3 ms·
When dealing with numbers, the notation means "order of magnitude," which is the nearest power of 10. Strictly, this places is between 5 and 50 (4 rounds down
by dhimes 12y ago
When dealing with numbers, the notation means "order of magnitude," which is the nearest power of 10. Strictly, this places is between 5 and 50 (4 rounds down to 1, 51 rounds up to 100).
Most people use it a little more loosely in conversation. More than 1, not 100, etc.
- stcredzero 12y agoI didn't know this. I'm used to just talking about "order of magnitude."
- dllthomas 12y agoWhile I've occasionally seen O(...) used to mean "approximate upper bound" or even "approximate bound" in a more general way than the math for Big-O notation would permit, I've assumed it was either error or analogy, not a specific other function. Can you give a citation for this being an established usage? (Note that I'm certainly familiar with orders of magnitude, just not this notation for them.)
- dhimes 12y agoIt may be informal. I seem to recall people also using ~ for this, as in "The detector is measuring eV, but this effect is ~ meV |O(meV) so we won't see it."