Implement SQRT () Functions

Evaluate the square of a positive number N and specify the precision. The library function SQRT must not be used.

Method 1: first calculate the integer part of SQRT (N), then calculate the first digit after the decimal point, two digits ......

Method 2: Newton Iteration Method, according to the formula ai + 1 = (AI + number/AI)/2, where the initial value of AI is A1, such as 1, 2, 3...

// Calculate the start of a positive number N and specify the precision. You must not use the library function SQRT # include <stdio. h> # include <stdlib. h> double my_sqrt2 (double number, int point) {double new_guess; double last_guess; If (number <0) {printf ("cannot compute the square root of a negative number! \ N "); Return-1;} printf (" Method 2: \ n "); new_guess = 1; do {last_guess = new_guess; new_guess = (last_guess + number/last_guess) /2; printf ("%. * lf \ n ", point, new_guess);} while (new_guess! = Last_guess); Return new_guess;} double my_sqrt1 (double N, int point) {If (n <0) {printf ("cannot compute the square root of a negative number! \ N "); Return-1;} int I, j; for (I = 1; I-n <0; I ++) // obtain the integer portion of the open I if (I * I-n> 0) break; double answer = I-1; double incr = 0.1; For (j = 1; j <= point; j ++) // obtain the J-digit {for (I = 1; I <10; I ++) {answer + = incr; If (answer * answer-N> 0) break;} answer-= incr; incr/= 10;} incr * = 10; printf ("Method 1: \ n"); printf ("SQRT (% lf) is between %. * lf-%. * lf \ n ", N, point, answer, point, answer + incr); Return answer;} int main (void) {int point; Double N; printf ("enter a positive integer N:"); scanf ("% lf", & N); printf ("Enter the digits accurate to the decimal point :"); scanf ("% d", & Point); my_sqrt1 (n, point); my_sqrt2 (n, point); Return 0 ;}

 

Implement SQRT () Functions