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# SciPy 1.4.0 Release Notes

SciPy 1.4.0 is the culmination of 6 months of hard work. It contains many new features, numerous bug-fixes, improved test coverage and better documentation. There have been a number of deprecations and API changes in this release, which are documented below. All users are encouraged to upgrade to this release, as there are a large number of bug-fixes and optimizations. Before upgrading, we recommend that users check that their own code does not use deprecated SciPy functionality (to do so, run your code with `python -Wd` and check for `DeprecationWarning` s). Our development attention will now shift to bug-fix releases on the 1.4.x branch, and on adding new features on the master branch.

This release requires Python 3.5+ and NumPy >=1.13.3 (for Python 3.5, 3.6), >=1.14.5 (for Python 3.7), >= 1.17.3 (for Python 3.8)

For running on PyPy, PyPy3 6.0+ and NumPy 1.15.0 are required.

## Highlights of this release

- a new submodule, `scipy.fft`, now supersedes `scipy.fftpack`; this means support for `long double` transforms, faster multi-dimensional transforms, improved algorithm time complexity, release of the global intepreter lock, and control over threading behavior

- support for `pydata/sparse` arrays in `scipy.sparse.linalg`

- substantial improvement to the documentation and functionality of several `scipy.special` functions, and some new additions

- the generalized inverse Gaussian distribution has been added to `scipy.stats`

- an implementation of the Edmonds-Karp algorithm in `scipy.sparse.csgraph.maximum_flow`

- `scipy.spatial.SphericalVoronoi` now supports n-dimensional input,

    has linear memory complexity, improved performance, and supports single-hemisphere generators

### New features

## Infrastructure

Documentation can now be built with `runtests.py --doc`

A `Dockerfile` is now available in the `scipy/scipy-dev` repository to facilitate getting started with SciPy development.

## `scipy.constants` improvements

`scipy.constants` has been updated with the CODATA 2018 constants.

## `scipy.fft` added

`scipy.fft` is a new submodule that supersedes the `scipy.fftpack` submodule. For the most part, this is a drop-in replacement for `numpy.fft` and `scipy.fftpack` alike. With some important differences, `scipy.fft`: - uses NumPy’s conventions for real transforms (`rfft`). This means the return value is a complex array, half the size of the full `fft` output. This is different from the output of `fftpack` which returned a real array representing complex components packed together. - the inverse real to real transforms (`idct` and `idst`) are normalized for `norm=None` in thesame way as `ifft`. This means the identity `idct(dct(x)) == x` is now `True` for all norm modes. - does not include the convolutions or pseudo-differential operators from `fftpack`.

This submodule is based on the `pypocketfft` library, developed by the author of `pocketfft` which was recently adopted by NumPy as well. `pypocketfft` offers a number of advantages over fortran `FFTPACK`: - support for long double (`np.longfloat`) precision transforms. - faster multi-dimensional transforms using vectorisation - Bluestein’s algorithm removes the worst-case `O(n^2)` complexity of `FFTPACK` - the global interpreter lock (`GIL`) is released during transforms - optional multithreading of multi-dimensional transforms via the `workers` argument

Note that `scipy.fftpack` has not been deprecated and will continue to be maintained but is now considered legacy. New code is recommended to use `scipy.fft` instead, where possible.

## `scipy.fftpack` improvements

`scipy.fftpack` now uses pypocketfft to perform its FFTs, offering the same speed and accuracy benefits listed for scipy.fft above but without the improved API.

## `scipy.integrate` improvements

The function `scipy.integrate.solve_ivp` now has an `args` argument. This allows the user-defined functions passed to the function to have additional parameters without having to create wrapper functions or lambda expressions for them.

`scipy.integrate.solve_ivp` can now return a `y_events` attribute representing the solution of the ODE at event times

New `OdeSolver` is implemented — `DOP853`. This is a high-order explicit Runge-Kutta method originally implemented in Fortran. Now we provide a pure Python implementation usable through `solve_ivp` with all its features.

`scipy.integrate.quad` provides better user feedback when break points are specified with a weighted integrand.

`scipy.integrate.quad_vec` is now available for general purpose integration of vector-valued functions

## `scipy.interpolate` improvements

`scipy.interpolate.pade` now handles complex input data gracefully

`scipy.interpolate.Rbf` can now interpolate multi-dimensional functions

## `scipy.io` improvements

`scipy.io.wavfile.read` can now read data from a WAV file that has a malformed header, similar to other modern WAV file parsers

`scipy.io.FortranFile` now has an expanded set of available `Exception` classes for handling poorly-formatted files

## `scipy.linalg` improvements

The function `scipy.linalg.subspace_angles(A, B)` now gives correct results for complex-valued matrices. Before this, the function only returned correct values for real-valued matrices.

New boolean keyword argument `check_finite` for `scipy.linalg.norm`; whether to check that the input matrix contains only finite numbers. Disabling may give a performance gain, but may result in problems (crashes, non-termination) if the inputs do contain infinities or NaNs.

`scipy.linalg.solve_triangular` has improved performance for a C-ordered triangular matrix

`LAPACK` wrappers have been added for `?geequ`, `?geequb`, `?syequb`, and `?heequb`

Some performance improvements may be observed due to an internal optimization in operations involving LAPACK routines via `_compute_lwork`. This is particularly true for operations on small arrays.

Block `QR` wrappers are now available in `scipy.linalg.lapack`

## `scipy.ndimage` improvements

## `scipy.optimize` improvements

It is now possible to use linear and non-linear constraints with `scipy.optimize.differential_evolution`.

`scipy.optimize.linear_sum_assignment` has been re-written in C++ to improve performance, and now allows input costs to be infinite.

A `ScalarFunction.fun_and_grad` method was added for convenient simultaneous retrieval of a function and gradient evaluation

`scipy.optimize.minimize` `BFGS` method has improved performance by avoiding duplicate evaluations in some cases

Better user feedback is provided when an objective function returns an array instead of a scalar.

## `scipy.signal` improvements

Added a new function to calculate convolution using the overlap-add method, named `scipy.signal.oaconvolve`. Like `scipy.signal.fftconvolve`, this function supports specifying dimensions along which to do the convolution.

