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Right choice is (a) plot() & stem()

Best EXPLANATION: The pre-defined function in MATLAB to view the graph of a CONTINUOUS and DISCRETE functions is plot() and stem() RESPECTIVELY. There is no such function as cont() or DISC().

The correct choice is (B) Continuous

Best EXPLANATION: Pie plots show the percentage, a category occupies, amongst a DATASET containing several categories. Now, if this dataset is not discrete- it is preferable to USE pie plot since the height of bar plots might be very close to each other to show significant changes. Hence, pie plots REPRESENT continuous data mainly.

Right choice is (a) plot3(x,y,t)

The explanation is: The function to be used is plot3(x,y,t). This will allow him to DRAW a 3d PLOT as asked. The plot will SHOW both the functions ‘F’ and ‘g’ with t on the z-axis.

Correct answer is (c) COMMENT line after function

To explain I would say: When we have MANY FUNCTIONS nested in a primary function, it is a good practice to place comment lines which would help anybody to understand the purpose of the function- making the function more versatile. This comment line introduced right after the function definition is treated as H1 line. All other comment lines after or preceding the function definition won’t be returned as H1 line when the H1 line is sought in MATLAB.

The correct OPTION is (d) The equation has to be solve separately

For explanation: We have to solve the DIFFERENTIATION numerically. To do it in MATLAB, we need to use ode45 after CONVERTING the differential equation to a SYSTEM of first order differential equation.

The correct option is (d) solve[‘equation-1’,‘equation-2’];

The explanation is: To solve equations simultaneously, we NEED to place the equations within the pre-defined MATLAB function ‘solve’ as string arguments within a pair of single INVERTED commas and separated by a COMMA. The function sol can also be used but the syntax within the third bracket is same. So, solve[‘equation-1’,‘equation-2’]; is correct.

Correct option is (a) a=10;b=’pi’;SYMS c; d=[1,2;0;4];

For EXPLANATION I would say: ‘b’ is a character variable, WITHIN inverted commas. ‘a’ is a double variable. ‘c’ is a symbolic object while ‘d’ is a 2*2 MATRIX. The declaration of the VARIABLES is in accordance to the following code:

a=10;b=’pi’;syms c; d=[1,2;0;4];

Correct option is (a) Bar graph

To explain I would SAY: The ANGLE histogram graph plots a histogram circularly. So, VIEWING the FIELD as a CIRCLE, one can easily find the area in the field where the batsman has scored the most runs.

Correct option is (c) Should INCREASE of decrease monotonously

The best explanation: The values of X should be INCREASING monotonously or decreasing monotonously. This is due to the fact that each argument in x refers to the PARTICULAR POSITION of a bar in the bar plot.

Right CHOICE is (a) Name of M-file

The BEST explanation: M-files are text files which can be created in any text editor and it contains the description of a PROGRAM written for a particular purpose.The program description is mainly a self-contained set of statements which comprises of lines of codes or different KINDS of functions. Thus the name of the primary function, where the program description is described, is the M-file.

Correct OPTION is (C) The plot will appear with x axis logarithmically SPACED

For explanation: semilogx() is a pre-defined logarithmic plot function in MATLAB. It will help to bring down the scale of the x axis in out plot to logarithmically spaced values.

Right option is (c) Real TIME user-defined memory allocation

The EXPLANATION: In many softwares, while DECLARING a matrix- the user has to assign a size of the matrix before entering any values to it. But in MATLAB, the user does not need to MENTION any size; mentioning the number of ELEMENTS is enough for MATLAB to determine the size of the matrix required.

The correct option is (C) They show the maximum and MINIMUM value present in an array

For explanation: The COLUMNS ‘Min’ and ‘Max’ show the maximum and minimum values present in a VARIABLE. So, if the variable is an array, the ‘Min’ and ‘Max’ may or may not be same. Here, a is a variable having a single CONSTANT value so they are same.

Correct answer is (a) “ .’ ”

For explanation: ‘ .’ ‘ is used to get the transpose of a MATRIX. ‘ ‘ ‘ is used to get the complex CONJUGATE transpose of a matrix. ‘ ./ ’ is used for the RIGHT DIVISION while the operator, ‘ .\’ is used for LEFT division.

Correct choice is (a) gtext

The explanation: This is a pre-defined FUNCTION in MATLAB. If we WANT to PLACE a text at a position, of our interest, in a graph- we need to USE the gtext command.

The correct option is (a) Variables which retain values between CALLS to the function

For explanation I would say: PERSISTENT variables help to retain the value which has been produced by a sub-function. They are LOCAL to the sub-function but MATLAB reserves permanent storage for them so they might seem like global variables. They are never SHOWN in the workspace so they DIFFER from global variables.

