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Reference raster postings to map coordinates

A map postings raster reference object contains information that describes the relationship between a planar map coordinate system and an intrinsic coordinate system that is anchored to the columns and rows of a 2-D spatially referenced grid of point samples (or postings).

Typically, the raster is sampled regularly in the planar world *x*-
and world *y*-coordinates of the map system, such that the intrinsic
*x* and world *x*axes align and the intrinsic
*y* and world *y* axes align. When this is true,
the relationship between the two systems is rectilinear. More generally, and much more
rarely, their relationship is affine. The affine relationship allows for a possible
rotation (and skew). In either case, rectilinear or affine, the sample spacing from row
to row need not equal the sample spacing from column to column.

This image illustrates a 9-by-11 planar raster of postings. The postings are spaced 1
meter apart in *x* and *y*, cover *x*
values in the range [40,50] in meters, and cover *y* values in the
range [20,28] in meters. The boundary of the raster of postings is a rectangle with
edges that pass through the outermost postings.

To reference a raster of cells to planar map coordinates, use a `MapCellsReference`

object instead.

You can use these functions to create `MapPostingsReference`

objects:

`readgeoraster`

— Import a raster data file as an array and a reference object.`maprefpostings`

— Create a map raster reference object by specifying the*x*and*y*world limits of the raster and either the size of the raster or the spacing of the postings.`maprasterref`

— Convert a world file to a map raster reference object.`refmatToMapRasterReference`

— Convert a referencing matrix to a map raster reference object.

`contains` | Determine if geographic or map raster contains points |

`firstCornerX` | Return world x-coordinate of map raster index
(1,1) |

`firstCornerY` | Return world y-coordinate of map raster index
(1,1) |

`intrinsicToWorld` | Transform intrinsic to planar world coordinates |

`sizesMatch` | Determine if geographic or map raster object and image or raster are size-compatible |

`worldFileMatrix` | Return world file parameters for transformation |

`worldGrid` | World coordinates of raster elements |

`worldToDiscrete` | Transform planar world to discrete coordinates |

`worldToIntrinsic` | Transform planar world to intrinsic coordinates |