⯈Algorithm and its Characteristics
⯈Elementary Problems
- Addition of two numbers
- Calculate area and circumference of circle
- Calculate area of triangle
- Calculate simple interest
- Calculate slope and distance between two points
- Convert length in feet to inches
- Weighted score in exam
- Convert temperature in degree Celsius to Fahrenheit
- Swap two numbers
- Swap two numbers without using extra variable
- Overview of C Programming Language
- Getting started with C Programming Language
- Keywords
- Identifiers
- Constants
- Operators
- Expression Evaluation
- Mathematical expression to C equivalent expressions
- Datatypes
- Variables
- Integer representation in C
- Character representation in C
- Type conversion in C
- sizeof operator
- Comments
- Mathematical Functions
- input output statements
- width specifiers in C
- structure of a C program
- header files
- Compilation process of a C program
- Types of initializations.
⯈Basic C Programs
- C program to add two numbers
- C program to find area and circumference of circle
- C program to swap two numbers
- C program to swap two numbers without using extra variable
- C program to swap two numbers using bitwise XOR
- C program to convert temperature in Celsius to Fahrenheit
- C program to calculate gross salary of an employee
- C program to count number of digits in a positive integer
- C program to count number of digits in binary representation
- C program to count number of digits in base ‘K’
- C program to convert kilometer to meter, feet, inches and centimeters
- C program to find first and last digit of a number
- C program to find minimum number of currency denominations
- C program to convert cartesian coordinates to polar coordinates
- C program to find distance between two places on earth in nautical miles
- C program to find slope and distance between two points
- C program to add 1 to the number using ‘+’ operator
- C program to find maximum of two numbers using ternary operator
- C program to find maximum of three numbers using ternary operator
- C program to find kth bit of a number
- C program to find last four bits of a byte
Mathematical functions in C
All the mathematical functions are available in header file called as “math.h”. These mathematical functions are used to preform mathematical operations in the program. All the mathematical functions take input as a double number and gives answer in form of double number.
To use these mathematical functions, we need to include math.h in our program.
We will discuss the following functions:
sqrt pow log log10 log2 sin cos tan asin acos atan floor ceil fmod abs fabs
If you want you may skip the detailed explanation and directly goto summary part.
You may watch the video at the end of this page.
Syntax:
#include<math.h>
Some of commonly used mathematical functions
1. sqrt
- This function finds the square root of a positive real number.
- Prototype:
- double sqrt(double);
Example 1:
double a = sqrt(9);
a = 3.00
Example 2:
double a = sqrt(2);
a = 1.414214
Example 3:
double a = sqrt(-2);
output: -nan (not a number)
2. pow
- This function finds the power of base to exponent.
- Prototype:
- double pow(double base, double exp);
Example 1:
double y = pow(2, 4); // y=24
y = 16.000
Example 2:
double y = pow(-1, 0.5);
output: nan (not a number)
log
- This function finds the natural logarithm of a number to base – e.
- Prototype:
- double log(double n);
Example 1:
double y = log(10);
y = 2.302585
Example 2:
double y = log(0.6);
y = -0.510826
Example 3:
double y = log(0);
y = -inf (infinity)
Example 4:
double y = log(-1);
y = -nan (not a number)
log10
- It gives log of a number to base – 10.
- Prototype:
- double log10(double);
Example 1:
double y = log10(10);
y = 1.000
log2
- It gives logarithm of a number to base – 2.
- Prototype:
- double log2(double);
Example 1:
double y = log2(4);
y = 2.000
sin
- This function gives sin of an angle in radians.
- Prototype:
- double sin(double angle_in_radians);
Example 1:
double y = sin(3.142/4); (pi/4)
y = 0.707179
cos
- This function gives cos of an angle in radians.
- Prototype:
- double cos(double angle_in_radians);
Example 1:
double y = cos(3.142/4);
y = 0.707035
tan
- This function gives tan of an angle in radians.
