Extension:BCmath/用語集
Glossary for BCmath is a list of core terms and concepts for bcmath, or arbitrary-precision arithmetic.
Terms and concepts
- Arbitrary precision
- When calculations are not limited by specific register sizes it is referred to as arbitrary precision.
- Infinity (∞)
- Infinite numbers are valid numbers that are represented with a particular Unicode symbol, the infinity (U+221E) codepoint.
- An infinite number can have a sign, both a plus infinity (+∞) and a minus infinity (-∞).
- NaN (nan)
- Not-a-Number is the value of a calculation that has no valid representation as a number. It is called
nan
internally. - A NaN can have a payload that further clarify what it is or represents.
- Operation
- Numbers are combined they are said to be operands to an operation.
- Operations and operands can have their own names, like addition has addend and augend.
- Payload
- When calculations generates a NaN, then additional information might be added to the payload.
- Payloads might be inspected in the console, but will otherwise be silently forgotten.
- Scale (scale)
- The scale is how the number is shifted to process it efficiently. It is given as the argument
scale
to most operations. - The BCmath extension tries to estimate the scale factor if it is missing.
- Self (self)
- The actual instance, the “self”, in this case holding a number. It is called
self
internally.
演算
- add
- Add the addend to augend.
- sub
- Subtract the subtrahend from minuend.
- mul
- Multiply the multiplicator with multiplier.
- div
- Divide the divisor from dividend
- mod
- Modulus the divisor from dividend.
- pow
- Power the base to exponent.
- powmod
- Power the base to exponent and then modulus divisor.
- sqrt
- Square root of the operand.
- eq
- Is left side equal to right side.
- lt
- Is left side less than right side.
- le
- Is left side less than or equal to right side.
- {{anchor|gt|greater-than} gt
- Is left side greater than right side.
- ge
- Is left side greater than or equal to right side.
外部リンク
- UTS #35: Unicode LDML: Numbers. (Unicode) Accessed September 21, 2019.
- Number Patterns - CLDR - Unicode Common Locale Data Repository. Accessed September 21, 2019.
- Number Symbols - CLDR - Unicode Common Locale Data Repository. Accessed September 22, 2019.
- CLDR Releases/Downloads - CLDR - Unicode Common Locale Data Repository. Accessed September 22, 2019.
- PHP: BCMath Arbitrary Precision Mathematics