`scipy.signal.cwt` now supports complex wavelets.

The implementation of `choose_conv_method` has been updated to reflect the new FFT implementation. In addition, the performance has been significantly improved (with rather drastic improvements in edge cases).

The function `upfirdn` now has a `mode` keyword argument that can be used to select the signal extension mode used at the signal boundaries. These modes are also available for use in `resample_poly` via a newly added `padtype` argument.

`scipy.signal.sosfilt` now benefits from Cython code for improved performance

`scipy.signal.resample` should be more efficient by leveraging `rfft` when possible

## `scipy.sparse` improvements

It is now possible to use the LOBPCG method in `scipy.sparse.linalg.svds`.

`scipy.sparse.linalg.LinearOperator` now supports the operation `rmatmat` for adjoint matrix-matrix multiplication, in addition to `rmatvec`.

Multiple stability updates enable float32 support in the LOBPCG eigenvalue solver for symmetric and Hermitian eigenvalues problems in `scipy.sparse.linalg.lobpcg`.

A solver for the maximum flow problem has been added as `scipy.sparse.csgraph.maximum_flow`.

`scipy.sparse.csgraph.maximum_bipartite_matching` now allows non-square inputs, no longer requires a perfect matching to exist, and has improved performance.

`scipy.sparse.lil_matrix` conversions now perform better in some scenarios

Basic support is available for `pydata/sparse` arrays in `scipy.sparse.linalg`

`scipy.sparse.linalg.spsolve_triangular` now supports the `unit_diagonal` argument to improve call signature similarity with its dense counterpart, `scipy.linalg.solve_triangular`

`assertAlmostEqual` may now be used with sparse matrices, which have added support for `__round__`

## `scipy.spatial` improvements

The bundled Qhull library was upgraded to version 2019.1, fixing several issues. Scipy-specific patches are no longer applied to it.

`scipy.spatial.SphericalVoronoi` now has linear memory complexity, improved performance, and supports single-hemisphere generators. Support has also been added for handling generators that lie on a great circle arc (geodesic input) and for generators in n-dimensions.

`scipy.spatial.transform.Rotation` now includes functions for calculation of a mean rotation, generation of the 3D rotation groups, and reduction of rotations with rotational symmetries.

`scipy.spatial.transform.Slerp` is now callable with a scalar argument

`scipy.spatial.voronoi_plot_2d` now supports furthest site Voronoi diagrams

`scipy.spatial.Delaunay` and `scipy.spatial.Voronoi` now have attributes for tracking whether they are furthest site diagrams

## `scipy.special` improvements

The Voigt profile has been added as `scipy.special.voigt_profile`.

A real dispatch has been added for the Wright Omega function (`scipy.special.wrightomega`).

The analytic continuation of the Riemann zeta function has been added. (The Riemann zeta function is the one-argument variant of `scipy.special.zeta`.)

The complete elliptic integral of the first kind (`scipy.special.ellipk`) is now available in `scipy.special.cython_special`.

The accuracy of `scipy.special.hyp1f1` for real arguments has been improved.

The documentation of many functions has been improved.

## `scipy.stats` improvements

`scipy.stats.multiscale_graphcorr` added as an independence test that operates on high dimensional and nonlinear data sets. It has higher statistical power than other `scipy.stats` tests while being the only one that operates on multivariate data.

The generalized inverse Gaussian distribution (`scipy.stats.geninvgauss`) has been added.

It is now possible to efficiently reuse `scipy.stats.binned_statistic_dd` with new values by providing the result of a previous call to the function.

`scipy.stats.hmean` now handles input with zeros more gracefully.

The beta-binomial distribution is now available in `scipy.stats.betabinom`.

`scipy.stats.zscore`, `scipy.stats.circmean`, `scipy.stats.circstd`, and `scipy.stats.circvar` now support the `nan_policy` argument for enhanced handling of `NaN` values

`scipy.stats.entropy` now accepts an `axis` argument

`scipy.stats.gaussian_kde.resample` now accepts a `seed` argument to empower reproducibility

`scipy.stats.kendalltau` performance has improved, especially for large inputs, due to improved cache usage

`scipy.stats.truncnorm` distribution has been rewritten to support much wider tails

### Deprecated features

## `scipy` deprecations

Support for NumPy functions exposed via the root SciPy namespace is deprecated and will be removed in 2.0.0. For example, if you use `scipy.rand` or `scipy.diag`, you should change your code to directly use `numpy.random.default_rng` or `numpy.diag`, respectively. They remain available in the currently continuing Scipy 1.x release series.

The exception to this rule is using `scipy.fft` as a function – `scipy.fft` is now meant to be used only as a module, so the ability to call `scipy.fft(...)` will be removed in SciPy 1.5.0.

In scipy.spatial.Rotation methods `from_dcm`, `as_dcm` were renamed to `from_matrix`, `as_matrix` respectively. The old names will be removed in SciPy 1.6.0.

Method `Rotation.match_vectors` was deprecated in favor of `Rotation.align_vectors`, which provides a more logical and general API to the same functionality. The old method will be removed in SciPy 1.6.0.

### Backwards incompatible changes

## `scipy.special` changes

The deprecated functions `hyp2f0`, `hyp1f2`, and `hyp3f0` have been removed.

The deprecated function `bessel_diff_formula` has been removed.

The function `i0` is no longer registered with `numpy.dual`, so that `numpy.dual.i0` will unconditionally refer to the NumPy version regardless of whether `scipy.special` is imported.

The function `expn` has been changed to return `nan` outside of its domain of definition (`x, n < 0`) instead of `inf`.

## `scipy.sparse` changes

Sparse matrix reshape now raises an error if shape is not two-dimensional, rather than guessing what was meant. The behavior is now the same as before SciPy 1.1.0.

`CSR` and `CSC` sparse matrix classes should now return empty matrices of the same type when indexed out of bounds. Previously, for some versions of SciPy, this would raise an `IndexError`. The change is largely motivated by greater consistency with `ndarray` and `numpy.matrix` semantics.

