Swift - fatal error: Array index out of range

Question

I'm trying to populate an array with numbers with an increase of 0.1 each like: [0.1,0.2,0.3...]

This code is giving me the error: fatal error: Array index out of range. What am I missing? I thing im declaring something wrong.

I will save it into a structure of type Double.

My Code

import UIKit

class PrecoDomicilioViewController: UIViewController,UIPickerViewDelegate, UIPickerViewDataSource{

@IBOutlet var euros: UIPickerView!

var pickerData:[Double] = []


override func viewDidLoad() {
    super.viewDidLoad()

    euros.delegate = self
    euros.dataSource = self




    for var i = 0; i <= 200; i++
    {
        pickerData[i] += 0.1
    }

}

func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
return 1
}

func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {

    return pickerData.count
}

func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String! {

    return "\(pickerData[row])"
}

func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    restaurante.portes = pickerData[row]
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
}


}
}

UPDATE: Finally made it, but there are this strange numbers between 6 and 10.

enter image description here

You really need a separate question. Hint: floating point numbers can not represent most decimal numbers (non whole numbers) exactly, that is what you ar seeing here. It is a problem when changing bases, here from base 10 to base 2 which Double uses. For exact decimal numbers such as for money and calculators use NSDecimalNumber. — zaph
– zaph, Commented Aug 29, 2015 at 16:16

zaph · Accepted Answer · 2015-08-29 16:08:07Z

2

You can not add items to a Swift array with the subscript operator, you need to use append.

NOTE You can’t use subscript syntax to append a new item to the end of an array.”

Excerpt From: Apple Inc. “The Swift Programming Language (Swift 2 Prerelease).” iBooks. https://itun.es/us/k5SW7.l

Use append(), examples:

shoppingList.append("Flour")
pickerData.append(0.1)

edited Aug 29, 2015 at 16:08

answered Aug 29, 2015 at 15:58

zaph

113k21 gold badges196 silver badges234 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Renato Pimpão Over a year ago

How do I populate with append?

Renato Pimpão Over a year ago

Solved my question. In other languages we simply use +=. Thank you.

zaph Over a year ago

In Swift += is used for append an array, ex: shoppingList += ["Baking Powder", "Tomatoes"]

Collectives™ on Stack Overflow

Swift - fatal error: Array index out of range

1 Answer 1

3 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related