Formualizer Docs
ReferenceFunctionsEngineering Functions

BESSELI

BESSELI: Returns the modified Bessel function In(x).

Summary

Computes the modified Bessel function of the first kind for a real value x and a non-negative integer order n. The order is truncated toward zero, matching spreadsheet behavior.

Remarks

  • Arguments are supplied as BESSELI(x, n).
  • n must truncate to a non-negative integer order.
  • Invalid domains or non-finite results return #NUM!.

Examples

First-order modified Bessel I
Grid
CellValue
No inputs on Sheet1.
Formula
=
Result
Not evaluated yet.
Expected
0.2578943053908963
Order is truncated
Grid
CellValue
No inputs on Sheet1.
Formula
=
Result
Not evaluated yet.
Expected
0.2578943053908963

FAQ

What happens to fractional order values?

The order argument is truncated toward zero before evaluation.

Runtime metadata

Category

Engineering

Signature

BESSELI(arg1: Any, arg2: Any)

Arity

min 2, max 2

Arguments

arg1

Any · Scalar

arg2

Any · Scalar

Caps

PURE

Source

crates/formualizer-eval/src/builtins/engineering.rs

Engineering Functions

Generated reference pages for Engineering functions.

BESSELJ

BESSELJ: Returns the Bessel function Jn(x).

On this page

SummaryRemarksExamplesRelated functionsFAQWhat happens to fractional order values?Runtime metadata