FastDecimal

https://hexdocs.pm/fastdecimal
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FastDecimal is a pure-Elixir arbitrary-precision decimal arithmetic library designed for high...
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### Division examples

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Examples demonstrating exact and inexact division results.

```elixir
iex> FastDecimal.div(FastDecimal.new("10"), FastDecimal.new("2"))
%FastDecimal{coef: 5, exp: 0}

iex> FastDecimal.div(FastDecimal.new("1"), FastDecimal.new("2"))
%FastDecimal{coef: 5, exp: -1}

iex> FastDecimal.div(FastDecimal.new("10.0"), FastDecimal.new("2"))
%FastDecimal{coef: 50, exp: -1}
```

```elixir
iex> FastDecimal.div(FastDecimal.new("10"), FastDecimal.new("3"), precision: 5)
%FastDecimal{coef: 33333, exp: -4}
```

--------------------------------

### Compare Decimal version parsing behavior

Source: https://hexdocs.pm/fastdecimal/migration.html

Examples showing how Decimal v2.4 and v3.0+ handle parsing limits compared to FastDecimal's approach.

```elixir
# decimal v2.4 (opt-in):
Decimal.parse("1e1000", max_exponent: 100)            # → :error
Decimal.cast(input, max_digits: 50)                   # → :error if too long

# decimal v3.0+ (rejected by default):
Decimal.parse("1.012345678901234567890123456789012345")  # → :error (35 sig digits > 34)
Decimal.parse("1e7000")                                  # → :error (exp > 6144)
Decimal.new("1e7000", max_exponent: :infinity)           # explicit opt-out
```

--------------------------------

### Exact division representation changes

Source: https://hexdocs.pm/fastdecimal/changelog.html

Examples showing the transition from un-reduced coefficients to GDA ideal exponent forms for exact division results.

```elixir
div(10, 2)     → %FastDecimal{coef: 5, exp: 0}     (was coef: 5×10^27)
div(1, 2)      → %FastDecimal{coef: 5, exp: -1}
div("10.0", 2) → %FastDecimal{coef: 50, exp: -1}   ("5.0", like Decimal)
div(0, 3)      → %FastDecimal{coef: 0, exp: 0}     (was {0, -28})
```

--------------------------------

### Run Benchmarks and Tests

Source: https://hexdocs.pm/fastdecimal/index.html

Commands to execute the test suite and various benchmark scripts for performance analysis.

```bash
mix deps.get
mix test                  # 19 doctests + 41 properties + 325 unit tests = 385 total
mix bench                 # → bench/summary.exs (headline table, ~1 minute)
mix bench.all             # → every bench file end-to-end (~20 minutes)

# Or run a specific bench:
mix run bench/division.exs        # div / div_int / div_rem / rem
mix run bench/rounding.exs        # round/3 × 7 modes
mix run bench/sqrt.exs            # sqrt at 6 precisions
mix run bench/conversion.exs      # to_string formats, cast, to_int/float
mix run bench/special_values.exs  # NaN/Inf overhead
mix run bench/realistic.exs       # fintech-style workloads
mix run bench/batch.exs           # sum/product at 4 list sizes
mix run bench/profile.exs         # per-op time + alloc + reductions
mix run bench/parse.exs           # parser strategy shootout
mix run bench/representation.exs  # struct vs raw tuple
mix run bench/targeted.exs        # parse / compare-large-gap / normalize-multi-zero / to_integer / div fast paths
mix run bench/disasm.exs          # BEAM bytecode dump
```

--------------------------------

### Run performance benchmarks

Source: https://hexdocs.pm/fastdecimal/index.html

Command to execute the library's internal benchmark suite.

```bash
mix bench
```

--------------------------------

### Assess migration complexity via grep

Source: https://hexdocs.pm/fastdecimal/migration.html

Run these commands in your project root to identify usage of features that differ between decimal and FastDecimal.

```bash
# 1. Do you use Decimal.Context.set / with / get / update?
grep -rn "Decimal.Context" lib/ test/

# 2. Do you have %Decimal{...} struct literals (constructing or pattern matching)?
grep -rn "%Decimal{" lib/ test/

# 3. Do you depend on signaling NaN (sNaN) vs quiet NaN distinction?
grep -rn ":sNaN\|signaling" lib/

# 4. Do you read Decimal.Context flags after operations?
grep -rn "Decimal.Context.*flags\|\.flags" lib/ test/

# 5. Do you depend on -0 being distinguishable from 0?
grep -rn "Decimal.new(\"-0\")" lib/ test/
```

--------------------------------

### Migrate Pricing Module to FastDecimal

Source: https://hexdocs.pm/fastdecimal/migration.html

Shows the minimal change required to migrate a module by aliasing FastDecimal.Compat as Decimal.

```elixir
defmodule Pricing do
  def apply_fee(price, fee_bps) do
    Decimal.mult(price, Decimal.add(Decimal.div(fee_bps, 10_000), 1))
  end

  def spread(bid, ask) do
    diff = Decimal.sub(ask, bid)
    mean = Decimal.add(ask, bid) |> Decimal.div(2)

    diff |> Decimal.div(mean) |> Decimal.mult(10_000) |> Decimal.round(4)
  end
end
```

```elixir
 defmodule Pricing do
+  alias FastDecimal.Compat, as: Decimal

   def apply_fee(price, fee_bps) do
     Decimal.mult(price, Decimal.add(Decimal.div(fee_bps, 10_000), 1))
   end

   def spread(bid, ask) do
     diff = Decimal.sub(ask, bid)
     mean = Decimal.add(ask, bid) |> Decimal.div(2)

     diff |> Decimal.div(mean) |> Decimal.mult(10_000) |> Decimal.round(4)
   end
 end
```

