in src/axisHelper.ts [383:390]
export function isLogScalePossible(domain: any[], axisType?: ValueType): boolean {
if (domain == null || domain.length < 2 || isDateTime(axisType)) {
return false;
}
return (domain[0] > 0 && domain[1] > 0)
|| (domain[0] < 0 && domain[1] < 0); // doman must exclude 0
}