exponents

[JEvans1234]

basically im quite new to programming but i wanted to know how to do exponents. where someone can put in a first number and a second number. the answer would be the first number ^ second number.

i tried writing it as <<firstNumber<<"^"<<secondNumber<<"="<<(firstNumber^secondNumber)<< endl;

but it didnt seem to work... any suggesstions on how to do it???
It will be where:

if ( Op == 7){
cout << "the answer is..."<<

  #include <iostream>

using namespace std;

int main()
{
    {
         double firstNumber = 0.0;
         double secondNumber = 0.0;
         char operation =' ';
         char doAgain=' ';
do
{
     cout << "welcome to Calculator++." << endl;
     cout << "Select Operation" << endl;
     cout << "1. Basic calculations" << endl;
     cout << "2. Trigonometry" << endl;
     cout << "3. Statistics" << endl;

    int M;
    cin >> M;

     if ( M == 1 ){
        cout << "1. Addition" << endl;
        cout << "2. Subtraction" << endl;
        cout << "3. Multiplication" << endl;
        cout << "4. Division" << endl;
        cout << "5. Square a number" << endl;
        cout << "6. Cube a number" <<endl;
        cout << "7. Exponent's ( X^n)" <<endl;
        cout << "8. Squareroot" <<endl;

        {
                cout << "Enter first number" <<endl;
                cin>>firstNumber;
                cout << "Enter operation number (1 to 8)" <<endl;
                cin>>operation;
                cout << "Enter second number (do not enter number for operation 5, 6 and 8)" <<endl;
                cin>>secondNumber;

                int Op;
                cin >> Op;

                if ( Op == 1 ) {
                    cout << "the answer is..."<<firstNumber<<"+"<<secondNumber<<"="<<(firstNumber+secondNumber)<<endl;
                    break;
                }

                if ( Op == 2){
                    cout << "the answer is..."<<firstNumber<<"-"<<secondNumber<<"="<<(firstNumber-secondNumber)<<endl;
                    break;
                }

                if ( Op == 3){
                    cout << "the answer is..."<<firstNumber<<"*"<<secondNumber<<"="<<(firstNumber*secondNumber)<<endl;
                    break;
                }
                if ( Op == 4){
                    cout << "the answer is..."<<firstNumber<<"/"<<secondNumber<<"="<<(firstNumber/secondNumber)<<endl;
                    break;
                }
                if ( Op == 5){
                    cout << "the answer is..."<<firstNumber<<"*"<<firstNumber<<"="<<(firstNumber*firstNumber)<<endl;
                    break;
                }
                if ( Op == 6){
                    cout << "the answer is..."<<firstNumber<<"*"<<firstNumber<<"*"<<firstNumber<<"="<<(firstNumber*firstNumber*firstNumber)<<endl;
                    break;
                }
                if ( Op == 7){
                    cout << "the answer is..."<<

[JLBorges]

Header <cmath>

std::pow() raises a number to the given power
std::sqrt() computes square root
std::cbrt() computes cube root
etc.

http://en.cppreference.com/w/cpp/header/cmath

[JEvans1234]

thank you so much!! :)

[JEvans1234]

im getting an error saying that 'cbrt' is not a member of 'std'

[JLBorges]

std::cbrt() is C++11.

Which compiler (and version) are you using?

[JEvans1234]

im using code blocks 12.11 with GNU GCC compiler but im not sure what version sorry

[JEvans1234]

dont worry i found a tick box that allowed the compiler to notice c++11 language. it works fine now

[JLBorges]

Turn on the compiler option -std=C++11
And while you are at it, turn on these three too: -Wall -Wextra -pedantic-errors

On the menu, Settings => Compiler... (IIRC)

[Chervil]

You may be able to tell the compiler to use the C++11 standard.
From the code::blocks menu, select settings->compiler then click the checkbox for C++11.

Or, instead of using cbrt(), use raise the number to the power 1/3

#include <iostream>
#include <cmath>

    using namespace std;

int main()
{
    double num = 125;
    double a = pow(num,1.0/3.0);
    double b = cbrt(num);

    cout << "num: " << num << "  a: " << a << "  b: " << b << endl;

    return 0;
}