--------------------------------

### Perform arithmetic operations with FastDecimal

Source: https://hexdocs.pm/fastdecimal/index.html

Demonstrates basic arithmetic, summation, rounding, and precision-controlled division using the FastDecimal sigil and module functions.

```elixir
import FastDecimal

~d"1.23"
|> FastDecimal.add(~d"4.567")
|> FastDecimal.mult(~d"2")
|> FastDecimal.to_string()
# => "11.594"

FastDecimal.sum([~d"1.5", ~d"2.5", ~d"3"])
# => ~d"7.0"

FastDecimal.round(~d"1.236", 2)         # ~d"1.24"
FastDecimal.sqrt(~d"2", precision: 10)   # ~d"1.414213562"
FastDecimal.div(~d"10", ~d"3", precision: 5)  # ~d"3.3333"
```

--------------------------------

### Create new decimal from components

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Decimal-style 3-arg constructor: sign (1 or -1), coef, exp.

```elixir
@spec new(1 | -1, non_neg_integer(), integer()) :: FastDecimal.t()
```

--------------------------------

### FastDecimal.Compat Functions

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

A collection of functions for decimal arithmetic, comparison, and creation.

```APIDOC
## integer?(d)
Checks if the provided input is an integer.

## lt?(a, b)
Compares two inputs and returns true if the first is less than the second.

## max(a, b)
Returns the maximum of two decimal inputs.

## min(a, b)
Returns the minimum of two decimal inputs.

## minus(a)
Returns the negation of the input decimal.

## mult(a, b)
Multiplies two decimal inputs.

## multiply(a, b)
Alias for mult/2.

## nan()
Returns a NaN (Not a Number) decimal value.

## nan?(a)
Checks if the input is NaN.

## neg_inf()
Returns a negative infinity decimal value.

## negate(a)
Alias for minus/1.

## negative?(a)
Checks if the input is negative.

## new(input)
Creates a new decimal from the given input.

## new(sign, coef, exp)
Creates a new decimal using sign (1 or -1), coefficient, and exponent.

## normalize(a)
Normalizes the decimal value.

## plus(a)
Returns the positive value of the input.

## positive?(a)
Checks if the input is positive.

## reduce(a)
Alias for normalize/1.

## rem(a, b)
Calculates the remainder of two decimal inputs.
```

--------------------------------

### Migrating to FastDecimal.Compat

Source: https://hexdocs.pm/fastdecimal/index.html

Use the FastDecimal.Compat module to mirror the decimal library's public surface while auto-coercing various input types.

```elixir
defmodule MyLedger do
  alias FastDecimal.Compat, as: Decimal   # add this line, rest stays the same

  def total(items) do
    Enum.reduce(items, Decimal.new(0), fn item, acc ->
      Decimal.add(acc, item.amount)
    end)
  end
end
```

--------------------------------

### product(list)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Calculates the product of a list of FastDecimals.

```APIDOC
## product([t()])

### Description
Product of a list of FastDecimals.

### Signature
`@spec product([t()]) :: t()`
```

--------------------------------

### Use is_decimal guard macro

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Demonstrates using the is_decimal guard-safe predicate within a module.

```elixir
defmodule MyMod do
  require FastDecimal

  def total(d) when FastDecimal.is_decimal(d) do
    # ...
  end
end
```

--------------------------------

### Constructing FastDecimal values

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Create new decimal instances using string parsing or explicit coefficient and exponent arguments.

```elixir
iex> FastDecimal.new("1.23")
%FastDecimal{coef: 123, exp: -2}

iex> FastDecimal.new(123, -2)
%FastDecimal{coef: 123, exp: -2}
```

--------------------------------

### Apply the FastDecimal Compat shim

Source: https://hexdocs.pm/fastdecimal/migration.html

Use the Compat module to alias FastDecimal as Decimal, allowing existing code to route through the shim.

```elixir
 defmodule MyApp.Ledger do
+  alias FastDecimal.Compat, as: Decimal

   def total(items) do
     Enum.reduce(items, Decimal.new(0), fn item, acc ->
       Decimal.add(acc, item.amount)
     end)
   end

   def round_to_cents(d), do: Decimal.round(d, 2, :half_even)
 end
```

--------------------------------

### Benchmark workload performance with Benchee

Source: https://hexdocs.pm/fastdecimal/migration.html

Use this snippet in a test or iex session to compare the performance of your existing decimal-based code against the new FastDecimal implementation.

```elixir
Benchee.run(%{
  "before (decimal)" => fn -> my_workload_using_decimal() end,
  "after (fastdecimal)" => fn -> my_workload_using_fastdecimal() end
}, time: 5, warmup: 2)
```

--------------------------------

### new(int) / new(coef, exp)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Creates a new FastDecimal instance from an integer/string or coefficient and exponent.

```APIDOC
## new(String.t() | integer())

### Description
Creates a new FastDecimal from a string or integer.

### Signature
`@spec new(String.t() | integer()) :: t()`

## new(integer(), integer())

### Description
Creates a new FastDecimal from a coefficient and exponent.

### Signature
`@spec new(integer(), integer()) :: t()`
```

--------------------------------

### Construct FastDecimal values

Source: https://hexdocs.pm/fastdecimal/index.html

Create decimal values using sigils, runtime parsing, or direct conversion from other types.

```elixir
import FastDecimal

~d"1.23"                          # Compile-time literal (zero parse cost at runtime)
~d"1.23e10"                       # Scientific notation
~d"Infinity"                      # +∞
~d"-Inf"                          # -∞
~d"NaN"                           # NaN

FastDecimal.new("1.23")           # Runtime parse, raises on bad input
FastDecimal.new(42)               # From integer
FastDecimal.new(123, -2)          # From coef + exp
FastDecimal.parse("1.23")         # {:ok, t} | :error  — no raise
FastDecimal.cast(value)           # Soft parse, accepts FastDecimal/Decimal/int/string/float/nil
```

