ironpairs

README.md

0. Open a terminal and paste the following command ☝️😲WITHOUT EXECUTING IT:
   
   

   pbpaste | npx https://gist.github.com/abernier/00ac26ff978aebdfa6f3f65019fe2bf0 10 | pbcopy

   
   NB: 10 being the number of combinations wanted
   
1. In a spreadsheet, copy rows of names:
   
2. In the previous terminal, press now ENTER to execute the pasted command at step 0.:
   
3. Paste the result into spreadsheet
   

index.js

#!/usr/bin/env node

// Run
// ---
// $ npm install roundrobin
// $ pbpaste | node pairs.js 25 | pbcopy

const roundrobin = require('roundrobin')

const numberOfRounds = Number(process.argv[2])
let names = process.argv.slice(3)


if (names.length > 0) {
  assignPairs(names)
} else {
  let nameString = ''

  process.stdin.setEncoding('utf8')
  process.stdin.on('data', chunk => nameString += chunk)
  process.stdin.on('end', () => {
      names = nameString.split('\n')
      assignPairs(names)
  })
}


function assignPairs (namesArray) {
  // Add an extra name for odd numbered groups.
  // Otherwise roundrobin leaves out the extra name in each round.
  if (namesArray.length % 2 === 1) {
    namesArray.push('Imaginary Pair')
  }

  let pairs = []

  // Create several sets of pairs to fill all pairing days needed.
  // We will get some extras but they can be useful.
  while (pairs.length < numberOfRounds) {
    const newPairs = roundrobin(namesArray.length, namesArray)

    pairs = pairs.concat(newPairs)
  }


  // If odd numbered group, assign trios in each round.
  if (namesArray.indexOf('Imaginary Pair') > -1) {
    const trioCount = {}
    const triodPairs = []

    namesArray.forEach(name => trioCount[name] = 0)

    pairs.forEach(round => {
      let extraName

      // Get rid of the 'Imaginary Pair' pairing
      const roundWithTrio = round
        .filter(pair => {
          const extraIndex = pair.indexOf('Imaginary Pair')

          // Keep extra name that was paired with 'Imaginary Pair' this round
          if (extraIndex > -1) {
            const nameIndex = (extraIndex + 1) % 2
            extraName = pair[nameIndex]
          }

          return extraIndex === -1
        })
        .sort((pairA, pairB) => {
          const trioCountA = trioCount[pairA[0]] + trioCount[pairA[1]]
          const trioCountB = trioCount[pairB[0]] + trioCount[pairB[1]]
          return trioCountA - trioCountB
        })

      let currentTrio = roundWithTrio[0]
      currentTrio.push(extraName)
      currentTrio.forEach(name => trioCount[name] += 1)

      // Save new round
      triodPairs.push(roundWithTrio)
    })

    pairs = triodPairs
  }


  // Display results for pasting onto spreadsheet.
  let row = ''

  pairs.forEach(function (round) {
    row += '"'

    round.forEach(function (pairing) {
      row += `${pairing[0]} with ${pairing[1]}`
      if (pairing.length > 2) {
        row += ` and ${pairing[2]}`
      }
      row += '\n'
    })

    row += '"\t'
  })

  console.log(row)
}

package.json

{"name": "ironpairs", "version": "0.1.0", "bin": "./index.js", "dependencies": {"roundrobin": "1.0.3"}}