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Engineering function
BESSELI
Returns the modified Bessel function In(x).
Rarely usedDifficulty 1600 · ExpertUsage rank #511 of 520
When to use it
The modified Bessel function of the first kind, In(x).
The shape of it
- Syntax
=BESSELI(x, n)
Worked examples
Order one
=BESSELI(1.5,1) → 0.981666428
Order 1 at 1.5.
At zero
=BESSELI(0,0) → 1
I0 at zero is 1.
Order zero
=BESSELI(1,0) → 1.266065878
Order 0 at 1.
Worth knowing
- Grows exponentially with x.
- Appears in heat conduction and Rician noise models.
- Order is truncated to an integer.
Where it goes wrong
- #NUM! for a negative order.
- #VALUE! for non-numeric input.
Related
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