--------------------------------

### Comparison and predicates

Source: https://hexdocs.pm/fastdecimal/index.html

Compare decimal values or check their properties.

```elixir
FastDecimal.compare(a, b)         # :lt | :eq | :gt | :nan
FastDecimal.equal?(a, b)
FastDecimal.lt?(a, b) ; FastDecimal.gt?(a, b)
FastDecimal.min(a, b) ; FastDecimal.max(a, b)

FastDecimal.zero?(d) ; FastDecimal.positive?(d) ; FastDecimal.negative?(d)
FastDecimal.nan?(d)  ; FastDecimal.inf?(d)     ; FastDecimal.finite?(d)
```

--------------------------------

### Refactor pattern matching and construction

Source: https://hexdocs.pm/fastdecimal/migration.html

Replace struct pattern matching with predicate functions and use the 3-arg constructor for manual struct creation.

```elixir
# Before:
case decimal do
  %Decimal{sign: -1} -> :negative
  %Decimal{sign: 1, coef: 0} -> :zero
  %Decimal{} -> :positive
end

# After: use predicates instead of pattern matching internals
cond do
  Decimal.negative?(decimal) -> :negative
  Decimal.zero?(decimal) -> :zero
  true -> :positive
end
```

```elixir
# Before:
%Decimal{sign: 1, coef: 123, exp: -2}
%Decimal{sign: -1, coef: 50, exp: -1}

# After: use the shimmed 3-arg constructor
Decimal.new(1, 123, -2)
Decimal.new(-1, 50, -1)
```

--------------------------------

### Create new FastDecimal from coefficient and exponent

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Constructs a new FastDecimal using explicit coefficient and exponent values.

```elixir
@spec new(integer(), integer()) :: t()
```

--------------------------------

### FastDecimal.Compat API

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

The FastDecimal.Compat module provides a set of functions that mirror the standard Decimal library API, allowing for easy migration by aliasing the module.

```APIDOC
## Functions

### abs(a)
Returns the absolute value of the input.

### add(a, b)
Adds two decimal values.

### cast(value)
Soft constructor that returns `{:ok, t} | :error`. Mirrors Ecto.Type.cast/1 behavior.

### div(a, b, opts \\ [])
Performs division. Defaults to precision 28. Accepts `precision` and `rounding` options.

### new(input)
Creates a new decimal from the provided input.

### new(arg1, coef, exp)
Decimal-style 3-arg constructor: sign (1 or -1), coefficient, and exponent.

### round(a, places \\ 0, mode \\ :half_up)
Rounds the decimal value to the specified number of places using the given rounding mode.

### sqrt(a, opts \\ [])
Calculates the square root of the decimal value.
```

--------------------------------

### Create new decimal

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Constructs a new FastDecimal from the input.

```elixir
@spec new(input()) :: FastDecimal.t()
```

--------------------------------

### Add FastDecimal Dependency

Source: https://hexdocs.pm/fastdecimal/migration.html

Add the FastDecimal dependency to your mix.exs file alongside the existing decimal library.

```elixir
{:fastdecimal, "~> 1.0"}
```

--------------------------------

### Define to_string_format type

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Supported output formats for string conversion.

```elixir
@type to_string_format() :: :normal | :scientific | :raw | :xsd
```

--------------------------------

### Using the ~d sigil

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Define decimal literals at compile-time to avoid runtime parsing costs.

```elixir
import FastDecimal
~d"1.23"   # => %FastDecimal{coef: 123, exp: -2}
```

--------------------------------

### Use guard-safe macros

Source: https://hexdocs.pm/fastdecimal/index.html

Use the provided macro for guard-safe type checking.

```elixir
require FastDecimal

def process(d) when FastDecimal.is_decimal(d), do: ...
```

--------------------------------

### Compare values for less than

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Checks if the first value is less than the second.

```elixir
@spec lt?(input(), input()) :: boolean()
```

--------------------------------

### Add FastDecimal dependency

Source: https://hexdocs.pm/fastdecimal/migration.html

Include both fastdecimal and the original decimal library in your dependencies.

```elixir
def deps do
  [
    {:fastdecimal, "~> 1.0"},
    {:decimal, "~> 2.1"}  # keep — Ecto and other libs still pull it in
  ]
end
```

--------------------------------

### to_string(a, format)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Converts a decimal value to its string representation.

```APIDOC
## to_string(a, format)

### Description
Converts the input decimal to a string, optionally using a specific format.

### Signature
`to_string(input(), FastDecimal.to_string_format()) :: String.t()`
```

--------------------------------

### Calculate quotient and remainder with div_rem/2

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Returns a tuple containing the quotient and remainder, where the quotient is computed via integer division.

```elixir
@spec div_rem(t(), t()) :: {t(), t()}
```

```elixir
iex> FastDecimal.div_rem(FastDecimal.new("10"), FastDecimal.new("3"))
{%FastDecimal{coef: 3, exp: 0}, %FastDecimal{coef: 1, exp: 0}}
```

--------------------------------

### Check for decimal v2.4 / v3.x specific API usage

Source: https://hexdocs.pm/fastdecimal/migration.html

Identify usage of :max_digits and :max_exponent options which must be removed during migration.

```bash
grep -rn "Decimal\.\(parse\|cast\|new\)\(.*,.*max_\|Decimal\.to_string\(.*,.*max_" lib/ test/
```

--------------------------------

### Comparison & Predicates

Source: https://hexdocs.pm/fastdecimal/readme.html

Functions for comparing decimal values and checking their properties.

```APIDOC
## Comparison Methods
- `FastDecimal.compare(a, b)`: Returns `:lt`, `:eq`, `:gt`, or `:nan`.
- `FastDecimal.equal?(a, b)`
- `FastDecimal.lt?(a, b)`
- `FastDecimal.gt?(a, b)`
- `FastDecimal.min(a, b)`
- `FastDecimal.max(a, b)`

## Predicates
- `FastDecimal.zero?(d)`, `FastDecimal.positive?(d)`, `FastDecimal.negative?(d)`
- `FastDecimal.nan?(d)`, `FastDecimal.inf?(d)`, `FastDecimal.finite?(d)`
```

--------------------------------

### Convert to string

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Converts a decimal-compatible input to its string representation, optionally using a specific format.

```elixir
@spec to_string(input()) :: String.t()
```

```elixir
@spec to_string(input(), FastDecimal.to_string_format()) :: String.t()
```

--------------------------------

### Create negative infinity

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Returns a negative infinity decimal value.

```elixir
@spec neg_inf() :: FastDecimal.t()
```

--------------------------------

### Batch operations

Source: https://hexdocs.pm/fastdecimal/index.html

Perform operations on lists of decimals efficiently.

```elixir
FastDecimal.sum(list)             # Tight Elixir-side reduce
FastDecimal.product(list)
```

--------------------------------

### to_string(decimal, format)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Formats a FastDecimal as a string using various supported formats.

```APIDOC
## to_string(decimal, format)

### Description
Formats a decimal as a string. Supported formats include :normal, :scientific, :raw, and :xsd.

### Signature
`to_string(t(), to_string_format()) :: String.t()`

### Parameters
- **decimal** (t()) - The FastDecimal to format.
- **format** (to_string_format()) - The formatting style to apply (defaults to :normal).
```

--------------------------------

### Locate struct literals and context usage

Source: https://hexdocs.pm/fastdecimal/migration.html

Use grep to find occurrences of Decimal structs or context usage that require manual refactoring.

```bash
grep -rn "%Decimal{" lib/ test/
```

```bash
grep -rn "Decimal.Context" lib/ test/
```

--------------------------------

### add(a, b)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Adds two decimal values.

```APIDOC
## add(a, b)

### Signature
`add(input(), input()) :: FastDecimal.t()`
```

--------------------------------

### Define from_integer specification

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Specifies the from_integer function signature.

```elixir
@spec from_integer(integer()) :: t()
```

--------------------------------

### Sum a List of FastDecimals

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Sums a list of FastDecimals using an inlined, recursion-flat approach to avoid function call overhead.

```elixir
@spec sum([t()]) :: t()
```

--------------------------------

### Perform integer division with div_int/2

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Truncates the fractional part toward zero, returning a result with an exponent of 0.

```elixir
@spec div_int(t(), t()) :: t()
```

```elixir
iex> FastDecimal.div_int(FastDecimal.new("10.5"), FastDecimal.new("3"))
%FastDecimal{coef: 3, exp: 0}
```

--------------------------------

### Compare two decimals

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Compares two FastDecimal values and returns the relationship.

```elixir
@spec compare(t(), t()) :: :lt | :eq | :gt | :nan
```

--------------------------------

### Alias FastDecimal.Compat as Decimal

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Use this alias to route existing Decimal calls to the FastDecimal compatibility layer.

```elixir
alias FastDecimal.Compat, as: Decimal
```

--------------------------------

### add(a, b)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Adds two FastDecimal values together.

```APIDOC
## add(t(), t())

### Description
Adds two FastDecimal values together.

### Signature
`add(t(), t()) :: t()`
```

--------------------------------

### lt?(a, b)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Checks if the first decimal is less than the second.

```APIDOC
## lt?(a, b)

### Signature
`@spec lt?(t(), t()) :: boolean()`
```

--------------------------------

### FastDecimal.div/3

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Performs division with configurable precision.

```APIDOC
## FastDecimal.div(a, b, opts \\ [])

### Description
Divides two decimals. Unlike other operations, this requires a precision argument to handle non-terminating decimals.

### Parameters
- **a** (t()) - Dividend
- **b** (t()) - Divisor
- **opts** (keyword) - Optional configuration, including `precision`

### Example
```elixir
FastDecimal.div(FastDecimal.new("10"), FastDecimal.new("3"), precision: 5)
```
```

--------------------------------

### div(a, b, opts)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Performs division on two decimal values with optional precision and rounding settings.

```APIDOC
## div(a, b, opts \\ [])

### Signature
`div(input(), input(), keyword()) :: FastDecimal.t()`
```

--------------------------------

### sqrt(a, opts)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Calculates the square root of a decimal value.

```APIDOC
## sqrt(a, opts)

### Description
Computes the square root of the input decimal with optional configuration.

### Signature
`sqrt(input(), keyword()) :: FastDecimal.t()`
```

--------------------------------

### Performing arithmetic operations

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Execute exact addition or division with specified precision.

```elixir
iex> FastDecimal.add(FastDecimal.new("1.23"), FastDecimal.new("4.567"))
%FastDecimal{coef: 5797, exp: -3}

iex> FastDecimal.div(FastDecimal.new("10"), FastDecimal.new("3"), precision: 5)
%FastDecimal{coef: 33333, exp: -4}
```

