Raster and RBuilding and Visualizing

What is Raster Data?

• A rectangular grid containing pixels.

• Each pixel contains a value

• Value is represented by a color.

Raster space-time plots• Raster Stacks & Bricks

• Multidimensional raster objects• Multi-layer (red,green,blue)• Multi-dim (time series, multi variable)

X

YZ

stack[row# ,col#, Z#]

Raster space-time plots• Multi-dimentional Raster Stack

• Good for time-series of rasters, or multivariate analysis

Time Seriesstack[x,y, c(cwd2010) ]

Y

XCWD 2010

By Month

Setup Raster Stack Data Helpful Functions

dir(‘your//Data//Location’)

grep()

grep(‘a’, c( ‘a’, ‘b’, ‘c’, ‘a’ ) )dir()

grep(‘c’, c( ‘tab’, ‘car’, ‘bat’ ) )

Create Raster Stacks and Assign Name LabelsHelpful

Functions

paste(c(‘Jan',‘Feb', ‘Mar‘...), sep=' ')

paste() names()names(rstack) = c(Jan’,’Feb’)

Jan

Feb

Y

X

Sources• Information for the Raster package from

cran created by Robert Hijmans• RasterVis package Github created by

Oscar Lamiguero.• And Mike Mann in Geography Department