order of vector shouldn't matter for calculations

[jordansread]

schmidt.stability(wtr=c(30,10),depths=c(0,10),bthA=c(100,2),bthD=c(0,10))
         [,1]
[1,] 119.3527

schmidt.stability(wtr=c(10,30),depths=c(10,0),bthA=c(100,2),bthD=c(0,10))
              [,1]
[1,] -2.658799e-11

very different answer because the order of the depths was switched around. Still should yield the same result.

[jordansread]

One way to deal with this is to require depths to be a monotonically increasing vector (error when it is not?)

[lawinslow]

If its out of order, could we just order the data first thing in the function? Might take roughly the same amount of time as checking.

Also, does this order issue affect other functions? Could check and sort in the other functions as well if yes.

[markbfernandez]

This also affects thermo.depth().