## `scipy.signal` changes

`scipy.signal.resample` behavior for length-1 signal inputs has been fixed to output a constant (DC) value rather than an impulse, consistent with the assumption of signal periodicity in the FFT method.

`scipy.signal.cwt` now performs complex conjugation and time-reversal of wavelet data, which is a backwards-incompatible bugfix for time-asymmetric wavelets.

## `scipy.stats` changes

`scipy.stats.loguniform` added with better documentation as (an alias for `scipy.stats.reciprocal`). `loguniform` generates random variables that are equally likely in the log space; e.g., `1`, `10` and `100` are all equally likely if `loguniform(10 ** 0, 10 ** 2).rvs()` is used.

### Other changes

The `LSODA` method of `scipy.integrate.solve_ivp` now correctly detects stiff problems.

`scipy.spatial.cKDTree` now accepts and correctly handles empty input data

`scipy.stats.binned_statistic_dd` now calculates the standard deviation statistic in a numerically stable way.

`scipy.stats.binned_statistic_dd` now throws an error if the input data contains either `np.nan` or `np.inf`. Similarly, in `scipy.stats` now all continuous distributions’ `.fit()` methods throw an error if the input data contain any instance of either `np.nan` or `np.inf`.

### Authors

- @endolith

- @wenhui-prudencemed +

- Abhinav +

- Anne Archibald

- ashwinpathak20nov1996 +

- Danilo Augusto +

- Nelson Auner +

- aypiggott +

- Christoph Baumgarten

- Peter Bell

- Sebastian Berg

- Arman Bilge +

- Benedikt Boecking +

- Christoph Boeddeker +

- Daniel Bunting

- Evgeni Burovski

- Angeline Burrell +

- Angeline G. Burrell +

- CJ Carey

- Carlos Ramos Carreño +

- Mak Sze Chun +

- Malayaja Chutani +

- Christian Clauss +

- Jonathan Conroy +

- Stephen P Cook +

- Dylan Cutler +

- Anirudh Dagar +

- Aidan Dang +

- dankleeman +

- Brandon David +

- Tyler Dawson +

- Dieter Werthmüller

- Joe Driscoll +

- Jakub Dyczek +

- Dávid Bodnár

- Fletcher Easton +

- Stefan Endres

- etienne +

- Johann Faouzi

- Yu Feng

- Isuru Fernando +

- Matthew H Flamm

- Martin Gauch +

- Gabriel Gerlero +

- Ralf Gommers

- Chris Gorgolewski +

- Domen Gorjup +

- Edouard Goudenhoofdt +

- Jan Gwinner +

- Maja Gwozdz +

- Matt Haberland

- hadshirt +

- Pierre Haessig +

- David Hagen

- Charles Harris

- Gina Helfrich +

- Alex Henrie +

- Francisco J. Hernandez Heras +

- Andreas Hilboll

- Lindsey Hiltner

- Thomas Hisch

- Min ho Kim +

- Gert-Ludwig Ingold

- jakobjakobson13 +

- Todd Jennings

- He Jia

- Muhammad Firmansyah Kasim +

- Andrew Knyazev +

- Holger Kohr +

- Mateusz Konieczny +

- Krzysztof Pióro +

- Philipp Lang +

- Peter Mahler Larsen +

- Eric Larson

- Antony Lee

- Gregory R. Lee

- Chelsea Liu +

- Jesse Livezey

- Peter Lysakovski +

- Jason Manley +

- Michael Marien +

- Nikolay Mayorov

- 7. 4. McBain +

- Sam McCormack +

- Melissa Weber Mendonça +

- Kevin Michel +

- mikeWShef +

- Sturla Molden

- Eric Moore

- Peyton Murray +

- Andrew Nelson

- Clement Ng +

- Juan Nunez-Iglesias

- Renee Otten +

- Kellie Ottoboni +

- Ayappan P

- Sambit Panda +

- Tapasweni Pathak +

- Oleksandr Pavlyk

- Fabian Pedregosa

- Petar Mlinarić

- Matti Picus

- Marcel Plch +

- Christoph Pohl +

- Ilhan Polat

- Siddhesh Poyarekar +

- Ioannis Prapas +

- James Alan Preiss +

- Yisheng Qiu +

- Eric Quintero

- Bharat Raghunathan +

- Tyler Reddy

- Joscha Reimer

- Antonio Horta Ribeiro

- Lucas Roberts

- rtshort +

- Josua Sassen

- Kevin Sheppard

- Scott Sievert

- Leo Singer

- Kai Striega

- Søren Fuglede Jørgensen

- tborisow +

- Étienne Tremblay +

- tuxcell +

- Miguel de Val-Borro

- Andrew Valentine +

- Hugo van Kemenade

- Paul van Mulbregt

- Sebastiano Vigna

- Pauli Virtanen

- Dany Vohl +

- Ben Walsh +

- Huize Wang +

- Warren Weckesser

- Anreas Weh +

- Joseph Weston +

- Adrian Wijaya +

- Timothy Willard +

- Josh Wilson

- Kentaro Yamamoto +

- Dave Zbarsky +

A total of 142 people contributed to this release. People with a “+” by their names contributed a patch for the first time. This list of names is automatically generated, and may not be fully complete.

## Issues closed for 1.4.0

- #1255: maxiter broken for Scipy.sparse.linalg gmres, in addition to…

- #1301: consolidate multipack.h from interpolate and integrate packages…

- #1739: Single precision FFT insufficiently accurate. (Trac #1212)

- #1795: stats test_distributions.py: replace old fuzz tests (Trac #1269)

- #2233: fftpack segfault with big arrays (Trac #1714)

- #2434: rmatmat and the sophistication of linear operator objects

- #2477: stats.truncnorm.rvs() does not give symmetric results for negative…

- #2629: FFTpack is unacceptably slow on non power of 2

- #2883: UnboundLocalError in scipy.interpolate.splrep

- #2956: Feature Request: axis argument for stats.entropy function

- #3528: Segfault on test_djbfft (possibly MKL-related?)

- #3793: cwt should also return complex array

- #4464: TST: residue/residuez/invres/invresz don’t have any tests

- #4561: BUG: tf filter trailing and leading zeros in residuez

- #4669: Rewrite sosfilt to make a single loop over the input?

