# ARTS built-in documentation server

## Workspace Method DoitInit

### Description

Initialises variables for DOIT scattering calculations. Note that multi-dimensional output variables (Tensors, specifically) are NaN-initialized. That is, this methods needs to be called BEFORE other WSMs that provide input to DoitCalc, e.g. before DoitGetIncoming.

**Authors: **Claudia Emde

### Synopsis

DoitInit( | doit_scat_field, cloudbox_field, doit_is_initialized, stokes_dim, atmosphere_dim, f_grid, za_grid, aa_grid, doit_za_grid_size, cloudbox_on, cloudbox_limits ) |

### Variables

OUT | doit_scat_field | (Tensor6) | Scattered field inside the cloudbox. |

OUT | cloudbox_field | (Tensor7) | The spectral radiance field inside the cloudbx. |

OUT | doit_is_initialized | (Index) | Flag to determine if DoitInit was called. |

IN | stokes_dim | (Index) | The dimensionality of the Stokes vector (1-4). |

IN | atmosphere_dim | (Index) | The atmospheric dimensionality (1-3). |

IN | f_grid | (Vector) | The frequency grid for monochromatic pencil beam calculations. |

IN | za_grid | (Vector) | Zenith angle grid. |

IN | aa_grid | (Vector) | Azimuthal angle grid. |

IN | doit_za_grid_size | (Index) | Number of equidistant grid points of the zenith angle grid. |

IN | cloudbox_on | (Index) | Flag to activate the cloud box. |

IN | cloudbox_limits | (ArrayOfIndex) | The limits of the cloud box. |