Slow performance of max and min methods of Series

[rxmvinv]

Hello thank you for grate framework.

Please help me to resolve the issue with Series' methods min and max

Sequence of DataFrame is taken on iteration inside select method on it then it's converted to Series and everything works fine and fast before calling min and max methods on Series.

What is the best solution to this issue?

Code is below:

const data_forge_1 = require("data-forge");

function f () {
  return this.select((df, i) => {

      const takeSequence = this.skip(i).take(50);//.bake();

      const ls = takeSequence.getSeries('l');//.bake();

      const hs = takeSequence.getSeries('h');//.bake();

      // with calls to min and max it's starting to work really slowly without calls it's a few seconds
      const min_val = ls.min();
      const max_val = hs.max();

      return {min_val, max_val};

  }).bake()
}

data_forge_1.DataFrame.prototype.f = f;

How it's applied:

const dataForge = require('data-forge');
require('data-forge-fs')

let inputSeries = dataForge.readFileSync("path/to/file.csv") // thousands entities
    .parseCSV()

const f = inputSeries.f();

inputSeries = inputSeries
    .withSeries("f", f);

[ashleydavis]

Hi @rxmvinv thanks for reporting the issue. Do you have data that demonstrates the problem? If could submit a csv file in Gist that would be awesome.