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'''Trunc''' is a mathematical term that is short for '''truncate''' and appears frequently in [[GemStone IV]] equations that do everything from figuring out a character's [[mana point]] total to how many [[premium point]]s it costs to [[enchant]] an item. For GemStone IV purposes, when one truncates, he/she removes all decimal places after the whole number (integer) without rounding. Thus, 6.1 and 6.9 would both be 6 when truncated.
'''Truncation''' or '''trunc''' is a mathematical term that appears frequently in [[GemStone IV]] equations that do everything from figuring out a character's [[mana point]] total to how many [[premium point]]s it costs to [[enchant]] an item.


To truncate a number, remove all decimal places after the whole number (integer) without rounding. Thus, 6.1 and 6.9 would both be 6 when truncated.
;Example
<div {{prettydiv}}>Enchanting plain item (+5 added) with a starting enchant bonus of +16 to +45<br>1200 + (400 * trunc((current plus - 11) / 5)))= Total premium points required</div><br>
<div {{prettydiv}}>For this example we'll use a "current plus" of 20 (the item is standard 4x enchanted).<br>1200 + (400 * trunc((20 - 11) / 5))) = 1200 + (400 * trunc(9/5)) = 1200 + (400 * '''trunc(1.8)''') = 1200 + (400 * 1) = 1200 + 400 = '''1600'''</div>


== Example ==

Total premium points required for enchanting plain item (+5 added) with a starting enchant bonus of +16 to +45:

:{{math|1200 + (400 * trunc((current plus - 11) / 5)))}}

For this example we'll use a "current plus" of 20 (the item is standard 4x enchanted).

:{{math|1200 + (400 * trunc((20 - 11) / 5))) {{=}} 1200 + (400 * trunc(9/5)) {{=}} 1200 + (400 * '''trunc(1.8)''') {{=}} 1200 + (400 * 1) {{=}} 1200 + 400 {{=}} '''1600'''}}

== "Trunc to 0.xx" ==

In some formulas, instead of truncating to a whole number, values may be truncated to {{math|''n''}} digits after the decimal point. In mathematical terms this is the {{math|trunc(''x'', ''n'')}} function. On the wiki this may also be described as "{{math|trunc to 0.XX}}" for 2 digits, etc.

== Wiki Expressions ==

GSWiki supports inline expression parsing using <code>trunc</code>.

*<code><nowiki>{{#expr: trunc(1.234)}}</nowiki></code> produces {{#expr: trunc(1.234)}}
*<code><nowiki>{{#expr: trunc(1.234 * 100) / 100}}</nowiki></code> produces {{#expr: trunc(1.234 * 100) / 100}}

== References ==
*[https://en.wikipedia.org/wiki/Truncation Truncation] on Wikipedia


[[category:Real Life]]
[[category:Real Life]]

Latest revision as of 15:50, 31 May 2018

Truncation or trunc is a mathematical term that appears frequently in GemStone IV equations that do everything from figuring out a character's mana point total to how many premium points it costs to enchant an item.

To truncate a number, remove all decimal places after the whole number (integer) without rounding. Thus, 6.1 and 6.9 would both be 6 when truncated.

Example

Total premium points required for enchanting plain item (+5 added) with a starting enchant bonus of +16 to +45:

1200 + (400 * trunc((current plus - 11) / 5)))

For this example we'll use a "current plus" of 20 (the item is standard 4x enchanted).

1200 + (400 * trunc((20 - 11) / 5))) = 1200 + (400 * trunc(9/5)) = 1200 + (400 * trunc(1.8)) = 1200 + (400 * 1) = 1200 + 400 = 1600

"Trunc to 0.xx"

In some formulas, instead of truncating to a whole number, values may be truncated to n digits after the decimal point. In mathematical terms this is the trunc(x, n) function. On the wiki this may also be described as "trunc to 0.XX" for 2 digits, etc.

Wiki Expressions

GSWiki supports inline expression parsing using trunc.

  • {{#expr: trunc(1.234)}} produces 1
  • {{#expr: trunc(1.234 * 100) / 100}} produces 1.23

References