Hi,
can a knowledgeable person please comment on whether I am using the
"cell_methods" and "cell_bounds" attributes correctly in the example below? In
particular, is my understanding correct that the cell_methods are attributed
to the data variable, whereas the cell_bounds are attributed to the coordinate
variable?
Also, is there a standard name suitable for expressing an acoustic travel time
from an underwater echo sounder signal? The device literally reports a time
(in seconds) of how long it took the echo to travel to its target and back. I
am against reporting it as an average sound speed because the distance to the
target might not be known with high accuracy, leaving me with two unknowns
(sound speed and distance). The travel time itself is the quantity of
interest.
Thanks, Matt L.
My first shot at cell methods:
Dimensions:
TIME=100
DEPTH=1
AUX=2
Data variable:
VATT(TIME,DEPTH)
VATT:long_name="vertical acoustic travel time"
VATT:units="s"
VATT:cell_methods="TIME: point DEPTH: sum"
Coordinate variable:
DEPTH(DEPTH) % here: one depth only, 3500m
DEPTH:units="m"
DEPTH:cell_bounds="AUX_DEPTH_BOUNDS"
Auxiliary variable:
AUX_DEPTH_BOUNDS(AUX)=0,3500;
So... the cell_bounds are given as an attribute to DEPTH, and point to yet
another variable (of length DEPTH+1) that actually contains the values.
Or can I just write the values into the attribute to DEPTH:
DEPTH:cell_bounds=0,3500;
--
_______________________________________
Dr. Matthias Lankhorst
Scripps Institution of Oceanography
9500 Gilman Drive, Mail Code 0230
La Jolla, CA 92093-0230
USA
Phone: +1 858 822 5013
Fax: +1 858 534 9820
E-Mail: mlankhorst at ucsd.edu
http://www-pord.ucsd.edu/~mlankhorst/
Received on Fri May 11 2012 - 17:50:09 BST
