find-mean-array()

Step 1: Define the Function

First, we will define a function called findMean. This function will take an array of integers as input.

func findMean(array: [Int]) -> Double {
    // Function body will be filled in next steps
}

Step 2: Sum Up the Elements

Within the function, the first thing we need to do is sum up all the elements in the array. Swift provides a nifty reduce method which we can use to do this.

func findMean(array: [Int]) -> Double {
    let sum = array.reduce(0, +)
    // Calculation of mean will be done in the next step
}

Step 3: Calculate the Mean

To find the mean, we'll divide the sum by the count of elements in the array. Note that we need to convert the count to a Double, because integer division would result in an integer, which wouldn't be accurate if the mean is a decimal.

func findMean(array: [Int]) -> Double {
    let sum = array.reduce(0, +)
    let mean = Double(sum) / Double(array.count)
    // Returning the result will be done in the next step
}

Step 4: Return the Result

Finally, we return the calculated mean from the function.

func findMean(array: [Int]) -> Double {
    let sum = array.reduce(0, +)
    let mean = Double(sum) / Double(array.count)
    return mean
}

Conclusion

And that's it! We now have a function that takes an array of integers and returns their mean as a Double. This function can be utilized in a variety of contexts, such as analyzing data sets, calculating average scores, etc. Here's the finished code for reference:

func findMean(array: [Int]) -> Double {
    let sum = array.reduce(0, +)
    let mean = Double(sum) / Double(array.count)
    return mean
}