in src/radarChart.ts [1195:1206]
public static countMinValueForDisplaySettings(minValue: any, settings: RadarChartSettings) {
if (minValue < 0) { // for negative values
settings.displaySettings.minValue = minValue;
} else {
if (settings.displaySettings.minValue > minValue) {
settings.displaySettings.minValue = minValue;
}
if (settings.displaySettings.minValue < 0) {
settings.displaySettings.minValue = 0;
}
}
}