* rm retain grad

* fix zero_dim

* fix zero_dim for xpu

* reset zero dim for xpu

* reset xpu

* reset custom_relu

* Reset flip

* fix zero dim

* rm retain grads flag for tests

* modify fill_diagonal

* retain grads for fill_diagonal tests

* reset sum & concat

* fix fill_diagonal

* [CodeStyle][F811] fix some unittests

* fix setup.py

* remove ignore from flake8 config

* remove repeat TestAbsDoubleGradCheck

* fix rrelu test

* fix fft ut

* add noqa in fluid.lstm ut

* add rtol and atol in test_matmul_v2_op

* update rtol

* empty commit

* empty commit

* revert changes in matmul ut and add noqa

* rename test case name

* isort all files

* revert conflicting files

* revert conflicting files

* revert conflicting files

* revert conflicting files

* revert conflicting files

* remove apis in fluid.ops

* fix test_activation_nn_grad

* fix circle import error

* fix ops

* fix cos

* fix divide not inplace

* remove lazy-import part

* support pow_double_grad op

* add unit test for pow double grad

* fix pow double grad

* optimize pow double grad kernel

* fix pow double grad kernel

* add sin double grad operator

* add sin double grad test example

* move sindoublegradopmaker to backward.yaml

* fix sindoublegrad code

* simplify sindoublegrad functor

* update config

* re-blacken python code

* temporarily disable date and diff_py_file

* skip a format

* [CodeStyle] remove all future import

* revert test_error.py

* restore future import in example code

* use yapf to format all python file

* yapf exclude two unittests file for they rely on writing and reading file, and format will break them

* disable diff_py_file because too many diff files cause command following failed

* [Eager] FLAGS_retain_grad set false

* Add FLAGS_retain_grad_ for some tests

* Add FLAGS_retain_grad_ to some tests

* modified set_flags

* modified set_flags

* fix windows-ci and windows-openblas-ci

* import paddle.fluid

* add double grad yaml

* fix bugs when compile infrt

* add abs double grad yaml and test case

* add pool2d double grad yaml

* add pool2d dygraph double grad test case

* add double yaml

* add inline func

* Support double grad check of op in Eager mode

* fix bugs of backward yaml

* adjust code format

This reverts commit 05f3d48e.

This reverts commit e77a947e.

* update

* add forward case

* update

* update; test=develop

* add some grad kernel; test=develop

* move gpu kernel; test=develop

* update

* update;

* update test;

* fix selected rows bug;

* add mix vector include ;

* add mixed vector depen; test=develop

* add logit grad signature;

* polish code

* fix bug;

* add namespace for abs

* revert code

* not move softsign

* revmove duplate register;

* fix softsign bug

* polish code

* format

* format

* fix bug

* remove cmake dep

* add square sqrt selected rows support

* update

* remove clip norm

* add standalone executor sqrt dep

* standalone exec denp sqrt

* remove sqrt op in cmkaelist

* open some case

* native commit for triple grad of sigmod

* Updated unittests files

* init functional jacobian api

* Updated trible_test func

* Updated gradient_checker & test_script

* finish test with dtype float32

* add float64 test case

* polish code

* use atol=1e-5 with dtype float64

* fix for ci

* set timeout for test_jacobian

* fix dygraph grad to support high differential

* polish API docstring

* Updated gradient checker and some related files

* fix double grad strip error for high differential

* fix double grad strip error for high differential

* Add Sigmoid triple grad tests

* fix dygraph double grad dtype error when calling for high differential senario

* Updated triple grad teses func

* Use np.random to initialize ddx

* Updated triple_grad_check func

* add todo for gradient checker and refine some comments

* remove additional code

* add test for warnging in backward.py

* add tanh triple grad

* format python code

* refine code
Co-authored-by: Nveyron95 <veyron_wu@163.com>
Co-authored-by: Nlevi131 <limaolin01@baidu.com>

* update

* update

* update

* try make CI pass

* doc typo

* update doc string

* native commit for triple grad of sigmod

* Updated unittests files

* init functional jacobian api

* Updated trible_test func

* Updated gradient_checker & test_script

* finish test with dtype float32

* add float64 test case

* polish code

* use atol=1e-5 with dtype float64

* fix for ci

* set timeout for test_jacobian

* fix dygraph grad to support high differential

* polish API docstring

* Updated gradient checker and some related files

* fix double grad strip error for high differential

* fix double grad strip error for high differential

* Add Sigmoid triple grad tests

* fix dygraph double grad dtype error when calling for high differential senario

* Updated triple grad teses func

* Use np.random to initialize ddx

* Updated triple_grad_check func

* add todo for gradient checker and refine some comments

* remove additional code

* add test for warnging in backward.py

* format python code
Co-authored-by: Nveyron95 <veyron_wu@163.com>
Co-authored-by: Nlevi131 <limaolin01@baidu.com>

Sigmoid: Out = Sigmoid(X)
SigmoidGrad: DX = DOut*(1-Out)*Out

[This Patch]
Out
DOut -> SigmoidGradGrad -> DOutNew
DDX                        DDOut

DDOut = (1-Out)*Out*DDX
DOutNew = (1-2*Out)*DOut*DDX

* add IsInitialized

* rm additional log and add tanh double grad

* rename is_initialized

* fix elugradgrad test fail and error message opt

* fix unitest,test=develop

* Update prroi_pool_op.h

fix error message

* opt message,test=develop

* fix ci fail,test=develop

fix abs double grad unittest & define the data range for the abs double grad

register log double grad kernel for cpu and cuda

add abs support double grad for the api 2.0

* set esp as 1e-6 to solve elu unitest fail,test=develop

* support elu activation double grad,test=develop

* delete the code commit in .cc,test=develop

* fix relu test unpass, test=develop

* add elu double grad kernel and unit test

* add caculate dX in elu double grad functor, test=develop

* update the commit code,test=develop