Layer and Data files

What is a layer? 1. A set of vector data organized by subject matter – roads, rivers, or political boundaries 1. A set of vector data organized by subject matter – roads, rivers, or political boundaries 2. A set of raster data representing a particular geographic area – aerial photograph or remotely sensed image. 2. A set of raster data representing a particular geographic area – aerial photograph or remotely sensed image. 3. A file that stores symbology and display information for a given vector or raster data set. The layer does not actually contain the data, but points to its physical location -.lyr file 3. A file that stores symbology and display information for a given vector or raster data set. The layer does not actually contain the data, but points to its physical location -.lyr file Definition based on 2001 ESRI Press – Dictionary of GIS Terminology

Def 1. A set of vector data organized by subject matter – roads, rivers, or political boundaries

Def 2. A set of raster data representing a particular geographic area – aerial photograph or remotely sensed image.

3. A file that stores symbology and display information for a given vector or raster set. The layer does not actually contain the data, but points to its physical location. View In Arc Catalog View In Windows Explorer

The layer file (.lyr) does not actually contain the data, but points to its physical location.

Saving your selections 1Save as a temporary layer file (resides only in your project) 1Save as a temporary layer file (resides only in your project) 2. Save as.lyr file 2. Save as.lyr file 3.Save as a data file (shapefile, geodatabase, etc…) 3.Save as a data file (shapefile, geodatabase, etc…)

Creating a temporary layer from Selected Features Right click on the layer in the TOC Right click on the layer in the TOC Selection Selection Create Layer from Selected Features Create Layer from Selected Features

Saving Selected features layer as a.lyr file or exporting as data file

Exporting selected feature directly as data file Right click on the layer in the TOC Right click on the layer in the TOC Data Data Export Data Export Data

Summary of.lyr file and data file.lyr file.lyr file Selected features are NOT saved in a new data file. Selected features are NOT saved in a new data file. A.lyr file stores symbology and labeling properties. A.lyr file stores symbology and labeling properties. Useful when you want to preserve the symbology for consistency. Useful when you want to preserve the symbology for consistency. Saves disk space Saves disk space Data file Data file Selected features are saved in a new data file (shapefile, geodatabase). Symbology information is not stored in the data file. Selected features are “permanently” saved. Better performance.