Easygrapher v4.6: Software for Data Visualization and Statistical Evaluation of the DSSATv4.6 and CANBv4.0 Models.

Crop simulation models are process-based and can provide very detailed outputs of the simulated crop and soil processes. However, analyzing the outputs is a challenge. EasyGrapher (EG) is a graphical and statistical software program designed for the DSSAT v4.x software, and it also supports graphing and data management of the Canadian Agricultural Nitrogen Budget (CANB) model. EG v4.6 allows users to graph one output file at a time to show two types of graph (i.e., time-series, XY-plot) within minutes and calculates evaluation statistics for each of the output variables. Specifically, EG v4.6 can support 16 outputs of DSSAT v4.6 to: (1) create time-series graphs and display measured data in the simulation graph; (2) graph simulated data against measured data, and (3) calculate evaluation statistics (RMSE, E, EF and d). Recently, we have developed an “EG-Tester” version which graphs all 16 DSSAT outputs automatically within minutes. This version will save a lot of time for end users when displaying DSSAT results with graph and evaluation statistics. The EG-CANB version supports outputs of CANB v4.0 to create bar plots for spatial-series graphs in various scales, and to manipulate CANB output data transfer to MS Excel. The EG program has the potential to carry out graphic and statistical tasks for other models as well. Graphic and statistical evaluation examples were illustrated using the field dataset collected from our experiments in Canada and China, as well as the dataset residing in the DSSAT software.

Keywords: EasyGrapher, DSSAT, Statistical Evaluation, CANB