s21_math.c

#include "s21_math.h"

#include <math.h>
#include <stdio.h>

double shift_2pi(long double x);
long double old_s21_atan(double x);

int main() {
    // long double y = -5.55555;
    // printf("%Lf\n", s21_fabs(y));
    // printf("%f\n\n", fabs(y));
    // printf("%f\n", floor(-4.4));
    // printf("%Lf\n", s21_floor(-4.4));
    // printf("%f", exp(1));
    // long long int test = factorial(25);
    // printf("%lld", test);
    double t = s21_PI * 756745.6534643;  // сходится
    t = 5.1945045;                       // сходится
    t = -s21_PI * 756450.5;              // cходится
    t = s21_PI * 756450;                 // cходится
    t = s21_PI * 75645000;               // сходится
    t = s21_PI * 756450000.546;          // сходится
    // t = 100000000;                       // сходится
    // t = 10000000040;  // сходится 10 знаков
    // t = s21_PI_POPOLAM + s21_PI_POPOLAM;
    // t = 10000000001.0;
    // t = 10000000002.0;
    // t = 19099100000;  // не сходится последний знакЪ
    // t = 1000000000100.0;
    // t = 57.739537;
    // t = 57.73932712;
    // t = 2707.543636;
    // t = 2707.543615;
    // t= 2713.02345678;
    // t = 1000000.645646;
    // t = 2707;
    // t = s21_PI/2;
    // t = -s21_PI/2;
    // t = 710;
    // t = 2*s21_PI;
    // t = s21_PI_11;
    // t = s21_PI_10;
    // t = 2707;
    // printf("%Lf\n", s21_sin(t));
    // printf("%f\n", sin(t));
    // printf("%Lf\n", s21_cos(t));
    // printf("%f\n", cos(t));

    // printf("%Lf\n", s21_log(t));
    // printf("%f\n", log(t));
    // printf("%Lf\n", s21_sqrt(t));
    // printf("%f\n", sqrt(t));

    // double pi_d = 314159265358.979323846264338;
    // printf("%.15f\n", pi_d);
    // long double pi_l = 314159265358.979323846264338;
    // printf("%.15Lf\n", pi_l);
    // printf("%.15f\n", s21_PI_9);
    // long double test_exp = s21_exp(t);
    // printf("%f\n", (double)test_exp);
    // printf("%f", exp(t));
    // long double test_sin = s21_sin(t);
    // printf("our sin = %Lf\n", test_sin);
    // printf("origin sin = %f\n", sin(t));
    // printf("pi = %.40f\n", s21_PI);
    // printf("origin pi = %.40f\n", M_PI);
    // printf("1000000*pi = %.40f\n\n", s21_PI * 1000000);
    // printf("%Lf\n", s21_ceil(5.999999999999999999999));
    // printf("%f\n", ceil(5.999999999999999999));
    // printf("%Lf\n", s21_floor(0));
    // printf("%f\n", floor(0));
    // printf("%f\n", sin(0));
    // t = 5 * s21_PI;
    // t = 1.570796;
    // t = s21_PI_POPOLAM;
    // long double test_tan = s21_tan(t);
    // long double orig_tan = tanl(t);
    // printf("tan: %Lf\n", s21_tan(t));
    // printf("orig tan: %Lf\n", tan(t));
    // printf("difference: %.40Lf\n", test_tan - orig_tan);
    // t = 1.570796;
    // t = s21_PI_POPOLAM;
    t = 3;
    double test_exp = s21_exp(t);
    double orig_exp = exp(t);
    printf("exp:      %f\n", test_exp);
    printf("orig exp: %f\n", orig_exp);
    printf("difference: %.40f\n", test_exp - orig_exp);
    // t = -0.567897654;
    // t = -21345;
    // t = 345;
    // t = 0.9;
    // printf("%f\n", asin(t));
    // printf("%Lf\n", s21_asin(t));
    // printf("%f\n", acos(t));
    // printf("%Lf\n", s21_acos(t));
    // t = -1;
    // double n = -501;
    // long double x = powl(t, n);
    // long double y = s21_pow(t, n);
    // printf("original atan:             %.40Lf\t\n", x);
    // printf("s21 atan:                  %.40Lf\n", y);
    // printf("difference origin and new: %.40Lf\t\n", x - y);
    // printf("difference new and old:    %.40lf\t\t\n", y - z);
    // printf("difference origin and old: %.40lf\t\n", x - z);
    // t = 2.56789;
    // t=1000000000.0;
    // t = 0.00001;
    // t = 1;
    // t =
    //
    1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000.0;
    // double or_log = log(t);
    // long double new_log = s21_log(t);
    // printf("original log = %.40f\n", or_log);
    // printf("     new log = %.40Lf\n", new_log);
    // printf("difference origin and old: %.40Lf\t\n", new_log - or_log);
    // t = (float)M_PI_2;
    // t = (float)s21_PI_POPOLAM;
    // t = s21_PI_6;
    // double or_exp = tan(t);
    // long double new_exp = s21_tan(t);
    // printf("original exp = %.40f\n", or_exp);
    // printf("     new exp = %.40Lf\n", new_exp);
    // printf("difference origin and old: %.40Lf\t\n", new_exp - or_exp);
    // t = 10000000000;
    // double or_sin = sin(t);
    // long double new_sin = s21_sin(t);
    // printf("original sin = %.40f\n", or_sin);
    // printf("     new sin = %.40Lf\n", new_sin);
    // printf("difference origin and old: %.40Lf\t\n", new_sin - or_sin);
    // printf("%.40Lf\n", s21_sqrt(2));
    // printf("%.40f\n", sqrt(2));
    return 0;
}
long int s21_abs(int x) {
    if (x < 0) {
        x = x * (-1);
    }
    return x;
}

