712 lines
18 KiB
Erlang
712 lines
18 KiB
Erlang
-module(gleam@float).
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-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
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-define(FILEPATH, "src/gleam/float.gleam").
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-export([parse/1, to_string/1, max/2, min/2, clamp/3, compare/2, absolute_value/1, loosely_compare/3, loosely_equals/3, ceiling/1, floor/1, negate/1, round/1, truncate/1, to_precision/2, power/2, square_root/1, sum/1, product/1, random/0, modulo/2, divide/2, add/2, multiply/2, subtract/2, logarithm/1, exponential/1]).
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-if(?OTP_RELEASE >= 27).
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-define(MODULEDOC(Str), -moduledoc(Str)).
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-define(DOC(Str), -doc(Str)).
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-else.
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-define(MODULEDOC(Str), -compile([])).
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-define(DOC(Str), -compile([])).
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-endif.
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?MODULEDOC(
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" Functions for working with floats.\n"
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"\n"
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" ## Float representation\n"
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"\n"
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" Floats are represented as 64 bit floating point numbers on both the Erlang\n"
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" and JavaScript runtimes. The floating point behaviour is native to their\n"
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" respective runtimes, so their exact behaviour will be slightly different on\n"
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" the two runtimes.\n"
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"\n"
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" ### Infinity and NaN\n"
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"\n"
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" Under the JavaScript runtime, exceeding the maximum (or minimum)\n"
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" representable value for a floating point value will result in Infinity (or\n"
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" -Infinity). Should you try to divide two infinities you will get NaN as a\n"
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" result.\n"
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"\n"
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" When running on BEAM, exceeding the maximum (or minimum) representable\n"
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" value for a floating point value will raise an error.\n"
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"\n"
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" ## Division by zero\n"
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"\n"
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" Gleam runs on the Erlang virtual machine, which does not follow the IEEE\n"
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" 754 standard for floating point arithmetic and does not have an `Infinity`\n"
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" value. In Erlang division by zero results in a crash, however Gleam does\n"
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" not have partial functions and operators in core so instead division by zero\n"
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" returns zero, a behaviour taken from Pony, Coq, and Lean.\n"
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"\n"
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" This may seem unexpected at first, but it is no less mathematically valid\n"
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" than crashing or returning a special value. Division by zero is undefined\n"
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" in mathematics.\n"
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).
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-file("src/gleam/float.gleam", 49).
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?DOC(
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" Attempts to parse a string as a `Float`, returning `Error(Nil)` if it was\n"
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" not possible.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert parse(\"2.3\") == Ok(2.3)\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert parse(\"ABC\") == Error(Nil)\n"
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" ```\n"
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).
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-spec parse(binary()) -> {ok, float()} | {error, nil}.
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parse(String) ->
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gleam_stdlib:parse_float(String).
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-file("src/gleam/float.gleam", 61).
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?DOC(
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" Returns the string representation of the provided `Float`.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert to_string(2.3) == \"2.3\"\n"
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" ```\n"
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).
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-spec to_string(float()) -> binary().
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to_string(X) ->
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gleam_stdlib:float_to_string(X).
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-file("src/gleam/float.gleam", 192).
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?DOC(
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" Compares two `Float`s, returning the larger of the two.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert max(2.0, 2.3) == 2.3\n"
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" ```\n"
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).
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-spec max(float(), float()) -> float().
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max(A, B) ->
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case A > B of
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true ->
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A;
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false ->
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B
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end.
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-file("src/gleam/float.gleam", 177).
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?DOC(
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" Compares two `Float`s, returning the smaller of the two.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert min(2.0, 2.3) == 2.0\n"
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" ```\n"
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).
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-spec min(float(), float()) -> float().
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min(A, B) ->
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case A < B of
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true ->
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A;
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false ->
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B
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end.
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-file("src/gleam/float.gleam", 80).
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?DOC(
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" Restricts a float between two bounds.\n"
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"\n"
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" Note: If the `min` argument is larger than the `max` argument then they\n"
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" will be swapped, so the minimum bound is always lower than the maximum\n"
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" bound.\n"
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"\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert clamp(1.2, min: 1.4, max: 1.6) == 1.4\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert clamp(1.2, min: 1.4, max: 0.6) == 1.2\n"
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" ```\n"
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).
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-spec clamp(float(), float(), float()) -> float().
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clamp(X, Min_bound, Max_bound) ->
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case Min_bound >= Max_bound of
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true ->
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_pipe = X,
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_pipe@1 = min(_pipe, Min_bound),
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max(_pipe@1, Max_bound);
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false ->
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_pipe@2 = X,
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_pipe@3 = min(_pipe@2, Max_bound),
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max(_pipe@3, Min_bound)
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end.
