import type { IGroup } from './interfaces' ; export function isMissingValue ( v ) { if ( v == null || v === undefined || v === '' || v === 'NA' || v === 'na' || v === 'Na' || v === 'nA' || v === 'NaN' || ( typeof v === 'number' && Number . isNaN ( v ) ) ) { return true ; } if ( ! Array . isArray ( v ) ) { return false ; } for ( const vi of v ) { if ( ! isMissingValue ( vi ) ) { return false ; } } return true ; } export function isUnknown ( v ? ) { return v == null || v === undefined || Number . isNaN ( v ) ; } export const FIRST_IS_NAN = - 1 ; export const FIRST_IS_MISSING = 1 ; export const missingGroup = { name : 'Missing values' , color : 'gray' , } ;