Apa v0.6.0 ApaNumber View Source

APA : Arbitrary Precision Arithmetic - Number String helper - ApaNumber.

Parser to handle number string inputs convert any number string to a tuple of 2 integers: {integer_value, exp}

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Functions

Parses a binary (number string) into an ApaNumber tuple.

This is based on Decimal version of pow10 (cool!!! - is much faster then my version). Extended with :error guard for < 0 - in case that ever happen.

Shifts an ApaNumber to another decimal point to work with the intended integer calculation of two numbers with the same decimal point this operation do not change the mathematical value: ApaNumber.to_string({2, -1}) == "0.2" ~math-equal~ ApaNumber.to_string({20, -2}) == "0.20" and always shift_decimal_point > exp because fillup with zeros reduce non existing zeros is not possible and not necessary to implement returns the shifted ApaNumber tupel or if not possible to shift the input tupel

Creates a string from an ApaNumber tuple.

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from_string(binary)

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from_string(binary()) :: {integer(), integer()} | :error

Parses a binary (number string) into an ApaNumber tuple.

It works with signs, leading and trailing zeros and additional chars will be ignored. If successful, returns a tuple in the form of {integer_value, exponent}:

ApaNumber.from_string("+0003.00e+00000 Dollar") {3, 0}

When the binary cannot be parsed, the atom :error will be returned.

The limit only depends on the internal integers - because of Elixir "unlimited" integers I would say "arbitrary".

Used elixir source from Float module for parsing - nice source of inspiration! Thank you José!

Examples

iex> ApaNumber.from_string("0003") {3, 0}

iex> ApaNumber.from_string("+0003") {3, 0}

iex> ApaNumber.from_string("-0003") {-3, 0}

iex> ApaNumber.from_string("-0000120.1200") {-12012, -2}

iex> ApaNumber.from_string("-0000120.1200") {-12012, -2}

iex> ApaNumber.from_string("-03 Euro") {-3, 0}

iex> ApaNumber.from_string("-0003e-2") {-3, -2}

iex> ApaNumber.from_string("-3e-0002") {-3, -2}

iex> ApaNumber.from_string("3e-12") {3, -12}

iex> ApaNumber.from_string("+0003e+12") {3, 12}

iex> ApaNumber.from_string("+0003e+00000") {3, 0}

iex> ApaNumber.from_string("+0003.00e+00000 Dollar") {3, 0}

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parse(binary)

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parse(binary()) :: {integer(), integer()} | :error

This is based on Decimal version of pow10 (cool!!! - is much faster then my version). Extended with :error guard for < 0 - in case that ever happen.

Examples

iex> ApaNumber.pow10(3) 1000

iex> ApaNumber.pow10(0) 1

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shift_to(arg, shift_decimal_point)

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shift_to({integer(), integer()}, integer()) :: {integer(), integer()}

Shifts an ApaNumber to another decimal point to work with the intended integer calculation of two numbers with the same decimal point this operation do not change the mathematical value: ApaNumber.to_string({2, -1}) == "0.2" ~math-equal~ ApaNumber.to_string({20, -2}) == "0.20" and always shift_decimal_point > exp because fillup with zeros reduce non existing zeros is not possible and not necessary to implement returns the shifted ApaNumber tupel or if not possible to shift the input tupel

Examples

iex> ApaNumber.shift_to({2, -1}, -2) {20, -2}

iex> ApaNumber.shift_to({2, -1}, -4) {2000, -4}

iex> ApaNumber.shift_to({2000, -1}, 0) {200, 0}

iex> ApaNumber.shift_to({2000, -4}, -1) {2, -1}

iex> ApaNumber.shift_to({20, -1}, 0) {2, 0}

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to_string(number_tuple, precision \\ -1, scale \\ -1)

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to_string({integer(), integer()}, integer(), integer()) :: binary() | :error

Creates a string from an ApaNumber tuple.

Examples

iex> ApaNumber.to_string({3, 0}) "3"

iex> ApaNumber.to_string({-3, 0}) "-3"

iex> ApaNumber.to_string({3, 3}) "3000"

iex> ApaNumber.to_string({-12012, -2}) "-120.12"

iex> ApaNumber.to_string({-3997, -6}) "-0.003997"