Manipulating Timestamp

[#1]

Hi I am struggling to convert a Timestamp into numeric format. I basically want to use the timestamp to create an Elapsed Time column. I am having difficultly achieving this with JMP16. Below is an example of the format. The change from 12:59 to 01:00 also seems to cause issues for me.

I was able to work with excel and manipulate the data to give me an Elapsed time in minutes (from row 1 as starting point). But I would prefer to use JMP and to create a script for it.

Thanks

[#2]

thank you very much for your help. your script is working well for me even when in UK date/time settings.

[#3]

I am not seeing the error.  See the display below.  I have also attached my data table.  The Time 2 column is the same values as the time column, but with the display format set to display the actual numeric data values behind the date/time.  It is the number of seconds since January 1, 1904.  Time 2 has the formula       :time   but the format is changed to Fixed Dec, 20, 3.

I ran the code under both JMP 16 and 17, with the same results.