# Changelog

## v1.7.2 (Sep. 10, 2026)

### New features and support

*   Add {py:func}`~amplify.where` function.
*   Add {py:func}`~amplify.set_printoptions` to set the number of terms and significant digits shown.
*   Add the `alpha` parameter to {py:class}`~amplify.QAOA` and {py:class}`~amplify.RQAOA`, which makes the cost the Conditional Value-at-Risk (CVaR) of the measured energies.
*   Add {py:attr}`~amplify.FixstarsClient.objective_format` to {py:class}`~amplify.FixstarsClient`, {py:class}`~amplify.AmplifyAEClient`, and {py:class}`~amplify.ToshibaSQBM2Client`. The default {py:class}`~amplify.ObjectiveFormat.Auto` sends whichever of a dense matrix and a list of terms is smaller. Give {py:class}`~amplify.ObjectiveFormat.Dense` to keep the earlier behavior.
*   Add `__repr__` and `__str__` to {py:class}`~amplify.AcceptableDegrees`, {py:class}`~amplify.VariableGenerator`, {py:attr}`~amplify.Result.split`, and the key, value, and item views of {py:class}`~amplify.Values` and of the intermediate mapping. Each of them showed only its address before.
*   Support OQTOPUS Cloud with {py:class}`~amplify.OqtopusClient`.
*   Support Pyodide with a WebAssembly wheel that `micropip` installs and a browser runs. Only the formulation API and {py:class}`~amplify.AmplifyAEClient` work there, and each wheel fits one version of Pyodide.
*   Support the dense coupling mode of Amplify AE for a dense quadratic {py:class}`~amplify.Poly`, which needed a {py:class}`~amplify.Matrix` before.
*   Support file output for a model whose objective function is a {py:class}`~amplify.Matrix`.

### Changes of behavior

*   Change {py:attr}`~amplify.Model.objective` to always return a {py:class}`~amplify.Poly`. A model now copies the {py:class}`~amplify.Matrix` that you give it, and it accepts the addition or the subtraction of a {py:class}`~amplify.Poly`.
*   Change a model to drop the variables that a {py:class}`~amplify.Matrix` only declares. {py:attr}`~amplify.Model.variables` lists fewer variables, and the problem that the client sends becomes smaller.
*   Change {py:attr}`~amplify.QuadraticModel.input_matrix` and {py:attr}`~amplify.QuadraticModel.logical_matrix` to raise a {py:exc}`NotImplementedError`. Use {py:attr}`~amplify.QuadraticModel.input_poly` and {py:attr}`~amplify.QuadraticModel.logical_model_poly` instead.
*   Change {py:class}`~amplify.AmplifyAEClient` to warn when you give a weight to a constraint and solve with the default {py:class}`~amplify.AmplifyAEClient.Solver.Constraint` solver. Amplify AE sets the weight itself, so the tutorials and the examples no longer give one.
*   Change a bound that narrows a Binary or an Ising variable to raise a {py:exc}`ValueError`. Amplify dropped such a bound before, so it solved another model than the one you described. Use {py:func}`~amplify.equal_to` to fix a variable to one value.
*   Change a lower bound of positive infinity, or an upper bound of negative infinity, to raise a {py:exc}`ValueError`, because such a bound leaves no value. Amplify read it as "no bound" before, which widened the variable.
*   Change {py:func}`~amplify.load_lp` and {py:func}`~amplify.load_qplib` to give a constraint for a bound that narrows a Binary variable, such as `x <= 0`. Amplify dropped such a bound in silence before. Give the constraint enough weight, because a solver turns it into a penalty.
*   Change {py:func}`~amplify.load_qplib` to read an integer variable whose bounds are 0 and 1 as a {py:class}`~amplify.VariableType.Binary` variable, because QPLIB writes a binary variable in that form. Such a model held integer variables and no binary variable before.
*   Change {py:func}`~amplify.save_qplib` to warn when a variable bound or a constraint bound reaches an absolute value of 1e+20. QPLIB reads that value as infinity, so loading the file back drops the bound, or fails when the sign of the bound leaves nothing that satisfies it.
*   Change {py:func}`~amplify.save_lp` and {py:func}`~amplify.save_qplib` to raise a {py:exc}`ValueError` for a coefficient or a constraint bound that is NaN or infinity. Amplify wrote `nan` or `inf` into the file before, and neither format gives those a spelling.
*   Change {py:func}`~amplify.load_lp` and {py:func}`~amplify.load_qplib` to raise a {py:exc}`RuntimeError` for a value that is not a number, such as `nan`. {py:func}`~amplify.load_qplib` read such a value as zero in silence before, and {py:func}`~amplify.load_lp` gave a model that no solver accepts.
*   Change an integer parameter to raise a {py:exc}`TypeError` for a value that loses precision, such as `numpy.float64(3.0)`. It truncated such a value in silence before, and a NumPy integer, such as `numpy.int64(3)`, still works.
*   Change {py:func}`~amplify.set_num_threads` to limit the logical cores that Amplify uses, the parallel formulation included. Amplify caps a value that is larger than the number of the cores of the hardware.
*   Change {py:func}`~amplify.set_num_threads` and {py:func}`~amplify.set_seed` to take a named argument, `num_threads` and `seed`. A positional call still works.
*   Change `amplify.Dim0` through `amplify.Dim4` from classes to aliases of `tuple`, and add {py:class}`~amplify.N` for one axis. `PolyArray[Dim2]` still works, and only `isinstance` with one of these names stops.
*   Change the type stub to give the dimension of the result of an index, of a matrix product, and of an elementwise operation. A {py:class}`~amplify.PolyArray` that you build from a NumPy array or a list takes `PolyArray[Dim]`, which no `PolyArray[Dim2]` accepts.
*   Change the D-Wave solver names to agree with the D-Wave API. A solver name no longer holds the system revision, so Advantage_system4.1 is now Advantage_system4.
*   Remove `amplify.NECVA2Client` and `amplify.client.NECClient`. NEC Vector Annealing (VA) Service 2.0 ended on April 1, 2025, so the client reaches no machine.
*   Raise a {py:exc}`ValueError` when you solve a model whose objective function holds no variable.

