The DIAdem.ToDatasheet offers functions to export an data area (ValueRangeGet and ValueRangeFormatedGet). This allows you to store all data of a certain area in vector variables.
Unfortunately it seems that Excel does not support a similar method to set a data area. Allthough you can mark a range to change properties of a number of cells at the same time I think you will have to set the value of each cell individually.
I found some lines in a vb-example that might help you:
'Add data to the spreadsheet. The data is input to Excel one point at a time,
'by going stepping through the array one point at a time, and placing it in
'its assigned cell. The cell location is determined by converting the column
'index of the array into an a
scii value, and adding 65. So the first column
'of data fills to the ASCII equivalent of 65, which is "A". Note that this
'is only valid for columns A through Z, but since data acquisition rarely
'takes place on more than 16 channels, the limit is not restrictive.
For x = 0 To numchannels
For y = 0 To numscans
.Range(Chr(x + 65) + CStr(y + 10)).Value = ScaledData(x, y)
Next
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