Merge branch 'Exponent' into 'master'

Exponent

See merge request fdai7848/Linkes-Twix!2

src/exponent.c

@@ -0,0 +1,86 @@
+#include <stdio.h>
+#include <limits.h>
+
+#include "exponent.h"
+
+double absD(double x){
+    if(x<0){
+        return -1 * x;
+    }
+    return x;
+}
+
+double p(double exp, double base){
+    double prod = 1.0;
+    if(exp==0.0){
+        return 1;
+    }else{
+        for(int i = 1; i <= (int) exp; i++){
+            prod *= base;
+        }
+        return prod;
+    }
+}
+
+double powerD(double exp, double base){
+    if(absD(exp) - ((int) absD(exp)) < 0.000001){
+        if(exp>=0.0){
+            return p(exp, base);
+        }
+        else{
+            if (base == 0.0){
+                return -1.0;
+            }
+            return  (1.0 / p((exp*-1), base));
+        }   
+    }else if(base > 0.0){
+        if(exp>=0.0){
+            return exponential(exp*logN(base, 0.00000001));
+        }
+        else{
+            if (base == 0.0){
+                return -1.0;
+            }
+            return (1.0 / exponential((-1*exp)*logN(base, 0.00000001)));
+        }
+    }
+    return -1.0;
+}
+
+unsigned long long fac(int x){
+    unsigned long long prod = 1;
+    if(x==0) return 1;
+    for (int i = 1; i <= x; i++){
+        if (prod > ULLONG_MAX / i){
+            break;
+        }
+        prod*=i;
+    }
+    return prod;
+}
+
+
+double exponential(double x){
+    double sum = 0.0;
+    for(int i = 0; i<=21; i++){
+        sum += (1.0/fac(i)*(powerD(i,x)));
+    }
+    return sum;
+}
+
+
+
+double logN(double x, double eps){
+    if(x <= 0){
+        return -1.0;
+    }    
+    double yn = x - 1.0;
+    double yn1 = yn;
+
+    do{
+        yn = yn1;
+        yn1 = yn + 2 * (x - exponential(yn)) / (x + exponential(yn));
+    } while (absD(yn - yn1) > eps);
+
+    return yn1;
+}

src/exponent.h

@@ -0,0 +1,9 @@
+#ifndef EXPONENT_H
+#define EXPONENT_H
+
+double p(double exp, double base);
+double powerD(double exp, double base);
+double exponential(double x);
+double logN(double x, double eps);
+
+#endif // exponent.h

test/test_exponent.c

@@ -0,0 +1,150 @@
+#ifdef TEST
+
+#include "unity.h"
+
+#include "exponent.h"
+
+void setUp(void)
+{
+}
+
+void tearDown(void)
+{
+}
+
+void test_DoubleBase_ForPositiveExponent(void){
+    int r1, r2, r3;
+
+    r1 = p(2.0, -2.0);
+    r2 = p(3.0, -3.0);
+    r3 = p(4.0, 5.0);
+
+    TEST_ASSERT_EQUAL_INT(4.0, r1);
+    TEST_ASSERT_EQUAL_INT(-27.0, r2);
+    TEST_ASSERT_EQUAL_INT(625.0, r3);  
+}
+
+void test_DoubleBase_ForNegativeExponent(void){
+    float r1, r2, r3;
+
+    r1 = powerD(-1.0, 2.0);
+    r2 = powerD(-3.0, -3.0);
+    r3 = powerD(-2.0, -2.0);
+
+    TEST_ASSERT_EQUAL_FLOAT(0.5, r1);
+    TEST_ASSERT_EQUAL_FLOAT(-0.0370370373, r2);
+    TEST_ASSERT_EQUAL_FLOAT(0.25, r3);
+}
+
+void test_DoubleBase_for_positive_decimal_exponent(void){
+    float r1, r2, r3;
+
+    r1 = powerD(0.45, 3.0);
+    r2 = powerD(0.5, 9.0);
+    r3 = powerD(0.5, 2.0);
+
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 1.639474, r1);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 3.0, r2);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 1.414213, r3);
+}
+
+void test_DoubleDecimalBase_for_positive_decimal_exponent(void){
+    float r1, r2, r3;
+
+    r1 = powerD(0.31, 0.413);
+    r2 = powerD(0.5, 3.13432);
+    r3 = powerD(0.124, 10.1231);
+
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 0.760229, r1);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 1.770401, r2);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 1.332474, r3);
+}
+
+void test_DoubleBase_for_negative_decimal_exponent(void){
+    float r1, r2, r3;
+
+    r1 = powerD(-0.125, 3.0);
+    r2 = powerD(-0.5, 2.0);
+    r3 = powerD(-0.12923, 10.0);
+
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 0.871685, r1);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 0.707106, r2);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 0.742625, r3);
+}
+
+void test_DoubleDecimalBase_for_negative_decimal_exponent(void){
+    float r1, r2, r3;
+
+    r1 = powerD(-0.5, 6.2315);
+    r2 = powerD(-0.1937, 9.2309);
+    r3 = powerD(-2.2145, 22.9983);
+
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 0.400593, r1);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 0.650177, r2);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 0.000964, r3);
+}
+
+void test_exponent_edge_case(void){
+    float r1, r2, r3, r4, r5;
+
+    r1 = powerD(0, 2);
+    r2 = powerD(0, 0);
+    r3 = powerD(2, 0);
+    r4 = powerD(-3, 0);
+    r5 = powerD(0.5, -3);
+
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 1.0, r1);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 1.0, r2);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 0.0, r3);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, -1.0, r4);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, -1.0, r5);
+}
+
+void test_Exponent_with_positive_number(void){
+    double r1, r2, r3;
+
+    r1 = exponential(0.0);
+    r2 = exponential(1.0);
+    r3 = exponential(2.0);
+
+    TEST_ASSERT_EQUAL_DOUBLE(1.0, r1);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 2.718282, r2);
+    TEST_ASSERT_DOUBLE_WITHIN(0.0001, 7.389056, r3);
+}
+
+void test_Exponent_with_negative_number(void){
+    double r1, r2, r3;
+
+    r1 = exponential(-1.0);
+    r2 = exponential(-2.0);
+
+    TEST_ASSERT_DOUBLE_WITHIN(0.000001, 0.367879, r1);
+    TEST_ASSERT_DOUBLE_WITHIN(0.000001, 0.135335, r2);
+}
+
+void test_ln_with_positive_number(void){
+    double r1, r2, r3;
+
+    r1 = logN(1.0, 0.000001);
+    r2 = logN(10.0, 0.000001);
+    r3 = logN(2.5, 0.000001);
+
+    TEST_ASSERT_DOUBLE_WITHIN(0.000001, 0, r1);
+    TEST_ASSERT_DOUBLE_WITHIN(0.000001, 2.302585, r2);
+    TEST_ASSERT_DOUBLE_WITHIN(0.000001, 0.916290, r3);
+}
+
+void test_ln_with_zero_and_negative_numbers(void){
+    double r1, r2, r3;
+
+    r1 = logN(0.0, 0.000001);
+    r2 = logN(-1.0, 0.000001);
+    r3 = logN(-2.5, 0.000001);
+
+    TEST_ASSERT_EQUAL_DOUBLE(-1.0, r1);
+    TEST_ASSERT_EQUAL_DOUBLE(-1.0, r2);
+    TEST_ASSERT_EQUAL_DOUBLE(-1.0, r3);
+}
+
+
+#endif // TEST