An ASCII format that contains the same amount of information as NDskl files, but organized in a different way. In particular, filaments are not described as lists of segments but rather each filament is described by an origin node, a destination node, and a set of sampling points.

ANDSKEL | header |
---|---|

ndims | the number of dimensions |

#comments go here | OPTIONAL: should start with '#' if present (the 80 first characters are read and stored). |

BBOX [x0_1 .. x0_d] [delta_1 .. delta_d] | OPTIONAL: the bounding box, defined by the 'ndims' coordinates of the origin 'x0' and extent 'delta'. |

[CRITICAL POINTS] | Marks the beginning of the critical points section |

ncrit | The number of critical points (CP) |

type pos[0] ... pos[ndims-1] value pairID boundary | Info on the first CP: critical index, position, value, index of CP in the persistence pair, 0 if not on the boundary |

nfil | The number of filaments connected to this CP |

destId[0] filId[0] | Info on the first filament: index of the CP at the other extremity of the filament, and index of the filament (see filaments table below) |

... | One line for each filament connecting on the CP |

destId[nfil-1] filId[nfil-1] | Information on the last filament |

..... | |

..... | one blue block for each CP. |

..... | |

[FILAMENTS] | Marks the beginning of the filaments section |

nfil | Total number of filaments |

CP1 CP2 nSamp | index of the CP at the extremity of the first filament and number of sampling points |

P[0][0] ... P[0][ndims-1] | position of the first sampling point of first filament. |

... | One line for each sampling point of first filament. |

P[nSamp-1][0] ... P[nSamp-1][ndims-1] | Position of the last sampling point |

..... | |

..... | one blue block for each filament. |

..... | |

[CRITICAL POINTS DATA] | Marks the beginning of the CP data section |

NF | Number of fields associated to each CP. |

CP_DATA_FIELD_NAME_1 | Name of the first field |

... | |

CP_DATA_FIELD_NAME_NF | Name of the last field |

val_1[0] ... val_NF[0] | Value of each field for first CP |

... | |

val_1[N_CP-1] ... val_NF[N_CP-1] | Value of each field for last CP |

[FILAMENTS DATA] | Marks the beginning of the filaments data section |

NF | Number of fields associated to each sampling point of each filament. |

FIL_DATA_FIELD_NAME_1 | Name of the first field |

... | |

FIL_DATA_FIELD_NAME_NF | Name of the last field |

val_1[0][0] ... val_NF[0][0] | field values for first sampling point, first filament |

... | |

val_1[0][nSamp[0]] ... val_NF[0][nSamp[0]] | field values for last sampling point, first filament |

..... | |

..... | one blue block for each filament. |

..... |