Katapayadi system

• The consonant, ḷ (Malayālam: ള, Devanāgarī: ळ) is employed in works using the Kaṭapayādi system, like Mādhava's sine table.
• Some practitioners do not map the stand-alone vowels to zero. But, it is sometimes considered valueless.

• Mādhava's sine table constructed by 14th century Kerala mathematician-astronomer Mādhava of Saṅgama·grāma employs the Kaṭapayādi system to enlist the trigonometric sines of angles.
• Karaṇa·paddhati, written in the 15th century, has the following śloka for the value of pi (π)

അനൂനനൂന്നാനനനുന്നനിത്യൈ-

സ്സമാഹതാശ്ചക്രകലാവിഭക്താഃ

ചണ്ഡാംശുചന്ദ്രാധമകുംഭിപാലൈര്‍-

വ്യാസസ്തദര്‍ദ്ധം ത്രിഭമൗര്‍വിക സ്യാത്‌

Transliteration

anūnanūnnānananunnanityai

ssmāhatāścakra kalāvibhaktoḥ

caṇḍāṃśucandrādhamakuṃbhipālair

vyāsastadarddhaṃ tribhamaurvika syāt

It gives the circumference of a circle of diameter, anūnanūnnānananunnanityai (10,000,000,000) as caṇḍāṃśucandrādhamakuṃbhipālair (31415926536).

• Śaṅkara·varman's Sad·ratna·mālā uses the Kaṭapayādi system. A famous verse found in Sad·ratna·mālā is

भद्राम्बुद्धिसिद्धजन्मगणितश्रद्धा स्म यद् भूपगी:

Transliteration

bhadrāṃbuddhisiddhajanmagaṇitaśraddhā sma yad bhūpagīḥ

Splitting the consonants gives,

Reversing the digits to modern-day usage of descending order of decimal places, we get 314159265358979324 which is the value of pi (π) to 17 decimal places, except the last digit might be rounded off to 4.

• This verse encrypts the value of pi (π) up to 31 decimal places.

 गोपीभाग्यमधुव्रात-श्रुग्ङिशोदधिसन्धिग॥
 खलजीवितखाताव गलहालारसंधर॥

 ಗೋಪೀಭಾಗ್ಯಮಧುವ್ರಾತ-ಶೃಂಗಿಶೋದಧಿಸಂಧಿಗ ||
 ಖಲಜೀವಿತಖಾತಾವ ಗಲಹಾಲಾರಸಂಧರ ||

This verse directly yields the decimal equivalent of pi divided by 10: pi/10 = 0.31415926535897932384626433832792

 గోపీభాగ్యమధువ్రాత-శృంగిశోదధిసంధిగ |
 ఖలజీవితఖాతావ గలహాలారసంధర ||

Melakarta chart as per Kaṭapayādi system

• The melakarta ragas of the Carnatic music is named so that the first two syllables of the name will give its number. This system is sometimes called the Ka-ta-pa-ya-di sankhya. The Swaras 'Sa' and 'Pa' are fixed, and here is how to get the other swaras from the melakarta number.

1. Melakartas 1 through 36 have Ma1 and those from 37 through 72 have Ma2.
2. The other notes are derived by noting the (integral part of the) quotient and remainder when one less than the melakarta number is divided by 6. If the melakarta number is greater than 36, subtract 36 from the melakarta number before performing this step.
3. 'Ri' and 'Ga' positions: the raga will have:
   • Ri1 and Ga1 if the quotient is 0
   • Ri1 and Ga2 if the quotient is 1
   • Ri1 and Ga3 if the quotient is 2
   • Ri2 and Ga2 if the quotient is 3
   • Ri2 and Ga3 if the quotient is 4
   • Ri3 and Ga3 if the quotient is 5
4. 'Da' and 'Ni' positions: the raga will have:
   • Da1 and Ni1 if remainder is 0
   • Da1 and Ni2 if remainder is 1
   • Da1 and Ni3 if remainder is 2
   • Da2 and Ni2 if remainder is 3
   • Da2 and Ni3 if remainder is 4
   • Da3 and Ni3 if remainder is 5

• See swaras in Carnatic music for details on above notation.