--------------------------------

### from_integer(int)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Creates a FastDecimal from an integer.

```APIDOC
## from_integer(int)

### Signature
`@spec from_integer(integer()) :: t()`
```

--------------------------------

### Compare two values

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Compares two inputs and returns the relationship status.

```elixir
@spec cmp(input(), input()) :: :lt | :eq | :gt | :nan
```

```elixir
@spec compare(input(), input()) :: :lt | :eq | :gt | :nan
```

--------------------------------

### FastDecimal.new/1,2

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Constructs a new FastDecimal struct from a string or integer/exponent pair.

```APIDOC
## FastDecimal.new(value)

### Description
Creates a new FastDecimal instance.

### Signature
- `new(string)`
- `new(coef, exp)`

### Examples
```elixir
FastDecimal.new("1.23")
FastDecimal.new(123, -2)
```
```

--------------------------------

### inf()

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Returns the +∞ sentinel value.

```APIDOC
## inf()

### Signature
`@spec inf() :: t()`
```

--------------------------------

### Check for zero

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Determines if the provided input is equivalent to zero.

```elixir
@spec zero?(input()) :: boolean()
```

--------------------------------

### equal?(a, b)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Checks if two decimal values are equal.

```APIDOC
## equal?(a, b)

### Signature
`equal?(input(), input()) :: boolean()`
```

--------------------------------

### Calculate Square Root with FastDecimal

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Computes the square root using the Newton-Raphson method with configurable precision.

```elixir
@spec sqrt(
  t(),
  keyword()
) :: t()
```

```elixir
iex> FastDecimal.sqrt(FastDecimal.new("4"))
%FastDecimal{coef: 2, exp: 0}

iex> FastDecimal.sqrt(FastDecimal.new("2"), precision: 10)
%FastDecimal{coef: 1414213562, exp: -9}
```

--------------------------------

### Handle precision context changes

Source: https://hexdocs.pm/fastdecimal/migration.html

Replace implicit context-based precision with explicit per-call precision or a custom wrapper module.

```elixir
# Before (implicit context):
def init(_) do
  Decimal.Context.set(%Decimal.Context{precision: 18, rounding: :half_even})
  # ... downstream code calls Decimal.div(a, b) with implicit precision: 18
end

# After (explicit per-call):
@precision 18
@rounding :half_even

defp my_div(a, b), do: FastDecimal.div(a, b, precision: @precision, rounding: @rounding)
# ... use my_div instead of Decimal.div throughout
```

```elixir
defmodule MyApp.Decimal do
  @precision 18
  @rounding :half_even

  def div(a, b), do: FastDecimal.div(a, b, precision: @precision, rounding: @rounding)
  def sqrt(a), do: FastDecimal.sqrt(a, precision: @precision)
  def round(a, places), do: FastDecimal.round(a, places, @rounding)

  # delegate the rest to FastDecimal — they don't take precision
  defdelegate add(a, b), to: FastDecimal
  defdelegate sub(a, b), to: FastDecimal
  defdelegate mult(a, b), to: FastDecimal
  defdelegate compare(a, b), to: FastDecimal
  # ... etc
end
```

--------------------------------

### Update is_decimal Import

Source: https://hexdocs.pm/fastdecimal/migration.html

Update the import statement for the is_decimal macro to use the FastDecimal implementation.

```elixir
-import Decimal.Macros, only: [is_decimal: 1]
+import FastDecimal, only: [is_decimal: 1]
```

--------------------------------

### Convert to float

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Converts a decimal-compatible input to a standard float.

```elixir
@spec to_float(input()) :: float()
```

--------------------------------

### Compare decimals with equal?/2

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Checks for equality between two decimals, noting that NaN values never compare as equal.

```elixir
@spec equal?(t(), t()) :: boolean()
```

--------------------------------

### FastDecimal Construction

Source: https://hexdocs.pm/fastdecimal/readme.html

Methods for creating FastDecimal types from various inputs including strings, integers, and scientific notation.

```APIDOC
## FastDecimal.new/1,2

### Description
Creates a new FastDecimal instance. `new/1` parses input and raises on error, while `new/2` constructs from coefficient and exponent.

## FastDecimal.parse/1

### Description
Parses a string into a FastDecimal instance, returning `{:ok, t}` or `:error` without raising.

## FastDecimal.cast/1

### Description
Performs a soft parse of various input types (Decimal, int, string, float, nil) into a FastDecimal.
```

--------------------------------

### Return positive value

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Returns the positive version of the input.

```elixir
@spec plus(input()) :: FastDecimal.t()
```

--------------------------------

### to_float(a)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Converts a decimal value to a float.

```APIDOC
## to_float(a)

### Description
Converts the input decimal to a floating-point number.

### Signature
`to_float(input()) :: float()`
```

--------------------------------

### Division with remainder

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Performs division and returns both the quotient and remainder.

```elixir
@spec div_rem(input(), input()) :: {FastDecimal.t(), FastDecimal.t()}
```

--------------------------------

### min(a, b)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Returns the smaller of two decimals.

```APIDOC
## min(a, b)

### Description
The smaller of two decimals. If exactly one operand is NaN, the number is returned (IEEE 754 minNum semantics, matching Decimal.min/2); NaN is returned only when both operands are NaN.

### Signature
`@spec min(t(), t()) :: t()`
```

--------------------------------

### zero?(a)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Checks if a decimal value is zero.

```APIDOC
## zero?(a)

### Description
Returns true if the input decimal is zero, otherwise false.

### Signature
`zero?(input()) :: boolean()`
```

--------------------------------

### Define min specification

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Specifies the minimum value function signature.

```elixir
@spec min(t(), t()) :: t()
```