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-file("src/gleam/float.gleam", 100).
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?DOC(
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" Compares two `Float`s, returning an `Order`:\n"
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" `Lt` for lower than, `Eq` for equals, or `Gt` for greater than.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert compare(2.0, 2.3) == Lt\n"
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" ```\n"
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"\n"
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" To handle\n"
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" [Floating Point Imprecision](https://en.wikipedia.org/wiki/Floating-point_arithmetic#Accuracy_problems)\n"
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" you may use [`loosely_compare`](#loosely_compare) instead.\n"
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).
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-spec compare(float(), float()) -> gleam@order:order().
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compare(A, B) ->
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case A =:= B of
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true ->
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eq;
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false ->
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case A < B of
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true ->
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lt;
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false ->
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gt
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end
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end.
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-file("src/gleam/float.gleam", 302).
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?DOC(
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" Returns the absolute value of the input as a `Float`.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert absolute_value(-12.5) == 12.5\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert absolute_value(10.2) == 10.2\n"
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" ```\n"
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).
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-spec absolute_value(float()) -> float().
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absolute_value(X) ->
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case X >= +0.0 of
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true ->
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X;
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false ->
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+0.0 - X
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end.
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-file("src/gleam/float.gleam", 129).
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?DOC(
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" Compares two `Float`s within a tolerance, returning an `Order`:\n"
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" `Lt` for lower than, `Eq` for equals, or `Gt` for greater than.\n"
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"\n"
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" This function allows Float comparison while handling\n"
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" [Floating Point Imprecision](https://en.wikipedia.org/wiki/Floating-point_arithmetic#Accuracy_problems).\n"
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"\n"
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" Notice: For `Float`s the tolerance won't be exact:\n"
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" `5.3 - 5.0` is not exactly `0.3`.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert loosely_compare(5.0, with: 5.3, tolerating: 0.5) == Eq\n"
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" ```\n"
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"\n"
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" If you want to check only for equality you may use\n"
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" [`loosely_equals`](#loosely_equals) instead.\n"
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).
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-spec loosely_compare(float(), float(), float()) -> gleam@order:order().
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loosely_compare(A, B, Tolerance) ->
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Difference = absolute_value(A - B),
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case Difference =< Tolerance of
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true ->
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eq;
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false ->
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compare(A, B)
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end.
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-file("src/gleam/float.gleam", 160).
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?DOC(
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" Checks for equality of two `Float`s within a tolerance,\n"
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" returning a `Bool`.\n"
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"\n"
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" This function allows Float comparison while handling\n"
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" [Floating Point Imprecision](https://en.wikipedia.org/wiki/Floating-point_arithmetic#Accuracy_problems).\n"
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"\n"
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" Notice: For `Float`s the tolerance won't be exact:\n"
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" `5.3 - 5.0` is not exactly `0.3`.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert loosely_equals(5.0, with: 5.3, tolerating: 0.5)\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert !loosely_equals(5.0, with: 5.1, tolerating: 0.1)\n"
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" ```\n"
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).
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-spec loosely_equals(float(), float(), float()) -> boolean().
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loosely_equals(A, B, Tolerance) ->
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Difference = absolute_value(A - B),
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Difference =< Tolerance.
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-file("src/gleam/float.gleam", 209).
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?DOC(
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" Rounds the value to the next highest whole number as a `Float`.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert ceiling(2.3) == 3.0\n"
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" ```\n"
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).
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-spec ceiling(float()) -> float().
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ceiling(X) ->
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math:ceil(X).
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-file("src/gleam/float.gleam", 221).
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?DOC(
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" Rounds the value to the next lowest whole number as a `Float`.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert floor(2.3) == 2.0\n"
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" ```\n"
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).
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-spec floor(float()) -> float().
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floor(X) ->
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math:floor(X).
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-file("src/gleam/float.gleam", 376).
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?DOC(
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" Returns the negative of the value provided.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert negate(1.0) == -1.0\n"
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" ```\n"
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).
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-spec negate(float()) -> float().
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negate(X) ->
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-1.0 * X.
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-file("src/gleam/float.gleam", 236).
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?DOC(
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" Rounds the value to the nearest whole number as an `Int`.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert round(2.3) == 2\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert round(2.5) == 3\n"
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" ```\n"
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).
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-spec round(float()) -> integer().
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round(X) ->
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erlang:round(X).
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-file("src/gleam/float.gleam", 256).
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?DOC(
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" Returns the value as an `Int`, truncating all decimal digits.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert truncate(2.4343434847383438) == 2\n"
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" ```\n"
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).
