Description Usage Arguments Value Note Author(s) References See Also Examples

`angles`

computes the turning angles (in radians) between
consecutive moves from an object of class `traj`

. See examples
for a clearer definition.

1 2 |

`x` |
an object of class |

`id` |
a character vector giving the identity of the animals for which the angles are to be computed |

`burst` |
a character vector giving the identity of the circuits for which
the angles are to be computed (see |

`date` |
a vector of class |

`slsp` |
a character string. If |

Returns a data frame with the following components:

`id` |
the identity of the animal |

`x` |
the x coordinate of the relocation at which the angle is computed |

`y` |
the y coordinate of the relocation at which the angle is computed |

`date` |
a vector of class |

`burst` |
the id of the circuit (see |

`angles` |
the turning angles between the successive moves. |

The function `angles`

is deprecated. The class `ltraj`

computes the turning angles automatically (see `ltraj`

).

Clement Calenge [email protected]

Turchin, P. (1998) *Quantitative analysis of movement. Measuring
and modeling population redistribution in animals and plants.*
Sunderland, Massachusetts: Sinauer Associates.

`speed`

for computation of movement speeds,
`traj`

for additional information about objects of
class `traj`

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 | ```
## Not run:
## loads an object of class "traj"
data(puechcirc)
puechcir <- ltraj2traj(puechcirc)
puechcir
## Gets a part of the trajectory of the wild boar named
## CH93 and draws it
## Also displays the turning angles
toto <- puechcir[2:5,]
plot(toto$x, toto$y, asp = 1, ylim = c(3158300, 3158550),
pch = 16,
main = "Turning angles between\nthree consecutive moves",
xlab="X", ylab="Y")
lines(toto$x, toto$y)
lines(c(toto$x[2], 700217.6),
c(toto$y[2], 3158310), lty=2)
lines(c(toto$x[3],700289),
c(toto$y[3],3158546), lty=2)
ang1x <- c(700234.8, 700231.9, 700231, 700233.7, 700238.8, 700243.2)
ang1y <- c(3158332, 3158336, 3158341, 3158347, 3158350, 3158350)
ang2x <- c(700283.3, 700278.8, 700275.4, 700272.4, 700271.2, 700271.6,
700274.7)
ang2y <- c(3158522, 3158522, 3158520, 3158517, 3158514, 3158508, 3158504)
lines(ang1x, ang1y)
lines(ang2x, ang2y)
text(700216.1, 3158349, expression(theta[1]), cex=2)
text(700247.7, 3158531, expression(theta[2]), cex=2)
text(c(700301, 700231), c(3158399, 3158487),
c("Beginning", "End"), pos=4)
## Computation of the turning angles with real data
## on wild boars
plot(puechcir)
ang <- angles(puechcir)
## The angles are in the column angles:
ang[1:4,]
## End(Not run)
``` |

Embedding an R snippet on your website

Add the following code to your website.

For more information on customizing the embed code, read Embedding Snippets.