geoSR: Plot Squares in Different Colors

In geo: Draw and Annotate Maps, Especially Charts of the North Atlantic

Description

Plot Icelandic statistical squares in different colors, based on specified levels.

Usage

geoSR(sr, z, levels, grid = FALSE, ...)

Arguments

sr	squares or subsquares.
z	values for each square.
levels	threshold levels for splitting the values into categories.
grid	passed to geoplot.
...	passed to geoplot.

Details

If levels is a named vector, the names are used as level-specific colors, ignoring the last element.

The levels should go lower and higher than the range of z values.

Value

Invisible NULL.

Note

Convenience wrapper for the reitaplott function.

The 3-digit Icelandic statistical squares are 0.5 degrees latitude and 1 degree longitude, defined in the range 60–70<c2><b0>N and 0–50<c2><b0>W.

The bottom-left corner of square 0 is at 60<c2><b0>N 0<c2><b0>. From there, the numbering system is best explained with a table:

	49<c2><b0>W	48<c2><b0>W	...	1<c2><b0>W	0<c2><b0>W
69.5<c2><b0>N	999	998	...	951	950
69.0<c2><b0>N	949	948	...	901	900
...	...	...	...	...	...
60.5<c2><b0>N	099	098	...	051	050
60.0<c2><b0>N	049	048	...	001	000

The 4-digit subsquares divide each square into quadrants (NW, NE, SW, SE), appending a number to indicate the quadrant:

***1	***2
***3	***4

Author(s)

Arni Magnusson.

See Also

geoplot and reitaplott are the underlying drawing functions.

colorRampPalette can be used to create a ramp of level-specific colors.

Examples

# Use existing palette
geoSR(561:560, c(0.3,3), levels=c(0,1,10))

# Pass colors along with levels
lev <- c(0, 1, 10)
names(lev) <- c("brown", "orange", NA)
geoSR(561:560, c(0.3,3), lev)

# Subsquares
geoSR(5611:5612, c(0.3,3), lev)

# Color ramp
z <- (0:10) / 10
lev <- (0:10) / 10
ramp <- colorRampPalette(c("khaki1","gold","orange","darkorange2","red",
                           "darkred","black"))
names(lev) <- ramp(length(lev))
geoSR(724:715, z, lev)

Example output

Loading required package: maps
Loading required package: mapdata

geo documentation built on May 29, 2017, 5:36 p.m.