# ARTS built-in documentation server

## Workspace Method jacobianCalcFreqStretch

### Description

Calculates frequency stretch jacobians by interpolation of iyb. This function is added to jacobian_agenda by jacobianAddFreqStretch and should normally not be called by the user.

**Authors: **Patrick Eriksson

### Synopsis

jacobianCalcFreqStretch( | jacobian, mblock_index, iyb, yb, stokes_dim, f_grid, mblock_dlos, sensor_response, sensor_response_pol_grid, sensor_response_f_grid, sensor_response_dlos_grid, jacobian_quantities ) |

### Variables

OUT+IN | jacobian | (Matrix) | The Jacobian matrix. |

IN | mblock_index | (Index) | Measurement block index. |

IN | iyb | (Vector) | Monochromatic pencil beam data for one measurement block. |

IN | yb | (Vector) | The measurement vector for a single measurement block. |

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

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

IN | mblock_dlos | (Matrix) | The set of angular pencil beam directions for each measurement block. |

IN | sensor_response | (Sparse) | The matrix modelling the total sensor response. |

IN | sensor_response_pol_grid | (ArrayOfIndex) | The "polarisation grid" associated with sensor_response. |

IN | sensor_response_f_grid | (Vector) | The frequency grid associated with sensor_response. |

IN | sensor_response_dlos_grid | (Matrix) | The zenith and azimuth angles associated with sensor_response. |

IN | jacobian_quantities | (ArrayOfRetrievalQuantity) | The retrieval quantities in the Jacobian matrix. |