- #5040: BUG: Empty data handling of (c)KDTrees

- #5112: boxcox transform edge cases could use more care

- #5441: scipy.stats.ncx2 fails for nc=0

- #5502: args keyword not handled in optimize.curve_fit

- #6484: Qhull segmentation fault

- #6900: linear_sum_assignment with infinite weights

- #6966: Hypergeometric Functions documentation is lacking

- #6999: possible false positive corruption check in compressed loadmat()

- #7018: ydata that needs broadcasting renders curve_fit unable to compute…

- #7140: trouble with documentation for windows

- #7327: interpolate.ndgriddata.griddata causes Python to crash rather…

- #7396: MatrixLinearOperator implements _adjoint(), but not _transpose()

- #7400: BUG(?): special: factorial and factorial2 return a 0-dimensional…

- #7434: Testing of scipy.stats continuous distributions misses 25 distributions

- #7491: Several scipy.stats distributions (fisk, burr, burr12, f) return…

- #7759: Overflow in stats.kruskal for large samples

- #7906: Wrong result from scipy.interpolate.UnivariateSpline.integral…

- #8165: ENH: match functionality of R for hmean

- #8417: optimimze.minimize(method=’L-BFGS-B’, options={‘disp’: True})…

- #8535: Strictly increasing requirement in UnivariateSpline

- #8815: [BUG] GMRES: number of iteration is only increased if callback…

- #9207: scipy.linalg.solve_triangular speed after scipy.linalg.lu_factor

- #9275: new feature: adding LOBPCG solver in svds in addition to ARPACK

- #9403: range of truncnorm.logpdf could be extended

- #9429: gaussian_kde not working with numpy matrix

- #9515: ndimage implementation relies on undefined behavior

- #9643: arpack returns singular values in ascending order

- #9669: DOC: matthew-brett/build-openblas has been retired

- #9852: scipy.spatial.ConvexHull exit with code 134, free(): invalid…

- #9902: scipy.stats.truncnorm second moment may be wrong

- #9943: Custom sampling methods in shgo do not work

- #9947: DOC: Incorrect documentation for `nan_policy=’propagate` in…

- #9994: BUG: sparse: reshape method allows a shape containing an arbitrary…

- #10036: Official Nelder mead tutorial uses xtol instead of xatol, which…

- #10078: possible to get a better error message when objective function…

- #10092: overflow in truncnorm.rvs

- #10121: A little spelling mistake

- #10126: inaccurate std implementation in binned_statistic

- #10161: Error in documentation scipy.special.modstruve

- #10195: Derivative of spline with ‘const’ extrapolation is also extrapolted…

- #10206: sparse matrices indexing with scipy 1.3

- #10236: Non-descriptive error on type mismatch for functions of scipy.optimize…

- #10258: LOBPCG convergence failure if guess provided

- #10262: distance matrix lacks dtype checks / warnings

- #10271: BUG: optimize failure on wheels

- #10277: scipy.special.zeta(0) = NAN

- #10292: DOC/REL: Some sections of the release notes are not nested correctly.

- #10300: scipy.stats.rv_continuous.fit throws empty RuntimeError when…

- #10319: events in scipy.integrate.solve_ivp: How do I setup an events…

- #10323: Adding more low-level LAPACK wrappers

- #10360: firwin2 inadvertently modifies input and may result in undefined…

- #10388: BLD: TestHerd::test_hetrd core dumps with Python-dbg

- #10395: Remove warning about output shape of zoom

- #10403: DOC: scipy.signal.resample ignores t parameter

- #10421: Yeo-Johnson power transformation fails with integer input data

- #10422: BUG: scipy.fft does not support multiprocessing

- #10427: ENH: convolve numbers should be updated

- #10444: BUG: scipy.spatial.transform.Rotation.match_vectors returns improper…

- #10488: ENH: DCTs/DSTs for scipy.fft

- #10501: BUG: scipy.spatial.HalfspaceIntersection works incorrectly

- #10514: BUG: cKDTree GIL handling is incorrect

- #10535: TST: master branch CI failures

- #10588: scipy.fft and numpy.fft inconsistency when axes=None and shape…

- #10628: Scipy python>3.6 Windows wheels don’t ship msvcp*.dll

- #10733: DOC/BUG: min_only result does not match documentation

- #10774: min_only=true djisktra infinite loop with duplicate indices

- #10775: UnboundLocalError in Radau when given a NaN

- #10835: io.wavfile.read unnecessarily raises an error for a bad wav header

- #10838: Error in documentation for scipy.linalg.lu_factor

- #10875: DOC: Graphical guides (using TikZ)

- #10880: setting verbose > 2 in minimize with trust-constr method leads…

- #10887: scipy.signal.signaltools._fftconv_faster has incorrect estimates

- #10948: gammainc(0,x) = nan but should be 1, gammaincc(0,x) = nan but…

- #10952: TestQRdelete_F.test_delete_last_p_col test failure

- #10968: API: Change normalized=False to normalize=True in Rotation

- #10987: Memory leak in shgo triangulation

- #10991: Error running openBlas probably missing a step

- #11033: deadlock on osx for python 3.8

- #11041: Test failure in wheel builds for TestTf2zpk.test_simple

- #11089: Regression in scipy.stats where distribution will not accept loc and scale parameters

- #11100: BUG: multiscale_graphcorr random state seeding and parallel use

- #11121: Calls to `scipy.interpolate.splprep` increase RAM usage.

- #11125: BUG: segfault when slicing a CSR or CSC sparse matrix with slice start index > stop index

- #11198: BUG: sparse eigs (arpack) shift-invert drops the smallest eigenvalue for some k

## Pull requests for 1.4.0

- #4591: BUG, TST: Several issues with scipy.signal.residue

- #6629: ENH: sparse: canonicalize on initialization

- #7076: ENH: add complex wavelet support to scipy.signal.cwt.

- #8681: ENH add generalized inverse Gaussian distribution to scipy.stats

- #9064: BUG/ENH: Added default _transpose into LinearOperator. Fixes…

- #9215: ENH: Rbf interpolation of large multi-dimensional data

- #9311: ENH: Added voigt in scipy.special.

