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The CORRECT choice is (a) True

The best explanation: The help command will only show the nature of functions of any command which is already existing in the MATLAB directory. If we WANT to show the PURPOSE of our written function, we have to ADD comments in our m-file and then enter the echo command.

Right answer is (b) She has placed a semicolon at the end of the line which computes the desired values

To explain: If we write a function file, we should not put a semicolon at the line which computes a value. This will LEAD to the PASSING of cursor to the next line after the function is IMPLEMENTED without SHOWING any output. So it was good that the teacher SCOLDED her.

Correct answer is (a) True

For EXPLANATION: A for-loop has a SINGLE INDEX. But it has multiple index-values during successive iterations.

The correct answer is (b) Type EDIT in MATLAB and press Enter

The best explanation: M-files are simple text files containing MATLAB programs. These can be used to run complex programs EASILY. In MATLAB, we can type edit to begin WRITING in Editor/Debugger MODE. Typing debug or M-file won’t do any good.

Correct answer is (a) Simulink

The best I can EXPLAIN: Simulink is a separate PACKAGE which is present in MATLAB. It helps to model and ANALYZE a CONTROL system which makes MATLAB a very powerful tool for simulating dynamic systems.

The CORRECT option is (c) Use the dbcont & return command

Easy explanation: While debugging, the user can choose to insert a set of instruction to change the nature of the already WRITTEN program. To return to CONTINUE EXECUTION, the user can enter either dbcont or the return command.

Correct option is (B) False

To elaborate: The look for command shows the H1 line USED in a function. The look for command will DESCRIBE only inbuilt functions and not user-defined function. The H1 line is comment line just after the function definition so the look for command does not return the function definition.

The correct answer is (a) Ctrl+C

The explanation is: The pause/keyboard COMMAND is used to suspend execution for a CERTAIN time. If we press Ctrl+C, execution will be completely STOPPED. The end command is used to end LOOPS of any KIND.

Right answer is (a) Press Ctrl+C

Best EXPLANATION: If we begin an infinite LOOP, by choice or as a silly mistake, we can TERMINATE the loop manually if we forget to introduce a break STATEMENT as necessary. We can choose to press Ctrl + C and the loop will get terminated at the same INSTANT.

Correct option is (a) True

To EXPLAIN: We can PROVIDE MULTIPLE CONDITIONS to END a while loop. The conditions can be different so we can have multiple decision variables for while loop.

Right OPTION is (B) False

Explanation: In case of nested for-loops or while-loops, the break statement will remove CONTROL only form the loop where it was INVOKED as a command. It won’t come out from the OUTER loop.

Right answer is (a) Include clear all at the BEGINNING of function file

Best EXPLANATION: EVEN though the variables defined within a function are LOCAL variables, they might get affected due to the previous usage. So while execution of the same function, the user might get a different answer. Thus it is ADVISED to include clear all to remove all previous definitions of variables. The command ‘close all’ is used to clear the previously created graphs.

Right answer is (a) A straight line

The best I can explain: The EXPONENTIAL inter-relation will appear as a straight line in a log scale. This is because LOGARITHMIC scale and exponential NATURE follow a linear RELATIONSHIP. If there are no other terms than EXPONENTIALS in the expression, the graph will be a linear one.

Right CHOICE is (a) True

To elaborate: MAT files save data from the workspace. A graph, plotted among different variables, cannot be stored in MATLAB SINCE MAT-files are files USED to STORE values from the workspace.

The correct CHOICE is (d) The program cannot be shown while RUNNING a MEX FILE

Easy explanation: MEX files are not M-files. They are binary files which store the values of variables present in the WORKSPACE. So there is no QUESTION of showing the program of a MAT file.

The CORRECT answer is (B) False

Explanation: MEX files are files WRITTEN in C language. They can be integrated with MATLAB. They won’t work on JAVA.

Right choice is (B) False

The best I can EXPLAIN: While TRYING to compute a value for the LOGARITHM of a negative number, MATLAB will return an imaginary value. We can do problems which need to compute the logarithm of a negative number.

