[MySQL] Error establishing a database connection

太久沒有管 MySQL 就會有奇怪的問題, 所以也不太確定問題的由來, 只能用土法解決

InnoDB: The error means the system cannot find the path specified.
InnoDB: If you are installing InnoDB, remember that you must create
InnoDB: directories yourself, InnoDB does not create them.
InnoDB: Error: could not open single-table tablespace file ./mysql/innodb_index_stats.ibd
InnoDB: We do not continue the crash recovery, because the table may become
InnoDB: corrupt if we cannot apply the log records in the InnoDB log to it. 
InnoDB: To fix the problem and start mysqld:
InnoDB: 1) If there is a permission problem in the file and mysqld cannot
InnoDB: open the file, you should modify the permissions.
InnoDB: 2) If the table is not needed, or you can restore it from a backup,
InnoDB: then you can remove the .ibd file, and InnoDB will do a normal
InnoDB: crash recovery and ignore that table.
InnoDB: 3) If the file system or the disk is broken, and you cannot remove
InnoDB: the .ibd file, you can set innodb_force_recovery > 0 in my.cnf
InnoDB: and force InnoDB to continue crash recovery here.

先直接講解法好了, 就是在 my.cnf 多設定一行
nnodb_force_recovery = 1

重啟 MySQL 後再註解掉就可以了


參考: http://linux-server-tutorial.blogspot.tw/2014/02/mysql-is-not-starting-operating-system.html

[Python] Logging

這幾篇可以參考
https://stackoverflow.com/questions/15727420/using-python-logging-in-multiple-modules
https://gist.github.com/st4lk/6287746

[Python] Design in Python

這篇的範例簡單易懂
https://github.com/faif/python-patterns

[RPi] Duckietown

Duckietown an Open, Inexpensive and Flexible Platform for Autonomy Education and Research
http://duckietown.nctu.edu.tw/materials/paull-2017-icra-duckietown.pdf

這也有翻譯欸
http://blog.csdn.net/robocoder/article/details/53098753

[資訊科學] 如何在嵌入式系統中使用 IMU (加速度計與陀螺儀)

A Guide To using IMU (Accelerometer and Gyroscope Devices) in Embedded Applications.

有人翻譯了這篇文章, 紀錄一下
http://silverwind1982.pixnet.net/blog/post/280287502

[Python] 用 NumPy 做影像處理

這兩篇寫得很好
http://www.jianshu.com/p/6dcb1c1af2a7
http://www.jianshu.com/p/f8811ecf14f7

看來也是參考別人的
http://www.degeneratestate.org/posts/2016/Oct/23/image-processing-with-numpy/

這篇是慢動作做2D的convolution
http://www.songho.ca/dsp/convolution/convolution2d_example.html

從定義開始講起
http://www.songho.ca/dsp/convolution/convolution.html

[資訊科學] Convolution(卷積)

視覺化 convolution 和 cross-correlation
 https://www.youtube.com/watch?v=Ma0YONjMZLI

這篇的圖文也不錯,
http://mengqi92.github.io/2015/10/06/convolution/

這篇是慢動作教學,
https://stackoverflow.com/questions/20036663/understanding-numpys-convolve

https://dsp.stackexchange.com/questions/2654/what-is-the-difference-between-convolution-and-cross-correlation