--------------------------------

### FastDecimal.add/2

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Performs exact addition of two FastDecimal values.

```APIDOC
## FastDecimal.add(a, b)

### Description
Adds two FastDecimal structs. The operation is mathematically exact.

### Parameters
- **a** (t()) - The first decimal
- **b** (t()) - The second decimal

### Example
```elixir
FastDecimal.add(FastDecimal.new("1.23"), FastDecimal.new("4.567"))
```
```

--------------------------------

### Parse a string to FastDecimal

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Attempts to parse a string into a FastDecimal, returning {:ok, t()} or :error.

```elixir
@spec parse(String.t()) :: {:ok, t()} | :error
```

--------------------------------

### parse(str)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Parses a string into a FastDecimal.

```APIDOC
## parse(String.t())

### Description
Parses a string into a FastDecimal.

### Signature
`@spec parse(String.t()) :: {:ok, t()} | :error`
```

--------------------------------

### neg_inf()

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Returns the -∞ sentinel value.

```APIDOC
## neg_inf()

### Signature
`@spec neg_inf() :: t()`
```

--------------------------------

### Convert to integer

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Converts a decimal-compatible input to an integer.

```elixir
@spec to_integer(input()) :: integer()
```

--------------------------------

### Check if finite

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Determines if the input is a finite number.

```elixir
@spec finite?(input()) :: boolean()
```

--------------------------------

### Check if infinite

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Determines if the input is infinite.

```elixir
@spec inf?(input()) :: boolean()
```

--------------------------------

### is_decimal(value)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Guard-safe predicate. True when the argument is a %FastDecimal{} struct.

```APIDOC
## is_decimal(value)

### Description
Guard-safe predicate. True when the argument is a %FastDecimal{} struct. Mirrors Decimal.Macros.is_decimal/1 so it can be drop-in-substituted.
```

--------------------------------

### Comparing decimal values

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Check for equality or compare values, noting that trailing zeros in the representation do not affect numerical equality.

```elixir
iex> FastDecimal.compare(FastDecimal.new("1.10"), FastDecimal.new("1.1"))
:eq

iex> FastDecimal.equal?(FastDecimal.new("1.10"), FastDecimal.new("1.1"))
true
```

--------------------------------

### gt?(a, b)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Checks if the first decimal is greater than the second.

```APIDOC
## gt?(a, b)

### Signature
`@spec gt?(t(), t()) :: boolean()`
```

--------------------------------

### sum(list)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Calculates the sum of a list of FastDecimal values.

```APIDOC
## sum(list)

### Description
Sums a list of FastDecimals. This implementation is optimized to be recursion-flat and avoids the overhead of anonymous function calls.

### Signature
`sum([t()]) :: t()`

### Parameters
- **list** ([t()]) - A list of FastDecimal structs to sum.
```

--------------------------------

### nan()

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Returns the NaN sentinel value.

```APIDOC
## nan()

### Signature
`@spec nan() :: t()`
```

--------------------------------

### Calculate product of a list

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Computes the product of a list of FastDecimal values.

```elixir
@spec product([t()]) :: t()
```

--------------------------------

### Define input type

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Defines the accepted input types for FastDecimal functions.

```elixir
@type input() :: FastDecimal.t() | Decimal.t() | integer() | binary() | float() | nil
```

--------------------------------

### Add two decimals

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Performs addition on two FastDecimal values.

```elixir
@spec add(t(), t()) :: t()
```

--------------------------------

### FastDecimal.compare/2

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Compares two FastDecimal values.

```APIDOC
## FastDecimal.compare(a, b)

### Description
Compares two decimals and returns :eq, :lt, or :gt.

### Example
```elixir
FastDecimal.compare(FastDecimal.new("1.10"), FastDecimal.new("1.1"))
```
```

--------------------------------

### Add two values

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Performs addition on two inputs.

```elixir
@spec add(input(), input()) :: FastDecimal.t()
```

--------------------------------

### Format FastDecimal as String

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Converts a FastDecimal to a string using specified formatting options like :normal, :scientific, :raw, or :xsd.

```elixir
@spec to_string(t(), to_string_format()) :: String.t()
```

--------------------------------

### Convert decimal values

Source: https://hexdocs.pm/fastdecimal/index.html

Convert decimals to strings, integers, or floats, and normalize representations.

```elixir
FastDecimal.to_string(d)              # "1.23"
FastDecimal.to_string(d, :scientific) # "1.23" — IEEE compact (only emits E for very small/large)
FastDecimal.to_string(d, :raw)        # "123E-2"
FastDecimal.to_string(d, :xsd)        # XSD canonical (= :normal for our repr)

FastDecimal.to_integer(d)             # raises on fractional
FastDecimal.to_float(d)               # lossy for non-terminating binaries
FastDecimal.normalize(d)              # strips trailing zeros
```

--------------------------------

### Check equality

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Checks if two inputs are equal.

```elixir
@spec eq?(input(), input()) :: boolean()
```

```elixir
@spec equal?(input(), input()) :: boolean()
```

--------------------------------

### to_integer(a)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Converts a decimal value to an integer.

```APIDOC
## to_integer(a)

### Description
Converts the input decimal to an integer.

### Signature
`to_integer(input()) :: integer()`
```

--------------------------------

### Convert from float

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Converts a float to a FastDecimal.

```elixir
@spec from_float(float()) :: FastDecimal.t()
```

--------------------------------

### abs(a)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Calculates the absolute value of the input.

```APIDOC
## abs(a)

### Signature
`abs(input()) :: FastDecimal.t()`
```

