NeumannValue

NeumannValue[val, pred] represents a Neumann boundary value val, specified on the part of the boundary of the region given to NDSolve and related functions where pred is True.

Examples

NDSolve[{Laplacian[u[x, y], {x, y}] == 0, 
  NeumannValue[1, x == 0], DirichletCondition[u[x, y] == 0, x == 1]}, 
  u, {x, 0, 1}, {y, 0, 1}]

NeumannValue[0, y == 0 || y == 1]

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