math.h teek ja arvude jagamine

Matemaatiliste funktsioonide lahendamiseks võib meil olenevalt eesmärgist olla kasutada mitu standardteeki. Peamiseks standardteegiks on math.h (https://cppreference.com/w/c/header/math.html). Kompleksarvulise matemaatika jaoks võib lisaks võtta kasutusele complex.h ja/või tgmath.h teegid.

/**
 * File:        math.c
 * Author:      Risto Heinsar
 * Created:     05.10.2015
 * Modified:    26.09.2021
 *
 * Description: Some example use of math.h library. 
 * 
 * Note:        To use math.h library You must compile the program with the
 *              linker flag "-lm", without quotes. In geany, you can add the -lm
 *              to build path under build -> set build commands.
 */

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

int main(void)
{
    // Integer division leads to integer answers with decimal places truncated
    printf("5 / 10 is %d\n", 5 / 10);
    printf("10 / 10 is %d\n", 10 / 10);
    printf("28 / 10 is %d\n\n", 28 / 10);
    
    // To get deimal places, at least one operand has to be float/double
    printf("9.0 / 10 is %.2f\n", 9.0 / 10);
    printf("9 / 10.0 is %.2f\n", 9 / 10.0);
    printf("Using typecasting: 9 / 10 is %.2f\n\n", 9 / (float)10);

    float num1 = 9;
    float num2 = -5.4f;
    float num3 = pow(num1, 2);
    
    // Using math.h functions
    printf("Num1 squared is %.2f\n", pow(num1, 2));
    printf("Num1 squared can be also found like this: %.2f\n", num3);
    printf("Number 7 to the power of 3 is: %.2f\n", pow(7, 3));
    printf("The square root of num1 is: %.2f\n", sqrt(num1));
    printf("Alternative square root: %.2f\n", pow(num1, 1.0/2.0));
    
    float equation = num1 * pow(num2, 2) + sqrt(num1);
    printf("The solution for the equation %.3f\n", equation);
    
    return 0;
}

/**

* File: math.c

* Author: Risto Heinsar

* Created: 05.10.2015

* Modified: 26.09.2021

* Description: Some example use of math.h library.

* Note: To use math.h library You must compile the program with the

* linker flag "-lm", without quotes. In geany, you can add the -lm

* to build path under build -> set build commands.

#include <stdio.h>

#include <math.h>

int main(void)

{

// Integer division leads to integer answers with decimal places truncated

printf("5 / 10 is %d\n", 5 / 10);

printf("10 / 10 is %d\n", 10 / 10);

printf("28 / 10 is %d\n\n", 28 / 10);

// To get deimal places, at least one operand has to be float/double

printf("9.0 / 10 is %.2f\n", 9.0 / 10);

printf("9 / 10.0 is %.2f\n", 9 / 10.0);

printf("Using typecasting: 9 / 10 is %.2f\n\n", 9 / (float)10);

float num1 = 9;

float num2 = -5.4f;

float num3 = pow(num1, 2);

// Using math.h functions

printf("Num1 squared is %.2f\n", pow(num1, 2));

printf("Num1 squared can be also found like this: %.2f\n", num3);

printf("Number 7 to the power of 3 is: %.2f\n", pow(7, 3));

printf("The square root of num1 is: %.2f\n", sqrt(num1));

printf("Alternative square root: %.2f\n", pow(num1, 1.0/2.0));

float equation = num1 * pow(num2, 2) + sqrt(num1);

printf("The solution for the equation %.3f\n", equation);

return 0;

}

Pane tähele

Kompileerides tuleb kompilaatorile (gcc) täiendava argumendina lisada “-lm”, ilma jutumärkideta. Selle abil lisatakse linkuri poolt matemaatika teek.
Matemaatika funktsioonid reeglina tagastavad oma vastuse. Kui soovime seda kasutada järgnevas kohas, peame sellesse muutujasse salvestama. Kui väärtust on vaja vaid korraks tehte osana, siis eraldi salvestamist pole vaja.
N-indat juurt on lihtne võtta astme omadusi ära kasutades. Arvudel on oluline kasutada murdarvu kirjapilti (st 1 -> 1.0). See tuleneb täisarvu ja murdarvu käsitlemise erinevusest jagamisel