How do I use while loop to cycle through 3 cases and stop after evaluating the three cases?

My homework problem reads:

"A mathematical relationship between x and y is described by the following expressions:

y=A*exp(x^2)-B*x^3+x-1 if x<=0 (Case 1)

y=A*log10(x)-B*x^4+1.5 if 0<x<=10 (Case 2)

y=A/log(x)-B/x+C if x>10 (Case 3)

where A, B, and C are constants. Write a program that inputs the constants A,B,C, and the argument x, and computes the corresponding value of y. Print x by using 4 decimal places, and y by using 5 decimal places.

Use if/else statements to choose the proper expression for y, corresponding to selected x.

After reading A,B,C, your program should use a while loop to evaluate y for scanned x in each of the above three cases. If you input x from the same interval again, your program should ask you to input x from another interval, until you input x once from each interval.

Your output should look like:

Enter A, B, C:

-1.5 2.5 0.125

Enter x: -3.5

Case 1

x value is = -3.5000 and y value is = -313369.24580

Enter x: -5

Enter x from another interval!

Enter x: 1.85

Case 2

x value is = 1.8500 and y value is = -28.18452

Enter x: 12

Case 3

x value is = 12.0000 and y value is = -0.68698"

So far i have the if/else conditions down but i'm not sure how to proceed with the while loop. any guidance will be appreciated!

[James Tursa]

Please post the code you have so far so we can comment on the next steps.

Answer 1

[Stalin Samuel]

A = -1.5;B = 2.5; C= 0.125;

count=[1 1 1]%three one for three cases
while(sum(count)>0)
    x = input('enter the value of x:');
    if x<=0
        if count(1)>0
            count(1) = 0;%fisrt case tested
            y=A*exp(x^2)-B*x^3+x-1 
        else
             disp('enter another no')
        end
    elseif x>0&x<=10
        if count(2)>0
            count(2) = 0; %second case tested
            y=A*log10(x)-B*x^4+1.5
        else
            disp('enter another no')
        end
    elseif x>10
        if count(3)>0
            count(3) = 0;%third case tested
            y=A/log(x)-B/x+C
        else
            disp('enter another no')
        end
    end
end