### Performance

*   Improve performance of model formulation, including {py:func}`~amplify.einsum`, {py:func}`~amplify.one_hot`, and {py:meth}`~amplify.Model.to_unconstrained_poly`. The TSP formulation is now up to 30 times faster than v1.0. See [](benchmark.md).
*   Improve memory usage of model formulation. The TSP formulation now needs approximately one-fourth to one-fifth of the memory of v1.0 for a problem with more than 10,000 variables.
*   Improve performance of {py:meth}`~amplify.Model.to_intermediate_model` for a model with many integer or real variables, or with many higher-order terms.
*   Improve performance of {py:func}`~amplify.load_qplib`. A QPLIB file of 230 thousand terms now loads about 1.2 times faster.
*   Update {py:func}`~amplify.save_lp` and {py:func}`~amplify.save_qplib` to raise a {py:exc}`RuntimeError` for invalid variable names or constraint labels, and emit warnings for ignored constraint weights or duplicate variable names.

### Platform and dependencies

*   Update the D-Wave solver graphs for Advantage_system4, Advantage_system6, and Advantage2_system1.
*   Change supported macOS to Sonoma or later.
*   Update the required version of `typing_extensions` to `>= 4.16.0`, and of `amplify-quantum` to `>= 1.3.0`.

### Documentation

*   Publish the documentation in Markdown for AI agents. Every page has a Markdown copy next to it, and each language also carries `llms.txt` and `llms-full.txt`.
*   Add an English version of [](amplify_ae/summary.md), which introduces the latest Amplify AE.
*   Add a description of every operator of {py:class}`~amplify.Poly`, {py:class}`~amplify.PolyArray`, and {py:class}`~amplify.ConstraintList` to the API reference and to {py:func}`help`, and remove the signatures of a {py:class}`~amplify.PolyArray` operation that no call could reach.
*   Add a description of the settings that every client carries, such as {py:attr}`~amplify.FixstarsClient.url`, {py:attr}`~amplify.FixstarsClient.token`, and {py:attr}`~amplify.FixstarsClient.parameters`, and of each member of {py:class}`~amplify.PenaltyFormulation`.

