OCT2DEC

What it does

OCT2DEC(number)

OCT2DEC(number) converts octal to decimal. The result is a numeric worksheet value.

Try it

=OCT2DEC("55") returns 45. All of these represent the same integer: decimal 45, binary 101101, octal 55, and hexadecimal 2D.

For a negative value, =OCT2DEC("7777777723") returns -45. Accumulation gives 1073741779; the full-width sign bit is set, so subtract 2^30 to get -45. A shorter octal source cannot set that 30-bit sign bit.

Quirks

These engineering conversions use signed fixed-width encodings, not arbitrary-length integers. The source accepts at most ten digits; a full ten-digit encoding uses 30-bit two’s complement. 7777777777 represents minus one. Invalid source digits or an oversized input give #NUM!. Quote source digits to keep leading zeros and prevent worksheet number parsing from changing the input.

How to implement

Separate input parsing, signed interpretation and output formatting. Uppercase the source, validate its digit set and length, and accumulate raw=raw*8+digit with checked integer arithmetic. Only a full ten-digit source with its top bit set is negative: subtract 2^30 to obtain signed integer v. Return v as a number. The 45 example is an exact integer at every step. Do not infer sign merely from the first source character of a short encoding.

Rust code

11 oct2dec "OCT2DEC" (1, 1) [V "number"] |s, a, sv| { to_decimal(s, a, radix::oct2dec_kernel) }

pub fn oct2dec_kernel(number: &str) -> Result<f64, WorksheetErrorCode> {
    source_to_decimal_kernel(number, OCT_SPEC)
}

No implementation has been published with a Handbook test suite for this function.

Version differences

The recorded environments below distinguish a reading from a same-input comparison. Counts describe captured inputs in each environment; overlapping captures and comparisons are not totals of unique worksheet calls.

The record contains no same-input comparison between these environments. Reading different inputs on different builds does not establish either a version change or cross-build agreement.

Recorded environments and comparison details.

Alternatives

DEC2OCT converts in the reverse direction. BASE and DECIMAL provide general radix conversion with different sign rules. A full-width negative engineering encoding is not a minus-prefixed numeral; choose the pair whose sign convention fits your input.

Named variants

No named variants are recorded yet.