- #9642: ENH: integrate: quad() for vector-valued functions

- #9679: DOC: expand docstring of exponweib distribution

- #9684: TST: add ppc64le ci testing

- #9800: WIP : ENH: Refactored _hungarian.py for speed and added a minimize/maximize…

- #9847: DOC: Change integrate tutorial to use solve_ivp instead of odeint

- #9876: ENH: Use rfft when possible in resampling

- #9998: BUG: Do not remove 1s when calling sparse: reshape method #9994

- #10002: ENH: adds constraints for differential evolution

- #10098: ENH: integrate: add args argument to solve_ivp.

- #10099: DOC: Add missing docs for linprog unknown_options

- #10104: BUG: Rewrite of stats.truncnorm distribution.

- #10105: MAINT improve efficiency of rvs_ratio_uniforms in scipy.stats

- #10107: TST: dual_annealing set seed

- #10108: ENH: stats: improve kendall_tau cache usage

- #10110: MAINT: _lib: Fix a build warning.

- #10114: FIX: only print bounds when supported by minimizer (shgo)

- #10115: TST: Add a test with an almost singular design matrix for lsq_linear

- #10118: MAINT: fix rdist methods in scipy.stats

- #10119: MAINT: improve rvs of randint in scipy.stats

- #10127: Fix typo in record array field name (spatial-ckdtree-sparse_distance…

- #10130: MAINT: ndimage: Fix some compiler warnings.

- #10131: DOC: Note the solve_ivp args enhancement in the 1.4.0 release…

- #10133: MAINT: add rvs for semicircular in scipy.stats

- #10138: BUG: special: Invalid arguments to ellip_harm can crash Python.

- #10139: MAINT: spatial: Fix some compiler warnings in the file distance_wrap.c.

- #10140: ENH: add handling of NaN in RuntimeWarning except clause

- #10142: DOC: return value of scipy.special.comb

- #10143: MAINT: Loosen linprog tol

- #10152: BUG: Fix custom sampling input for shgo, add unittest

- #10154: MAINT: add moments and improve doc of mielke in scipy.stats

- #10158: Issue #6999: read zlib checksum before checking bytes read.

- #10166: BUG: Correctly handle broadcasted ydata in curve_fit pcov computation.

- #10167: DOC: special: Add missing factor of `i` to `modstruve` docstring

- #10168: MAINT: stats: Fix an incorrect comment.

- #10169: ENH: optimize: Clarify error when objective function returns…

- #10172: DEV: Run tests in parallel when –parallel flag is passed to…

- #10173: ENH: Implement DOP853 ODE integrator

- #10176: Fixed typo

- #10182: TST: fix test issue for stats.pearsonr

- #10184: MAINT: stats: Simplify zmap and zscore (we can use keepdims now).

- #10191: DOC: fix a formatting issue in the scipy.spatial module docstring.

- #10193: DOC: Updated docstring for optimize.nnls

- #10198: DOC, ENH: special: Make `hyp2f1` references more specific

- #10202: DOC: Format DST and DCT definitions as latex equations

- #10207: BUG: Compressed matrix indexing should return a scalar

- #10210: DOC: Update docs for connection=’weak’ in connected_components

- #10225: DOC: Clarify new interfaces for legacy functions in ‘optimize’

- #10231: DOC, MAINT: gpg2 updates to release docs / pavement

- #10235: LICENSE: split license file in standard BSD 3-clause and bundled.

- #10238: ENH: Add new scipy.fft module using pocketfft

- #10243: BUG: fix ARFF reader regression with quoted values.

- #10248: DOC: update README file

- #10255: CI: bump OpenBLAS to match wheels

- #10264: TST: add tests for stats.tvar with unflattened arrays

- #10280: MAINT: stats: Use a constant value for sqrt(2/PI).

- #10286: Development Documentation Overhaul

- #10290: MAINT: Deprecate NumPy functions in SciPy root

- #10291: FIX: Avoid importing xdist when checking for availability

- #10295: Disable deprecated Numpy API in __odrpack.c

- #10296: ENH: C++ extension for linear assignment problem

- #10298: ENH: Made pade function work with complex inputs

- #10301: DOC: Fix critical value significance levels in stats.anderson_ksamp

- #10307: Minkowski Distance Type Fix (issue #10262)

- #10309: BUG: Pass jac=None directly to lsoda

- #10310: BUG: interpolate: UnivariateSpline.derivative.ext is ‘zeros’…

- #10312: FIX: Fixing a typo in a comment

- #10314: scipy.spatial enhancement request

- #10315: DOC: Update integration tutorial to solve_ivp

- #10318: DOC: update the example for PPoly.solve

- #10333: TST: add tests for stats.tvar with unflattened arrays

- #10334: MAINT: special: Remove deprecated `hyp2f0`, `hyp1f2`, and…

- #10336: BUG: linalg/interpolative: fix interp_decomp modifying input

- #10341: BUG: sparse.linalg/gmres: deprecate effect of callback on semantics…

- #10344: DOC: improve wording of mathematical formulation

- #10345: ENH: Tiled QR wrappers for scipy.linalg.lapack

- #10350: MAINT: linalg: Use the new fft subpackage in linalg.dft test…

- #10351: BUG: Fix unstable standard deviation calculation in histogram

- #10353: Bug: interpolate.NearestNDInterpolator (issue #10352)

- #10357: DOC: linalg: Refer to scipy.fft.fft (not fftpack) in the dft…

- #10359: DOC: Update roadmap now scipy.fft has been merged

- #10361: ENH: Prefer scipy.fft to scipy.fftpack in scipy.signal

- #10371: DOC: Tweaks to fft documentation

- #10372: DOC: Fix typos

- #10377: TST, MAINT: adjustments for pytest 5.0

- #10378: ENH: _lib: allow new np.random.Generator in check_random_state

- #10379: BUG: sparse: set writeability to be forward-compatible with numpy>=1.17

- #10381: BUG: Fixes gh-7491, pdf at x=0 of fisk/burr/burr12/f distributions.

