cfman
I think you will have to write a function to integrate the pdf
yourself.
Within a spreadsheet you can use the FREQUENCY() function on very
small partitions/bins to create the data via which you chart the pdf,
then doing a cumulative sum of the results will give a good
approximation of the cdf...works best on a large data set.
Within VBA I use the following functions to create a 2-d array of
breaks and frequencies...you could add a 3rd dimension to keep a
running total of the frequencies and chart that for the cdf.
Function Hist2(Breaks As Long, arr() As Double, Optional
FreqAsPercentage As Boolean = False)
'calculates bins and frequencies for an array
' where Breaks = no. of breaks
'have to use the GetMax and GetMin functions as arr is likely to have
more than 65,535 elements
Dim i As Long, j As Long, ArrSize As Double
Dim length As Double
Dim MaxValue As Double
Dim MinValue As Double
ReDim breaksNfreq(1 To Breaks, 1 To 2) As Double 'first column is
breaks, second is freq
'Assign initial value for the frequency array
For i = 1 To Breaks
breaksNfreq(i, 2) = 0
Next i
MaxValue = GetMax(arr)
MinValue = GetMin(arr)
'Linear interpolation
length = (MaxValue - MinValue) / Breaks
For i = 1 To Breaks
breaksNfreq(i, 1) = MinValue + length * i
Next i
'Counting the number of occurrences for each of the bins
For i = LBound(arr) To UBound(arr)
If (arr(i) <= breaksNfreq(1, 1)) Then breaksNfreq(1, 2) =
breaksNfreq(1, 2) + 1
If (arr(i) >= breaksNfreq(Breaks - 1, 1)) Then
breaksNfreq(Breaks, 2) = breaksNfreq(Breaks, 2) + 1
For j = 2 To Breaks - 1
If (arr(i) > breaksNfreq(j - 1, 1) And arr(i) <=
breaksNfreq(j, 1)) Then
breaksNfreq(j, 2) = breaksNfreq(j, 2) + 1
Exit For
End If
Next j
Next i
If FreqAsPercentage = True Then
ArrSize = (UBound(arr) - LBound(arr) + 1)
For i = 1 To UBound(breaksNfreq)
breaksNfreq(i, 2) = breaksNfreq(i, 2) / ArrSize
Next i
End If
Hist2 = breaksNfreq()
End Function
Function GetMax(arr() As Double) As Double
Dim i As Long
Dim j As Long
Dim z As Long
i = LBound(arr)
j = UBound(arr)
GetMax = arr(i)
For z = i + 1 To j
If arr(z) > GetMax Then GetMax = arr(z)
Next z
End Function
Function GetMin(arr() As Double) As Double
Dim i As Long
Dim j As Long
Dim z As Long
i = LBound(arr)
j = UBound(arr)
GetMin = arr(i)
For z = i + 1 To j
If arr(z) < GetMin Then GetMin = arr(z)
Next z
Hope that helps
Lloyd
