Vastu Ganitham refers to the mathematical calculations at Vastu Shastra. Vastuganitam, like Vastushastra (the science of architecture), is related to ‘vastu’, landed property. The science of architecture is Vastushastra. Construction of any building, temple, palace, house, or theater comes under this science. In Hinduism, many masters of Vastushastra are referred to, including Brahma, Tvasta, Maya, Matanga, Bhrigu,Kashyapa, Agastya, Shukra, Parasara, Nagnajit, Prahlada, Sakra, Brihaspati, and Manasara.
Vishwakarma is the supreme acharya (teacher) in the Vastushastra of the gods, and Maya is the master for the demons. Vishwakarma Prakasam of Vishwakarma and Mayamatam are considered as authentic texts on Hindu architecture. Sambu, Garga, Atri, Vasistha, Parasara, Brihadratha, Vishwakarma and Vasudeva are leading exponents of Vastushastra. Vishwakarma Shilpa is another text followed in South India, and it deals with the technical and ritualistic aspects of Vastushastra. Shaivagama, Atri Samhita, Vaikhanasa Agama, Dipta Tantra, Tantra Samuccaya, Ishava Gurudeva Paddhati Kashyapa Shilpa, Agastya, Sakalodhikara, Sanatkumara Vastushastra, Shilpa Samgraha, Shilparatna, Chitra Akshara, Manasara, Samarangana Sutradhara of Bhoja, Sutradhara Mandana, Vastu Ratnavali, Vastu Pradipika and many other texts in Sanskrit illustrate the principles of this science. But the period of these texts is not well identified.
Climatology is one of the many factors considered in Vastu Ganitham for construction. The solar radiation at a place with flux density Q is inversely proportional to the square of the distance from the sun. Another factor is wind. The earth’s rotation is essentially constant; hence the net friction exerted by the wind is negligible; but the direction of the wind is to be considered for proper ventilation which, in turn, reflects in a plan of the building.
The measures of central tendencies, such as standard deviation, estimation, numerical and graphical frequency distribution, and normal as well as chi-square distributions are the basic mathematical tools required for construction.
Tropical architecture needs the consideration of sunlight and its glare. The reflection constant of a metal determines the quantity of radiant heat. If H and V are horizontal and vertical shadow angles respectively, and h and v are corresponding shadow heights, then the results used are tan H = h and tan V = v.