Mela 46Vasu chakraM2
Shadvidamargini
also known as Shadvidhamargini
The name is the number
Shadvidamargini
Shadssa6viva464 reversed46
The 'Sh' here is retroflex ṣa = 6 (as in shad-, 'six'). 'Shad-vi' — the d closes the first syllable, so the second syllable counts va = 4.
Every mela name encodes its own number — how the katapayadi sutra works.
SSR1R1G2G2M2M2PPD2D2N2N2SS (upper octave)
SS (upper octave)N2N2D2D2PPM2M2G2G2R1R1SS
How to know it
An uncommon scale with a searching quality — the prati madhyama pulls upward while suddha rishabha keeps tugging the line back down.