# eulerr 7.0.0

## New Features

- It is now possible to set the loss function to be used when trying to
  optimize the Euler diagram layout via `loss` and `loss_aggregator`.
  There is a new vignette that showcases this new feature.

## Minor Changes

- C++14 is now required for the package.

## Bug Fixes

- Label repelling via `adjust_labels` in `plot.euler()` has been
  deprecated and removed to fix sanitizer warnings. 

# eulerr 6.1.1

## Minor changes

- citation to conference paper added to `inst/CITATION`
- error messages for erroneous input have been improved in several places
- switched `PI` to `M_PI` to support `STRICT_R_HEADERS` in C++ code
  (#82, thanks @eddelbuettel)

## Bug fixes

- error in documentation for list method has been fixed, thanks @gprezza (#77)

# eulerr 6.1.0

## Minor changes

- Label repelling (activated by calling `euler()` with `adjust_labels = TRUE`)
  no longer repels text labels away from the edges of the shapes in
  the diagram.

## Bug fixes

- Rectify sanitizer error from clang-ASAN test environment.

# eulerr 6.0.2

## Bug fixes

- Set `stringsAsFactors = TRUE` inside all relevant functions in `euler()`
  to avoid errors in upcoming R version.
- Fix broken link in _eulerr under the hood_ vignette.

# eulerr 6.0.1

## Minor changes

- Throw an error message when the number of sets in `venn()` exceeds 5 (#65)
- Performance improved when large lists are used as input to `euler()` and
  `venn()` (#64, @privefl)

## Bug fixes

- Correctly handle `data.frame` inputs to `euler()` when categorical
  variables are character vectors and not factors.

# eulerr 6.0.0

## New features

- In `plot.euler()`, percentages can be added to the plot in addition to or
  instead of counts by providing a `list` to the `quantities` argument
  with an item `type` that can take any combination of `counts` and `percent`.
  This change also comes with a redesign of the grid graphics
  implementation for labels.
- `eulerr_options()` gains a new argument
  `padding` which controls the amount of padding between labels and quantities.
  (#48)
- `plot.euler()` now uses code from the **ggrepel** package to prevent
  labels from overlapping or escaping the plot area if `adjust_labels` is
  set to `TRUE`.
- A new vignette featuring a gallery of plots from the package has been
  added.

## Minor changes

- The default `cex` for quantity labels has changed from 1.0 to 0.9.
- Labels for sets that overlap are now merged (partly fixes #45)
- The fill colors for sets which are completely contained within another set
  are now once again composed of a mix of the color of the subset and
  the superset.
- Plotting data has been exposed in a `data` slot in the object created
  by calling to `plot.euler()` (#57)

## Bug fixes

- An error in layout normalization that occurred sometimes
  with ellipses has been fixed.

# eulerr 5.1.0

## New features

- `venn()` is a new function that produces Venn diagrams for up to
  5 sets. The interface
  is almost identical to `euler()` except that a single integer
  can also be provided. A new vignette, _Venn diagrams with eulerr_,
  exemplifies its use.

## Minor changes

- Calculations for the strips in `plot.euler()` when a list of
  Euler diagrams is given has been improved. Setting `fontsize` or
  `cex` now results in appropriately sized strips as one would expect.
- Tiny overlaps (where the fraction of the area is less than one
  thousandth of the largest overlap) in the final diagram are no longer
  plotted.
- `eulergram()` objects from `plot.euler()` now have a proper grob name
  for the canvas grob, so that extracting information from them is easier.

## Bug fixes

- Return value documentation for `euler()` now correctly says "ellipses"
  and not "coefficients".
- `data.frame` or `matrix` inputs now work properly
  when values are numerical. (#42)
- Fixed some spelling errors in news and vignettes.

# eulerr 5.0.0

## New features

- `error_plot()` is a new function that offers diagnostic plots of
  fits from `euler()`, letting the user visualize the error in the
  resulting Euler diagram.

## Major changes

- `euler()` once again uses the residual sums of squares, rather than the
  stress metric, as optimization objective, which means that
  output is always scaled appropriately to input (#28).
- `plot.euler()` now uses the
  [polylabelr](https://CRAN.R-project.org/package=polylabelr) package to
  position labels for the overlaps of the ellipses, which has improved
  performance in plotting complicated diagrams considerably and reduced the
  amount of code in this package greatly.
- The c++ internals have been rewritten using more memory-efficient, performant
  and expressive code.

## Minor changes

- The `euler.data.frame()` method (and by proxy the `euler.matrix()` method)
  can now take matrices with factors in addition to the previously supported
  logical and integer (binary) input. The function will dummy code the variables
  for the user.
- A few performance fixes.
- Additional unit tests.
- Previously deprecated arguments to `plot.euler()` have been made defunct.
- Added a data set, `plants`, to exemplify the list method for `euler()`.
- Added a data set, `fruits`, to exemplify the data.frame method for `euler()`.
- `euler.data.frame()` gains an argument `sep`, which is a character vector
  used to separate dummy-coded factors if there are factors or characters in the
  input.
- Added a data set, `organisms`, to exemplify the matrix method for `euler()`.
- Added a data set, `pain`, to exemplify the table method for `euler()`.
- `euler.table()` gains an argument, `factor_names`, for specifying
  whether the factor names should be included when generating dummy-coded
  variables in case the input is a data.frame with character or factor vectors
  or if the input is a table with more than two columns or rows.
- Parts of the _eulerr under the hood_ vignette has been branched off into
  a new vignette regarding visualization.

