c program of homework1

homework1/homework1ottSalla.c

+#include <stdio.h> //using only stdio.h and not math.h for powers to make the program more lightweight
+float function(float x){//this is the function itself, returns the value when given the input; a function of a function
+	
+	return (4*x*x*x + 3*x*x + 2*x - 4) / (2 + 1/x);
+			
+}
+
+int main(){
+	float x, // input of the function, called A in the task description, using x as it is in the original function
+		value, //the value of the function
+		H, //the step
+		YM;//minimum value of function
+	int	i = 0;//for counting the number of executions of the function
+	
+	//setup for the calculations
+	
+	printf("this program calculates the function y = (4*x*x*x + 3*x*x + 2*x - 4) / (2 + 1/x) a maximum of 15 times\n");
+	printf("please input starting value\n");
+	scanf("%f", &x); //scanning the starting value
+	
+	printf("please input the step (has to be larger than 0)\n");
+	scanf("%f", &H);//scanning the step
+		while(H <= 0){//making sure it's bigger than 0, if not, prompts the user again.
+			printf("the step has to be larger than 0\n");
+			scanf("%f", &H);
+		}
+		
+	printf("please input the lower function value\n");
+	scanf("%f", &YM);//scanning the lower limit
+	
+	
+	while(i < 15){//starts the loop, exits on the 16th time
+				
+		if(x == -0.5 || x == 0){ //in these cases the function would divide by 0 and that is not acceptable
+			printf("if x = %f    y = not available\n", x);
+		}else{
+			value = function(x);//the function
+			if(value >= YM){
+				printf("if x = %f    y = %f\n", x, value);//if the value is lower than YM, prints the value of the function
+			}else{
+				printf("lower limit of function exceeded");
+				break;//breaks the loop when the value is under the lower limit
+			}
+		}
+		
+		x = x + H; //increases the input by step
+		i++; //counts the executions of the function
+		
+	}
+
+	return 0;
+}