Thanka lot for your patient answers. I understand the way to use graph build to do it with your description theoretically.
I think I am still stuck in one point that how you input the data in the table. Since my data format has one dimension of time series by hh:mm:ss and one dimension of well position (A1, B2 etc). If you put well ID in a column, then the time data will be in row. While my exact time info will be as a separate row, which means under a column, the data is mixed up. How do you deal with this? Thanks