Charting Data Directly From Your Program

Often it may not be convenient to load chart data from a file. For example, if the data is created from within the program using a mathematical calculation, it makes more sense to read it into the chart directly instead of saving it to a file and then reading it again. Not only can this method be quicker, it can also be quite easy to program.

The following example creates a 2-dimensional array, populates the array with data, and then charts the data:

Sub Main

' Declare the arrays needed to do the calculations

Dim Rates(1 To 2) As Double

Dim Values(1 To 2, 1 To 12) As Double

' Set the number of series and points in the chart

Chart2D1.ChartGroups(1).Data.NumSeries = 2

Chart2D1.ChartGroups(1).Data.NumPoints(1) = 12

Chart2D1.ChartGroups(1).Data.NumPoints(2) = 12

' Set the different rates

Rates(1) = 0.17

Rates(2) = 0.089

' Set the initial values for the first and second series

Values(1, 1) = 200

Values(2, 1) = 200

' Populate the Values arrays with data

For i = 1 To 2

For j = 2 To 12

' Calculate the current value of the investment using the

' following calculation:

Values(i, j) = Values(i, j - 1) * Rates(i) + Values(i, j - 1)

Next j

Next i

' Set the common X values

For i = 1 To 12

Chart2D1.ChartGroups(1).Data.x(1, i) = I

Next i

' Set the Y values

For i = 1 To 2

For j = 1 To 12

Chart2D1.ChartGroups(1).Data.y(i, j) = Values(i, j)

Next j

Next I

End Sub