--------------------------------

### Divide two values

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Performs division with optional precision and rounding settings.

```elixir
@spec div(input(), input(), keyword()) :: FastDecimal.t()
```

--------------------------------

### Define lt? specification

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Specifies the less-than comparison function signature.

```elixir
@spec lt?(t(), t()) :: boolean()
```

--------------------------------

### Perform arithmetic operations

Source: https://hexdocs.pm/fastdecimal/index.html

Execute standard arithmetic operations with configurable precision and rounding modes.

```elixir
FastDecimal.add(a, b)
FastDecimal.sub(a, b)
FastDecimal.mult(a, b)
FastDecimal.div(a, b, precision: 28, rounding: :half_even)
                                  # Exact quotients short-circuit (~30 ns) and
                                  # return Decimal's ideal-exponent form: div(10, 2) == ~d"5"
FastDecimal.div_int(a, b)         # Truncated integer division
FastDecimal.div_rem(a, b)         # {quotient, remainder}
FastDecimal.rem(a, b)
FastDecimal.negate(a)
FastDecimal.abs(a)
FastDecimal.sqrt(a, precision: 28)  # Newton-Raphson
FastDecimal.round(a, places, mode)   # All 7 rounding modes
```

--------------------------------

### Define neg_inf specification

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Specifies the negative infinity sentinel function signature.

```elixir
@spec neg_inf() :: t()
```

--------------------------------

### Define inf specification

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Specifies the infinity sentinel function signature.

```elixir
@spec inf() :: t()
```

--------------------------------

### Cast input value

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Attempts to cast an input to a FastDecimal type, returning :ok or :error.

```elixir
@spec cast(input()) :: {:ok, FastDecimal.t()} | :error
```

--------------------------------

### Integer division

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Performs integer division on two inputs.

```elixir
@spec div_int(input(), input()) :: FastDecimal.t()
```

--------------------------------

### Define nan specification

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Specifies the NaN sentinel function signature.

```elixir
@spec nan() :: t()
```

--------------------------------

### Infinity value

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Returns the infinity value.

```elixir
@spec inf() :: FastDecimal.t()
```

--------------------------------

### Check greater than

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Checks if the first input is greater than the second.

```elixir
@spec gt?(input(), input()) :: boolean()
```

--------------------------------

### div_int(a, b)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Performs integer (truncated) division on two FastDecimal values.

```APIDOC
## div_int(a, b)

### Description
Performs integer (truncated) division. Like Kernel.div/2 for integers, it drops the fractional part, truncating toward zero. The result always has an exponent of 0.

### Signature
`@spec div_int(t(), t()) :: t()`

### Example
`FastDecimal.div_int(FastDecimal.new("10.5"), FastDecimal.new("3"))`
```

--------------------------------

### inf?(fast_decimal)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Returns true if the value is +∞ or -∞.

```APIDOC
## inf?(fast_decimal)

### Signature
`@spec inf?(t()) :: boolean()`
```

--------------------------------

### Multiply two values (alias)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Alias for mult/2.

```elixir
@spec multiply(input(), input()) :: FastDecimal.t()
```

--------------------------------

### cast(value)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Attempts to cast the input value to a FastDecimal type. Returns {:ok, t} on success or :error.

```APIDOC
## cast(value)

### Signature
`cast(input()) :: {:ok, FastDecimal.t()} | :error`
```

--------------------------------

### Arithmetic

Source: https://hexdocs.pm/fastdecimal/index.html

Mathematical operations supported by the library.

```APIDOC
## Arithmetic Operations

### Description
Standard arithmetic functions including add, sub, mult, div, div_int, div_rem, rem, negate, abs, sqrt, and round.

### Signatures
- `FastDecimal.add(a, b)`
- `FastDecimal.sub(a, b)`
- `FastDecimal.mult(a, b)`
- `FastDecimal.div(a, b, precision: 28, rounding: :half_even)`
- `FastDecimal.div_int(a, b)`
- `FastDecimal.div_rem(a, b)`
- `FastDecimal.rem(a, b)`
- `FastDecimal.negate(a)`
- `FastDecimal.abs(a)`
- `FastDecimal.sqrt(a, precision: 28)`
- `FastDecimal.round(a, places, mode)`
```

--------------------------------

### Cast input to FastDecimal

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Attempts to coerce various input types into a FastDecimal struct without raising errors.

```elixir
@spec cast(t() | integer() | binary() | Decimal.t() | float() | nil) ::
  {:ok, t()} | :error
```

--------------------------------

### zero?(fast_decimal)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Checks if a FastDecimal value is zero.

```APIDOC
## zero?(fast_decimal)

### Description
Checks if the provided FastDecimal value is equal to zero.

### Signature
`zero?(t()) :: boolean()`

### Parameters
- **fast_decimal** (t()) - Required - The FastDecimal value to check.

### Returns
- **boolean** - Returns true if the value is zero, otherwise false.
```

--------------------------------

### Calculate square root

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Computes the square root of a decimal value with optional configuration.

```elixir
@spec sqrt(
  input(),
  keyword()
) :: FastDecimal.t()
```

--------------------------------

### sigil_d(arg, modifiers)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Compile-time literal sigil for creating FastDecimal values.

```APIDOC
## sigil_d(arg, modifiers)

### Description
Compile-time literal sigil. `~d"1.23"` becomes a `%FastDecimal{}` at compile time, paying zero parse cost at runtime.
```

--------------------------------

### Calculate negation

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Returns the negated value of the input.

```elixir
@spec minus(input()) :: FastDecimal.t()
```

--------------------------------

### Normalize a FastDecimal

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Strips trailing zeros from the coefficient and adjusts the exponent accordingly.

```elixir
@spec normalize(t()) :: t()
```