- Prototype:
- double tan(double angle_in_radians);
Example 1:
double y = tan(3.142/4);
y = 1.00024
asin
- This function gives arc-sin. (sin-1 )
- Prototype:
- double asin(double);
Example 1:
double y = asin(1.00);
y = 1.570796
Example 2:
double y = asin(2);
y = nan (not a number), Rangle of sin is [-1, 1]
acos
- This function gives arc-cos (cos-1 )
- Prototype:
- double acos(double);
Example 1:
double y = acos(1.00);
y = 0.00
Example 2:
double y = acos(2);
y = nan (not a number)
atan
- This function gives arc-tan (tan-1 )
- Prototype:
- double atan(double);
Example 1:
double y = atan(1);
y = 0.785398
floor
- This function gives the answer as the nearest integer value, less than or equal to given number.
- Prototype:
- double floor(double);
Example 1:
double y = floor (2.3);
y = 2.00
Since the nearest integer value less than or equal to 2.3 is 2
Example 2:
double y = floor (-2.3);
y = -3.00
Since the nearest integer value less than or equal to -2.3 is -3
Example 3:
double y = floor (2);
y = 2.00
Since the nearest integer value less than or equal to 2.0 is 2
ceil
- This function gives answer as the nearest integer value greater than or equal to given number.
- Prototype:
- double ceil(double);
Example 1:
double y = ceil(2.3);
y = 3.00
Since, the nearest integer value greater than or equal to 2.3 is 3
Example 2:
double y = ceil(-2.3);
y = -2.00
Since, the nearest integer value greater than or equal to -2.3 is -2
Example 3:
double y = ceil(2);
y = 2.00
Since, the nearest integer value greater than or equal to 2.0 is 2
fmod
- This function is used to find the remainder for the real numbers.
- ‘%’ operator is used only for integers.
- Prototype:
- double fmod(double numerator, double denominator);
Example 1:
double y = fmod(3.2 , 2);
y = 1.2, The remainder obtained when 3.2 is divided by 2.
Example 2:
double y = fmod(-3.2 , 2);
y = -1.2, The remainder obtained when 3.2 is divided by 2. (Take the sign of the numerator)
Example 3:
double y = fmod(3.2 , -2);
y = 1.2, The remainder obtained when 3.2 is divided by 2. (Take the sign of the numerator)
abs
- This function gives absolute value of the given number.
- Prototype:
- int abs(int);
- This function can only be applied on integers,
Example 1:
int x = abs(-3);
x = 3
Example 2:
int x = abs(3);
x = 3
fabs
- This function gives absolute value of a real number.
- Prototype:
- double fabs(double);
Example 1:
double y = fabs(2.0);
y = 2.0
Example 2:
double y = fabs(-2.3);
y = 2.3
Summary
| Function Name | Purpose | Example | Output |
|---|---|---|---|
sqrt |
Finds square root of a number |
sqrt(4) |
2.00 |
pow |
Finds pow(base, exp) |
pow(3,4) |
81.00 |
log |
Finds log to base e |
log(10) |
2.302585 |
log10 |
Finds log to base 10 |
log10(10) |
1.00 |
log2 |
Finds log to base 2 |
log2(4) |
2.00 |
sin |
Finds sin of angle in radians |
sin(3.142/4) |
0.707179 |
cos |
Finds cos of an angle in radians. |
cos(3.142/4) |
0.707035 |
tan |
Finds tan of an angle in radians |
tan(3.142/4) |
1.0024 |
asin |
Finds sin inverse (arc sin) |
asin(1) |
1.570796 |
acos |
Finds cos inverse (arc-cos) |
acos(1) |
0.00 |
atan |
Finds tan inverse (arc-tan) |
atan(1) |
0.785398 |
floor |
Finds nearest integer less than or equal given value |
floor(-2.3) |
-3.00 |
ceil |
Finds nearest integer greater than or equal given value |
ceil(2.3) |
3.00 |
fmod |
finds remainder for real numbers |
fmod(3.2, 2) |
1.20 |
abs |
Finds absolute value of an integer |
abs(-1) |
1 |
fabs |
Finds absolute value of a real number |
fabs(-1.1) |
1.1 |