## Bug fixes

- Empty combinations can now be provided and will be plotted (generating
  completely blank plots).
- `euler.list()` now passes its ellipsis argument along properly. (#33,
  thanks, @banfai)
- Several spelling and grammar mistakes were corrected in vignettes and
  documentation.

# eulerr 4.1.0

## Minor changes

- `plot.euler()` now returns a `gTree` object. All of the plotting mechanisms
  are now also found in this function and `plot.eulergram()` and
  `print.eulergram()` basically just call `grid::grid.draw()` on the result
  of `plot.euler()`. This change means that functions such as
  `gridExtra::grid.arrange()` now work as one would intuit on the objects
  produced by `plot.euler()`.
- Fitting and plotting Euler diagrams with empty sets is now allowed (#23).
  Empty sets in the input will be returned as `NA` in the resulting
  `data.frame` of ellipses.
- The last-ditch optimizer has been switched back to `GenSA::GenSA()` from
  `RcppDE::DEoptim()`.

## Bug fixes

- The **grid** parameters available for _edges_ are now correctly specified in
  the manual for `plot.euler()`.
- `euler.data.frame()` now works as expected for tibbles (from the **tibble**
  package) when argument `by` is used.

# eulerr 4.0.0

## Major changes

- `plot.euler()` has been rewritten completely from scratch, now using
  a custom **grid**-based implementation rather than **lattice**. As a result,
  all `panel.*()` functions and `label()` have been deprecated as well
  as arguments `fill_alpha`, `auto.key`, `fontface`, `par.settings`,
  `default.prepanel`, `default.scales`, and `panel`. The
  method for plotting diagrams has also changed---rather than overlaying
  shapes on top of each other, the diagram is now split into separate polygons
  using the **polyclip** package. Instead of relying on semi-transparent fills,
  the colors of the fills are now blended in the CIELab color space (#16).
- The default color palette has been redesigned from scratch to suit the
  new plot method.
- A new function `eulerr_options()` have been provided in order to set
  default graphical parameters for the diagrams.

## Minor changes

- Arguments `counts` and `outer_strips` to `plot.euler()` are now defunct.
- `euler()` now always returns ellipse-based parameters
  with columns `h`, `k`, `a`, `b`, and `phi`, regardless of which shape is used.
  This item was previously named "coefficients", but it now called
  "ellipses" instead and a custom `coef.euler()` method has been added to
  make cure that `coef()` still works.
- Layouts are now partially normalized so that diagrams will look
  approximately the same even with different random seeds.

## Bug fixes

- Providing custom labels to `quantities` and `labels` arguments of
  `plot.euler()` now works correctly (#20).

# eulerr 3.1.0

## Major changes

- The last-ditch optimizer switched from `GenSA::GenSA()` to
  `RcppDE::DEoptim()`.
- The optimizer used in all the remaining cases, including all circular
  diagrams and initial layouts, was switched back to `stats::nlm()` again.
- In final optimization, we now use _stress_ instead of residual sums
  of squares as a target for our optimizer.

## Minor changes

- `label` is now a proper generic with an appropriate method (`label.euler()`).
- The **eulerr under the hood** vignette has received a substantial update.

## Bug fixes

- Fixed warnings resulting from the deprecated `counts` argument in one
  of the vignettes.
- Fixed memcheck errors in the final optimizer.
- Corrected erroneous labeling when `auto.key = TRUE` and labels were
  _not_ in alphabetic order. (#15)

# eulerr 3.0.1

## Bug fixes

- Added the missing %\\VignetteEngine{knitr::knitr} to both vignettes. It had
  mistakenly been left out, which had mangled the resulting vignettes.

# eulerr 3.0.0

## Major changes

- Ellipses are now supported by setting the new argument `shape = "ellipse"`
  in `euler()`. This functionality accompanies an overhaul of the
  innards of the function.
- Initial optimization function and gradient have been ported to C++.
- The initial optimizer has been switched from
  `stats::optim(..., method = "L-BFGS-B")` to `stats::nlminb()`.
- The final optimizer now falls back to `GenSA::GenSA()` when the fit from
  `nlminb()` isn't good enough, by default for 3 sets and ellipses, but
  this behavior can be controlled via a new argument `control`.
- A packing algorithm has been introduced to arrange disjoint clusters of
  ellipses/circles.
- The label placement algorithm has been rewritten to handle ellipses and
  been ported to C++. It now uses numerical optimization, which should
  provide slightly more accurate locations.
- The initial optimizer now uses an analytical Hessian in addition to
  gradient.

