29 lines
362 B
C
29 lines
362 B
C
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#include "config.h"
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double positive (double x) {
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if (x > 0.0)
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return x;
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else
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return 0.0 - x;
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}
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double sqrt (double a) {
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double x_old = 1.0, x_new = 0.5;
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if (a > 0.0) {
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do {
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x_old = x_new;
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x_new = ((a / x_old) + x_old) / 2.0;
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} while (positive(x_old - x_new) > MY_DELTA_MAX);
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return x_new;
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} else exit(1);
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}
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