IMLOG2 Function (Calligra Sheets)

• Introduced: First release not established; the name is present in Calligra 2.4.0 source.
• Supported in: Calligra Sheets 26.08.2, with no retirement established.
• Scope: Desktop Sheets with the Engineering module. Examples use English semicolon-separated formulas.
• Checked: October 14, 2026. Formulas were executed through the official 25.04.2 engine library and checked against source and independent mathematics. This is not GUI-cell or workbook-import evidence; 26.08.2 was source-checked, not executed.

IMLOG2 evaluates the principal natural complex logarithm and divides it by LN(2). Its real component describes a base-two magnitude scale; its imaginary component is the principal phase divided by LN(2). It is not a binary-string converter. Function help.

=IMLOG2(complexValue)

Exactly one argument is required. Inputs can be numeric or complex-convertible values. Use COMPLEX for explicit numeric components; the mathematical finite logarithm requires nonzero magnitude. Registration and implementation, with versioned help.

Results are shown as (real,imaginary) component pairs, rounded to twelve decimal places, not a literal cell format. A component rounded to zero is shown as 0; the stored value may still contain a tiny residual or signed zero. NaN means not-a-number; infinity and NaN are not finite results.

For 3+4i, =IMLOG2(COMPLEX(3;4)) gives approximately 2.321928094887+1.337804212451i. The magnitude is 5, so the real component is LOG2(5). The imaginary component is atan2(4,3)/LN(2), not the unscaled angle.

On the positive real axis, powers of two have familiar real logarithms. A negative real input is not on that same branch: it has a nonzero principal phase and therefore a nonzero imaginary logarithm. Do not silently discard that component in a model.

The executed =IMLOG2(COMPLEX(-8;0)) returned approximately 3+4.532360141827i. The real component corresponds to magnitude 8, and the imaginary component is π/LN(2). The retained real component is slightly above 3 at the last stored digits, so the displayed integer is a rounded numerical result.

The implementation explicitly divides the complex natural logarithm by a constant converted through double precision. These examples do not establish arbitrary-precision base conversion. Branch adjustments scale too: a full turn corresponds to 2πi/LN(2), so product-log identities require the same care as with IMLN.

Zero exposed (−Infinity,0) in the tested engine without its error flag being set. Invalid text “abc” and an empty string became zero and produced the same result. None is a finite logarithm, and this engine-only evidence does not establish the GUI’s displayed cell value.

TRUE became 1 and returned zero. Zero or two arguments produced #VALUE!. Validate source text and input magnitude before using the result. This function does not decode quoted binary digits such as “1010” as base-two integers.

The complex conversion helper explains the text and Boolean cases above. The inspected Engineering module and complex converter are byte-identical between 25.04.2 and 26.08.2. That source comparison does not establish every locale, import path or extreme-value case.

Use COMPLEX to construct values from numeric components, IMABS for magnitude, and IMARGUMENT for principal phase.