refactoring: change parameter and variable names

src/reihen.c

@@ -20,10 +20,10 @@ unsigned long long fac(int x){
     return prod;
 }
 
-double exponential(double x){
+double exponential(double exp){
     double sum = 0.0;
     for(int i = 0; i<=21; i++){
-        sum += (1.0/fac(i)*(powerD(i,x)));
+        sum += (1.0/fac(i)*(powerD(i,exp)));
     }
     return sum;
 }
@@ -32,13 +32,13 @@ double euler(){
     return exponential(1);
 }
 
-double squashDegreesTo360(double x){
-    int multiple = x / 360;
-    return x - (360*multiple);
+double squashDegreesTo360(double degrees){
+    int multiple = degrees / 360;
+    return degrees - (360*multiple);
 }
 
-double radians(double d){
-    return d * PI / 180;
+double radians(double degrees){
+    return degrees * PI / 180;
 }
 
 double pi(double eps){
@@ -56,19 +56,20 @@ double pi(double eps){
     return pi;
 }
 
-double sinD(double x){
-    if (x>=360.0){
-        x = squashDegreesTo360(x);
+double sinD(double degrees){
+
+    if (degrees>=360.0){
+        degrees = squashDegreesTo360(degrees);
     }
     double sum = 0.0;
     double currvalue;
-    x = radians(x);
+    double radian = radians(degrees);
     double power;
     unsigned long long faculty;
     for (int i = 0; i <= 9; i++)
     {
         currvalue = 1.0;
-        currvalue *= powerD(2*i+1,x);
+        currvalue *= powerD(2*i+1, radian);
         currvalue /= (double) fac(2*i+1);
         if(i%2==0) sum += currvalue;
         else sum -= currvalue;

src/reihen.h

@@ -1,10 +1,10 @@
 #ifndef REIHEN_H
 #define REIHEN_H
 
-double exponential(double x);
+double exponential(double exp);
 double euler();
 double pi();
-double radians(double d);
-double sinD(double d);
+double radians(double degrees);
+double sinD(double degrees);
 
 #endif // reihen.h