Right choice is (b) False

The best explanation: We can PLOT a DISCRETE and continuous relationship in the same GRAPH. We have to use the hold command and change the scaling of the variables a BIT if at all needed, so that the discrete and continuous relationship LOOKS prominent enough in the same graph. We have to use the hold command efficiently.

The CORRECT OPTION is (d) It shows the COMMANDS and the comments in M-files

For explanation: The ECHO COMMAND is a pre-defined function in MATLAB. If it is present in an m-file, the command will help to show the commands and comments present in the m-file when the m-file is called in the command window.

The CORRECT option is (a) Press Ctrl +c

The explanation is: It may so happen that we want to PAUSE the execution of a set of commands at a certain point. We only need to press Ctrl and C together to pause it. On the other HAND, quit causes the MATLAB software to shut down. Debugging modes are ALSO AVAILABLE in MATLAB.

The correct option is (c) Help returns the entire SET while look for returns specific commands

The best I can explain: The ‘help’ command is used to return all the commands SURROUNDING a particular toolbox name ENTERED ALONG with it. The ‘look for’ command is used to return a particular function or set of functions WHOSE name matches with the keyword entered in along with the ‘look for’ command.

The correct choice is (a) close all

For EXPLANATION I would say: The command close all is a pre-defined function in MATLAB. When it is CALLED, MATLAB will automatically shut down the separate WINDOWS that have been OPENED to view graphs separately. The rest of the options are WRONG.

The correct CHOICE is (c) Allows the user to COMBINE C SOURCE files with MATLAB files

The explanation: MEX files are one of the kinds of file MODES available in MATLAB. They are saved with a .mex extension. These files help in the association of C source files into the programs written in MATLAB.

Right choice is (a) at the top in

The BEST explanation: MENTIONING the global variables at the top of an M-file allows the user to prevent any error RISING to usage of the same variable unconsciously. If we DECLARE it anywhere, it MAY so happen that we would need it at the beginning. Hence- it is plausible to declare it at the top of an M-file.

The correct answer is (a) True

Explanation: The purpose of using loops is to AVOID WRITING the same line multiple times. The same line may be a particular function which computes a certain value. For the SAKE of accuracy, we may run the function multiple times, within a loop.

Right OPTION is (a) .m

The BEST I can EXPLAIN: Script files are a kind of M-file. So to SAVE a script file, it has to saved with a .m extension. On the other hand, .mat extension is for MAT files.

Correct OPTION is (a) loglog

Explanation: There is no command CALLED semilog or log to plot a graph with logarithmic scales. However, we have the loglog function, pre-defined in MATLAB, which allows US to plot a graph of two VARIABLES where both the variables are scaled logarithmically.

Correct answer is (C) %G

The explanation: %g is USED to REPRESENT any number, which has a fixed number of digits or a number with an exponent, with no insignificant zeros. This is present in the MATLAB DIRECTORY only.

The CORRECT option is (a) Use the PAUSE command

To elaborate: The hold off command is necessary to plot MULTIPLE graphs in the same window. Thus multiple 2d graphs or multiple 3d graphs can be drawn on the same window. But the pause command is used to KEEP the plot of 2d graphs and WAIT before generating 3d graphs. The close command closes any existing graphs.

Correct choice is (a) Using the HOLD function

To elaborate: The hold command is a pre-defined function in MATLAB. It ALLOWS the control to remain in the WINDOW where which was generated by MATLAB, the FIRST time we type a command to plot any KIND of graph. Then on we can plot multiple graphs on the same window.

The correct answer is (a) Time of VARIABLE generation

To explain I would say: By right CLICKING on the Workspace header, we will get to KNOW the characteristics of the variables which are stored in the Workspace and what it can display. The time of variable generation is not present in the Workspace. It can only be seen if the variables from the workspace are saved separately USING the command ‘SAVE filename’.

Right option is (a) Use the clear all command at the beginning

To EXPLAIN: The clear all command keeps all the local VARIABLES of the function unaffected i.e. they prevent their VALUES from getting changed due to some previous USAGE of the function. The close all command closes all the graphs the clc command removes the written code.