The correct answer is (b) Using str2func

Easy explanation: The function str2cat() returns FLOATING point or decimal expressions for INTEGER values or fractional values. Anonymous FUNCTIONS and inline return decimal values for fractional values but not for integer values. HENCE, str2cat is PREFERABLE.

Correct answer is (a) The FORMER shows the names of the variables being used while the latter shows the details of the variables in the ongoing PROGRAM

For explanation I would say: The function ‘who’ shows the names of the variables used. The function ‘whos’ shows the details of the variables in the ongoing program but it doesn’t SHOW the ATTRIBUTES of the variables.

Right CHOICE is (c) 6x

To explain: A valid variable NAME starts with a letter, followed by letters, DIGITS, or UNDERSCORES. MATLAB is case sensitive, so A and a are not the same VARIABLES, and in 6x digit is followed by a letter which is invalid.

Right answer is (b) MATLAB keeps on generating multiple plots in the same window

The best I can explain: Suppose we PLOT 2 graphs on the same window by USING the hold command. If we don’t stop the IMPLEMENTATION of the hold FUNCTION, MATLAB will keep on generating plots on the same window. So the user won’t get a separate plot if he wants.

Right choice is (d) DECLARE the VARIABLE as global

To ELABORATE: Any global variable, in the primary function, if required to be accessed by a nested function- the variable needs to be declared with the global keyword within the function which requires ACCESS to it. This allows sharing the variable amongst the primary and other functions. If the variable is declared without using the global keyword, the variable MIGHT bring an error to the function.

The correct option is (d) BAR-DIAGRAM

Explanation: Time-series or spatial-series data would COMPRISE of quantitative characters. So they can be represented as a Bar diagram, the height of the bar would demonstrate the QUANTITY of a category.

Correct choice is (b) Produce a symbolic solution

Easy explanation: The SOLVE[] function is an inbuilt function to generate the solutions of ONE or more than one equations. But the result is always produced in symbolic form. So, even if the answer CONTAINS the value of square root of 5, solve[] will return the value as sqrt(sym(5)).

Correct choice is (c) We do it to GET the exact value as MATLAB computes exact values, of numerical expressions, when declared within a string

The BEST I can explain: Variable precision arithmetic in MATLAB is perfected by COMPUTING exact values and exact values are evaluated if the numerical expression is within a string. By not PLACING the pair of inverted COMMAS, we get a floating point approximated value.

The correct answer is (a) True

Easy explanation: We are plotting a PARTICULAR data set for different ENTITIES. The data set may comprise of the same set but each entity is inherently independent from each other. So, we are plotting multiple FUNCTIONS of the same VARIABLES. Hence, the HISTOGRAM is a kind of multiple plots.

Right answer is (a) Polar PLOT

The best I can explain: MATLAB GENERATES a polar plot to REPRESENT the polar co-ordinates of a trigonometric function. This is done with the help of the function ‘polar(angle,RADIUS)’. The angle INCREASES in the anti-clockwise direction.

Right choice is (c) Overlapping

To EXPLAIN I would say: Usually, the default value of width is 0.8 for the function ‘bar()’. Now, if we INCREASE bar width to a value more than 1, the bars would OVERLAP on each other- resulting in a bar plot of overlapping bars.

Right option is (b) False

Easiest explanation: It is dependent upon the programmer to choose the variable NAME while establishing a connection between a global and a PERSISTENT variable. Essentially, one MAY choose to keep the variable name same to AVOID CONFUSION in case of multiple sub-functions. But it is not necessary if there are a small number of sub-functions.

The correct choice is (b) The former is collected from the field of the investigation while the latter is collected from a SEPARATE entity

Easiest EXPLANATION: Data collected directly from the field of purposeful investigation is primary data because it is directly used by the one who collects it. If the data, gathered by an agency or a person, is used by a different agency or person for some PURPOSE- there is no direct link between the data and the person REQUIRING it. Thus this is secondary data.

Correct choice is (b) Histogram does not have negative VALUES while stem may have negative values

To elaborate: Histograms are USED to see the frequency distribution of a variable to show the frequency of a CLASS over any interval. So, naturally, a variable cannot repeat with a negative frequency. Stem plot only RELATES the two arguments it gets in terms of their projected values. So stem() can have negative values.

Right choice is (a) Workspace window

The explanation: The workspace window constantly gets updated with inclusion of any variable in the program. It SHOWS the Value, Size, Bytes, CLASS and many other attributes of the variables used. Hence it is more USEFUL than the WHOS FUNCTION.

Right ANSWER is (a) True

The BEST explanation: MATLAB is very SENSITIVE to the nature of INPUTS defined for a particular command. If the input to a command has to be an integer but we give a character input, it’ll give an error.