a team?." Asked me to pick from a number of interview tracks: Signal Processing, Computer Science, Controls, Math, and Matlab. I realize now that misunderstood the question: what they basically have are one of two tracks - engineering or computer science.

Then had a technical phone interview that lasted about 45 minutes. Didn't go too well since I had selected the Computer Science track although my PhD is in Engineering. The interviewer let me know which section each batch of questions was from. Most of what was asked is below:

General Programming
- What is Object Oriented Programming?
- What are the benefits of inheritence?
- Difference between global and local scope?
- Why would using global variables be a bad practice?
- What are pointers? What is the danger of using a pointer?
- Advantage of a linked list over an array?
- Worse case complexity for searching through a linked list?
- What is multithreading?

C Programming
- Difference between & and * pointers?
- What does #include <stdio.h> mean?
- What is the difference between const x = 100; and #define x 100
- How can you give a data type a new name?
- What is a null pointer? How would it be used?
- What is malloc function?

Matlab
- Difference between a*b and a.*b?
- How to find the transpose?
- Have A,B,C - how would you plot A vs. C and B vs. C on the same plot?
- How to concantenate strings?
- Difference between scripts and functions?
- How to open results.mat?
- How to add a folder to the Matlab directory?
- How to store variables of different data types in the same variable?
- What is a persistence variable?
- What is a .mex file?

Java & Ruby
- Difference between JRE and JDG?
- What is an abstract class?
- A || B means what?
- What happens: A || == B
- Difference b/t rails and ruby?
- What is a rake function?
(would have asked more, but realized that this wasn't my track so we stopped).

Interview Details – Round 1 : Telephonic : Asked me about my GPA and other information related to my resume. Nothing complicated. Scheduled technical round.

Round 2: Questions related to Math, Java, C and C++. Straight forward round. Rapid-fire questions.

Received a call for on-sight (College Day) on the same day.

Interview Details – First technical round.

Interview Details – 1st round :
HR interview. Very basic questions and set up date for 2nd round of technical interview.

2nd round telephone interview:
Maths:
(A ∩ B) U C
summation from 1 to n
summation i=0 to infinity (1/7)^i
summation i=1 to infinity (1/i)
difference between DFA and NFA
pigeonhole principle
four color theorem
add and multiply o(n) and o(n^2)
complexity of matrix multiplication(with an explanation as to why)

C/C++/Java/Programming Concepts:
OOPS definition and concepts
Exception Handling Mechanism
typedef
#define and const (gave a line of code and asked how it works differently)
what is pointer?
malloc and its disadvantage
difference between foo a; and foo();
diff between .equals and ==
operator overloading with an example which operators cant be overloaded
what is final
difference between struct and class
Can we start garbage collection in Java, how
Java m/c dependent or not
JVM m/c dependent or not
abstract class
hashtable explanation
complexities for search operation of linked list, array, binary tree and hashtable. changes when an index is provided

They said they will contact in 2 weeks if they are interested in pursuing for next round! Fingers Crossed! :)

Interview Details – Interview for application support engineer, nothing specific, just first round

Interview Details – You can find most of their questions on glassdoor. They are not difficult and all basic concepts. But you need to explain these concepts very clearly and accurately. Better look up answers in your textbooks.