Need option to calculate ocean transports across latitudes for a single ocean basin (via mask)

[gaelforget]

No description provided.

[gaelforget]

• For reference the Matlab/Octave implementation for this is https://github.com/MITgcm/gcmfaces/blob/0b9132b739bb88c07de9398ffbda09505ba25d83/gcmfaces_diags/diags_set_A.m#L65
• In MeshArrays.jl we might instead pass the mask to ThroughFlow via a keyword argument :
  ThroughFlow(VectorField,IntegralPath,Γ::NamedTuple; mask=[])
• And then if !isempty(msk) then multiply both U,V by this mast @

  MeshArrays.jl/src/Operations.jl

  Line 268 in 22241b1

  U=VectorField["U"]

  ,

  MeshArrays.jl/src/Operations.jl

  Line 269 in 22241b1

  V=VectorField["V"]

[gaelforget]

MSK=(isempty(msk) ? 1.0 : msk)
U=MSK .*VectorField["U"] 
V=MSK .*VectorField["V"]