Editing Rounding (section)

===Rounding to an available value===
Finished [[lumber]], writing paper, electronic components, and many other products are usually sold in only a few standard values.

Many design procedures describe how to calculate an approximate value, and then "round" to some standard size using phrases such as "round down to nearest standard value", "round up to nearest standard value", or "round to nearest standard value".<ref>{{cite web |title=Zener Diode Voltage Regulators |url=https://www.kennethkuhn.com/students/ee431/voltage_regulators_zeners.pdf |access-date=2010-11-24 |url-status=live |archive-url=https://web.archive.org/web/20110713143253/http://www.kennethkuhn.com/students/ee431/text/voltage_regulators_zeners.pdf |archive-date=2011-07-13}}</ref><ref>[https://stellafane.org/tm/atm/test/tester-3.html "Build a Mirror Tester"]</ref>

When a set of [[preferred value]]s is equally spaced on a logarithmic scale, choosing the closest [[preferred value]] to any given value can be seen as a form of [[#Scaled rounding|scaled rounding]]. Such rounded values can be directly calculated.<ref>Bruce Trump, Christine Schneider.
"Excel Formula Calculates Standard 1%-Resistor Values". [[Electronic Design]], 2002-01-21. [https://www.electronicdesign.com/components/excel-formula-calculates-standard-1-resistor-values]</ref>