Many NA values when extracting data from a RasterLayer onto SpatialPolygons

How to extract raster values to polygon in R?

These are the main steps in the process:

1. Load raster and polygon data.
2. Mask and crop the raster layer.
3. Subset the multipolygon feature collection.
4. Extract the underlying raster values for each feature in the polygon layer.

How to extract pixel values from raster in R?

Extract Raster Values from Points using R

1. Step 1: Create a Raster stack or Raster brick of your raster files using “raster” package in R.
2. Step 2: Read point data, and convert them into spatial points data frame.
3. Step 3: Extract raster value by points.
4. Step 4: Combine raster values with point and save as a CSV file.

How do I extract data from raster?

Use the Extract Data tool to extract and download feature data using an area of interest. Use the Clip raster function to clip a raster to a specified extent or boundary layer.

Can raster data be a shapefile?

A shapefile cannot contain an attribute field to hold raster datasets. In this case, you need to use a hyperlink. The following are the general steps to add a raster dataset to a field within a feature class: Add a field of type Raster to the attribute table.

How do I extract raster values in ArcGIS pro?

The Extract Values to Points tool extracts the cell values of a raster and creates a new point feature class. In ArcGIS Pro, click the Analysis ribbon, and click the Tools icon. In the Geoprocessing pane, search for and click Extract Values to Points.
 

How do I extract pixel values from raster in ArcMap?

Procedure

1. In ArcMap, click the Search icon and search for Extract Values to Points (Spatial Analyst).
2. In the Extract Values to Points dialog box, configure as follows: For Input point features, select the point layer. In this example, it is Stations_SW_LA. For Input raster, select a raster layer.

How do I extract the pixels of an image?

The procedure for extraction is :

1. import the Image module of PIL into the shell: >>>from PIL import Image.
2. create an image object and open the image for reading mode: >>>im = Image.open(‘myfile.png’, ‘ r’)
3. we use a function of Image module called getdata() to extract the pixel values.

How do you extract values from a vector?

Extracting a subset of values from the front or rear of a vector is a common task and the base functions head() and tail() can do this. The infix functions in the extractors group mimic some of this behaviour and add the ability to extract from – to, or, up -and-untill, a specific value.
 

Can you intersect a raster with a polygon?

Summary. It is sometimes necessary to determine the areas where the attributes of a raster layer intersect a polygon layer. In studies involving multiple attributes and covering massive acres of land, the intersecting areas may provide helpful information.
 

How do you vectorize raster data?

Vectorization: Convert Raster to Vector



Double-click the tool and select the raster that you want to convert to vector. From here, you’ll have to select the output of the raster to a point, line or polygon. After clicking “Run”, the vectorized raster will appear in the table of contents.
 

How do I extract a specific element from a vector in R?

Vectors are basic objects in R and they can be subsetted using the [ operator. The [ operator can be used to extract multiple elements of a vector by passing the operator an integer sequence.