Hi, I used ENVI_GET_ROI_DATA to extract data associated with ROIs and calculate statistics of the data. The function worked fine with some ROIs but got crash, sometime, and return the error message as: " Out of range subscript encountered: ADDR. Execution halted at: ENVI_ROI_GET_ADDR ENVI_GET_ROI_DATA   Those ROIs are stored as polygon type and some of them have very narrow shape. Thank you for any suggestion to fix the problem. V. "