How to separate an variable array into smaller arrays using swift - swift

Question

I have a question I cannot figure out. Is there an easier way to separate an array into other arrays. In the code below I do a Trace route and filter out everything except the ping rates.
Then I break down that array into individual nodes. The only downside is if it only takes 2 hops then I get an error, "fatal error: Index out of range." because I have it set up to create 15 node arrays. I have also tried putting ..
let count = pingRate.count
if count < 15 {
aNodeArray += pingRate[14]
}
Is there an easier way? I wish there was a way to do a .count and then populate the Int the is required on each node.
let task = Process()
task.launchPath = "/bin/sh"
task.arguments = ["-c", "traceroute -nm 15 -q 1 8.8.8.8"]
let pipe = Pipe()
task.standardOutput = pipe
task.launch()
let data = pipe.fileHandleForReading.readDataToEndOfFile()
let output = NSString(data: data, encoding: String.Encoding.utf8.rawValue) as! String
var array = output.components(separatedBy: " ")
array = array.filter({ $0.contains(".")})
let pingRate: [[Double]] = array.enumerated().filter({ index, _ in
index % 2 != 0
}).map { [Double($0.1)!] }
let aNode = pingRate[0]
let bNode = pingRate[1]
let cNode = pingRate[2]
let dNode = pingRate[3]
let eNode = pingRate[4]
aNodeArray += aNode
bNodeArray += bNode
cNodeArray += cNode
dNodeArray += dNode
eNodeArray += eNode
Once I get that done then I sort and find the min, max, and average.
let sorted = aNodeArray.sorted()
let numbers = sorted
print(numbers)
let min = numbers[0]
var sum = 0 as Double
for number in numbers {
sum += number
}
let mean = Double(sum) /
Double (numbers.count)
let x = mean
let avg = round(1000.0 * x) / 1000.0
let maxBR = numbers.last! as Double
let max = round(1000.0 * maxBR) / 1000.0
print(min)
print(max)
print(avg)
Edit
I did stumble upon chunks and stride from...
Swift: what is the right way to split up a [String] resulting in a [[String]] with a given subarray size?
I am trying to figure a way to implement that for my needs
Edit
And looking at that code. Can anyone tell me why I get the Color spinning wheel until the process() is finished?

Answer 1

I know that there are more efficient algorithms to calculate your ping rate statistics but the code below should do the job.
let task = Process()
task.launchPath = "/bin/sh"
task.arguments = ["-c", "traceroute -nm 15 -q 1 8.8.8.8"]
let pipe = Pipe()
task.standardOutput = pipe
task.launch()
let data = pipe.fileHandleForReading.readDataToEndOfFile()
guard
let pingRates = String(data: data, encoding: .utf8)?
.components(separatedBy: " ")
.filter({ $0.contains(".") })
.flatMap({ Double($0) }),
pingRates.count > 0
else {
return
}
print("ping rate(min) = \(pingRates.min()!.rounded())")
print("ping rate(max) = \(pingRates.max()!.rounded())")
print("ping rate(avg) = \((pingRates.reduce(0, +) / Double(pingRates.count)).rounded())")
The trick to eliminating the IP addresses in your output is to let Double.init fail on them and then flatMap will remove those nil values.