# auremask: Create and manipulate a window of analysis for landscape... In aurelhy: Hydrometeorological interpolation

## Description

An AURELHY window of analysis ('auremask' object) specifies the regions relative to the point that define the various variables describing the landscape.

## Usage

 ```1 2 3 4 5 6 7``` ```auremask(type = "radial", dist = c(1, 6, 11, 16, 21, 26), angles = 0:7 * pi/4 + 0.01, n = 11, keep.origin = FALSE) ## S3 method for class 'auremask' print(x, geomat, ...) ## S3 method for class 'auremask' plot(x, y, ...) ```

## Arguments

 `type` the type of window, either `"radial"` (by default), or `"rectangular"` as in the initial version of the AURELHY method. `dist` A vector of distances (in km) to consider in the window for the `"radial"` window, or the distance to consider between two grid points for a `"rectangular"` window (in this case, if you provide several distances, only the smallest one will be considered) `angles` A vector of angles in radians to use to construct a `"radial"` window. This argument is ignored for `"rectangular"` window. Avoid to use angles parallels to the grid, like 0 or pi/4, because you will have points going into one or the other sector of your window of analysis, depending on rounding of the numbers in the floating-point calculations! A slight shift angle (0.01, by default) avoids this unstability `n` The number of grid points in latitude and longitude to use for a `"rectangular"` window. For instance, if `n = 11`, the window will be made of 11*11 = 121 points (minus one if `keep.origin is FALSE`). This argument is ignored for a `"radial"` window. `keep.origin` Is the origin where the window is centered considered as one point of the grid, or not (by default, not, as in the original implementation of the AURELHY method) `x` An 'auremask' object `geomat` A reference grid, as a 'geomat' object against which the window of analysis is tested (print or plot the number of points that are located in each sector of the window) `y` Same as `geomat` `...` further arguments passed to the function

## Details

`auremask()` creates a new window of analysis. The object has `print()` and `plot()` methods.

## Value

An 'auremask' object with all information required to mask a 'geotm' object (terrain model) for creating landscape variables required by the AURELHY method.

## Author(s)

Philippe Grosjean <[email protected]>

`polar.coords`, `geomat`
 ```1 2 3 4 5 6 7 8``` ```# Default window of analysis am <- auremask() am # Get an example terrain model and apply the window on it data(morocco) plot(am, morocco) # Further statistics are displayed with print() if a grid is provided too print(am, morocco) ```