- #10387: ENH: optimize/bfgs: don’t evaluate twice at initial point for…

- #10392: [DOC] Add an example for _binned_statistic_dd

- #10396: Remove warning about output shape of zoom

- #10397: ENH: Add check_finite to sp.linalg.norm

- #10399: ENH: Add __round__ method to sparse matrix

- #10407: MAINT: drop pybind11 from install_requires, it’s only build-time…

- #10408: TST: use pytest.raises, not numpy assert_raises

- #10409: CI: uninstall nose on Travis

- #10410: [ENH] ncx2 dispatch to chi2 when nc=0

- #10411: TST: optimize: test should use assert_allclose for fp comparisons

- #10414: DOC: add pybind11 to the other part of quickstart guides

- #10417: DOC: special: don’t mark non-ufuncs with a `[+]`

- #10423: FIX: Use pybind11::isinstace to check array dtypes

- #10424: DOC: add doctest example for binary data for ttest_ind_from_stats

- #10425: ENH: Add missing Hermitian transforms to scipy.fft

- #10426: MAINT: Fix doc build bugs

- #10431: Update numpy version for AIX

- #10433: MAINT: Minor fixes for the stats

- #10434: BUG: special: make `ndtri` return NaN outside domain of definition

- #10435: BUG: Allow integer input data in scipy.stats.yeojohnson

- #10438: [DOC] Add example for kurtosis

- #10440: ENH: special: make `ellipk` a ufunc

- #10443: MAINT: ndimage: malloc fail check

- #10447: BLD: Divert output from test compiles into a temporary directory

- #10451: MAINT: signal: malloc fail check

- #10455: BUG: special: fix values of `hyperu` for negative `x`

- #10456: DOC: Added comment clarifying the call for dcsrch.f in lbfgsb.f

- #10457: BUG: Allow ckdtree to accept empty data input

- #10459: BUG:TST: Compute lwork safely

- #10460: [DOC] Add example to entropy

- #10461: DOC: Quickstart Guide updates

- #10462: TST: special: only show max atol/rtol for test points that failed

- #10465: BUG: Correctly align fft inputs

- #10467: ENH: lower-memory duplicate generator checking in spatial.SphericalVoronoi

- #10470: ENH: Normalise the inverse DCT/DST in scipy.fft

- #10472: BENCH: adjust timeout for slow setup_cache

- #10475: CI: include python debug for Travis-ci

- #10476: TST: special: use `__tracebackhide__` to get better error messages

- #10477: ENH: faster region building in spatial.SphericalVoronoi

- #10479: BUG: stats: Fix a few issues with the distributions’ fit method.

- #10480: Add RuntimeError in _distn_infrastructure.py in fit() method

- #10481: BENCH, MAINT: wheel_cache_size has been renamed build_cache_size

- #10494: ENH: faster circumcenter calculation in spatial.SphericalVoronoi

- #10500: Splrep _curfit_cache global variable bugfix

- #10503: BUG: spatial/qhull: get HalfspaceIntersection.dual_points from…

- #10506: DOC: interp2d, note nearest neighbor extrapolation

- #10507: MAINT: Remove fortran fftpack library in favour of pypocketfft

- #10508: TST: fix a bug in the circular import test.

- #10509: MAINT: Set up _build_utils as subpackage

- #10516: BUG: Use nogil contexts in cKDTree

- #10517: ENH: fftconvolve should not FFT broadcastable axes

- #10518: ENH: Speedup fftconvolve

- #10520: DOC: Proper .rst formatting for deprecated features and Backwards…

- #10523: DOC: Improve scipy.signal.resample documentation

- #10524: ENH: Add MGC to scipy.stats

- #10525: [ENH] ncx2.ppf dispatch to chi2 when nc=0

- #10526: DOC: clarify laplacian normalization

- #10528: API: Rename scipy.fft DCT/DST shape argument to s

- #10531: BUG: fixed improper rotations in spatial.transform.rotation.match_vectors

- #10533: [DOC] Add example for winsorize function

- #10539: MAINT: special: don’t register `i0` with `numpy.dual`

- #10540: MAINT: Fix Travis and Circle

- #10542: MAINT: interpolate: use cython_lapack

- #10547: Feature request. Add furthest site Voronoi diagrams to scipy.spatial.plotutils.

- #10549: [BUG] Fix bug in trimr when inclusive=False

- #10552: add scipy.signal.upfirdn signal extension modes

- #10555: MAINT: special: move `c_misc` into Cephes

- #10556: [DOC] Add example for trima

- #10562: [DOC] Fix triple string fo trimmed so that __doc__ can show…

- #10563: improve least_squares error msg for mismatched shape

- #10564: ENH: linalg: memoize get_lapack/blas_funcs to speed it up

- #10566: ENH: add implementation of solver for the maximum flow problem

- #10567: BUG: spatial: use c++11 construct for getting start of vector…

- #10568: DOC: special: small tweaks to the `zetac` docstring

- #10571: [ENH] Gaussian_kde can accept matrix dataset

- #10574: ENH: linalg: speed up _compute_lwork by avoiding numpy constructs

- #10582: Fix typos with typos in bundled libraries reverted

- #10583: ENH: special: add the analytic continuation of Riemann zeta

- #10584: MAINT: special: clean up `special.__all__`

- #10586: BUG: multidimensional scipy.fft functions should accept ‘s’ rather…

- #10587: BUG: integrate/lsoda: never abort run, set error istate instead

- #10594: API: Replicate numpy’s fftn behaviour when s is given but not…

- #10599: DOC: dev: update documentation vs. github pull request workflow…

- #10603: MAINT: installer scripts removed

- #10604: MAINT: Change c*np.ones(…) to np.full(…, c, …) in many…

- #10608: Univariate splines should require x to be strictly increasing…

- #10613: ENH: Add seed option for gaussian_kde.resample

- #10614: ENH: Add parallel computation to scipy.fft

- #10615: MAINT: interpolate: remove unused header file

- #10616: MAINT: Clean up 32-bit platform xfail markers

- #10618: BENCH: Added ‘trust-constr’ to minimize benchmarks

- #10621: [MRG] multiple stability updates in lobpcg

- #10622: MAINT: forward port 1.3.1 release notes

- #10624: DOC: stats: Fix spelling of ‘support’.

