Plotting Data from two lists

Getting Started
1

Very simple question: I have two arrays, one which contains time values, and one that contains values of f(t). I want to use XOJO’s native graphing tools for this, could someone provide me with some code that would work. This is what I am doing now which is not working:

Var ds As New ChartLinearDataset(“Sales”, Color.Blue, True, GraphData)
Var ds1 As New ChartLinearDataset(“Sales”, Color.Blue, True, TimeData)
MainGraphDataChart.AddDataset(ds)
MainGraphDataChart.AddDataset(ds1)

2

One of the examples that comes with Xojo has this code:

Me.Title = "UK Pound to Dollar / Euro Exchange Rate Over the Years"
Me.Mode = DesktopChart.modes.Bar
Me.GridColor = Color.Clear

Var dollar() As Double = Array(1.65, 1.56, 1.49, 1.25, 1.33, 1.27, 1.30, 1.35, 1.32, 1.22)
Var euro() As Double = Array(1.21, 1.26, 1.42, 1.19, 1.14, 1.12, 1.17, 1.11, 1.19, 1.13)

Me.AddLabels Array("2013", "2014", "2015", "2016", "2017", "2018", "2019", "2020", "2021", "2022")

Var dsInflaction As New ChartLinearDataset("Dollar", Color.red, True, dollar)
Var dsTemp As New ChartLinearDataset("Euro", Color.blue, True, euro)
dsInflaction.ChartType = ChartLinearDataset.ChartTypes.Bar
dsTemp.ChartType = ChartLinearDataset.ChartTypes.Bar

Me.AddDatasets dsInflaction, dsTemp

Me could be MainGraphDataChart for you.

As your code is not the complete code, we don’t know if something that you didn’t post here is missing.

3

Thank you for the response, but I have not been able to completely solve my issue.
Here is the complete code:

Var GraphData() As Double
Var TimeData() As Double

Var n as integer = ChartArray.LastIndex(2)
Var j as integer = GraphChoicePopupMenu.SelectedRowIndex

for i as integer = 0 to n
GraphData.add(ChartArray(j,i))
TimeData.Add(ChartArray(0,i))
next

MainGraphDataChart.Title = “Graph of” +GraphChoicePopupMenu.SelectedRowText
MainGraphDataChart.Mode = DesktopChart.modes.Line
MainGraphDataChart.GridColor = Color.Clear

Var ds As New ChartLinearDataset(GraphChoicePopupMenu.SelectedRowText, Color.red, True, GraphData)
ds.ChartType = ChartLinearDataset.ChartTypes.Line

MainGraphDataChart.AddDatasets ds

I know the above code won’t work but I am not sure how to fix it. GraphData and TimeData each will have over 600,000 elements, I want to plot points on the graph of the form (TimeData(i),GraphData(i)). Is there a way to make each point in graph data correspond to a time value and then plot this?

Thanks again.

4

I can imagine plotting this amount of data being slow, and you won’t be able to distinguish between 600000 and (as a guess) 600 plotted data points.

Once you get the graph working, maybe you could consider this.

Julen

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