What Kathirveechi measures
Kathirveechi is the Jamakol technique of counting rays. Instead of asking only which planet sits where, it asks how much light a sign is receiving — from itself, from the planets occupying it, and from the planets aspecting it. The result is a number, and numbers can be compared across the twelve houses, which is what makes the Kathir grid useful.
Our implementation follows the planetary and sign ray tables in the supplied Umashankara U edition of Jamakkol Prasannam, pages 34 to 36, in preference to a differing provisional transcription in the course notes.
How a cell is computed
For each target sign, the engine sums:
- the sign's own rays, from the book's sign table;
- the rays of each planet occupying it;
- the rays of each planet aspecting it, using the platform's confirmed standard aspect table.
Dignity then modifies a planet's contribution:
| Condition | Effect on that planet's rays |
|---|---|
| Own sign | Doubled |
| Exaltation | Tripled |
| Debilitation | Halved |
| Retrogression | Halved |
| Kavippu contact | Halved |
Two honest notes about the source. Page 35 contains a sentence implying zero rays on debilitation, while the worked example on page 36 takes half; our engine follows the worked example, because a demonstrated calculation outranks an ambiguous sentence. And where several modifiers apply at once, the book supplies no combined example — applying them multiplicatively is our stated implementation convention, and it is exposed in the trace so you can see exactly what was multiplied.
Worked examples you can check
These are the acceptance examples our tests hold to:
- Scorpio Udhayam, with Jupiter in Scorpio and Mars in Leo → 22 rays.
- The same cast with a debilitated Moon added in Scorpio → 32.5 rays, provided Kavippu is elsewhere and the planets are direct.
They are ray measures. They are not days, not dates, and not guaranteed outcomes — a high cell says the matter is well lit, not that it is certain.
The Kathir grid
The grid extends the same calculation to all twelve houses, so you can read the distribution rather than a single figure. The Udhayam cell is the one the book's worked example computes; the other cells extend the identical method transparently.
One rule governs the display: the transit layer and the functional Jama layer are shown independently and are never added together into one unexplained score. Mixing them would produce a number with no defensible meaning, and no way for a reader to tell which layer moved it.
Kiraga Nilai and Pagai Murai alongside it
The ray grid answers "how lit is this house". Two neighbouring screens answer different questions. Kiraga Nilai gives each planet's dignity, its natural relationship to the sign lord, its house from Udhayam, retrogression and Kavippu contact — transit and Jama dignity kept as separate layers. Pagai Murai gives directed natural friendship and enmity between the seven classical planets, directed because the relation is not symmetrical in the classical tables. Read together, they say how strong a factor is, how it relates to its neighbours, and how much light its house receives.
Colour of dress
Page 37 of the same edition carries an Aarudam-based clothing indication, taught in the context of lost objects and theft. It is worth being precise about what it is: a descriptive indication in that context, not a lucky-colour prescription and not evidence identifying a person. Our screen shows matching occupants separately by layer, and returns an explicit "no occupant" result when there is none. Jupiter is blue in this table, and we do not substitute the yellow association from the general karaka table.
Where to find these screens
All of this sits on the Analysis side of a Jamakol cast: Kathir Analysis for the grid and the ray trace, Planetary Analysis for Kiraga Nilai and Pagai Murai. Because the entry screen of a cast is the only one that charges, you can move between them freely once a cast is open.
Related: the Jama ring · success rules.
Sources
Jamakkol Prasannam, Umashankara U edition, pages 34–37, supplied to us for the ray and clothing tables; the platform's confirmed standard aspect table; and our documented conventions where the text leaves a combination unspecified.