C++ Programming Code Examples
C++ > Mathematics Code Examples
Program to Calculate Standard Deviation
/* Program to Calculate Standard Deviation
This program calculates the standard deviation of 10 data using arrays.
This program calculates the standard deviation of a individual series using arrays. Visit this page to learn about Standard Deviation.
To calculate the standard deviation, calculateSD() function is created. The array containing 10 elements is passed to the function and this function calculates the standard deviation and returns it to the main() function. */
#include <iostream>
#include <cmath>
using namespace std;
float calculateSD(float data[]);
int main()
{
int j;
float data[10];
cout << "Enter 10 elements: ";
for(j = 0; j < 10; ++j)
cin >> data[j];
cout << endl << "Standard Deviation = " << calculateSD(data);
return 0;
}
float calculateSD(float data[])
{
float sum = 0.0, mean, standardDeviation = 0.0;
int j;
for(j = 0; j < 10; ++j)
{
sum += data[j];
}
mean = sum/10;
for(j = 0; j < 10; ++j)
standardDeviation += pow(data[j] - mean, 2);
return sqrt(standardDeviation / 10);
}
A program shall contain a global function named main, which is the designated start of the program in hosted environment. main() function is the entry point of any C++ program. It is the point at which execution of program is started. When a C++ program is executed, the execution control goes directly to the main() function. Every C++ program have a main() function.
Consider a situation, when we have two persons with the same name, jhon, in the same class. Whenever we need to differentiate them definitely we would have to use some additional information along with their name, like either the area, if they live in different area or their mother's or father's name, etc. Same situation can arise in your C++ applications. For example, you might be writing some code that has a function called xyz() and there is another library available which is also having same function xyz(). Now the compiler has no way of knowing which version of xyz() function you are referring to within your code.
Compute square root. Returns the square root of x. The sqrt() function in C++ returns the square root of a number. This function is defined in the cmath header file. There are various functions available in the C++ Library to calculate the square root of a number. Most prominently, sqrt is used. It takes double as an argument. The <cmath> header defines two more inbuilt functions for calculating the square root of a number (apart from sqrt) which has an argument of type float and long double. Therefore, all the functions used for calculating square root in C++ are. Mathematically, sqrt(x) = √x.
#include is a way of including a standard or user-defined file in the program and is mostly written at the beginning of any C/C++ program. This directive is read by the preprocessor and orders it to insert the content of a user-defined or system header file into the following program. These files are mainly imported from an outside source into the current program. The process of importing such files that might be system-defined or user-defined is known as File Inclusion. This type of preprocessor directive tells the compiler to include a file in the source code program.
As the name already suggests, these operators help in assigning values to variables. These operators help us in allocating a particular value to the operands. The main simple assignment operator is '='. We have to be sure that both the left and right sides of the operator must have the same data type. We have different levels of operators. Assignment operators are used to assign the value, variable and function to another variable. Assignment operators in C are some of the C Programming Operator, which are useful to assign the values to the declared variables. Let's discuss the various types of the assignment operators such as =, +=, -=, /=, *= and %=. The following table lists the assignment operators supported by the C language:
Arithmetic Operator is used to performing mathematical operations such as addition, subtraction, multiplication, division, modulus, etc., on the given operands. For example: 6 + 3 = 9, 5 - 3 = 2, 3 * 4 = 12, etc. are the examples of arithmetic operators. Let's discuss the different types of Arithmetic Operators in the C programming. Plus Operator is a simple Plus (+) Operator used to add two given operands. We can use Plus Operator with different data types such as integer, float, long, double, enumerated and string type data to add the given operand. The minus operator is denoted by the minus (-) symbol. It is used to return the subtraction of the first number from the second number. The data type of the given number can be different types, such as int, float, double, long double, etc., in the programing language.
An array is defined as the collection of similar type of data items stored at contiguous memory locations. Arrays are the derived data type in C++ programming language which can store the primitive type of data such as int, char, double, float, etc. It also has the capability to store the collection of derived data types, such as pointers, structure, etc. The array is the simplest data structure where each data element can be randomly accessed by using its index number. C++ array is beneficial if you have to store similar elements. For example, if we want to store the marks of a student in 6 subjects, then we don't need to define different variables for the marks in the different subject. Instead of that, we can define an array which can store the marks in each subject at the contiguous memory locations.
Raise to power. The pow() function returns the result of the first argument raised to the power of the second argument. This function is defined in the cmath header file. pow() function is a library function of cmath header, it is used to find the raise to the power, it accepts two arguments and returns the first argument to the power of the second argument.
In computer programming, loops are used to repeat a block of code. For example, when you are displaying number from 1 to 100 you may want set the value of a variable to 1 and display it 100 times, increasing its value by 1 on each loop iteration. When you know exactly how many times you want to loop through a block of code, use the for loop instead of a while loop. A for loop is a repetition control structure that allows you to efficiently write a loop that needs to execute a specific number of times.
The cin object is used to accept input from the standard input device i.e. keyboard. It is defined in the iostream header file. C++ cin statement is the instance of the class istream and is used to read input from the standard input device which is usually a keyboard. The extraction operator(>>) is used along with the object cin for reading inputs. The extraction operator extracts the data from the object cin which is entered using the keyboard. The "c" in cin refers to "character" and "in" means "input". Hence cin means "character input". The cin object is used along with the extraction operator >> in order to receive a stream of characters.
Following C++ program first ask to the user to enter the value of n and then ask to enter the n Number to add them. This program add all n numbers entered. To add n numbers in C++
To find the largest element in an array in C++ programming, enter the array size, enter the array elements. Start finding for the Largest element in the array to "Display the Largest"