### Fixes

*   Fix: {py:attr}`~amplify.Model.variables` and {py:meth}`~amplify.Model.get_variables` now list every variable of a {py:class}`~amplify.Matrix` objective whose first variable index is not zero.
*   Fix: {py:func}`~amplify.load_lp` and {py:func}`~amplify.save_lp` now support non-ASCII characters, such as Japanese, and a variable name of up to 255 characters, the indices included.
*   Fix: {py:func}`~amplify.load_lp` now reads a file that has no objective section, and gives a model whose objective is 0. It raised an error before.
*   Fix: {py:func}`~amplify.load_lp` now takes the type of a variable from the last variable type section that names it, as the LP format defines. A variable in both `Binary` and `Generals` became Binary before.
*   Fix: {py:func}`~amplify.load_lp` now reads a variable name that starts with the spelling of a number, such as `info` or `nano`. Such a file failed to load before.
*   Fix: {py:func}`~amplify.load_lp` now reads a bound that fixes a variable to one value, such as `x = 3`. Such a file failed to load before.
*   Fix: {py:func}`~amplify.load_lp` now reads a file that has no `End` line, which the LP format allows. Such a file failed to load before.
*   Fix: {py:func}`~amplify.save_lp` now raises a {py:exc}`RuntimeError` for a variable named `inf`, `infinity`, or `nan`. It wrote a file that no reader can load before.
*   Fix: {py:func}`~amplify.save_lp` now keeps the exact value of every coefficient and bound. It wrote 10 significant digits before, so `0.1234567890123456` came back as `0.123456789`.
*   Fix: {py:func}`~amplify.save_lp` now writes `-inf` for a variable that has no lower bound. The LP default of a lower bound is 0, so `x <= 3` alone gave the file another variable than the one you saved.
*   Fix: {py:func}`~amplify.save_lp` now writes the bound of a Binary variable as `0 <= q <= 1`. It wrote `q free` before, so the file gave a variable with no bound instead of a Binary one.
*   Fix: {py:func}`~amplify.save_lp` now writes a constraint that holds a constant with the right sign. `x + 5 <= 10` became `x <= 15` in the file, which is another constraint than the one you gave.
*   Fix: {py:func}`~amplify.save_lp` now writes every line within the 999 characters that the LP format allows, and it never breaks a bound over two lines. A file that held a long name failed to load.
*   Fix: {py:func}`~amplify.load_qplib` now drops a constraint bound that reaches the infinity value of the file, as the QPLIB format defines. Such a bound became a real constraint before. A bound whose sign leaves nothing that satisfies the constraint now raises.
*   Fix: {py:func}`~amplify.save_qplib` now keeps the exact value of every coefficient and bound. It wrote 6 significant digits before, so `0.1234567890123456` came back as `0.123457`.
*   Fix: {py:func}`~amplify.save_qplib` now writes a two-sided constraint that holds a constant with the right value on each side. `1 <= x + 5 <= 10` became `1 <= x <= 5` in the file, which is another constraint than the one you gave.
*   Fix: {py:func}`~amplify.save_qplib` now writes the two indices of a quadratic term in the lower triangle, as the QPLIB format defines. Another reader could not load the file before.
*   Fix: {py:func}`~amplify.save_qplib` now accepts a name that holds `!`, `%`, or `#` after its first character. It raised a {py:exc}`RuntimeError` for every such name before.
*   Fix: A model with an integer variable whose range exceeds 2147483647 now converts to the correct binary encoding. The solution of such a model did not solve the model that you gave before. A range that no encoding can build now raises an {py:exc}`OverflowError`.
*   Fix: {py:meth}`~amplify.Model.to_intermediate_model` now gives a solution that is optimal for the input model when the quadratization method is `IshikawaKZFD` and the objective function holds Ising variables of degree three or higher.
*   Fix: {py:meth}`~amplify.Model.to_intermediate_model` now raises a {py:exc}`ValueError` when the objective function and the constraints need different variable types. It returned a model of the forbidden variable type before.
*   Fix: An inequality constraint now gives a penalty function when Amplify cannot estimate the range of its left side, such as a left side that holds an unbounded variable. The penalty held NaN coefficients before, or it was 0, which removed the constraint from the model.
*   Fix: A constraint whose left side holds a squared term, such as `a * a <= 3` with `a` in `[-5, 5]`, now stays in the model. Amplify squared the two ends of the range only, so the constraint looked infeasible and its penalty became 0, or negative for an equality.
*   Fix: `&=`, `|=`, and `^=` now update a {py:class}`~amplify.PolyArray` in place. The name became `None` before when the right side was a {py:class}`~amplify.PolyArray`, and it took a copy otherwise.
*   Fix: {py:meth}`~amplify.PolyArray.roll` now returns a copy of an array that holds no element. It ended the process before.
*   Fix: The display of a {py:class}`~amplify.PolyArray` no longer puts a space at the end of a wrapped line.
*   Fix: `amplify` no longer gives the names that its own implementation imports, such as `amplify.sys` and `amplify.Never`. `from amplify import *` gave them away, and none of them was ever documented.
*   Fix: The type stub of {py:func}`~amplify.sum` and {py:meth}`~amplify.PolyArray.sum` now accepts `axis` for a zero-dimensional {py:class}`~amplify.PolyArray`. The call always worked, and only the stub rejected it.
*   Fix: The type stub of {py:func}`~amplify.clamp` now names the second parameter `bounds` when you give `axis` for a {py:class}`~amplify.PolyArray`. A call with that keyword failed the type check although it always worked.
*   Fix: The type stub of the `type` parameter of {py:class}`~amplify.HitachiClient` no longer accepts `None`. The parameter never took `None`, and such an assignment raised a {py:exc}`TypeError`.
*   Fix: {py:func}`repr` of a {py:class}`~amplify.Result` that holds no solution now names the class, as it does for a result that holds one. It gave a text that began with `{` and ended with an unmatched `)` before.

