Blatt4

// Main.cpp : Diese Datei enthält die Funktion "main". Hier beginnt und endet die Ausführung des Programms.
//

#include <iostream>
#include <string>
#include <cmath>
using namespace std;

/***********************************Aufgabe 2***************************/
/*
convert from lowercase to uppercase
*/
string uppercaseOf(string s) {

    for (int i = 0; i < s.length(); i++)
        if (s[i] >= 'a' && s[i] <= 'z')
            s[i] = s[i] - 32;

    return s;
}
/**********************************************************************/

/********************************Aufgabe 3*****************************/
bool isPalindrome(string s) {

    string text = uppercaseOf(s);
    int left = 0;
    int right = text.length() - 1;

    while (left < right) {

        if (text[left] != text[right]) {
            return false;
        }
        else {
            left++;
            right--;
        }

    }
    return true;

}
/**********************************************************************/

/****************************Aufgabe 5*********************************/
//function
double f(double x) {
    return pow(x, 4.0) - 5* pow(x, 3.0) + 9 * x +3;
    //return  pow(x, 3.0) - 7*pow(x,2.0) + 8*x-3;
}
//estimate the derivative
double deriv(double a, double h) {

    return (f(a + h) - f(a)) / h;
}
/**********************************************************************/

/*****************************Aufgabe 7 *******************************/

double findZeros(double (*f)(double), double x) {
    double newX = x;
    int counter = 0;
    do {
        counter++;
        x = newX;
        cout << "The " << counter << " root is: " << x <<"\n";
        newX = x - f(x) / deriv(x, 0.001);
    } while (abs(f(x)) > 0.0001);

    return x;
}


/**********************************************************************/

/*****************************Aufgabe 9 *******************************/

/**********************************************************************/

/*****************************Aufgabe 10 ******************************/
double calMean(double * arr, int length) {

    double sum = 0.0;

    for (int i = 0; i < length;i++) {
        sum += arr[i];
    }
    return sum / length;
}

// Standardabweichung
double stdDev(double* arr, int length) {

    double mean = calMean(arr, length);
    double stdDeviation = 0.0;

    for (int i = 0; i < length;i++) {
        stdDeviation += pow(arr[i] - mean, 2.0);
    }

    return sqrt(stdDeviation / length);
}
void  readValues(double* arr, int length) {
    double n;

    for (int i = 0; i < length;i++) {
        cout << "\n Enter a number to the array: " << endl;
        cin >> n;
        cout << "\n";
        arr[i] = n;
    }


}
int readLength() {
    int length;
    cout << "\n Enter the number of values in the array: " << endl;
    cin >> length;
    cout << "\n";

    return length;
}
void displayArray(double* arr, int length) {

    for (int i = 0; i < length; i++)
        cout << arr[i] << "\n" << endl;
}

void readAndDisplay() {
    int numberOfValues = readLength();
    double* arr = new double[numberOfValues];
    readValues(arr, numberOfValues);
    displayArray(arr, numberOfValues);

    cout << "The mean is: " << calMean(arr, numberOfValues)<< "\n\n";
    cout << "The standardDeviation  is: " << stdDev(arr, numberOfValues) << "\n\n";

    delete[] arr;

}
/*********************************************************************/


int main()
{

    //Test: Aaufgabe 2
    string text = "karlsruhe";
    cout << "The text in lowercase: " + text << " is in uppercase : " + uppercaseOf(text) + "\n\n";

    //Test: Aaufgabe 3
    string s1 = "rentner";
    string s2 = "aaba";
    if (isPalindrome(s1))
        cout << s1 + " is Palindrome.\n\n";
    else
        cout << s1 + " is not Palindrome.\n\n";

    //Test: Aaufgabe 7
    cout << findZeros(f, 6) << "\n\n";

    //Test: Aaufgabe 9

    //Test: Aaufgabe 10
    readAndDisplay();
}