# world2grid

Convert world coordinates to grid indices

## Syntax

``ij = world2grid(map,xy)``

## Description

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````ij = world2grid(map,xy)` converts an array of world coordinates, `xy`, to an array of grid indices, `ij` in ```[row col]``` format.```

## Examples

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Create a 10 m-by-10 m empty map.

`map = occupancyMap(10,10,10);`

Update the occupancy of world locations with specific probability values and display the map.

```x = [1.2; 2.3; 3.4; 4.5; 5.6]; y = [5.0; 4.0; 3.0; 2.0; 1.0]; pvalues = [0.2 0.4 0.6 0.8 1]; updateOccupancy(map,[x y],pvalues) figure show(map)``` Inflate occupied areas by a radius of 0.5 m. Larger occupancy values overwrite the smaller values.

```inflate(map,0.5) figure show(map)``` Get grid locations from world locations.

`ij = world2grid(map,[x y]);`

Set grid locations to occupied locations.

```setOccupancy(map,ij,ones(5,1),'grid') figure show(map)``` ## Input Arguments

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Map representation, specified as a `occupancyMap` object. This object represents the environment of the sensor. The object contains a matrix grid with values representing the probability of the occupancy of that cell. Values close to 1 represent a high probability that the cell contains an obstacle. Values close to 0 represent a high probability that the cell is not occupied and obstacle free.

World coordinates, specified as an n-by-2 matrix of ```[x y]``` pairs, where n is the number of world coordinates.

Data Types: `double`

## Output Arguments

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Grid indices, returned as an n-by-2 matrix of ```[i j]``` pairs in ```[row col]``` format, where n is the number of grid positions. The grid cell locations are counted from the top left corner of the grid.

Data Types: `double`