From d5139f0a4d7d214f4cbf6b35d5b27932f088aa77 Mon Sep 17 00:00:00 2001
From: YuRonan <471254751@qq.com>
Date: Fri, 14 Oct 2022 15:07:16 +0800
Subject: [PATCH] Update 20220908_api_design_for_gumbel.md (#298)

add cdf function for gumbel
---
 rfcs/APIs/20220908_api_design_for_gumbel.md | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/rfcs/APIs/20220908_api_design_for_gumbel.md b/rfcs/APIs/20220908_api_design_for_gumbel.md
index 647bde363..94f559e52 100644
--- a/rfcs/APIs/20220908_api_design_for_gumbel.md
+++ b/rfcs/APIs/20220908_api_design_for_gumbel.md
@@ -25,6 +25,7 @@
 - `rsample` 重参数化采样；
 - `prob` 概率密度；
 - `log_prob`对数概率密度；
+- `cdf`累积分布函数；
 - `entropy` 熵计算；
 
 ## 3、意义
@@ -533,6 +534,11 @@ exp(-(value - self.loc) / self.scale - exp(-(value - self.loc) / self.scale)) /
 np.log(self.probs(value))
 ```
 
+- cdf(value)：累积分布函数
+```python
+paddle.exp(-paddle.exp(-(value - self.loc) / self.scale))
+```
+
 - entropy(scale)：熵
 ```python
 self.scale.log() + (1 + np.euler_gamma)