index.js

export const mapActivities = (activities, state) => {
  if (
    !isArray(activities) ||
    !activities.length ||
    !isArray(state.experiments.list) ||
    !state.experiments.list.length
  )
    return { bySignature: {}, byExperiment: [] };

  // get all activities in signature, and min/max
  const values = activities.map((activity) => activity.value);
  const min = arrayMin(values); // Math.min(...values);
  const max = arrayMax(values); // Math.max(...values);
  const bySignature = { values, min, max };

  // bring sample info out of activities and into map
  const activityMap = {};
  const scoreMap = {};
  for (const { sample, value } of activities) activityMap[sample] = value;
  for (const { sample, score } of activities) scoreMap[sample] = score;

  // get activities by experiment
  const byExperiment = state.experiments.list
    .map((experiment) => {
      // get experiment samples info
      const samples = experiment.samples;
      // get activity value of each sample
      const values = samples
        .map((sample) => activityMap[sample])
        .filter((value) => value);
      const score = samples
        .map((sample) => scoreMap[sample])
        .filter( <IDK HOW TO GET THE FIRST THING IN A LIST IN JAVASCRIPT BUT I WOULD DO IT HERE>)
      // return all needed info
      return {
        id: experiment.id,
        accession: experiment.accession,
        values,
        count: values.length,
        score,
        samples
      };
    })
    .filter((experiment) => experiment.count);