File formats

Such a file, whose extension is usually `.pers`

, contains a list of persistence intervals.

Lines starting with `#`

are ignored (comments).

Other lines might contain 2, 3 or 4 values (the number of values on each line must be the same for all lines):

[[field] dimension] birth death

Here is a simple sample file:

# Persistence diagram example 2 2.7 3.7 2 9.6 14. # Some comments 3 34.2 34.974 4 3. inf

Other sample files can be found in the `data/persistence_diagram`

folder.

Such files can be generated with `Gudhi::persistent_cohomology::Persistent_cohomology::output_diagram()`

and read with `Gudhi::read_persistence_intervals_and_dimension()`

, `Gudhi::read_persistence_intervals_grouped_by_dimension()`

or `Gudhi::read_persistence_intervals_in_dimension()`

.

Such a file describes an iso-oriented cuboid with diagonal opposite vertices (min_x, min_y, min_z,...) and (max_x, max_y, max_z, ...). The format is:

min_x min_y [min_z ...] max_x max_y [max_z ...]

Here is a simple sample file in the 3D case:

-1. -1. -1. 1. 1. 1.

This file format is the format used by the Perseus software (http://www.sas.upenn.edu/~vnanda/perseus/) by Vidit Nanda. The first line contains a number d begin the dimension of the bitmap (2 in the example below). Next d lines are the numbers of top dimensional cubes in each dimensions (3 and 3 in the example below). Next, in lexicographical order, the filtration of top dimensional cubes is given (1 4 6 8 20 4 7 6 5 in the example below).

The input file for the following complex is:

2 3 3 1 4 6 8 20 4 7 6 5

To indicate periodic boundary conditions in a given direction, then number of top dimensional cells in this direction have to be multiplied by -1. For instance:

2 -3 3 1 4 6 8 20 4 7 6 5

Indicate that we have imposed periodic boundary conditions in the direction x, but not in the direction y.

Other sample files can be found in the `data/bitmap`

folder.

GUDHI Version 2.1.0 - C++ library for Topological Data Analysis (TDA) and Higher Dimensional Geometry Understanding. - Copyright : GPL v3 | Generated on Fri Feb 2 2018 14:51:32 for GUDHI by Doxygen 1.8.11 |