## Minor changes

- The initial optimizer now restarts up to 10 times and picks the best
  fit (unless it is perfect somewhere along the way).
- The default palette has been changed to a fixed palette, still adapted
  to color deficiency, but with some manual adjustments to, among other things,
  avoid unnecessary use of color.
- The names of the `diagError` and `regionError` metrics have been changed from
  `diag_error` and `region_error` to reflect the original names.
- The coordinates for the centers are now called _h_ and _k_ instead of
  _x_ and _y_, respectively.
- A new `label()` function has been added to extract locations for the overlaps
  for third party plotting (#10).
- The `counts` argument to `plot.euler()` and `panel.euler.labels()` have
  been deprecated in favor of the more appropriate `quantities`.
- Argument `fill_opacity` in `plot.euler()` that was deprecated in
  [v2.0.0](https://github.com/jolars/eulerr/releases/tag/v2.0.0) has been made
  defunct.

# eulerr 2.0.0

## Major changes

- `eulerr()` has been replaced with `euler()` (see update 1.1.0) and made
  defunct.
- There are two new methods for `euler`:
  - `euler.list()` produces diagrams from a list of sample spaces.
  - `euler.table()` produces diagrams from a `table` object, as long as there
    are no dimensions with values greater than 2.
- `plot.euler()` has been rewritten (again) from the ground up to better match
  other high-level functions from **lattice**. This change is intended to be
  as smooth as possible and should not make much of a difference to _most_ users.
- Arguments `polygon_args`, `mar`, and `text_args` to `plot.euler()` have been
  made defunct.

## Minor changes

- `plot.euler()` handles conflicting arguments better.
- c++ routines in `eulerr` now use registration.
- `euler()` now allows single sets (#9).
- Labels in `plot.euler()` now use a bold font face by default in order to
  distinguish them from the typeface used for counts.
- Argument `key` in `plot.euler()` has been deprecated and replaced with
  `auto.key`. Notice that using `key` does not throw a warning since the
  argument is used in `lattice::xyplot()` (which `plot.euler()` relies on).
- Argument `fill_opacity` is softly deprecated and has been replaced with
  `fill_alpha` for consistency with other lattice functions.

## Bug fixes

- `border` argument in `plot.euler()` works again (#7).

# eulerr 1.1.0

## Major changes

- `eulerr()` and its related methods been deprecated and are being replaced by
  `euler()`, which takes slightly different input. Notably, the default is
  now to provide input in the form of disjoint class combinations, rather
  than unions. This is partly to make the function a drop-in replacement for
  `venneuler::venneuler`.
- `plot.euler()` has been completely revamped, now interfacing `xyplot()` from
  lattice. As a result, arguments `polygon_args`, `mar`, and `text_args` have been
  deprecated.

## Minor changes

- Added a `counts` argument to `plot.eulerr`, which intersections and
  complements with counts from the original set specification (#6).
- Added a `key` argument to `plot.eulerr` that prints a legend next to the
  diagram.
- Switched to `atan2()` from RcppArmadillo.
- Added version requirement for RcppArmadillo.
- Dropped dependency on MASS for computing label placement, replacing it
  with a faster, geometric algorithm.
- Dropped the cost function argument `cost` and now forces the function to
  use sums of squares, which is more or less equivalent to the cost function
  from `venneuler`.
- Color palettes in `plot.euler()` now chooses colors adapted to color vision
  deficiency (deuteranopia). With increasingly large numbers of sets, this
  adaptation is relaxed to make sure that colors are kept visually distinct.
- `euler()` now uses `nlm()` instead of `optim(method = "Nelder-Mead")` for
  its final optimization.

## Bug fixes

- The previous algorithm incorrectly computed loss from unions of sets. It now
  computes loss from disjoint class combinations.
- Added missing row breaks in `print.eulerr`.

# eulerr 1.0.0

## New features

- Final optimization routines have been completely rewritten in C++ using Rcpp
  and RcppArmadillo.
- Switched to the cost function from EulerAPE for the default optimization
  target but added the possibility to choose cost function via a `cost` argument
  (currently `eulerAPE` or `venneuler`).
- Added the option to produce conditional eulerr plots via a `by` argument to
  `eulerr`. The result is a list of Euler diagrams that can be plotted
  in a grid arrangement via a new plot method.
- Improved label placement by using a two-dimensional kernel density estimation
  instead of means to calculate label centers.

## Bug fixes and minor improvements

- Cleaned up typos and grammar errors in the _Introduction to eulerr_ vignette.
- Added `mar` argument to `plot.eulerr` with a default that produces
  symmetric margins.
- Corrected the implementation of the `stress` statistic from venneuler.
- Switched to Vogel sampling to generate points to choose label positions from.
- Minor clean up and performance fixes all around.
- Added a `print.eulerr` method.
- Updated vignette to cover new features and changes.

# eulerr 0.1.0

- The first release.