- #10627: DOC: stats: Add references for the alpha distribution.

- #10629: MAINT: special: avoid overflow longer in `zeta` for negative…

- #10630: TST: GH10271, relax test assertion, fixes #10271

- #10631: DOC: nelder-mean uses xatol fixes #10036

- #10633: BUG: interpolate: integral(a, b) should be zero when both limits…

- #10635: DOC: special: complete hypergeometric functions documentation

- #10636: BUG: special: use series for `hyp1f1` when it converges rapidly

- #10641: ENH: allow matching of general bipartite graphs

- #10643: ENH: scipy.sparse.linalg.spsolve triangular unit diagonal

- #10650: ENH: Cythonize sosfilt

- #10654: DOC: Vertical alignment of table entries

- #10655: ENH: Dockerfile for scipy development

- #10660: TST: clean up tests for rvs in scipy.stats

- #10664: Throw error on non-finite input for binned_statistic_dd()

- #10665: DOC: special: improve the docstrings for `gamma` and `gammasgn`

- #10669: TST: Update scipy.fft real transform tests

- #10670: DOC: Clarify docs and error messages for scipy.signal.butter

- #10672: ENH: return solution attribute when using events in solve_ivp

- #10675: MAINT: special: add an explicit NaN check for `iv` arguments

- #10679: DOC: special: Add documentation for `beta` function

- #10681: TST: sparse.linalg: fix arnoldi test seed

- #10682: DOC: special: Add documentation for `betainc` function

- #10684: TST: special: require Mpmath 1.1.0 for `test_hyperu_around_0`

- #10686: FIX: sphinx isattributedescriptor is not available in sphinx…

- #10687: DOC: added Docker quickstart guide by @andyfaff

- #10689: DOC: special: clarify format of parameters/returns sections for…

- #10690: DOC: special: improve docstrings of incomplete gamma functions

- #10692: ENH: higher-dimensional input in `spatial.SphericalVoronoi`

- #10694: ENH: ScalarFunction.fun_and_grad

- #10698: DOC: special: Add documentation for `betaincinv`

- #10699: MAINT: remove time print lbfgsb fixes #8417

- #10701: TST, MAINT: bump OpenBLAS to 0.3.7 stable

- #10702: DOC: clarify iterations consume multiple function calls

- #10703: DOC: iprint doc lbfgsb closes #5482

- #10708: TST: test suggested in gh1758

- #10710: ENH: Added nan_policy to circ functions in `stats`

- #10712: ENH: add axis parameter to stats.entropy

- #10714: DOC: Formatting fix rv_continuous.expect docs

- #10715: DOC: BLD: update doc Makefile for python version; add scipy version…

- #10717: MAINT: modernize doc/Makefile

- #10719: Enable setting minres initial vector

- #10720: DOC: silence random warning in doc build for `stats.binned_statistic_dd`

- #10724: DEV: Add doc option to runtests.py

- #10728: MAINT: get rid of gramA, gramB text files that lobpcg tests leave…

- #10732: DOC: add min_only to docstring for Dijkstra’s algorithm

- #10734: DOC: spell out difference between source and target in shortest…

- #10735: Fix for Python 4

- #10739: BUG: optimize/slsqp: deal with singular BFGS update

- #10741: ENH: LAPACK wrappers for ?geequ, ?geequb, ?syequb, ?heequb

- #10742: DOC: special: add to the docstring of `gammaln`

- #10743: ENH: special: add a real dispatch for `wrightomega`

- #10746: MAINT: Fix typos in comments, docs and test name

- #10747: Remove spurious quotes

- #10750: MAINT: make cython code more precise

- #10751: MAINT: Check that scipy.linalg.lapack functions are documented

- #10752: MAINT: special: use `sf_error` in Cephes

- #10755: DOC: cluster: Add ‘See Also’ and ‘Examples’ for kmeans2.

- #10763: MAINT: list of minimize methods

- #10768: BUG: Fix corner case for sos2zpk

- #10773: Fix error type for complex input to scipy.fftpack.rfft and irfft

- #10776: ENH: handle geodesic input in `spatial.SphericalVoronoi`

- #10777: MAINT: minimizer–>custom should handle the kinds of bounds/constrain……

- #10781: ENH: solve_triangular C order improvement

- #10787: Fix behavior of `exp1` on branch cut and add docstring

- #10789: DOC: special: add parameters/returns doc sections for erfc/erfcx/erfi

- #10790: Travis CI: sudo is deprecated and Xenial is default distro

- #10792: DOC: special: add full docstring for `expi`

- #10799: DOC: special: add a complete docstring for `expn`

- #10800: Docs edits (GSoD)

- #10802: BUG: fix UnboundLocalError in Radau (scipy#10775)

- #10804: ENH: Speed up next_fast_len with LRU cache

- #10805: DOC: Fix unbalanced quotes in signal.place_poles

- #10809: ENH: Speed up next_fast_len

- #10810: ENH: Raise catchable exceptions for bad Fortran files

- #10811: MAINT: optimize: Remove extra variable from _remove_redundancy_dense

- #10813: MAINT: special: Remove unused variables from _kolmogi and _smirnovi

- #10815: DOC, API: scipy.stats.reciprocal is “log-uniform”

- #10816: MAINT: special: remove deprecated `bessel_diff_formula`

- #10817: DOC: special: complete the docstring for `fresnel`

- #10820: Fixed compiler_helper.py to allow compilation with ICC on Linux

- #10823: DOC: updated reference guide text for consistency in writing…

- #10825: MAINT: special: change some features of the Voigt function

- #10828: MAINT: integrate: Remove unused variable from init_callback

- #10830: Adding LOBPCG solver in svds in addition to ARPACK

- #10837: WIP: ENH: reduction function for `spatial.tranform.Rotation`…

- #10843: ENH: Adding optional parameter to stats.zscores to allow for…

- #10845: Rebase kruskal fix

- #10847: remove redundant __getitem__ from scipy.sparse.lil

- #10848: Better handling of empty (not missing) docstrings

- #10849: ENH: implement rmatmat for LinearOperator

- #10850: MAINT : Refactoring lil List of Lists

- #10851: DOC: add a generative art example to the scipy.spatial tutorial.

