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Swift Charts - ChartYAxis - How to display a double?

In Swift Charts can the x/y: .value be a double, or does it have to be an integer?

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I'm generating a graph that is showing hours on the Y axis. Hours is hours + minutes (as a decimal) but it only seems to work with the integers and won't take doubles. Can I use a double or do I have to do a work around?

A sample part of the code is below:

Chart{
        ForEach(sunriseSunset) {item in
            LineMark(
                x: .value("Date", item.sunrise),
                y: .value("Sunrise", (((Calendar.current.dateComponents(components, from: item.sunrise).hour!) * 60) + (Calendar.current.dateComponents(components, from: item.sunrise).minute!))  / 60),
               // y: .value("Sunrise", (((Calendar.current.dateComponents(components, from: item.sunrise).hour!)) + (Calendar.current.dateComponents(components, from: item.sunrise).minute!)) * minsdecimal),
                series: .value("Date", "Sunrise")
            )
            .foregroundStyle(.orange)
            .lineStyle(StrokeStyle(lineWidth: 2))
        }
    }
    .frame(height: 300)
    .chartYAxis {
        AxisMarks(
            values: [0, 6, 12, 18, 24]
        )
    }
}
Solution

  • Yes you can have doubles for the y axis values. To get doubles, you could try something like this for your y values of hours + minutes (as a decimal) :

    y: .value("Sunrise", Double(Calendar.current.dateComponents([.hour], from: item.sunrise).hour!) + Double(Calendar.current.dateComponents([.minute], from: item.sunrise).minute!) / 60.0),

    You could of course have this in your item struct:

     var sunriseHour: Double {
     Double(Calendar.current.dateComponents([.hour], from: sunrise).hour!) + Double(Calendar.current.dateComponents([.minute], from: sunrise).minute!) / 60.0
 }

    and call:

    y: .value("Sunrise", item.sunriseHour),