r.SDE: Demo Data: Standard Deviation Ellipse Output Object

Description Usage Format Details Source Examples

Description

Results from the Standard Deviation Ellipse Calculator (calc_sde) are stored in a list object. This object is required for the plot function (plot_sde).

Usage

1

Format

The list object contains the following results:

id

Identifier for the SDE estimate - it should be unique

points

a simple two-column data frame (or matrix) containing x,y coordinates for a series of point locations.

coordsSDE

coordsSDE value, coordinates of the SDE

calccentre

Boolean: TRUE if mean centre is computed

CENTRE.x

X-coordinate of the centre

CENTRE.y

Y-coordinate of the centre

Sigma.x

Half-length of axis along x-axis

Sigma.y

Half-length of axis along y-axis

Major

String indicating which axis is the major elliptical axis

Minor

String indicating which axis is the minor elliptical axis

Theta

Rotation angle in degrees

Eccentricity

A measure of eccentricity (i.e., the flatness of the ellipse)

Area.sde

Area of the SDE

TanTheta

Trigonometric result

SinTheta

Trigonometric result

CosTheta

Trigonometric result

SinThetaCosTheta

Trigonometric result

Sin2Theta

Trigonometric result

Cos2Theta

Trigonometric result

ThetaCorr

Corrected theta angle for rotation of major axis from north

weighted

Boolean: TRUE if the weighted mean centre is to be used instead

weights

Weights applied to point observations

Details

The coordinates of the points must have the same units and projection as the specified center.

Source

This demonstration data has been manufactured for illustrative purposes only.

Examples

1
2

Example output

Loading required package: splancs
Loading required package: sp

Spatial Point Pattern Analysis Code in S-Plus
 
 Version 2 - Spatial and Space-Time analysis

Loading required package: Hmisc
Loading required package: lattice
Loading required package: survival
Loading required package: Formula
Loading required package: ggplot2

Attaching package: 'Hmisc'

The following object is masked from 'package:splancs':

    zoom

The following objects are masked from 'package:base':

    format.pval, round.POSIXt, trunc.POSIXt, units

Loading required package: shapefiles
Loading required package: foreign

Attaching package: 'shapefiles'

The following objects are masked from 'package:foreign':

    read.dbf, write.dbf

List of 22
 $ id              : num 1
 $ points          :'data.frame':	10 obs. of  9 variables:
  ..$ x   : num [1:10] 617816 611320 606329 620688 612836 ...
  ..$ y   : num [1:10] 4837974 4827947 4826776 4839942 4828455 ...
  ..$ x2  : num [1:10] 3.82e+11 3.74e+11 3.68e+11 3.85e+11 3.76e+11 ...
  ..$ y2  : num [1:10] 2.34e+13 2.33e+13 2.33e+13 2.34e+13 2.33e+13 ...
  ..$ x'  : num [1:10] 6875 379 -4612 9747 1895 ...
  ..$ y'  : num [1:10] 7137 -2891 -4062 9104 -2382 ...
  ..$ x'2 : num [1:10] 47264388 143649 21272297 95000305 3591442 ...
  ..$ y'2 : num [1:10] 50936484 8355106 16498382 82891556 5674496 ...
  ..$ x'y': num [1:10] 49066095 -1095536 18733886 88739637 -4514379 ...
 $ coordsSDE       : num [1:360, 1:2] 619582 619454 619303 619130 618938 ...
 $ calccentre      : logi TRUE
 $ CENTRE.x        : num 610941
 $ CENTRE.y        : num 4830837
 $ Major           : chr "SigmaY"
 $ Minor           : chr "SigmaX"
 $ theta           : num 52.4
 $ Sigma.x         : num 3603
 $ Sigma.y         : num 10901
 $ Eccentricity    : num 0.944
 $ Area.sde        : num 1.23e+08
 $ TanTheta        : num 1.3
 $ SinTheta        : num 0.793
 $ CosTheta        : num 0.61
 $ SinThetaCosTheta: num 0.483
 $ Sin2Theta       : num 0.628
 $ Cos2Theta       : num 0.372
 $ ThetaCorr       : num 52.4
 $ weighted        : logi FALSE
 $ weights         : NULL

aspace documentation built on May 2, 2019, 6:24 a.m.