Fundamental Questions of Modular Programming in QBASIC for SEE

 

Fundamental question from Modular Programming

1) What is user defined function?  (Specification Grid 2065, SLC supplementary 2066)

Ans: Function which is defined by the user according to their need is called user defined function.

 

2) Write down the difference between function and sub procedure. (SLC supplementary 2065)

Ans: The difference between function and sub procedure are as follows:

Function	Sub procedure
Function return a single value	Sub procedure does not return a value
It can be called by expression or PRINT statement or expression method. eg. b = abc (n)	It is called by CALL statement.

 

3) What is procedure?  List its types. (SLC 2067, SEE 2072)

Ans: A small, logical and manageable functional part of the program is known as procedure. OR,

It is a collection of code to perform an action which does not return a value. Its types are:

 i)  Sub procedure

ii)  Function procedure.   

 

4) Define subroutine.

Ans: Subroutine is a set of program statements that can be called from different places of the main program.

 

5) Write the features of subroutine

Ans: The features of subroutine are as follows:

i) It is called by CALL keyword.

ii) It does not return any value.

iii) It does not consider data type.

iv) It can be recursive.

 

6) What do you mean by procedure?

Ans: Procedure is a collection of code to perform an action which does not return a value. There are two types of procedures:

i) Sub procedures

ii) Function procedures

 

7) Write the importance of subroutine.

Ans: When our program becomes bigger, its code becomes more and more difficult to understand and difficult to find out the bugs, then with the help of subroutine we can mare program simpler and easier.

 

8) What do you mean by recursion?

Ans: A sub program or module that can call itself is called recursion.

 

9) What is variable?

Ans: The entity of number or string whose value are changeable during the program execution time is called variable.

 

10) Write the difference between local and global variable.

Local variable	Global variable
The variable which declared inside the procedures are called local variable.	The variable, which can be accessed from any procedure or module is called global variable
It is not accessible by other functions.	It is accessible by all the other functions

 

11) What is a declare statement? Write its syntax.

Ans: It declares function or sub procedure and invokes arguments data type checking.

Syntax:

DECLARE SUB/FUNCTION name (parameter list)

 

12) Distinguish between shared and common shared.

Shared	Common shared
It gives procedures access to module level variable	It defines global variable that can be shared throughout a program or between chained program.

 

13) Define Function….End function.

Ans: It is a non executable statement that declares the name, the parameters and the code that form the body of a function procedure.

 

14) Write the types of function.

Ans: There are two types of functions. They are as follows.

i) Library or built - in – function

These function are provided by Qbasic software. eg. sqr( ), int( ), left$( ), len( ), mid$( ), date$( ) etc..

ii) User defined functions

Functions, which are defined by the user according to the need are called user defined function.

 

15) Write the advantages of function.

Ans: Following are the advantages of function.

i) There is no chance of duplication.

ii) It can be developed, tasted, debugged, and compiled independently.

iii) Each function is reusable.

iv) Program can be developed in short period of time.

v) Large numbers of programmer can be involved.

 

16)  In how many ways we can pass the arguments in function and procedure?

Ans: We can pass the arguments in function and procedure as follows:

i) By reference

ii) By value

iii)  By enter array into the function

 

17) What do you mean by parameters?

Ans: Parameters are variable that will receive data sent to the procedure.  (Sub procedure and function)                             

OR

Parameters are the pre-defined variable that indicates the input given to the sub-procedure.

 

18) Define arguments.

Ans: Arguments are the actual values, we pass to the sub-procedure.

 

19) Difference between actual parameters and formal parameters. (SEE 2074)

Ans: The difference between actual parameters and formal parameters are as here under:

Actual parameter	Formal parameter
The parameters listed in a function call are called the actual parameters.	The parameters included in function declarations are called formal parameters.

 

20)  What is loop?   (SLC 2068, Supp 2070, SEE 2073)

Ans: Repetition of statements for number of times on the basis of given condition is known as loop.

 

21) What is meant by mode of data file? (SLC 2069)

Ans: Mode of data file means the file to be opened in specific access mode such as reading and writing (Output, Append and Output)

 

22) What is a variable?  (SLC 2070)

Ans: Variable is a location in the memory, contents of which can be changed during the execution of  program.

 

23)  What is a constant?

Ans: The entity (data or value) which cannot be changed during the program execution is called constant.

 

24) What is an operator?

Ans: An operator is a symbol or sign used to indicate a specific operation between the operands in a program.

 

25) Define statement.

Ans: A statement is a set of instructions written using keywords or commands of programming  language.

 

26)       Write the difference between Argument and parameter.

Argument	Parameter
Arguments are values that are sent to the procedure.	These are variables that will receive data sent to the procedure.

 

27) Write down the function of DECLARE statement.

Ans: The function of DECLARE statement is to declare procedure such as FUNCTION or SUB in modular programming.

 

28) Define logical operators. (SEE 2075)

Ans: Logical operators are symbols, which are used to combine two or more logical or relational expressions and return a single ‘true’ or ‘false’.

 

29) Write the difference between library functions and user define functions

Library Functions	User defined functions
Library functions are built it or predefined function of QBASIC	User defined functions are defined or declared by the user.
These types of functions are common for all the users.	These types of function are declared by individual user on the basis of requirement.
Example:  LEN, LEFT$, DATE$	FUNCTION cube(a)