in_max and in_min could be equal and thus return NaN

@randomor it can be easily fixed by

  const diff = (in_max - in_min) || 1; 
  return ((x - in_min) * (out_max - out_min)) / diff + out_min;

Not for self-promotion, if you want to use heat-map solely for this repo, probably you can test out my fork, I recently go through the heatmap code and the core abstract-chart.js. Found a lot of hardcode number and some shared style abusing #345 . And it becomes a pain to use.

So I basically reenginner many of them and modify position calculation to make the calculation straight and intuitive. <BarChart> and <ContributionGraph> are now fully dynamic and responsive. ReadMe.md was updated as well for those changes. <LineChart> and <StackedBar> are surely broken under my fork.

I probably PR my fork to main as a proposal or suggestion even I fixed all of them, since it will likely break the original use, depending on how heavily the issue properties are abused.

indiespirit / react-native-chart-kit

in_max and in_min could be equal and thus return NaN #349