- #10852: DOC: linalg: fixed gh-10838 unused imports in example deleted

- #10854: DOC: special: add a full docstring for `pdtr`

- #10861: ENH: option to reuse binnumbers in stats.binned_statistic_dd

- #10863: DOC: partial standardization and validation of scipy.stats reference…

- #10865: BUG: special: fix incomplete gamma functions for infinite `a`

- #10866: ENH: calculation of mean in spatial.transform.Rotation

- #10867: MAINT: Also store latex directory

- #10869: ENH: Implement overlap-add convolution

- #10870: ENH: Do not raise EOF error if wavfile data read

- #10876: ENH: Add beta-binomial distribution to scipy.stats

- #10878: MAINT: Update R project URL

- #10883: MAINT: (ndimage) More robust check for output being a numpy dtype

- #10884: DOC: Added instructions on adding a new distribution to scipy.stats.

- #10885: [BUG] fix lobpcg with maxiter=None results in Exception

- #10899: ENH: Match R functionality for hmean

- #10900: MAINT: stats: Use keepdims to simplify a few lines in power_divergence.

- #10901: ENH: sparse/linalg: support pydata/sparse matrices

- #10907: Check whether `maxiter` is integer

- #10912: ENH: warn user that quad() ignores `points=…` when `weight=…`…

- #10918: CI: fix Travis CI py3.8 build

- #10920: MAINT: Update constants to codata 2018 values (second try)

- #10921: ENH: scipy.sparse.lil: tocsr accelerated

- #10924: BUG: Forbid passing ‘args’ as kwarg in scipy.optimize.curve_fit

- #10928: DOC: Add examples to io.wavfile docstrings

- #10934: typo fix

- #10935: BUG: Avoid undefined behaviour on float to unsigned conversion

- #10936: DOC: Added missing example to stats.mstats.variation

- #10939: ENH: scipy.sparse.lil: tocsr accelerated depending on density

- #10946: BUG: setting verbose > 2 in minimize with trust-constr method…

- #10947: DOC: special: small improvements to the `poch` docstring

- #10949: BUG: fix return type of erlang_gen._argcheck

- #10951: DOC: fixed Ricker wavelet formula

- #10954: BUG: special: fix `factorial` return type for 0-d inputs

- #10955: MAINT: Relax the assert_unitary atol value

- #10956: WIP: make pdtr(int, double) be pdtr(double, double)

- #10957: BUG: Ensure full binary compatibility of long double test data

- #10964: ENH: Make Slerp callable with a scalar argument

- #10972: BUG: Handle complex gains in zpk2sos

- #10975: TST: skip test_kendalltau ppc64le

- #10978: BUG: boxcox data dimension and constancy check #5112

- #10979: API: Rename dcm to (rotation) matrix in Rotation class

- #10981: MAINT: add support for a==0 and x>0 edge case to igam and igamc

- #10986: MAINT: Remove direct imports from numpy in signaltools.py

- #10988: BUG: signal: fixed issue #10360

- #10989: FIX binned_statistic_dd Mac wheel test fails

- #10990: BUG: Fix memory leak in shgo triangulation

- #10992: TST: Relax tolerance in upfirdn test_modes

- #10993: TST: bump tolerance in optimize tests

- #10997: MAINT: Rework residue and residuez

- #11001: DOC: Updated Windows build tutorial

- #11004: BUG: integrate/quad_vec: fix several bugs in quad_vec

- #11005: TST: add Python 3.8 Win CI

- #11006: DOC: special: add a reference for `kl_div`

- #11012: MAINT: Rework invres and invresz

- #11015: DOC: special: add references for `rel_entr`

- #11017: DOC: numpydoc validation of morestats.py

- #11018: MAINT: Filter unrelated warning

- #11031: MAINT: update choose_conv_method for pocketfft implementation

- #11034: MAINT: TST: Skip tests with multiprocessing that use “spawn”…

- #11036: DOC: update doc/README with some more useful content.

- #11037: DOC: special: add a complete docstring for `rgamma`

- #11038: DOC: special: add a reference for the polygamma function

- #11042: TST: fix tf2zpk test failure due to incorrect complex sorting.

- #11044: MAINT: choose_conv_method can choose fftconvolution for longcomplex

- #11046: TST: Reduce tolerance for ppc64le with reference lapack

- #11048: DOC: special: add reference for orthogonal polynomial functions

- #11049: MAINT: proper random number initialization and readability fix

- #11051: MAINT: pep8 cleanup

- #11054: TST: bump test precision for dual_annealing SLSQP test

- #11055: DOC: special: add a reference for `zeta`

- #11056: API: Deprecated normalized keyword in Rotation

- #11065: DOC: Ubuntu Development Environment Quickstart should not modify…

- #11066: BUG: skip deprecation for numpy top-level types

- #11067: DOC: updated documentation for consistency in writing style

- #11070: DOC: Amendment to Ubuntu Development Environment Quickstart should…

- #11073: DOC: fix 1.4.0 release notes

- #11081: API: Replace Rotation.match_vectors with align_vectors

- #11083: DOC: more 1.4.0 release note fixes

- #11092: BUG: stats: fix freezing of some distributions

- #11096: BUG: scipy.sparse.csgraph: fixed issue #10774

- #11124: fix Cython warnings related to _stats.pyx

- #11126: BUG: interpolate/fitpack: fix memory leak in splprep

- #11127: Avoid potential segfault in CSR and CSC matrix indexing

- #11152: BUG: Fix random state bug multiscale_graphcorr

- #11166: BUG: empty sparse slice shapes

- #11167: BUG: redundant fft in signal.resample

- #11181: TST: Fix tolerance of tests for aarch64

- #11182: TST: Bump up tolerance for test_maxiter_worsening

- #11199: BUG: sparse.linalg: mistake in unsymm. real shift-invert ARPACK eigenvalue selection