long double s21_fabs(double x) {
    if (x < 0) {
        x = x * (-1);
    }
    return (long double)x;
}

long double s21_floor(double x) {
    double t = x;
    x = (long double)(int)x;
    if (x < 0 && (int)t - t != 0) x -= 1;
    return x;
}
long double s21_ceil(double x) {
    double t = x;
    x = (long double)(int)x;
    if (x > 0 && (int)t - t != 0) x += 1;
    return x;
}

long double s21_fmod(double x, double y) {
    double res1, res2, res;
    res1 = x / y;
    if (x < 0 && y < 0) {
        res2 = s21_abs(res1);
    } else if (x < 0 || y < 0) {
        res2 = (-1) * s21_abs(res1);
    } else {
        res2 = s21_abs(res1);
    }
    res = x - res2 * y;
    if (y == 0) {
        res = 0 / 0.0;
    }
    return res;
}

long double s21_exp(double x) {
    long double res = 0;
    // if (x > 5) {
    //     res = s21_exp(x-5)*exp(5);
    // }
    if (x < 0) {
        res = 1 / s21_exp((-1) * x);
    } else {
        long double dif = 1;
        long double res2;
        int k = 0;
        while (dif > PREC) {
            double current = 1;
            for (int j = 1; j <= k; ++j) {
                current *= x;
                current /= j;
            }
            res += current;
            if (k > 0) dif = s21_fabs(res - res2);
            res2 = res;
            k++;
        }
    }
    return res;
}

long double s21_sin(double x) {
    int f_minus = 1;
    if (x < 0) {
        f_minus = -1;
        x = (-1) * x;
    }
    x = shift_2pi(x);
    long double res = 0;
    long double dif = 1;
    long double res2;
    int k = 0;
    while (dif > PREC) {
        long double current = 1;
        for (int j = 1; j <= 2 * k + 1; ++j) {
            current *= x;
            current /= (j);
        }
        res += s21_pow(-1, k) * current;
        if (k > 0) dif = s21_fabs(res - res2);
        res2 = res;
        k++;
    }
    return res * f_minus;
}

long double s21_cos(double x) {
    x = shift_2pi(x);
    return s21_sin(s21_PI_POPOLAM - x);
}

