* add new api/op kthvalue

* kthvalue cuda kernel to cub sorting

* fix example code error

* throw errors instead of LOG in cuda sort

* throw errors by Paddle_ENFORCE

* add new api paddle.quantile and paddle.Tensor.quantile

* add take_todo and fix UT

Paddle new APIs: put_along_axis.

Xu Huang is on holiday so we created this PR to work on it. It is based on his PR: https://github.com/PaddlePaddle/Paddle/pull/37921

* add new OP mode

* rename trans-variable name and fix UT

* add cpu kernel of lstsq

* update

* modify code style

* modify unittest

* remove support for complex

* add API and op for take_along_axis

* fix compile dependency problem and add example code and doc

* add unitest

* delete some code for CI coverage

* fix code style problem

* fix as review

* add amax/amin

* support axis is list

* add nansum api

* delete layerhelper

* add nansum to all and tensor_method_func

* update doc

* update doc

* update doc

* add new API/OP:paddle.Tensor.exponential_

* fix CI

* add new API/OP:paddle.poisson

* fix comment

* add control/status API, test=develop

* fix import error, test=develop

* add is_grad_enabled unittest, test=develop

* add code comment for example code and API, test=develop

* add checking for type, test=develop

* add api description, test=develop

* fix docs index_en, test=document_fix

* fix doc of is_floating_point, test=document_fix

* add erfinv API, test=develop

* fix gradient accuracy error, test=develop

* fix cuda compilation error on Windows, test=develop

* fix M_2_SQRTPI undeclared identifier on Windows, test=develop

* add complex op and `paddle.complex`.

* add activation

* update activation_op

* add unitest for activation

* fix acosh for init, test=develop

Add elementwise_fmax and elementwise_fmin operators

* add new API:paddle.movedim/moveaxis

* add new API:paddle.movedim/moveaxis

* add new API:add new API:paddle.movedim/moveaxis

* fix comment

* fix comment

* add Logit API

* add unittest

* conflict

* pull conflit

* pull conflit logit

* fix unititest

* fix code style

* update docs style of

* update en doc

* fix docs en style

* fix docs en style1

* fix docs en style2

* fix docs en style3

* fix docs en style4

* fix docs en style5

* fix docs en style6

* fix docs en style7

* fix docs en style8

* update by review

* fix nan bug

* add as_complex and as_real op

* save temp

* add unittest, test=develop

* fix ci error, test=develop

* fix grad accuracy error, test=develop

* fix unused error, test=develop

* fix compilation error on Windows, test=develop

* add unittest, test=develop

* modify by review comment and add lerp_

* fix inplace api, test=develop

* fix inplace api, test=develop

* fix coverage error, test=develop

* update

* update. test=develop

* fix. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix ut. test=develop

* update. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix sample code. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix ut. test=develop

* fix paddle.rot90 doc. test=develop

* update ut. test=develop

* fix. test=develop

* fix .test=develop

* fix .test=develop

* fix doc. test=develop

* add angle_op

* add diff op, test=develop

* rm some notes, test=develop

* update diff doc

* update sample code

* fix diff api params and example code, test=develop

* add isclose op, test=develop

* add isclose op, test=develop

* add isclose api, test=develop

* rm useless code

* rm useless code

* update python api of isclose

* add some unittest of isclose op, test=develop

* add randint like

* rm .cc .cu

* Update unity_build_rule.cmake

* try to make test pass

* use python

* update

* update randint_like

* rename test_randint_like_op -> test_randint_like

* update

* update randint like docs

* update randint like

* update

* update

* add bool

* update randint like test

* update

* update

* add new API: paddle.linalg.triangular_solve

* add new API/OP: paddle.linalg.triangular_solve

* add new API/OP: paddle.linalg.triangular_solve

* fix comment

* add eigvalsh with is_test

* add eigvalsh op

* fix backward bug

* forward and backward, float and complex, unittest

* remove eigvalsh_helper.h

* remove changes of cusolver.h

* fix unittest

* fix unittest bug

* update code following eigh

* fix test

* update lapack

* pull develop

* update funcor

* fix unittest bug

* fix details

* add tensor_method_func

* fix notes

* move signal apis

* move fft.py and signal.py to paddle/, fix typos

* fix relative imports from fft.py and signal.py

* fix typos

* Add bincount op

* upload cpu version

* fix unitest

* fix unittest

* fix unittest

* fix en doc

* add more test

* fix en doc

* add more test case

* fix test

* fix input vailidation

* fix input check

* fix unittest

* fix test

* fix en doc

* Add QR decomposition op

* Change codes to adapt to new svd_helper

* Update linalg.py

Restore the deleted comma

* Restore the deleted line

* Update linalg.py

* Update linalg.py

* Improve the qr code by reviews

* Update QR based on CI results

* Update qr doc, test=document_fix

* Change unsafe and ill-formed codes

* Add new API tensordot

* Set timeout value 400 for UT; Fix format for EN docs

* Set timeout value 1000 for UT; Fix format for EN docs

* Remove some input check

* Coding style improve: don't compare boolean values to True or False
using ==

* Add paddle.linalg.eig op

* remove comments

* remove comments

* extend batch_size to the origin

* add real times complex functor & destroy the backward complex output bug

* terminate output diff when input real tensors

* correct tiny doc errors

* move functions from eig_helper to svd_helper and remove eig_helper

* remove tensor.Resize

* remove no longer used code

* use existing lapack functions

* reply review comments 21/27

* remove .cu as this op is only executed on CPU

* remove const_cast & add const in argument list for read-only references

* fix sample code error in CI

* remove template typename Tbase and more

* remove eig exposure in paddle.*

* add 'name=None' in eig python implementation

* handle the unittest

* try to solve the unittest

* solve CI coverage

* remove no longer used code

* polish API doc and more

* reply review comments

* polish unittest, commit plan B

* polish unittest