LOGINV 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 Statistical module. Examples use English semicolon-separated formulas.
• Checked: October 14, 2026. Selected formulas ran through the official 25.04.2 engine library. Source and independent mathematics were checked. This is engine evidence, with no GUI-cell or import verification; 26.08.2 was source-checked only.

LOGINV is the lower-tail inverse of a lognormal distribution. If ln(X) is normal with mean μ and standard deviation σ, its quantile is exp(μ+σΦ⁻¹(p)). The parameters describe the logarithms, not the arithmetic mean and standard deviation of X itself. Function help.

=LOGINV(probability[;logMean[;logStandardDeviation]])

Probability is required. The optional log-space mean defaults to 0 and the optional log-space standard deviation defaults to 1. The standard deviation must be positive. A probability of zero returns zero; probability one is rejected. Brackets indicate optional arguments and are not entered in the formula. Registration and implementation.

The engine and mathematical columns are separate. Results are rounded to twelve decimal places, or thirteen significant digits in scientific notation for very small or large values. This is a display choice, not an accuracy guarantee. NaN and infinity are nonfinite outputs; an engine error flag is checked separately from those values.

With μ=1 and σ=0.5, the mathematical 95th percentile is approximately 6.186854588195. This is a model cutoff for X, not for ln(X). Keep a clear note in the worksheet that the second and third inputs were fitted in log space.

The median is exp(μ), independent of σ. The first three examples show median 1 for μ=0 and median e for μ=1, even when σ changes to 2.

Median and arithmetic mean are different. For μ=0,σ=1, the median is 1, whereas the mathematical arithmetic mean is exp(0.5)≈1.648721270700. A long upper tail raises the mean. Substituting that arithmetic mean for μ would produce a very different quantile model.

The native roundtrip below uses p=0.75, where the independently computed quantile is approximately 1.963031084158. It is an ordinary positive-input check; it does not validate LOGNORMDIST at zero or with a nonpositive standard deviation.

The executed advanced check was:

=LOGNORMDIST(LOGINV(.75;0;1);0;1)

Its engine result was 0.75.

The lower endpoint zero is the limiting quantile and is not a positive observation with finite logarithm. Probability one would require an unbounded upper quantile and produces #VALUE!. Nonnumeric probability text was converted to zero, whereas TRUE became one and triggered the upper-endpoint error. These coercions are not input-validation rules to imitate.

• Function-specific implementation
• Versioned function help
• Normal Inverse helper
• Conversion helper

The statistical module and value-calculation helpers are byte-identical between the inspected 25.04.2 and 26.08.2 sources. That comparison supports the source discussion but does not establish later-version native output, every locale or arbitrary extreme-parameter accuracy.

NORMINV, LN.