TSV String, Calc Changes in Two Numeric Columns

// GraalJS Script (engine type: 2)

//////// START "main()" /////////////////////////////////////////////////////////////////
main();
function main(){ 

//// == Config Retrieving / 工程コンフィグの参照 ==
const strTsv       = configs.get( "StrConfA1" );          /// REQUIRED //////////////
  if( strTsv     === "" ){
    throw new Error( "\n AutomatedTask ConfigError:" +
                     " Config {A1: Tsv} is empty \n" );
  }
  const arr2dTsv   = parseAsRectangular( strTsv );
const strBaseId    = configs.get( "StrConfB1" );          /// REQUIRED //////////////
  if( strBaseId  === "" ){
    throw new Error( "\n AutomatedTask ConfigError:" +
                     " Config {B1: BaseId} is empty \n" );
  }
  const numBaseId  = parseInt( strBaseId, 10 );
  if( isNaN( numBaseId ) || numBaseId < 0 ){
    throw new Error( "\n AutomatedTask ConfigError:" +
                     " Config {B1: BaseId} must be a positive integer \n" );
  }
  if( numBaseId   >= arr2dTsv[0].length ){
    throw new Error( "\n AutomatedTask ConfigError:" +
                     " Config {B1: BaseId} is larger than TsvWidth \n" );
  }
const strTargetId    = configs.get( "StrConfB2" );          /// REQUIRED //////////////
  if( strTargetId  === "" ){
    throw new Error( "\n AutomatedTask ConfigError:" +
                     " Config {B2: TargetId} is empty \n" );
  }
  const numTargetId  = parseInt( strTargetId, 10 );
  if( isNaN( numTargetId ) || numTargetId < 0 ){
    throw new Error( "\n AutomatedTask ConfigError:" +
                     " Config {B2: TargetId} must be a positive integer \n" );
  }
  if( numTargetId   >= arr2dTsv[0].length ){
    throw new Error( "\n AutomatedTask ConfigError:" +
                     " Config {B2: TargetId} is larger than TsvWidth \n" );
  }
const strPocketOutput  = configs.getObject( "SelectConfC1" ); /// REQUIRED //////////////


//// == Data Retrieving / ワークフローデータの参照 ==
// (Nothing. Retrieved via Expression Language in Config Retrieving)


//// == Calculating / 演算 ==

// compare Target field with Base field
let strOutput = "";
for( let i = 0; i < arr2dTsv.length; i++ ){
  let numTarget = parseFloat( arr2dTsv[i][numTargetId].replace(/,/g, '') );
  if( isNaN(numTarget) ){ numTarget = 0; }
  let numBase   = parseFloat( arr2dTsv[i][numBaseId].replace(/,/g, '')   );
  if( isNaN(numBase) ){ numBase = 0; }

  let numDiff = numTarget - numBase;
  let strRate = (numTarget / numBase).toFixed(3);
  strOutput  += arr2dTsv[i].join("\t") + "\t";
  strOutput  += numDiff + "\t";
  strOutput  += strRate;
  strOutput += "\n";
}
strOutput = strOutput.slice( 0, -1 ); // delete last "\n"


//// == Data Updating / ワークフローデータへの代入 ==
engine.setData( strPocketOutput, strOutput );


} //////// END "main()" /////////////////////////////////////////////////////////////////


// Parses TSV string as two-dimensional rectangular data matrix and creates a 2D array.
function parseAsRectangular( strTsv ){
  const arrTsv = strTsv.split("\n");

  /// Get numMinWidth and numMaxWidth (blank lines are excluded)
  let numMinWidth   = Infinity; // cf. String-Type Max: 1 million
  let numMaxWidth   = 0;
  let numBlanklines = 0;
  for( let i = 0; i < arrTsv.length; i++ ){
    if( arrTsv[i] === "" ){ // Skip blank lines
      numBlanklines += 1;
      continue;
    }
    let arrCells = arrTsv[i].split("\t");
    if( numMinWidth > arrCells.length ){ numMinWidth = arrCells.length; }
    if( numMaxWidth < arrCells.length ){ numMaxWidth = arrCells.length; }
  }
  engine.log( " AutomatedTask TsvDataCheck:" + 
              " MinWidth:" + numMinWidth +
              " MaxWidth:" + numMaxWidth +
              " Lines:" + arrTsv.length +
              " (BlankLines:" + numBlanklines + ")" );

  /// Get numMinWidth and numMaxWidth (blank lines are excluded)
  let arr2dTsv      = [];
  for( let i = 0; i < arrTsv.length; i++ ){
    if( arrTsv[i] === "" ){ // Skip blank lines
      continue;
    }
    let arrTmp = [];
    let arrCells = arrTsv[i].split("\t");
    for( let j = 0; j < numMaxWidth; j++ ){
      if( j < arrCells.length ){
        arrTmp[j] = arrCells[j];
      }else{
        arrTmp[j] = "";
      }
    }
    arr2dTsv.push( arrTmp );
  }

  return arr2dTsv;
}

/*
Notes:
- When the process reaches this automated task, TSV is automatically read.
    - TSV: Monthly sales total, monthly access total, etc.
- TSV (Tab Separated Values) text assumes rectangular data.
    - Data that is not rectangular is automatically formatted with empty characters.
    - Blank lines (including the end) are ignored.
- Two columns will be added on the right. (Difference / Rate)
    - Diff: {B2: Target field} - {B1: Base field}
    - Rate: {B2: Target field} / {B1: Base field}
        - The number of digits to appear after the decimal point is 3.
- Set the fields with the column ID (starting with zero).
    - String that cannot be parsed by JavaScript `parseFloat()` are considered zero.
- To delete unnecessary column, place "TSV String, Convert" etc. downstream of the workflow.
    - https://support.questetra.com/addons/tsv-string-convert-2021/

APPENDIX:
- If there is a blank line in the input TSV text, it will be skipped.
    - The line feed code for the last line is not added either.
- The number of cells in output TSV (combined TSV) is uniform for each row.
    - If the number of cells in TsvA is not uniform in each row, blank strings will be added.
- Division by zero is output as `Infinity` or `NaN`.


Notes-ja:
- 案件が自動処理工程に到達した際、文字列型データに保存されているTSVが自動的に読み込まれます。
    - TSV: 月次売上集計、月次アクセス集計、など
- TSV（Tab Separated Values）テキストは、矩形データを前提とします。
    - 矩形でないデータは、空文字によって自動整形されます。
    - 空行（末尾改行を含む）は無視されます。
- 最も右側に２列が追加されます。（差分・変化率）
    - 差分： {B2:計測値フィールド} - {B1:基準値フィールド}
    - 変化率： {B2:計測値フィールド} / {B1:基準値フィールド}
        - 小数点以下の表示桁数は3桁です。
- フィールド列は、列ID（ゼロ始まり）で設定してください。
    - JavaScript `parseFloat()` で解析できない文字列はゼロと見なされます。
- 不要なデータ列は『TSV 文字列, 変換』等をワークフロー下流に配置して削除します。
    - https://support.questetra.com/ja/addons/tsv-string-convert-2021/

APPENDIX-ja:
- 入力TSVテキストに空行がある場合、スキップされます。
    - 最終行の改行コードも付与されません。
- 出力されるTSV（結合されたTSV）のセル数は各行で均一となります。
    - TsvAのセル数が各行で均一でなかった場合、空文字が追加されます。
- 0 の除算は `Infinity` や `NaN` と出力されます。
*/