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NDSolve::bcnan NDSolveValue::bcnan ParametricNDSolve::bcnan ParametricNDSolveValue::bcnan

NDSolve::bcnan NDSolveValue::bcnan ParametricNDSolve::bcnan ParametricNDSolveValue::bcnan

Details

  • This message is generated when the boundary conditions in a boundary value problem are not properly specified.
  • Off[message] switches off the message; On[message] switches it on. For example: Off[NDSolve::bcnan].

Examples

Basic Examples  (2)

An error occurs because one of the boundary conditions involves the variable of the differential equation. is causing the problem since is the independent variable in the equation:

Wolfram Language code: NDSolve[{f''[x] + f[x] == 0, f[1] == x, f[2] == 1}, f, {x, 1, 2}]

This shows a valid specification of a boundary value problem:

Wolfram Language code: NDSolve[{f''[x] + f[x] == 0, f[1] == 1, f[2] == 1}, f, {x, 1, 2}]

An error occurs because a parameter in one of the boundary conditions does not have a numerical value:

Wolfram Language code: NDSolve[{f''[x] + f[x] == 0, f[0] == 0, b f[1] == 1}, f, {x, 0, 1}]

This shows a valid specification of the solution of a boundary value problem:

Wolfram Language code: Block[{b = 2}, NDSolve[{f''[x] + f[x] == 0, f[0] == 0, b f[1] == 1}, f, {x, 0, 1}]]