Step 1: Understanding the task

Our goal is to create a function called calculateVolumePyramid that calculates the volume of a pyramid.

In geometry, the volume of a pyramid is calculated using the formula V = 1/3 * base_area * height.

The base_area is calculated by length * width for a rectangular pyramid, and the height is the perpendicular distance from the base to the top of the pyramid.

In order to create this function, we will need two arguments: base_area and height.

function calculateVolumePyramid(baseArea, height) {

}

Step 2: Adding the formula

Next, we apply the mathematical formula into our function. In javascript, this will look like as follows:

function calculateVolumePyramid(baseArea, height) {
  return (1/3) * baseArea * height;
}

Step 3: Validate the Input

Now, let's validate the input before calculating. We want to ensure that baseArea and height are both positive numbers. If not, the function will return undefined, signalling that the inputs were not valid.

function calculateVolumePyramid(baseArea, height) {
  if (baseArea > 0 && height > 0) {
    return (1/3) * baseArea * height;
  } else {
    return undefined;
  }
}

Step 4: Refactor the code

Since we only have to calculate and return the volume if the base area and height are positive numbers, let's make our function more readable by returning early when either of the inputs are not valid.

function calculateVolumePyramid(baseArea, height) {
  if (baseArea <= 0 || height <= 0) {
    return undefined;
  }
  
  return (1/3) * baseArea * height;
}

Step 5: Test the function

Now it's time to verify if our function works correctly. This can be done by invoking the calculateVolumePyramid function with different values for base area and height:

console.log(calculateVolumePyramid(10,5)); // Expected output: 16.666666666666668
console.log(calculateVolumePyramid(7,2)); // Expected output: 4.666666666666667
console.log(calculateVolumePyramid(-10,5)); // Expected output: undefined
console.log(calculateVolumePyramid(10,-5)); // Expected output: undefined
console.log(calculateVolumePyramid(-10,-5)); // Expected output: undefined

Conclusion

You've just finished writing a function that calculates the volume of a pyramid. Remember, having a good idea of what your function needs to do, validating the inputs and making your code cleaner are just as important as getting the right result. Keep practicing and you'll get the hang of it in no time!