long double s21_log(double x) {
    long double res = 0;
    if (x < 0) {
        res = 0 / 0.0;  // nan
    } else if (x == 0) {
        res = -1 / 0.0;
    } else if (x > 1) {
        int counter = 0;
        while (x > 1) {
            x /= 10;
            counter++;
        }
        res = s21_log(x) + counter * s21_LOG_10;
    } else if (x < 0.1) {
        int counter = 0;
        while (x < 0.1) {
            x *= 10;
            counter++;
        }
        res = s21_log(x) - counter * s21_LOG_10;
    } else {
        x -= 1;
        long double dif = 1;
        long double res2 = x;
        int k = 1;
        while (dif > PREC) {
            long double current = 1;
            for (int j = 1; j <= k; ++j) {
                current *= x;
            }
            current /= k;
            res += pow(-1, k + 1) * current;
            if (k > 1) dif = fabs(res - res2);
            res2 = res;
            k++;
        }
    }
    return res;
}

long double s21_tan(double x) {
    long double res = 0;
    int flag_minus = 1;
    if (x < 0) {
        x = -x;
        flag_minus = -1;
    }
    x = shift_2pi(x);
    while (x > s21_PI) x -= s21_PI;
    x = x * flag_minus;
    res = s21_sin(x) / s21_cos(x);
    return res;
}

long double s21_sqrt(double x) { return s21_pow(x, 0.5); }

long double s21_pow(double base, double exp) {
    long double res = 0;
    int flag_minus = 1;
    if (base < 0 && s21_fabs(exp - (int)exp) > 0.000001) {
        res = 0 / 0.0;
    } else {
        res = s21_exp(exp * s21_log(s21_fabs(base)));
    }
    if (base < 0 && s21_abs((int)exp % 2) == 1) {
        flag_minus = -1;
    }
    // printf("%d\n", (int)exp % 2);
    return flag_minus * res;
}

double shift_2pi(long double x) {
    int flag_minus = 1;
    if (x < 0) {
        x = -x;
        flag_minus = -1;
    }
    while (x > s21_PI_9) x -= s21_PI_9;
    while (x > s21_PI_8) x -= s21_PI_8;
    while (x > s21_PI_7) x -= s21_PI_7;
    while (x > s21_PI_6) x -= s21_PI_6;
    while (x > s21_PI_5) x -= s21_PI_5;
    while (x > s21_PI_4) x -= s21_PI_4;
    while (x > s21_PI_3) x -= s21_PI_3;
    while (x > s21_PI_2) x -= s21_PI_2;
    while (x > 2 * s21_PI) x -= 2 * s21_PI;
    return flag_minus * x;
}

long double s21_asin(double x) {
    int flag_minus = 1;
    if (x < 0) {
        x = -x;
        flag_minus = -1;
    }
    long double res = 0;
    if (x > 1) {
        res = 0 / 0.0;
    } else if (x > 1 / s21_sqrt(2)) {
        res = s21_PI_POPOLAM - s21_asin(s21_sqrt(1 - x * x));
    } else {
        long double dif = 1;
        long double res2 = x;
        int k = 0;
        while (dif > PREC) {
            long double current = 1;
            for (int j = 1; j <= 2 * k + 1; ++j) {
                current *= x;
                if (j % 2 == 0 || j == 2 * k + 1)
                    current /= j;
                else
                    current *= j;
            }

            res += current;
            if (k > 0) dif = s21_fabs(res - res2);
            res2 = res;
            k++;
        }
    }
    return flag_minus * res;
}

long double s21_acos(double x) { return s21_PI_POPOLAM - s21_asin(x); }

long double s21_atan(double x) {
    long double res = 0;
    int f_minus = 1;
    if (x < 0) {
        x *= (-1);
        f_minus = -1;
    }
    if (x < 0.9) {
        res = old_s21_atan(x);
    } else if (x > 1) {
        res = s21_PI_POPOLAM - s21_atan(1 / x);
    } else {
        res = s21_asin(x / s21_sqrt(1 + x * x));
    }
    return f_minus * res;
}

long double old_s21_atan(double x) {
    long double res = 0;
    long double dif = 1;
    long double res2 = x;
    int k = 0;
    while (dif > PREC) {
        long double current = 1;
        int j;
        for (j = 1; j <= 2 * k + 1; ++j) {
            current *= x;
        }
        if (j != 0) {
            current /= (j - 1);
        }
        res += s21_pow(-1, k) * current;
        if (k > 0) dif = s21_fabs(res - res2);
        res2 = res;
        k++;
    }
    return res;
}