Contact

IMLOG2 in Collabora Office: Track Binary Scaling of Complex Quantities

Engineering Intermediate Collabora Office Calc

Use Collabora complex base-two logarithms to track doubling, separate direction from magnitude and reconstruct complete values with explicit base conversion.

Verification status: See the evidence and test scope described in this guide. How formula examples are checked

Quick answer: IMLOG2 returns a complex logarithm to base two. The official =IMLOG2("1+j") example is approximately 0.50+1.13j. Multiplying a first-quadrant input by two adds one to the real logarithm coefficient.

Availability and version history

  • Introduced: the original Collabora release and launch date are not established by the reviewed sources.
  • Availability: documented in Collabora Office 26.04 desktop help.
  • Platform scope: online and mobile deployment support is not inferred from the desktop documentation.
  • Checked: October 14, 2026. Function-specific documentation and independent controls; no native Collabora execution.

Syntax and the meaning of binary logarithm

=IMLOG2("ComplexNumber")

The dedicated Collabora section accepts the documented x+yi or x+yj complex form and identifies a binary logarithm. This is a logarithm with base two, not a conversion of a decimal quantity into a string of zero and one digits.

For the first-quadrant inputs here, the independent formula is the natural complex logarithm divided by ln(2). Its real coefficient measures log2 of the magnitude; its imaginary coefficient is the first-quadrant angle divided by ln(2).

The source does not establish a global argument interval or negative-axis branch convention. The examples retain positive real and imaginary coefficients.

Example 1: follow successive doublings

Format A2:A5 as Text and enter 1+j, 2+2j, 4+4j and 8+8j. Put =IMLOG2(A2) in B2 and extract real and imaginary coefficients in C2:D2 with IMREAL and IMAGINARY. Fill down.

A, input C, real coefficient D, imaginary coefficient
1+j 0.5 1.133090035
2+2j 1.5 1.133090035
4+4j 2.5 1.133090035
8+8j 3.5 1.133090035

The input magnitudes are sqrt(2), twice sqrt(2), four times sqrt(2) and eight times sqrt(2). Since sqrt(2)=2^0.5, the real coefficients increase from 0.5 in steps of one.

The imaginary value is pi/(4×ln(2)), shown to nine decimals. It stays constant because all four inputs point in the same first-quadrant direction.

Example 2: inspect a different direction

For =IMLOG2("3+4j"), the independently expected coefficients are 2.321928095 and 1.337804212. For 4+3j, they are 2.321928095 and 0.928375858.

Both inputs have magnitude five, so log2(5) appears in both real parts. Their imaginary parts distinguish their directions. A scalar log2 magnitude therefore cannot substitute for the complete complex result.

=LOG(IMABS("3+4j");2) supplies the real magnitude summary explicitly. The base argument of LOG is two; the imaginary coefficient remains information that this real formula does not return.

Advanced example: expose both base-change coefficients

For each primary input, compare the IMLOG2 output with:

=IMDIV(IMLN(A2);COMPLEX(LN(2);0;"j"))

This has the same expected coefficients as the table. The real complex divisor is constructed explicitly, so no undocumented acceptance of a plain numeric argument by IMDIV is needed.

For 1+j, the natural-log real part ln(2)/2 becomes exactly 0.5 in the mathematical model. The angle pi/4 becomes approximately 1.133090035 after division by ln(2). It has changed units as a logarithm coefficient; interpreting it directly as the original angle would be wrong.

IMLN supplies the natural complex logarithm, and IMDIV divides the complete quantity.

Advanced example: check scaling differences and reconstruction

Put =IMSUB(B3;B2) in F2, =IMSUB(B4;B3) in F3 and =IMSUB(B5;B4) in F4. Each independently expected difference has real coefficient one and imaginary coefficient zero.

The total difference between the last and first logarithms is three, representing three doublings. The corresponding positive-real scale factor is 2^3=8; this agrees with the original coefficient change from 1 to 8.

To reconstruct an original quantity from B2, use:

=IMEXP(IMPRODUCT(B2;COMPLEX(LN(2);0;"j")))

Filled down, the expected quantities are 1+j, 2+2j, 4+4j and 8+8j. Use both IMREAL and IMAGINARY comparisons against the original values, with a stated tolerance such as 1e-9 for this fixture. Keep unrounded formulas rather than retyping the displayed coefficients.

Boundaries and interpretation

Zero has no finite logarithm, but the reviewed source does not establish its native error code. Negative-axis representatives, malformed complex text, mixed suffixes and numerical overflow or underflow are also not certified here.

Do not confuse a change of one in this logarithm with adding one to the original complex number. It corresponds to multiplying the entire quantity by two in the positive-real scaling examples. General complex product identities require branch awareness; these controlled doublings do not establish an unrestricted identity across every quadrant.

References and verification

Complete dedicated function section reviewed. Results are independently calculated mathematical controls or explicit published examples, not captured native application results. Formulas use English names and semicolon separators.