--------------------------------

### div_rem(arg1, arg2)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Returns the quotient and remainder of a division operation.

```APIDOC
## div_rem(arg1, arg2)

### Description
Returns a tuple {quotient, remainder} such that a == quotient * b + remainder. The quotient is computed using div_int/2.

### Signature
`@spec div_rem(t(), t()) :: {t(), t()}`

### Example
`FastDecimal.div_rem(FastDecimal.new("10"), FastDecimal.new("3"))`
```

--------------------------------

### Find minimum of two values

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Returns the smaller of two decimal values.

```elixir
@spec min(input(), input()) :: FastDecimal.t()
```

--------------------------------

### Normalize decimal

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Normalizes the decimal representation.

```elixir
@spec normalize(input()) :: FastDecimal.t()
```

--------------------------------

### Define inf? specification

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Specifies the infinity check function signature.

```elixir
@spec inf?(t()) :: boolean()
```

--------------------------------

### finite?(fast_decimal)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Checks if a FastDecimal value is finite.

```APIDOC
## finite?(fast_decimal)

### Description
Returns true if the value is a finite number (not NaN, not infinity).

### Signature
`@spec finite?(t()) :: boolean()`
```

--------------------------------

### mult(a, b)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Multiplies two decimals.

```APIDOC
## mult(a, b)

### Signature
`@spec mult(t(), t()) :: t()`
```

--------------------------------

### Define nan? specification

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Specifies the NaN check function signature.

```elixir
@spec nan?(t()) :: boolean()
```

--------------------------------

### Define gt? specification

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Specifies the greater-than comparison function signature.

```elixir
@spec gt?(t(), t()) :: boolean()
```

--------------------------------

### Reduce decimal

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Reduces the decimal representation.

```elixir
@spec reduce(input()) :: FastDecimal.t()
```

--------------------------------

### Check if negative

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Returns true if the decimal is negative.

```elixir
@spec negative?(t()) :: boolean()
```

--------------------------------

### Check if value is negative

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Determines if the input is less than zero.

```elixir
@spec negative?(input()) :: boolean()
```

--------------------------------

### Check for finite values with finite?/1

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Returns true if the provided decimal is a finite number, excluding NaN and infinity.

```elixir
@spec finite?(t()) :: boolean()
```

--------------------------------

### Check if positive

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Returns true if the decimal is positive.

```elixir
@spec positive?(t()) :: boolean()
```

--------------------------------

### normalize(d)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Strips trailing zeros from the coefficient, raising the exponent.

```APIDOC
## normalize(t())

### Description
Strip trailing zeros from the coefficient, raising the exponent. `~d"1.10"` (coef=110, exp=-2) becomes `~d"1.1"` (coef=11, exp=-1).

### Signature
`@spec normalize(t()) :: t()`
```

--------------------------------

### Multiply two values

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Multiplies two decimal inputs.

```elixir
@spec mult(input(), input()) :: FastDecimal.t()
```

--------------------------------

### Calculate absolute value

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Returns the absolute value of the input.

```elixir
@spec abs(input()) :: FastDecimal.t()
```

--------------------------------

### max(a, b)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Returns the larger of two decimals.

```APIDOC
## max(a, b)

### Description
The larger of two decimals. If exactly one operand is NaN, the number is returned (IEEE 754 maxNum semantics, matching Decimal.max/2); NaN is returned only when both operands are NaN.

### Signature
`@spec max(t(), t()) :: t()`
```

--------------------------------

### round(a, places, mode)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Rounds a decimal value to a specified number of decimal places using a defined rounding mode.

```APIDOC
## round(a, places, mode)

### Description
Rounds the input decimal to the specified number of places using the provided rounding mode.

### Signature
`round(input(), integer(), FastDecimal.rounding_mode()) :: FastDecimal.t()`
```

--------------------------------

### negative?(fast_decimal)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Checks if the given FastDecimal is negative.

```APIDOC
## negative?(t())

### Description
Checks if the given FastDecimal is negative.

### Signature
`@spec negative?(t()) :: boolean()`
```

--------------------------------

### Define mult specification

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Specifies the multiplication function signature.

```elixir
@spec mult(t(), t()) :: t()
```

--------------------------------

### Create NaN value

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Returns a Not-a-Number decimal value.

```elixir
@spec nan() :: FastDecimal.t()
```

--------------------------------

### sub(a, b)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Compat.html

Subtracts one decimal value from another.

```APIDOC
## sub(a, b)

### Description
Subtracts the second decimal value from the first.

### Signature
`sub(input(), input()) :: FastDecimal.t()`
```

--------------------------------

### rem(a, b)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Calculates the remainder of decimal division.

```APIDOC
## rem(t(), t())

### Description
Remainder of decimal division (same sign as the dividend).

### Signature
`@spec rem(t(), t()) :: t()`
```

--------------------------------

### positive?(fast_decimal)

Source: https://hexdocs.pm/fastdecimal/FastDecimal.html

Checks if the given FastDecimal is positive.

```APIDOC
## positive?(t())

### Description
Checks if the given FastDecimal is positive.

### Signature
`@spec positive?(t()) :: boolean()`
```

--------------------------------

### Define an Ecto schema with FastDecimal

Source: https://hexdocs.pm/fastdecimal/FastDecimal.Ecto.Type.html

Use FastDecimal.Ecto.Type as the field type within an Ecto schema to map database numeric columns to FastDecimal structs.

```elixir
defmodule MyApp.Invoice do
  use Ecto.Schema

  schema "invoices" do
    field :total, FastDecimal.Ecto.Type
  end
end
```
Tokens:
Raw