CMCDragonkai

Creating a new Stack Project in a Nix Shell

There are so many different ways of building and maintaining Haskell projects.

I'm going to talk about using nix-shell and stack.

First you want a ~/.stack/config.yaml:

 local-bin-path: /home/USERNAME/.stack/bin

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l = [
    [1,2,3,4],
    [5,6,7,8],
    [9,10,11,12]
]

# the result shape will always produce from shortest row
lt = list(map(list, zip(*l)))

# [

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#!/usr/bin/env bash

text=(
  'a'
  'b'
)

IFS=: eval 'text="${text[*]}"'

echo "$text" # a:b

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import argparse
import logging


def verbose_to_loglevel(c):
    loglevel = logging.WARNING
    if c == 1:
        loglevel = logging.INFO
    elif c >= 2:
        loglevel = logging.DEBUG

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Conversion between Coordinate Origins

• T - Top
• B - Bottom
• L - Left
• R - Right

Remember that images loaded into a matrix uses the height as rows and width as columns. So x,y coordinates are flipped y,x to get i,j coordinates.

Subpixel Coordinates

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import random

def sample_reservoir(size, samples):
    reservoir = [None] * size
    k = size - 1
    for i in range(size):
        reservoir[i] = samples[i]
    for i in range(k + 1, len(samples)):
        j = random.randint(0, i)
        if j <= k:

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import os
import contextlib


@contextlib.contextmanager
def jumpdir(path):
    old_dir = os.getcwd()
    os.chdir(path)
    try:
        yield

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from sortedcontainers import SortedDict

def resolve_mask_occlusions(mask, z_index):
    if (len(mask.shape) != 3 or mask.shape[2] != len(z_index)):
        raise TypeError('Mask shape depth must match the z_index')
    z_index_map = SortedDict()
    for mask_index, mask_depth in enumerate(z_index):
        if mask_depth in z_index_map:
            z_index_map[mask_depth].append(mask_index)
        else:

CMCDragonkai

Python Setuptools

Python setuptools package replaces the distutils package. You use this in order to allow your Python package to be redistributable. Not just for PyPi but also for source distributions or private distributions.

First you need a setup.py at your project root:

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