Django Custom Lookups

This article is based on my Stackoverflow answer - Django query lookup 'startswith' on table fields.

Let's say you have a table of partial postal codes:

| codes  |
----------
| A1A |

oscarychen / remove_git_history.md

Last active September 30, 2021 17:25

Remove files from git commit history

Removing files from Git commit history

Clone a fresh copy of the repository using ssh and --mirror flag git clone --mirror git://example.com/some-big-repo.git

Download the bfg.jar file from BFG Repo-cleaner

Run BFG on the repo: java -jar bfg.jar --delete-files "*.csv" some-big-repo.git

oscarychen / conda_environments_jupyter_notebook.md

Last active February 15, 2022 17:22

Using Conda Environments with Jupiter Notebook

Using Conda environments in Jupyter Notebook

Create a Conda environment conda create -n py38 python=3.8

Activate the environment conda activate py38

Install ipykernel pip install --user ipykernel

oscarychen / ssh_for_git.md

Last active December 16, 2021 19:16

Setting up SSH for git

Setting up SSH for Git

General set-up for Git/Github account

Generally from a development machine, you would want to set up a ssh key that allows you to access your entire Github account, and access all of the repos under that account, here is how you can do that.

Generate a ssh key to be used from your machine to access your entire Github account: ssh-keygen -t rsa -b 4096 -C "[email protected]" When prompted "Enter file in which to save the key", you can specify something like: /Users/<username>/.ssh/github This should result in a private and public key pair being created:

oscarychen / python_on_mac_m1.md

Last active December 8, 2022 00:01

Setting up Python on Apple M1 (July 2021)

Setting up Python, XGBoost, Scipy on M1 Mac (July 2021)

As of July 2021, installing Python Xgboost on the M1 Macs is still confusing. The Python Xgboost library relies on Scipy, which requires a Fortran compiler, which is not available because GCC is not yet available for M1 (while Scipy does not support Flang). You may succeed in installing Python xgboost library without doing what I have described below and yet encounter issue running the library. I find the easiest thing currently is to just run Terminal with Rosetta, and go from there...

Get Terminal to run in Rosetta emulated X86 mode

Navigate to the Terminal app in Applications folder (sometimes it might be in Applications/Utilities)
Right click on the Terminal app -> Get Info -> Check Open using Rosetta
Optionally, you can duplicate the Terminal app, and rename the new one to something different, such as Terminal Rosetta and only make the duplicated app run in Rosetta mode

Install brew:

oscarychen / gitbash_on_windows.md

Last active November 2, 2021 21:45

Gitbash for Python on Windows

Setting up Gitbash, Terminal on Windows

Using Python from Anaconda:

Download and install Anaconda. Highly recommended to install Anaconda for current user instead of all users.
Create or modify your .bashrc file, at a location like:

C:\Users\oscar\.bashrc

Add a line that points to the path of Anaconda script, like the following:

Oscar Y Chen oscarychen