- Handlers were added in
`add_observations()`

for situations where observations are projected at the same location, specifically for the`duplicated_strategy`

argument. - A
`simulate`

method was added for`graph_lme`

objects. - The possibility of fixing parameters during estimation was added.
- The
`Spoints`

argument in`add_observations()`

has been deprecated. Now,`SpatialPointsDataFrame`

can be added directly in the`data`

argument. `sf`

objects containing data can also be directly added using the`add_observations()`

method in the`data`

argument.- The option of using a
`graph_lme`

object to provide starting values when fitting a model using`graph_lme()`

was added. - The option of fitting a directional Whittle-Matérn model with
`alpha=1`

when using`graph_lme()`

was added. - The
`kirchhoff_weights`

argument was added to obtain weights for Kirchhoff vertex conditions from`edge_weights`

. - Handling of edge weights was improved. For example, if pruning changes any edge weight, a warning will be given.
- The
`edgeweight_to_data()`

method was added to turn edge weights into data in the internal metric graph format. `edge_weight`

and`edge_width_weight`

were added to the`plot()`

method so that plots on metric graphs can be produced with the weights providing colors to the edges, and also with (possibly different) weights providing the thickness of the edges.`edge_weights`

were added to`graph_components`

so that the connected components will have the correct corresponding edge weights.`edge_weight`

and`edge_width_weight`

were added to the`plot_function()`

method, where they work in a similar manner to their counterparts for the`plot()`

method. The difference is that the weights are plotted as piecewise constant functions.- The
`prune_vertices`

now has an option to not prune vertices whose edges have incompatible edge weights. - The
`plot`

method has an`interactive`

argument that returns the 2D plot as a plotly object, which is interactive when using`ggplotly`

. - The dependency on the
`viridis`

package has been removed.

- Changed argument
`data`

to`newdata`

in`predict`

methods. The argument`data`

was deprecated. - Bugfixes on sample_spde and when adding observations based on Euclidean positions.
- Added options
`vertex_unit`

and`length_unit`

on graph creations. Units are given in edge lengths with the`get_edge_lengths()`

method. - Added a method to check if the graph is a tree.
- The graph construction was thoroughly refactored. The resulting construction is faster and cleaner.
- The graph constructions now accepts list of coordinates (where the coordinates are given as either matrices or data frames),
`SpatialLines`

,`SpatialLinesDataFrames`

or`MULTILINESTRING`

. - Adding two options (
`sf`

package or`sp`

package) for handling`longlat`

by using the`which_longlat`

option. - Adding
`crs`

(if using`sf`

) and`proj4string`

(if using`sp`

) for handling general coordinate reference systems. - Moving
`data`

to the`private`

environment. - Several data manipulation helper tools and methods were introduced, together with a vignette with a brief tutorial on these tools.
- The method
`mesh_A()`

has been deprecated, use`fem_basis()`

instead. - Several quality of life improvements.
- Improved the
`plot()`

method with the option`plotly=TRUE`

. - Improved the
`plot_function()`

method to accept`data`

and`newdata`

. - Included a
`process_data()`

method for metric graphs - Renamed the data internal structure from "__group“,”__edge_number“,”__distance_on_edge“,”__coord_x“,”__coord_y" to “.group”, “.edge_number”, “.distance_on_edge”, “.coord_x” and “.coord_y”.
- Added an “advanced grouping” option, in which the group variable can be a combination of several columns.
- Improved graph_lme() behavior to avoid having NaN as std.errors.
- Added check for distance consistency and, more generally, check to see if the graph has euclidean edges.
- Added method
`get_groups()`

to get the unique groups, and also to retrieve the columns that were used to create the group variable. - Added the
`get_data()`

method to get the data in a user-friendly manner. - Added
`glance()`

and`augment()`

methods for`graph_lme()`

objects. - Added
`get_vertices_incomp_dir()`

method to return vertices with incompatible directions. - Added
`print()`

,`summary()`

,`compute_characteristics()`

,`check_euclidean()`

,`check_distance_consistency()`

methods. - Added support for edge weights.
- Created
`vertices`

element in the metric graph object, containing information such as degrees, indegrees, outdegrees. - Created
`print`

methods for`edges`

,`vertices`

, and for their entries. - Added the
`improve_plot`

option on`plot_function`

. - Added support for discontinuous meshes (at the vertices).
- Added support for discontinuous functions (at the vertices) for
`plot_function()`

.

- Adjusts to ensure compatibility with future releases of the Matrix package.

- Adjusts on documentation for CRAN.

- Improved the documentation.
- Reorganized some functions.

- First version of the package.