Thanks for all the help so far.

[matrix]

I have a vi, it takes two real values at a time, and writes it to an array, and then to a spreadsheet.
I would like to write a date/time variable to the spreadsheet as well, but i can't write it to the same array, because it is of type date/string.
How can i achieve this.

[Gorka Larrea]

If you investigate a bit the "write to spreadsheet file.vi" you'll see that the numerical values you input are transformed to strings. You can do that yourself with your numerical data, then add the time sting to it and to use "write to spreadsheet file.vi" with string input, make a COPY and change all the DBL control and indicators inside by strings. This should work for what you want.

[Jonathan_H]

Depending on how many measurements you are making, you may want to consider streaming the data to a file. The benefits are that you are continously writing the data the file and not waiting for the application to finish acquistion. Benefit.. If your system goes down, not all the data is lost. Simply open and close the file outside of your acquistion loop structure. Within the loop, write the various data types to the file using the Format Into File.vi.