Given the current state of a diver's tissues,
this command calculates the diver's decompression ceiling:
the shallowest depth (or lowest ambient pressure) to which it is safe to
ascend.
The argument state gives the diver's current state
or the diver's progressive state during a dive.
It has typically been calculated using haldane.
It should be either:
A numeric vector giving the diver's current nitrogen tensions
for each tissue.
The length of the vector matches the number of tissues in
the model.
A matrix giving the diver's current nitrogen and (if present)
helium tensions for each tissue. The rows of the matrix correspond to
tissues in the model. The first column (or the column labelled
"N2") contains the nitrogen tensions, and if present, the second
column (or column labelled "He") contains the helium
tensions.
A three-dimensional array giving the progressive states of
the diver over time. The first index corresponds to time.
The second index corresponds to tissues in the model. The third
coordinate corresponds to inert gases "N2" and "He".
Entries in the vector, matrix or array state are pressures
in atmospheres absolute (ata).
The minimum tolerated ambient pressure Pamb.tol is calculated
using the equivalent of Buehlmann's formula (Buehlmann et al, 1995,
section 6.5, page 117). If what="pressure", this minimum
tolerated ambient pressure is returned (negative pressures are reset
to zero). If what="depth" this pressure is converted to
diving depth in metres assuming that the surface pressure is 1 ata
(negative depths are reset to zero).