CoolMind

If you cannot measure it, you cannot improve it.

Base64 in python

Base64 encode and decode are used in many places. What is base64 and how to implement base64 encode and decode in python? What is base64? How...

Posted by chunyang on March 18, 2022

Date and string format in python

在 Python 中生成字符串有 3 种方式，现在比较建议的是使用 f-str 的方式，官方说性能更加好。本文主要介绍在格式化时有哪些格式可以选择。 String % format f-str 进制转化 ...

Posted by chunyang on January 26, 2022

Python command line comparison

编写 Python 的命令行程序时，一个很重要的问题是：如何声明参数，然后解析，最终被程序调用。能否灵活的声明，组合会决定我们是否需要用额外的代码来替代这些功能。例如参数的互斥，子命令等。总结 argparse click Types Mul...

Posted by chunyang on November 10, 2021

Add Unique ID for Http Request

后端服务的每一次请求会进入各种逻辑，发生各种问题。在大并发情况下，不同请求之间的日志还会混在一起。背景唯一的 id 和日志模块合并具体案例背景为了便于查找和分析问题，一般我们需要识别每一次请求。有两种方式：用户请求都会有唯一的 id，例如支付宝...

Posted by chunyang on November 3, 2021

Who passes the additional argument to my `fn` ?

Recently in an implementation of a functionality, following error keeps showing and drives me crazy. Traceback (most recent call last): File "te...

Posted by chunyang on May 21, 2021

GeoHash algorithm

最近遇到一个问题：K 个距离最近商铺问题。用户实时汇报其坐标，需要返回距离其最近的 K 个商铺问题。方法一方法二在 8 个方向移动参考商铺的量很大，如果每次都遍历计算一遍计算复杂度很高。 class Shop { Pos pos; // ...

Posted by chunyang on March 1, 2021

Merge tensorflow models

Sometimes you want to transfer certain weights from multiple models into a single model or just want to merge multiple models. There are at least t...

Posted by chunyang on December 27, 2020

Estimator core in evaluator

记录另外一次 Estimator 的 core 排查。背景复现代码 Lessons learned 参考背景我们用户使用 Estimator 都是使用 chief + worker + ps + evaluator 的形式。在线上偶发的 evaluator 这...

Posted by chunyang on November 24, 2020