The katapayadi scheme associates dha${\displaystyle \leftrightarrow }$9 and ra${\displaystyle \leftrightarrow }$2, hence the raga's melakarta number is 29 (92 reversed). Now 29 ${\displaystyle \leq }$ 36, hence Dheerasankarabharanam has Ma1. Divide 28 (1 less than 29) by 6, the quotient is 4 and the remainder 4. Therefore, this raga has Ri2, Ga3 (quotient is 4) and Da2, Ni3 (remainder is 4). Therefore, this raga's scale is Sa Ri2 Ga3 Ma1 Pa Da2 Ni3 SA.

From the coding scheme Ma ${\displaystyle \leftrightarrow }$ 5, Cha ${\displaystyle \leftrightarrow }$ 6. Hence the raga's melakarta number is 65 (56 reversed). 65 is greater than 36. So MechaKalyani has Ma2. Since the raga's number is greater than 36 subtract 36 from it. 65–36=29. 28 (1 less than 29) divided by 6: quotient=4, remainder=4. Ri2 Ga3 occurs. Da2 Ni3 occurs. So MechaKalyani has the notes Sa Ri2 Ga3 Ma2 Pa Da2 Ni3 SA.

As per the above calculation, we should get Sa ${\displaystyle \leftrightarrow }$ 7, Ha ${\displaystyle \leftrightarrow }$ 8 giving the number 87 instead of 57 for Simhendramadhyamam. This should be ideally Sa ${\displaystyle \leftrightarrow }$ 7, Ma ${\displaystyle \leftrightarrow }$ 5 giving the number 57. So it is believed that the name should be written as Sihmendramadhyamam (as in the case of Brahmana in Sanskrit).

Important dates were remembered by converting them using Kaṭapayādi system. These dates are generally represented as number of days since the start of Kali Yuga. It is sometimes called kalidina sankhya.

• The Malayalam calendar known as kollavarsham (Malayalam: കൊല്ലവര്‍ഷം) was adopted in Kerala beginning from 825 CE, revamping some calendars. This date is remembered as āchārya vāgbhadā, converted using Kaṭapayādi into 1434160 days since the start of Kali Yuga.[11]
• Narayaniyam, written by Melpathur Narayana Bhattathiri, ends with the line, āyurārogyasaukhyam (ആയുരാരോഗ്യസൌഖ്യം) which means long-life, health and happiness.[12]

This number is the time at which the work was completed represented as number of days since the start of Kali Yuga as per the Malayalam calendar.

• Some people use the Kaṭapayādi system in naming newborns.[13][14]
• The following verse compiled in Malayalam by Koduṅṅallur Kuññikkuṭṭan Taṃpurān using Kaṭapayādi is the number of days in the months of Gregorian Calendar.

പലഹാരേ പാലു നല്ലൂ, പുലര്‍ന്നാലോ കലക്കിലാം

ഇല്ലാ പാലെന്നു ഗോപാലന്‍ – ആംഗ്ലമാസദിനം ക്രമാല്‍

Transiliteration

palahāre pālu nallū, pularnnālo kalakkilāṃ

illā pālennu gopālan – āṃgḷamāsadinaṃ kramāl

Translation: Milk is best for breakfast, when it is morning, it should be stirred. But Gopālan says there is no milk – the number of days of English months in order.

Converting pairs of letters using Kaṭapayādi yields – pala (പല) is 31, hāre (ഹാരേ) is 28, pālu പാലു = 31, nallū (നല്ലൂ) is 30, pular (പുലര്‍) is 31, nnālo (ന്നാലോ) is 30, kala (കല) is 31, kkilāṃ (ക്കിലാം) is 31, illā (ഇല്ലാ) is 30, pāle (പാലെ) is 31, nnu go (ന്നു ഗോ) is 30, pālan (പാലന്‍) is 31.