I have an excel table and I want to put one column of this table in a vector in .dat file. Here is what I have : First solution with the complete path : SheetConnection sheet("C:\Users\Hor246\opl\Bushfire\month_01_omission.xlsx"); Value from SheetRead(sheet,"month_01_omission!B2:B431"); Second solution with the name : SheetConnection sheet("month_01.xlsx"); lat from SheetRead(sheet,"month_01!A2:A855856"); In both cases, when I run the project, cplex says"Value/lat is not defined" Do you know what is the problem ? Thanks