You should try using Preview when opening your csv file. It will let you see what JMP is doing with the data
- Go to File=>Open
- At the far right, lower portion of the window, click on the File Type drop down arrow and select "Text Files (*.txt,*.csv,*.dat,*.tsv)
- Select in the "Open as" area, "Data (Using Preview)
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After you select the file you want, and click on Open, the Preview Wizard will guide you through the .csv import process, and you will see a preview of how JMP is interpreting the data
Jim