There seem to be two main cara kāraka schemes in use in the world today:
- a scheme with 8 kārakas;
- a scheme with 7 kārakas with pitṛ kāraka excluded.
Option (1) is described in the following work:
- “Jaimini Maharishi’s Upadesa Sutras”, verses 1.1.10-19 by Sanjay Rath (1997)
The description of this option can also be found in Bṛhat Pārāśara Horā Śāstra, chapter 32.
Option (2) is described in the following sources (note that the same classical text is used, but a different variation of it and a different conclusion is reached):
- “Jaimini Astrology - My 7 Step Approach” by K. N. Rao
- “Studies in Jaimini Astrology”, chapter 2 by B. V. Raman (1986)
- “Jaimini Sutramritam”, verses 1.1.11-19 by Iranganti Rangacharya (1995)
- “Jaimini Sutras”, verses 1.1.11-19 by B. Suryanarain Rao (1955)
Chakra Darshana implements both mainstream options to satisfy the needs of both schools.
However, there also exist other methods (not included in Chakra Darshana) for calculating cara kārakas. One of them is based on Bṛhat Pārāśara Horā Śāstra, chapter 32, and suggests a 7 kāraka scheme, where mātṛ and putra kārakas are considered to be the same (this is mentioned in verses 32.13-17).
Another method is described in a research “Parasara’s Teachings on Chara Karakas” article by P. V. R. Narasimha Rao. While the two main options always use either 8 or 7 kārakas, the linked article is an attempt to understand the instructions given in Bṛhat Pārāśara Horā Śāstra on using either 8 or 7 kārakas depending on whether two or more grahas have identical degrees.
Please note that at this point Chakra Darshana does not attempt to deal with that situation of identical degrees. One of the reasons is that different authors describe different ways of how this situation should be resolved. For instance, the translation of Bṛhat Pārāśara Horā Śāstra by R. Santhanam (1984) seems to imply that, when two grahas are tied for a particular position, there will be a shortage of dara kāraka (the last kāraka). Translation of the same text by Girish Chand Sharma (1999) seems to suggest that, when two grahas are tied for a position, say bhrātṛ kāraka, then both become the significators for bhrātṛ kāraka and the significator for the following mātṛ kāraka should be taken from sthira kārakas. The article by P. V. R. Narasimha Rao seems to reverse that logic and assign a significator (only one) to mātṛ kāraka instead, leaving bhrāṭr kāraka to be judged from sthira kāraka.
There are also other opinions on whether minutes and seconds should be used for ātmā kāraka only or whether Rāhu can be an ātmā kāraka. Since there are so many variations, Chakra Darshana limits itself to the two mainstream options described above. If some other method is desired, the calculation should be performed by an astrologer manually.