src/charts/tooltip.js
function getValueText(data) {
            let value = data[valueLabel];
            let valueText;

            if (data.missingValue) {
                valueText = '-';
            } else {
                valueText = getFormattedValue(value).toString();
            }

            return valueText;
        }
function getValueText(data) {
            let value = data[valueLabel];
            let valueText;

            if (data.missingValue) {
                valueText = '-';
            } else {
                valueText = getFormattedValue(value).toString();
            }

            return valueText;
        }
function getValueText ( data ) { let value = data [ valueLabel ] ; let valueText ; if ( data . missingValue ) { valueText = '-' ; } else { valueText = getFormattedValue ( value ) . toString ( ) ; } return valueText ; }
Extracts the value from the data object
@param  {Object} data Data value containing the info
@return {String}      Value to show
Extracts the value from the data object