ARIA (App foR ImpAct)

Role

App foR ImpAct (ARIA) is an R package which helps in providing a user friendly way to extract and browse some basic results from an IMPACT (International Model for Policy Analysis of Agricultural Commodities and Trade) model run.

Dependencies

ARIA is built using two R libraries developed in house by the Foresight and Policy Modeling Unit of International Food Policy Research Institute (IFPRI).

The two libraries are DOORMAT and reportIMPACT, both of which are available on GitHub on the following links:

https://github.com/IFPRI/DOORMAT

https://github.com/IFPRI/reportIMPACT

Usage

Loading library

To browse some basic outputs from ARIA, the first step is to load the required ARIA library using:

library(ARIA)

What does the app do?

The core function to fireup the app locally on your computer is called appIMPACT.

appIMPACT requires the location of the ./OutputFiles/Scenarios folder loaction in the IMPACT model directory before it can extract the results from a gdx file which contains the final outputs from an IMPACT model run.

appIMPACT can also take a base_year argument to calculate some relative indicators. If this argument is not provided, the app with automatically try to capture the first available datapoint in the IMPACT results for calculation of relative indicators.

Using the app

The first step is to provide the folder argument to appARIA. This can be done in two ways:

1. Savig the ./OutputFiles/Scenarios path in an R object

This can be done by using

my_impact_results_folder <- "<path/to/impact/folder>/OutputFiles/Scenarios"

This object can then be passed on to the appIMPACT function

appIMPACT(folder = my_impact_results_folder)

2. Passing the ./OutputFiles/Scenarios path directly to the function call

Alternatively, you can pass on the folder path directly to the app using

appIMPACT(folder = "<path/to/impact/folder>/OutputFiles/Scenarios")

App Navigation

Before the app is fired up on your computer, make sure to pay extra attention to the messages on your R console. The app will ask you some questions before processing the results from the gdx file(s). The app will also display some messages regarding what it is trying to do in the background.

Once ready with the prompts, the app will fire up with an additional R window or your default browser.

Questions

In case of questions / problems please contact Abhijeet Mishra ()