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Alexis Gallagher algal

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algal / join_pdf.bash
Last active Feb 16, 2021
join PDFs on macOS from the command line with zero dependencies
View join_pdf.bash
if [ "$#" -lt 2 ]; then
echo "usage: $0 output_pdf_path input_path1..."
echo "This script joins the PDFs at input_path1, input_path2, etc."
echo "into one pdf at output_pdf_path"
echo "Known good: macOS 11.1, and below for many versions"
exit 1
algal / mdfindfile
Last active Nov 12, 2020
Easily search for files based their names or glob patterns, by wrapping Spotlight.
View mdfindfile
#!/usr/bin/env bash
# case-insensitive search for $1, maybe in dir $2
case "$#" in
0) echo "usage: $(basename $0) PATTERN [DIR]"
echo ""
echo " Lists paths of files matching PATTERN in DIR or below"
1) exec mdfind "kMDItemDisplayName == '$1'c"
*) exec mdfind "kMDItemDisplayName == '$1'c" -onlyin "$2"
algal /
Created Sep 9, 2020
Plot a confusion matrix in scikitlearn from data not from an estimator
# This uses scikit learn internals, since the sk public API requires you to pass
# in an estimator and sometimes you just want to pass in the some data you'd
# use to calculate a raw CM
def plot_cm(y_true,y_pred,labels):
from sklearn.metrics._plot.confusion_matrix import ConfusionMatrixDisplay
sample_weight = None
normalize = None
include_values = True
algal /
Created Aug 29, 2020
To use an SFUSD Gmail account to subscribe to a non-SFUSD Google Calendar

Subscribing to a Google Calendar from an SFUSD Google Account

SFUSD Google accounts can only send and receive emails from SFUSD teachers, so they cannot receive calendar invitations from normal gmail accounts, like the gmail accounts of their parents. So you cannot invite them to join a calendar as usual.

Here's a workaround.

In the normal gmail account:

  1. Create the calendar to share from a normal gmail account.
  2. Go to Calendar Settings / General
algal / excel_parseDates.vba
Last active Sep 5, 2020
please god why aren't these predefined?
View excel_parseDates.vba
' Expects a datetimestr in the format "YYYYMMDD" with - or / or no separator
' Parses independently of local region, unlike VBA.DateTime.DateValue()
' Known-good on Excel for Mac Version 16.4
Function parseYYYYMMDD(dateTimeStr As String) As Date
Dim normalized As String
normalized = VBA.Strings.Trim(dateTimeStr)
normalized = VBA.Strings.Replace(dateTimeStr, "/", "")
normalized = VBA.Strings.Replace(normalized, "-", "")
from typing import Dict, List, Tuple
def makeKeyDict(items:List[Tuple]) -> Dict:
"Gives a list of tuples (a,b), returns a dict mapping a to set of b"
d = {}
for (a,b) in items:
d[a] = set([b]).union(d.get(a,set()))
return d
def findKeysWithMultipleValues(keydict) -> List:
algal /
Created Jul 28, 2020
Read file paths, names, hashes into a data frame
from import * # to get L
import pandas as pd
def readMD5file(md5path:Path) -> pd.DataFrame:
Generate MD5 output file by doing a search like:
find /home/jupyter/data/foldersToAdd/ -iname '*jpg' -print0 | xargs -0 -n 100 md5sum >> /home/jupyter/data/foldersToAdd.md5.out
algal / addWideMargins.bash
Created Jul 15, 2020
Add wide margins to a PDF for annotations
View addWideMargins.bash
if [ "$#" -ne 1 ]; then
echo "usage: $0 PDF_filename..."
echo "This script takes a PDF file as command line arguments,"
echo "and generates a new, landscape-formatted PDF file, where every "
echo "page has very large margins which may be useful for editorial notes"
echo "Requires: pdfjam"
algal / ReverseH2.swift
Last active Jun 22, 2020
Deno and Swift scripts to reverse H2 headers in text
View ReverseH2.swift
Reads stdin, requiring UTF8-encoded text.
Parses it as initial text followed by a sequence of H2 markdown blocks.
Prints to stdout the initial text plus the H2 blocks in reversed order.
import Foundation
algal / colorize-emacs.bashsource
Last active Feb 16, 2021
Setting up truecolor (24 bit color) in emacs in the terminal, under iTerm2
View colorize-emacs.bashsource
# sourcing this file will define a bash functions that
# tries to run subsequent calls to emacs with 24 bit color.
# It sets TERM to xterm-24bit if we're running in iTerm2
# and we've created a user-local terminfo record for xterm-24bit
# This will cause emacs to use 24 bit color only when it will work,
# inside or outside of tmux
# details: