76 lines
1.4 KiB
C
76 lines
1.4 KiB
C
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#include "library.h"
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long long fac(const long long x) {
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long long prod = 1;
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for (long long i = 2; i <= x; i++) {
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prod *= i;
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}
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return prod;
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}
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inline float trunc(const float x) {
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return (float)(int)(x);
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}
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inline float fract(const float x) {
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return x - trunc(x);
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}
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inline float floor(const float x) {
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return trunc(x);
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}
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inline float ceil(const float x) {
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return trunc(x + 1);
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}
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inline float round(const float x) {
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return trunc(x + 0.5f);
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}
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inline float mod(const float x, const float y) {
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const float xs = x/y;
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return (xs - floor(xs)) * 4;
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}
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float exp(const float x) {
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float sum = 0;
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// iterative counter for computing x^i
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float xpown = 1;
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// iterative counter for factorial operation i!
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float prod = 1;
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// iterate taylor series
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for (int i = 1; i < TAYLOR_SERIES_DEGREE; i++) {
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prod *= (float) i;
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sum += xpown / prod;
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xpown *= x;
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}
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return sum;
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}
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float sin(const float x) {
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float sign = -1;
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float prod = 1;
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float xpown = mod(x, 2 * PI);
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float sum = 0;
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for (int i = 1; i < TAYLOR_SERIES_DEGREE; i++) {
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sign *= -1;
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prod *= (float) i * (float) (i - 1);
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xpown *= x * x;
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sum += sign * xpown / prod;
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}
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return sum;
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}
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inline float cos(const float x) {
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return sin(x + PI * 0.5f);
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}
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inline float tan(const float x) {
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return sin(x)/cos(x);
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}
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