![]() Those who are interested in a fuller treatment of the raster or terra package are referred to Spatial Data Science with R and “terra” or Chapters 3, 4, and 5 of Geocomputation with R, respectively.Įven though the terra package is a replacement of the raster package and it has been out on CRAN for more than several years, we still learn the raster object classes defined by the raster package and how to switch between the raster and terra object classes. For example, we do not cover raster arithmetic, focal operations, or aggregation. ![]() Therefore, we will introduce only the essential knowledge of raster data operation required to effectively implement the task of extracting values, which will be covered extensively in Chapter 5. Key differences will be discussed and will become clear later.įor economists, raster data extraction for vector data will be by far the most common use case of raster data and also the most time-consuming part of the whole raster data handling experience. The raster and terra packages share the same function name for many of the raster operations. terra is written in C++ and thus is faster than the raster package in many raster data operations. The terra package has been under active development to replace the raster package (see the most up-to-date version of the package here). However, we are in the period of transitioning from the raster package to the terra package. The raster package has been the most popular and commonly used package for raster data handling. Web graphics are generally not suitable for professional printing.In this chapter, we will learn how to use the raster and terra package to handle raster data. To recap, logo files should always be vector-based and SVG files can be used to display vector graphics online. Make sure the designer provides vector logo files when updating your logo, and ask your printer to double-check the resolution of images when professionally printed material. With this in mind, consult a graphic designer when in doubt. ![]() Raster-based images can be embedded into Adobe Illustrator, and vectors can be placed and even created in Photoshop. Any of the above file types can be exported to a pdf format, so these files can be either vector, raster, or a combination of the two.ĭisclaimer: Graphics software has come a long way, resulting in much line-blurring between programs. The small exception to these rules is the Portable Document Format (.pdf, PDF). Encapsulated PostScript File (.eps, EPS). ![]()
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