Bhūpajñādivākyas: A quick tool to extract the longitude of the Sun

There are different categories of Indian astronomical texts ranging from theoretically complex ones to simple practical manuals. The texts pertaining to vākya system are the ones which provide simplified algorithms to compute different astronomical quantities using vākyas. Vākyas (or mnemonics) are simple phrases/sentences in which numerical values—associated with an astronomical parameter–are encoded. Since these are meaningful phrases, it is very easy to memorize them and reproduce the numerical values quickly–without any errors. In this paper, by taking an example of Bhūpajñādi-vākyas, we shall demonstrate that the system is very efficient in terms of practical utility without compromising the accuracy.