v0.3.3

RationalFunctionApproximation v0.3.3

Diff since v0.3.2

• Fix for derivatives of barycentric representation when there is a zero weight

v0.3.2

RationalFunctionApproximation v0.3.2

Diff since v0.3.1

• Stable formulas for derivatives of all order, for both continued fraction and barycentric representations
• Fix to get more accurate poles and residues in extended precision

Merged pull requests:

• Bump actions/checkout from 5 to 6 (#19) (@dependabot[bot])
• Bump actions/cache from 4 to 5 (#20) (@dependabot[bot])
• Increase numerical stability of poles for a barycentric model (#22) (@kbarros)

Closed issues:

• How to find simple pole expansion that maintains high acuracy? (#21)

v0.3.1

RationalFunctionApproximation v0.3.1

Diff since v0.3.0

• Added a filter to the "bad poles" check that ignores poles with very small residue.

v0.3.0

RationalFunctionApproximation v0.3.0

Diff since v0.2.7

Breaking changes

The Approximation class was made abstract and split into two concrete subtypes, ContinuumApproximation and DiscreteApproximation. The main user-facing breaking result is that calls to approximate with discrete data now return a single output, a DiscreteApproximation, rather than a naked interpolant and history tuple.

Other changes

• Aliases AAA = Barycentric and TCF = Thiele.
• More efficient use of memory in the discrete iterations for both AAA and TCF.

v0.2.7

RationalFunctionApproximation v0.2.7

Diff since v0.2.6

• speed improvement for using DiscretizedPath
• robustness improvements for Thiele
• AAA continuum uses both endpoints to start for an interval
• add isreal for Barycentric and Thiele

Merged pull requests:

• CompatHelper: add new compat entry for ForwardDiff in [weakdeps] at version 1, (keep existing compat) (#18) (@github-actions[bot])

v0.2.6

RationalFunctionApproximation v0.2.6

Diff since v0.2.5

• Significant speedup to Thiele weight computation and evaluation
• Improved residue speed and accuracy for Thiele
• Autodifferentiation not needed for Barycentric and Thiele; moved to extensions for Zygote and ForwardDiff
• Autodifferentiation fixed for partial fractions
• Improvements to and refactoring of unit tests
• Better stagnation and stopping convergence criteria
• Other minor enhancements and fixes

Merged pull requests:

• Bump actions/checkout from 4 to 5 (#16) (@dependabot[bot])

Closed issues:

• derivative support (#11)

v0.2.5

RationalFunctionApproximation v0.2.5

Diff since v0.2.4

• experimental support for derivatives of Thiele and Barycentric functions (not fully reliable yet)
• support for arithmetic operations and composition with Approximation objects
• many new tests with better code coverage
• bug fixes

Merged pull requests:

• correct aaa (#14) (@yuiyuiui)
• Slightly simplified plotting code in examples (#15) (@eprovst)

v0.2.4

RationalFunctionApproximation v0.2.4

Diff since v0.2.3

Tweaks to the stagnation and maximum iterations for better default performance.

v0.2.3

RationalFunctionApproximation v0.2.3

Diff since v0.2.2

• Big refactoring to simplify the iterations, especially for Thiele. While there are more memory allocations required in some cases, the timing differences are small to none.
• The stagnation criterion has been improved to be more reliable and intuitive.
• When premature stopping is detected, the algorithm now looks for the most accurate allowed iteration, rather than the last one.

v0.2.2

RationalFunctionApproximation v0.2.2

Diff since v0.2.1

• updated prescribed poles approximation to allow discrete domain
• backslash for projection onto an ArnoldiBasis
• improved documentation strings
• expanded test coverage