getTrac {tracheideR}

Compute tracheidograms

Description

This function computes a tracheidogram from microscope light measurements in gray (0-255).

Usage

getTrac(x, val50 = 120, mw = 5, scale = 1)

Arguments

x

a vector with the light measurements (pixel gray-level values)

val50

the value giving the "intensity" of the light measurements at which the measurments should be made (for more details please see the help of tgram function).

mw

width of the rolling window to smooth the original data (for more details please see the help of tgram function)

scale

distance per pixel, default = 1

Details

This function uses the tgram function (tgram package) to convert gray pixel values (0-255) into a raw tracheidogram (keeping the original number of cells).

Value

getTrac returns a list with following elements:

n number of cells

pos pos$RingWidth gives the tree-ring width and pos$x gives the "position" of each tracheid.

LD a vector with the lumen diameter (LD).

CWT a vector with the radial cell wall thikness (CWT).

LWratio a vector with the LD/CWT ratio.

References

DeSoto, L., De la Cruz, M., Fonti, P. (2011). Intra-annual patterns of tracheid size in the Mediterranean tree Juniperus thurifera as an indicator of seasonal water stress. Canadian Journal of Forest Research 41: 1280-1294. Vaganov, E., 1989. The tracheidogram method in tree-ring analysis and its application, in: Cook, E., Kairiukstis, L. (Eds.), Methods of Dendrochronology: Applications in the Environmental Sciences. Kluwer Academic Publishers, Dordrecht, The Netherlands.

See Also

tgram

Examples

## Not run:
y2010ray1 <- getTrac(tch$y2010$ray1, scale = 0.169)
y2010 <- getTrac(tch$y2010, scale = 0.169)
TCH <- lapply(tch,getTrac, scale = 0.169)
TCH$y2010$ray1$n #number of tracheids in ray1 in the year 2010
TCH$y2010$ray1$pos$RingWidth #number of tracheids in ray1 in the year 2010
#getTrac(tch$y2010$ray2, scale = 0.169)
#getTrac(data.frame(tch$y2010$ray2), scale=0.169)
## End(Not run)