NEWS

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T4transport 0.1.9

• The rbaryGD() function allows arbitrary step-size selection for $\alpha \in (0,1]$ provided by a user. Default is $\alpha=1$.

T4transport 0.1.8 (2026-01-11)

• Changed hdist() to histdist() for modality-specific computation.
• imagebary() added for unregularized Wasserstein barycenter of images.
• imagedist() added for the Wasserstein distance between two images.
• imageinterp() added for Wasserstein interpolation between two images.
• imagemed() added for unregularized Wasserstein median of images.

T4transport 0.1.7 (2025-12-22)

• Removed dependence on CVXR package.

T4transport 0.1.6

• API references restructured.
• Added a number of functions for histograms, including distance, barycenter, interpolation, and median.
• Added img2measure() to extract a discrete measure from a gray-scale image matrix.
• New family of routines for Gromov-Wasserstein geometry, gwdist() and gwbary(), added.

T4transport 0.1.5 (2025-11-13)

• Replaced lpSolve package's EMD solver with Nicolas Bonneel's highly-optimized C library.
• Added functions for Procrustes-Wasserstein geometry: pwdist() and pwbary().

T4transport 0.1.4

• rbarygd() for a Riemannian gradient descent to compute the free-support barycenter is added.

T4transport 0.1.3 (2025-05-29)

• Changed the structure of the package.
• Applied the log-sum-exp trick for numerical stability to the entropic regularization solver.
• rbary23L() added for simple free-support Wasserstein barycenter computation.
• Two ad hoc median routines for images and histograms are removed.

T4transport 0.1.2 (2023-04-11)

• gaussmed1d() and gaussmedpd() now fully respects the product manifold perspective.
• gwdist() added for Sliced-Wasserstein distance computation.

T4transport 0.1.1 (2022-09-03)

• Support for special types of data. See the reference for more details.

T4transport 0.1.0 (2020-10-09)

• Added a NEWS.md file to track changes to the package.
• Initial release.