algal

:;exec emacs --no-init-file --no-site-lisp -script "$0" -- "$@" # -*- mode:emacs-lisp -*-
(defun main ()
  (require 'cl-lib)
  (let ((script-name (nth 2 command-line-args))
        (args (cdr command-line-args-left)))
    ;; assert: ARGS now is a possibly empty list of command line args to the script

    ;; check for valid arguments here
    (when (not args)
      (princ (format "usage: %s PATH_TO_FILE" script-name))

algal

# binomial coefficients

"""
Recurrence relation:
	C(n,k) is the count of all k-subsets in a set of n items.
	C(n,k) = C(n-1,k-1) + C(n-1,k)
	
Intuition underlying the relation:
		1. pick any item from the n-set, call it the special item.
		2. Every k-subset either includes the special item or does not.

algal

24 bit color in emacs, under Blink.sh

What's the problem?

The normal way to enable 24 bit color on a recent emacs (27.1) and a recent OS distribution (one which already has the terminal type definition xterm-direct), is just to set TERM=xterm-direct before running emacs.

But this does not work with blink.sh, probably because of some incompatibility in its underlying library, hterm.

What's the solution

algal

extension Collection {
  /// True if `self` is a range within `collection`
  /// - Parameter collection: a `Collection` like `Array`
  /// - Returns: true or false
  ///
  /// Since this works with `Collection` it works with `Array`, `ArraySlic`, etc..
  func isSubcollection<U>(of collection:U) -> Bool
  where U:Collection, U.Element == Self.Element, Self.Element:Equatable
  {
    let (a,b) = (collection,self)

algal

#!/bin/bash
if [ "$#" -lt 2 ]; then
    echo "usage: $0 output_pdf_path input_path1..."
    echo
    echo "This script joins the PDFs at input_path1, input_path2, etc."
    echo "into one pdf at output_pdf_path"
    echo
    echo "Known good: macOS 11.1, and below for many versions"
    echo
    exit 1

algal

#!/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

# 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

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

' 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, "-", "")

algal

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: