See? Here's a graph of your productivity gains after using spark: ▁▂▃▅▇

This is a Crystal port of the python spark.

Just pass to the Spark.string function an array of numbers.

Spark.string([0,30,55,80,33,150])
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the function accept a second parameter for normalize data and fit min:

Spark.string([0, 30, 55, 80, 33, 150], true)
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