What's the name of the tree with purple flowers on top?

Lagerstroemia indica, alias: itchy flower, itchy tree, purple flower, purple orchid, mosquito flower, Myrica rubra, zinnia, skinless tree, Latin scientific name: Lagerstroemia indica L? Deciduous shrubs or small trees of Lysimachiaceae and Lagerstroemia, up to 7 meters high; Bark is smooth, gray or grayish brown; Twisted branches, slender branchlets, alternate or sometimes opposite leaves, papery, oval, oblong or obovate, green to yellow when young, purple-black when mature or dry, and ventricular dehiscence; Seeds winged, ca. The flowering period is from June to September, and the fruiting period is from September to June. Lagerstroemia indica has beautiful posture, smooth trunk and bright colors; When it blooms, it happens to be the season when there are few flowers in summer and autumn, and the flowering period is long. Therefore, it is known as "Hundred Days Red" and "Summer Blue and White Flowers Full", and it is a good bonsai for viewing flowers, stems and roots; Roots, bark, leaves and flowers can be used as medicine.