outline

# Use bash or zsh, not csh/tcsh

# Basic commands:

cat greenEggsAndHam
less greenEggsAndHam

# meta-dot

grep ham greenEggsAndHam
grep ham greenEggsAndHam|awk '{print $1}
cat greenEggsAndHam|awk '/ham/ {print $1}'

# Build up to:

cat greenEggsAndHam|tr 'A-Z' 'a-z'|sed 's/[^a-z]/ /g'|tr ' ' '\n'|grep .|sort|uniq -c|sort -n

# counting line lengths:

cat greenEggsAndHam|while read line; do echo $line|wc -w; done|sort|uniq -c|sort -k2

# Election forecast

open https://projects.fivethirtyeight.com/2020-election-forecast/

fx 538.har
cat 538.har \
    |jq -r '.log.entries[]|select(.response.headers|contains([{"name": "content-type", "value": "application/json"}]))|.request.url'
jq -r '.log.entries[].request.url' 538.har |grep '\.json'

mkdir
for url in $(jq -r '.log.entries[].request.url' 538.har |grep '\.json'); do wget -P 538 $url; done
  ... or
jq -r '.log.entries[].request.url' 538.har |grep '\.json' | parallel wget -P 538 {}

https://projects.fivethirtyeight.com/2020-election-forecast/us_recirc.json

cat us_recirc.json | jq '.'

cat us_recirc.json | jq '.president'
cat us_recirc.json | jq '.president[0]'

cat us_recirc.json |jq '.president[0].candidates[0].candidate = "Joe"'
diff us_recirc.json <(cat us_recirc.json |jq '.president[0].candidates[0].candidate = "Joe"')

cat us_recirc.json | jq '.president[0].candidates[0].winprob'
cat us_recirc.json | jq '.president[0].candidates[]|select(.candidate == "Biden")|.winprob'

cat us_recirc.json | jq keys

cat us_recirc.json | jq '.president[0].candidates[0].winprob -= 5'
cat us_recirc.json | jq '.president[0].candidates[].winprob -= 5|.president[0].candidates += [{candidate: "Perot", winProb: 10}]'

cat us_recirc.json | jq '.senate[0].candidates
cat us_recirc.json | jq '.senate[0].candidates | map({(.candidate): .winprob})'
cat us_recirc.json | jq '.senate[0].candidates | map({(.candidate): .winprob}) | add'
cat us_recirc.json | jq '.senate | map({(.type): .candidates | map({(.candidate): .winprob}) | add})'
cat us_recirc.json | jq '.senate | map({(.type): .candidates | map({(.candidate): .winprob}) | add}) | add'
cat us_recirc.json | jq '.[] |= (map({(.type): .candidates | map({(.candidate): .winprob}) | add}) | add)'

cat config
cat config|jq 'walk(if type == "object" and has("password") then .password = "x" * (.password|length) else . end)'

# aws lambda list-functions | jq '.Functions |= map({Runtime, CodeSize, MemorySize})' > functions.json

cat functions.json|jq '.Functions|group_by(.Runtime)|.[]|{Runtime: .[0].Runtime, Count: length, CodeSize: (map(.CodeSize)|add/length)}'
cat functions.json|jq 'def average(f): map(f)|add/length; .Functions|group_by(.Runtime)|.[]|{Runtime: .[0].Runtime, CodeSize: average(.CodeSize), MemorySize: average(.MemorySize)}'

#JQ references:
# https://stedolan.github.io/jq/manual/
# https://stedolan.github.io/jq/tutorial/
# https://www.baeldung.com/linux/jq-command-json
# https://lzone.de/cheat-sheet/jq
# https://programminghistorian.org/en/lessons/json-and-jq
# https://remysharp.com/drafts/jq-recipes
# Jq cheat sheet