Long ago, the first time I read "The Pragmatic Programmer", I read some advice that really stuck with me.
"Don't Use Manual Procedures".
This in the chapter on Ubiquitous Automation. To summarize, they want you to automate all the things.
The trouble was that I hadn't much of an idea how to actually go
Sometimes a python script will simply hang forever with no indication of where things went wrong. Perhaps it's polling a service that will never return a value that allows the program to move forward. Here's a way to see where the program is currently stuck.
Install gdb.
# Redhat, CentOS, etc
| import cv2 | |
| import subprocess | |
| ### for reference, the output of v4l2-ctl -d /dev/video1 -l (helpful for min/max/defaults) | |
| # brightness (int) : min=0 max=255 step=1 default=128 value=128 | |
| # contrast (int) : min=0 max=255 step=1 default=128 value=128 | |
| # saturation (int) : min=0 max=255 step=1 default=128 value=128 | |
| # white_balance_temperature_auto (bool) : default=1 value=1 | |
| # gain (int) : min=0 max=255 step=1 default=0 value=0 | |
| # power_line_frequency (menu) : min=0 max=2 default=2 value=2 |
| """ | |
| A slightly more convenient alternative to the builtin `sorted()` which allows | |
| you to specify a key as something other than a function. | |
| For example, with a list of lists, if you wanted to sort by the last element you | |
| could use `sort(lstseq, key=-1)` rather than `sorted(lstseq, key=lambda x: x[-1])`. | |
| If your key *is* a function, it behaves identically to `sorted()`, because it is | |
| really just wrapping the builtin. | |
| Examples | |
| -------- |
| /***************************************************************************** | |
| * QuantCup 1: Price-Time Matching Engine | |
| * | |
| * Submitted by: voyager | |
| * | |
| * Design Overview: | |
| * In this implementation, the limit order book is represented using | |
| * a flat linear array (pricePoints), indexed by the numeric price value. | |
| * Each entry in this array corresponds to a specific price point and holds | |
| * an instance of struct pricePoint. This data structure maintains a list |
| """Setting up the local environment.""" | |
| import itertools | |
| import numpy as np | |
| import matplotlib as mpl | |
| import matplotlib.pyplot as plt | |
| from functools import reduce |
| Screen { | |
| overflow: auto; | |
| } | |
| #calculator { | |
| layout: table; | |
| table-size: 4; | |
| table-gutter: 1 2; | |
| table-columns: 1fr; | |
| table-rows: 2fr 1fr 1fr 1fr 1fr 1fr; |
