GUInterp is a Graphical User Interface (GUI) supporting the spatial interpolation of points data. The purpose of the GUI is to provide graphical tools to perform the steps commonly required to interpolate points data within defined borders: filtering outliers, defining a suitable variogram (in case of Kriging interpolation), choosing the grid of the output raster and setting the best options to weigh up computational speed and output accuracy.

GUInterp is currently in beta version.

## Installation

The package can be installed from GitHub:

install.packages("remotes")
remotes::install_github("ranghetti/guinterp")

## Usage

The GUI can be launched with the following command:

library(guinterp)
guinterp()

Once opened, the GUI allows user to import a points dataset and an optional polygon file of borders (alternatively, the bounding box of points is used). Points data must contain the variable to be interpolated (a selector allows selecting it). In case multiple polygons are loaded, they can be treated as separate objects during interpolation.

After loading files, the main GUI appears. In the left column, data can visualised thanks to a histogram and a map; both of them highlight filtered vs. non-filtered points. The right column incudes parameter selectors, organised in four boxes:

• Filter data contains selectors useful to filter data;
• Output format allows defining the output raster grid;
• Interpolation settings allows choosing the interpolation method (IDW or Kriging) and, in this case, defining the semivariogram model with another interactive interface;
• Processing settings includes fine-tuning settings to speed-up interpolation.

## Credits

GUInterp is being developed by Luigi Ranghetti and Lorenzo Busetto (IREA-CNR), and it is released under the GNU General Public License version 3 (GPL‑3).

To cite this package, please use the following entry:

L. Ranghetti and L. Busetto (2020). GUInterp: a Shiny GUI to support spatial interpolation. R package version 0.2.6. DOI: 10.5281/zenodo.3843327. URL: http://guinterp.ranghetti.info/.

@Manual{guinterp_rpkg,
title  = {GUInterp: a Shiny GUI for Spatial Interpolation},
author = {Ranghetti, Luigi and Busetto, Lorenzo},
year   = {2020},
note   = {R package version 0.2.6},
doi    = {10.5281/zenodo.3843327},
url    = {http://guinterp.ranghetti.info/},
}

## Contributing

This project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms.