YplantQMC (version 0.6-6)

evalHemi: Generate a hemiphoto object

Description

Construct an object that contains information on shading by the canopy, as measured with hemi-spherical photographs ('hemiphotos'). Reads one of two formats. See YplantQMC website for example files, and the instruction manual for more background.

Usage

evalHemi(hemi, altitude = NULL, azimuth = NULL, met = NULL, degrees = TRUE)
"plot"(x, met = NULL, sungap = TRUE, projection = c("iso", "flat"), warn = TRUE, bordercol = "black", ...)
setHemi(canfile, canopytrans = 0.02)

Arguments

hemi

An object generated with setHemi.

altitude, azimuth

Viewing altitude and azimuth.

met

Optionally, a ypmet object.

degrees

Whether altitude and azimuth were given in degrees (if FALSE, radians).

x

For plot.yphemi, a yphemi object

sungap

If TRUE, and a ypmet object is used, plots the sun along the path, with the size relative to the gap fraction

projection

If 'iso', each altitude bin has the same width in the plot (Default). If 'flat', projection is as seen from above.

warn

If TRUE and sungap=TRUE, warns when gap fractio is very low.

bordercol

Color of the grid separating the sky sectors. Use NA to omit borders.

canfile

A canopy file (see Vignette for format example).

canopytrans

Minimum transmission of canopy (when gap fraction = 0).

...

Further arguments passed to plot.default

References

For background on hemiphotos : http://en.wikipedia.org/wiki/Hemispherical_photography

See Also

setMet