Chapter - 9 Review of Library Function

A function in QBASIC is a readymade small program or user made small program that can perform a specific task. The function manipulates the data passes to it and returns either a string  or a numeric value.  QBASIC supports two different kinds of functions.

i. User Defined Function

ii. Library Function

User Defined function is created by a user using function procedure to perform certain task which can’t perform by using library functions.

Library function is also known as Built-In function or Routine function. A library function in QBASIC may be string function or numeric function. A string library function can manipulate either string or numeric data and returns a string value. A function name having dollar sign ($) is string function. LEFT$(), Right$(), CHR$(), STR$( ), UCASE$( ), DATE$ ( ), MID$(), DATE$(), TIME$(), SPACE$(), LTRIM$(), RTRIM$(), INPUT$(), etc. are some example string functions.   A numeric function can manipulate either string or numeric data and returns a numeric value. A numeric library function name has no type declaration sign. CINT(), SQR(), ASC(), VAL(), LEN (), SGN( ),ABS( ), SIN( ), TAN( ), COS() etc. are some example of numeric library functions.

REM converts uppercase letters of a word in lowercase and vice versa.

CLS

INPUT “Enter a word”; W$

FOR k = 1 TO LEN (W$)

           E$= MID$(W$, k, 1)

           IF E$=UCASE$(E$) THEN

                      New$ =New$+ LCASE$(E$)

           ELSE

                      New$ =New$+ UCASE$(E$)

           END IF

NEXT k

PRINT “New word after converting case is :”; New$

END

REM removes vowels characters from the supplied word.

CLS INPUT “Enter a word:”; W$

FOR j= 1 TO LEN(W$)

           E$= UCASE$(MID$(W$, j, 1)

           IF E$<>”A” AND E$<>”E” AND E$<>”I” AND E$<>”O” AND E$<>”U” THEN

                      New$=New$+E$

           END IF

NEXT j

PRINT “New word is :”; New$

END

REM to check palindrome word.

CLS

INPUT “Enter a word”; W$

FOR j= LEN (W$) TO 1 STEP-1

           rev$= rev$+MID$(W$, j, 1)

NEXT P

IF W$=rev$ THEN

           PRINT “Palindrome word”

ELSE

           PRINT “Not palindrome word”

END IF

END

REM converts Decimal number into Binary Number.

CLS

INPUT “Enter a Decimal number”; N

M = N

DO WHILE N<> 0

           R= N MOD 2

           B$=STR$(R) + B$

           N= INT(N/2)

LOOP

Ans=VAL(B$)

PRINT “Binary equivalent of entered number is “; Ans

END