* add LogNormal API

* fix bug

* fix bug

* fix bug

* fix bug

* fix bug

* fix bug

* fix bug

* fix bug

* fix bug

* fix bug

* fix bug

* add comment

* fix bug

* fix docs

* fix bug

* fix bug

* fix bug

* add test

* add test

* change the args type of Normal sample

* fix bug

* fix bug

* fix bug

* fix bug

* add test

* add test

* format

* add comment

* add comment

* add comment

* add comment

* format code

* fix bug

* fix bug

* fix bug

* add comment

* remove name parameter for LogNormal

* organize imports

* [CodeStyle] remove all future import

* revert test_error.py

* restore future import in example code

* 增加ks-test；注册kl_divergence

* bug fix

* bug fix data shape

* 按要求修改

* sample code fix

* 按要求修改

* bugfix

* bugfix

* bugfix

* bugfix

* bugfix

* fix sample func

* fix sample func

* 按要求修改；sample函数bugfix

* 按要求修改；sample函数bugfix

* bugfix

* 补充英文文档公式

* 英文文档bugfix

* bugfix

* bugfix

* 英文文档修复

* 去除name参数

* trim trailing whitespace

* fix `.cmake-format.py`

* revert npu ut changes, avoid npu ci error

* [Eager] Cast,uniform_random,assign_value use final state

* fix mistake

* fix mistake

* fix CI errors

* add dygraph test for unform

* add fp16 test case for bilinear_initializer

* cmake-lint

* update

* 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

* add random varaiable transformations API for paddle's distribution package

* add TransformedDistribution API for paddle's probability distribution package

* add random variable transformation unitests for static graph

* replace math.prod which not support python3.7 with functools.reduce

* add Independent and TransformedDistribution distribution

* add unittests for constraint

* fix typo and AffineTransform sample code error

* add mean,variance,rsample abstract method for Distribution

* switch eager mode and change it

* set default is eager

* set default is eager

* fix error; test=develop

* fix some error; test=develop

* update

* upd

* update code; test=develop

* update

* fix some bug; test=develop

* fix bug; test=develop

* fix bug; test=develop

* fix bug; test=develop

* fix error; test=develop

* format; test=develop
Co-authored-by: NJiabinYang <360788950@qq.com>

* add multinomial probability distribution
* fix categorical sample bug when logits less than zero
* fix categorical sample can't pass hypothesis test and entropy shape error bug

* add beta distribution
* add kl_divergence and register_kl api

* extend Distribution baseclass for supporting multivariant distribution and prob method

* add ExponentialFamily base class and entropy using Bregman divergence

* add dirichlet probability distribution

* add dirichlet sample op and cpu backend kernel

* add Dirichlet op cuda kernel  (#6)

* add dirichlet op hip kernel
Co-authored-by: NFeiyu Chan <chenfeiyu@baidu.com>

move distribution.py into distribution package and split into different file for better scalability (#38047)