# PLaSK User Manual

#### Page Contents

- VoltageProvider3D Class
  - `VoltageProvider3D`
  - `VoltageProvider3D.solver.outVoltage()`
  - Methods
  - Descriptions
    - Method Details
      - `VoltageProvider3D.__call__()`
      - `VoltageProvider3D.set_changed()`

# VoltageProvider3D Class

class plask.flow.VoltageProvider3D(data)

  Provider of the voltage in Cartesian3D geometry (V).

  This class is used for voltage provider in binary solvers. You can also create a custom provider for your Python solver.

  Parameters:

    data – `Data` object to interpolate or callable returning it for given mesh. The callable must accept the same arguments as the provider `__call__` method (see below).

  To obtain the value from the provider simply call it. The call signature is as follows:

  solver.outVoltage(mesh, interpolation='default')
    Parameters:

      - mesh (mesh) – Target mesh to get the field at.

      - interpolation (str) – Requested interpolation method.

    Returns:

      Data with the voltage on the specified mesh (V).

  Example

  Connect the provider to a receiver in some other solver:

      >>> other_solver.inVoltage = solver.outVoltage

  Obtain the provided field:

      >>> solver.outVoltage(mesh)
      <plask.Data at 0x1234567>

  See also

  Receiver of voltage: `plask.flow.VoltageReceiver3D` Data filter for voltage: `plask.flow.VoltageFilter3D`

## Methods

`__call__`(mesh[, interpolation]) | Get value from the provider.
`set_changed`() | Inform all connected receivers that the provided value has changed.

## Descriptions

### Method Details

VoltageProvider3D.__call__(mesh, interpolation='DEFAULT')

  Get value from the provider.

  Parameters:

    - mesh (mesh) – Target mesh to get the field at.

    - interpolation (str) – Requested interpolation method.

VoltageProvider3D.set_changed()

  Inform all connected receivers that the provided value has changed.

  The receivers will have its changed attribute set to True and solvers will call the provider again if they need its value (otherwise they might take it from the cache.