## v1.6.0 (May. 21, 2026)

*   Support quantum computers via the Amplify Quantum extension.
*   Support Ubuntu 26.04.
*   Support D-Wave Advantage2_system1.
*   Fix: Correct response data not being written to file with {py:attr}`~amplify.AmplifyAEClient.write_response_data` enabled in specific cases.

```{dropdown} v1.6.1 (Jun. 09, 2026)

*   Add `dwave`, `quantum`, and `full` installation options, replacing the `extra` option with `full`.
*   Fix: {py:func}`~amplify.embed` now works without raising a {py:exc}`ValueError` in all environments.

```

```{dropdown} v1.6.2 (Jul. 10, 2026)

*   Deprecate `amplify.NECVA2Client`. NEC Vector Annealing (VA) Service 2.0 ended on April 1, 2025, so the client reaches no machine.
*   Improve performance of {py:meth}`~amplify.Model.to_unconstrained_poly`.
*   Fix: Work around a potential dependency resolution error when installing Amplify Quantum.
*   Fix: {py:func}`~amplify.parallel_solve` now works correctly with multiple client arguments.
*   Fix: {py:meth}`~amplify.PolyArray.__getitem__` now works correctly when a slice results in zero length.

```

```{dropdown} v1.6.3 (Aug. 20, 2026)

*   Support Amplify Quantum v1.3.
*   Improve performance of {py:meth}`~amplify.Model.get_variables`.
*   General security hardening and robustness improvements.
*   Fix: {py:meth}`~amplify.Model.to_unconstrained_poly` now works correctly with inequality constraints.

```

## v1.5.0 (Apr. 05, 2026)

*   Overhaul the docstrings.
*   Support `dense_objective` endpoint of Amplify AE v1.1.
*   Support Gurobi Optimizer 12.0.3 on {py:class}`~amplify.GurobiClient`.
*   Change default degree reduction algorithm to {py:class}`~amplify.QuadratizationMethod.Substitute` from {py:class}`~amplify.QuadratizationMethod.IshikawaKZFD`.

## v1.4.0 (Sep. 19, 2025)

*   Support Amplify Annealing Engine v1.0 on {py:class}`~amplify.AmplifyAEClient`.
*   Support D-Wave Advantage2_system1.6.
*   Deprecate D-Wave Advantage2_prototype2.6.
*   Rename `AmplifyClient` to {py:class}`~amplify.BaseClient`.
*   Support [D-Wave solver identification updates](https://docs.dwavequantum.com/projects/leap_sapi/en/latest/release_notes.html#solver-identification-update-deprecated-sapi-field) and update the dependent dwave-system package to v1.33.0.
*   Update type hints for {py:attr}`~amplify.PolyArray` and {py:func}`~amplify.PolyArray.sum`.
*   Fix: Substitute method for high-order polynomials now correctly reduces the degree to 2.
*   Fix: {py:func}`~amplify.einsum` now correctly handles integer NumPy arrays.
*   Fix: {py:class}`~amplify.FujitsuDA4Client` now correctly handles inequality constraints without constants.

```{dropdown} v1.4.1 (Oct 16, 2025)

*   Support Python 3.14, and Python 3.9 is no longer supported.
*   Fix: Resolved error of {py:attr}`~amplify.PolyArray.transpose` operation on an unassigned {py:class}`~amplify.PolyArray` class instance.

