`R/AllometricFunctions.R`

`proportion_silhouette_area_shapes.Rd`

The function estimates the projected (silhouette) area as a portion of the surface area of the organism. The function estimates the projected area as a function of the dimensions and the angle between the solar beam and the longitudinal axis of the solid, using Figure 11.6 in Campbell and Norman (1998) . The function is useful for estimating absorbed solar radiation.

`proportion_silhouette_area_shapes(shape, theta, h, d)`

- shape
`character`

Shape to use to approximate an organism. Shapes are assumed to be prolate or have the longest axis parallel with the ground. Current choices are`"spheroid"`

,`"cylinder flat ends"`

, and`"cylinder hemisphere ends"`

.- theta
`numeric`

angle between the solar beam and the longitudinal axis (degrees).- h
`numeric`

height (long axis in m). Cross section length for spheroid.- d
`numeric`

diameter (short axis in m). Cross section length for spheroid.

`numeric`

silhouette area as a proportion.

Campbell GS, Norman JM (1998).
*Introduction to environmental biophysics*, 2nd ed. edition.
Springer, New York.
ISBN 0387949372.

Other allometric functions:
`mass_from_length()`

,
`proportion_silhouette_area()`

,
`surface_area_from_length()`

,
`surface_area_from_mass()`

,
`surface_area_from_volume()`

,
`volume_from_length()`

```
proportion_silhouette_area_shapes(shape = "spheroid",
theta = 60,
h = 0.01,
d = 0.001)
#> [1] 0.2748564
proportion_silhouette_area_shapes(shape = "cylinder flat ends",
theta = 60,
h = 0.01,
d = 0.001)
#> [1] 0.2744423
proportion_silhouette_area_shapes(shape = "cylinder hemisphere ends",
theta = 60,
h = 0.01,
d = 0.001)
#> [1] 0.2733313
```