```

```{dropdown} v1.4.2 (Feb. 14, 2026)

*   Support Gurobi Optimizer 12.0.3 on {py:class}`~amplify.GurobiClient`.
*   Support D-Wave Advantage2_system1.11.
*   Fix: Update type hints for {py:func}`~amplify.sum`.

```

## v1.3.0 (Nov. 01, 2024)

*   Improve support for type annotations.
*   Improve accuracy of [upper and lower bounds estimates](#penalty-function-auto-generation) in constraint construction.
*   Change advanced parameters of {py:func}`~amplify.solve`, {py:func}`~amplify.parallel_solve`, {py:func}`~amplify.equal_to`, {py:func}`~amplify.less_equal`, {py:func}`~amplify.greater_equal` and {py:func}`~amplify.clamp` functions to keyword-only arguments for usability.
*   Support [Hitachi CMOS annealing](https://annealing-cloud.com/) on {py:class}`~amplify.HitachiClient`.
*   Support D-Wave Advantage2_prototype2.5.
*   Support conversion from {py:class}`~amplify.Variable` to {py:class}`~amplify.Poly`.
*   Support input/output of models with [LP](https://docs.gurobi.com/projects/optimizer/en/current/reference/fileformats/modelformats.html#lp-format) and [QPLIB](https://doi.org/10.1007/s12532-018-0147-4) format files.
*   {py:class}`~amplify.Variable` can be used as a mapping key for {py:func}`~amplify.Poly.substitute`, {py:func}`~amplify.PolyArray.substitute` and {py:func}`~amplify.Constraint.is_satisfied`.
*   Support conversion from real variables to binary variables.
*   Add `compress_qpu_problem_data` attribute to {py:class}`~amplify.DWaveSamplerClient`, {py:class}`~amplify.LeapHybridSamplerClient` and {py:class}`~amplify.LeapHybridCQMSamplerClient`.
*   Add support for Python 3.13, and Python 3.8 is no longer supported.

```{dropdown} v1.3.1 (Nov. 18, 2024)

*   Fix: Prevent segmentation fault when accessing variables through {py:meth}`~amplify.Model.get_variables` or {py:attr}`~amplify.Model.variables` property on empty models.
*   Fix: Correct `total_elapsed_time` in {py:class}`~amplify.FujitsuDA4Client.SolverTiming` to reference the proper timing value.
*   Fix: Update type hints for {py:func}`~amplify.domain_wall` and {py:attr}`~amplify.VariableGenerator.array`.

```

## v1.2.0 (July 23, 2024)

*   Support TOSHIBA SQBM+ v2.0.3 on {py:class}`~amplify.ToshibaSQBM2Client`.

```{dropdown} v1.2.1 (Aug. 06, 2024)

* Change supported macOS to Monterey or later.

```

## v1.1.0 (May 13, 2024)

*   Support NEC Vector Annealing Service 2.0 on `amplify.NECVA2Client`.
*   Improve the efficiency of the {py:class}`~amplify.QuadratizationMethod.Substitute` quadratization method and significantly reduce the number of auxiliary variables.
*   Add support for Linux ARM64.

```{dropdown} v1.1.1 (May 28, 2024)

* Fix type hints for `Result` class.

```

## v1.0.0 (Jan. 27, 2024)

*   Release version 1.0.

```{dropdown} v1.0.2 (Feb. 20, 2024)

* Add documents in English.
* Fix redundant deprecation warnings.
* Add `client.ocean` namespace for legacy compatibility.

```

```{dropdown} v1.0.3 (Mar. 01, 2024)

* Support D-Wave Advantage_system6.4.
* Support D-Wave Advantage2_prototype2.2.

```

```{dropdown} v1.0.4 (Mar. 15, 2024)

* Fix a problem where SQBM request data is not sent correctly on Windows.

```

```{dropdown} v1.0.5 (Mar. 19, 2024)

* Support D-Wave Advantage2_prototype2.3.

```