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-spec truncate(float()) -> integer().
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truncate(X) ->
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erlang:trunc(X).
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-file("src/gleam/float.gleam", 273).
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?DOC(
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" Converts the value to a given precision as a `Float`.\n"
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" The precision is the number of allowed decimal places.\n"
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" Negative precisions are allowed and force rounding\n"
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" to the nearest tenth, hundredth, thousandth etc.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert to_precision(2.43434348473, 2) == 2.43\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert to_precision(547890.453444, -3) == 548000.0\n"
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" ```\n"
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).
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-spec to_precision(float(), integer()) -> float().
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to_precision(X, Precision) ->
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case Precision =< 0 of
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true ->
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Factor = math:pow(10.0, erlang:float(- Precision)),
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erlang:float(erlang:round(case Factor of
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+0.0 -> +0.0;
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-0.0 -> -0.0;
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Gleam@denominator -> X / Gleam@denominator
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end)) * Factor;
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false ->
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Factor@1 = math:pow(10.0, erlang:float(Precision)),
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case Factor@1 of
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+0.0 -> +0.0;
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-0.0 -> -0.0;
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Gleam@denominator@1 -> erlang:float(erlang:round(X * Factor@1))
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/ Gleam@denominator@1
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end
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end.
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-file("src/gleam/float.gleam", 334).
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?DOC(
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" Returns the result of the base being raised to the power of the\n"
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" exponent, as a `Float`.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert power(2.0, -1.0) == Ok(0.5)\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert power(2.0, 2.0) == Ok(4.0)\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert power(8.0, 1.5) == Ok(22.627416997969522)\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert 4.0 |> power(of: 2.0) == Ok(16.0)\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert power(-1.0, 0.5) == Error(Nil)\n"
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" ```\n"
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).
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-spec power(float(), float()) -> {ok, float()} | {error, nil}.
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power(Base, Exponent) ->
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Fractional = (math:ceil(Exponent) - Exponent) > +0.0,
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case ((Base < +0.0) andalso Fractional) orelse ((Base =:= +0.0) andalso (Exponent
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< +0.0)) of
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true ->
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{error, nil};
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false ->
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{ok, math:pow(Base, Exponent)}
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end.
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-file("src/gleam/float.gleam", 364).
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?DOC(
|
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" Returns the square root of the input as a `Float`.\n"
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"\n"
|
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" ## Examples\n"
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"\n"
|
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" ```gleam\n"
|
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" assert square_root(4.0) == Ok(2.0)\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert square_root(-16.0) == Error(Nil)\n"
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" ```\n"
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).
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-spec square_root(float()) -> {ok, float()} | {error, nil}.
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square_root(X) ->
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power(X, 0.5).
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-file("src/gleam/float.gleam", 392).
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-spec sum_loop(list(float()), float()) -> float().
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sum_loop(Numbers, Initial) ->
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case Numbers of
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[First | Rest] ->
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sum_loop(Rest, First + Initial);
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[] ->
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Initial
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end.
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-file("src/gleam/float.gleam", 388).
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?DOC(
|
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" Sums a list of `Float`s.\n"
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"\n"
|
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" ## Example\n"
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"\n"
|
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" ```gleam\n"
|
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" assert sum([1.0, 2.2, 3.3]) == 6.5\n"
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" ```\n"
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).
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-spec sum(list(float())) -> float().
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sum(Numbers) ->
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sum_loop(Numbers, +0.0).
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-file("src/gleam/float.gleam", 411).
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-spec product_loop(list(float()), float()) -> float().
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product_loop(Numbers, Initial) ->
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case Numbers of
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[First | Rest] ->
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product_loop(Rest, First * Initial);
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[] ->
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Initial
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end.
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-file("src/gleam/float.gleam", 407).
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?DOC(
|
|
" Multiplies a list of `Float`s and returns the product.\n"
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"\n"
|
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" ## Example\n"
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"\n"
|
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" ```gleam\n"
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" assert product([2.5, 3.2, 4.2]) == 33.6\n"
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" ```\n"
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).
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-spec product(list(float())) -> float().
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product(Numbers) ->
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product_loop(Numbers, 1.0).
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-file("src/gleam/float.gleam", 433).
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?DOC(
|
|
" Generates a random float between the given zero (inclusive) and one\n"
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|
" (exclusive).\n"
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"\n"
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|
" On Erlang this updates the random state in the process dictionary.\n"
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|
" See: <https://www.erlang.org/doc/man/rand.html#uniform-0>\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" random()\n"
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" // -> 0.646355926896028\n"
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" ```\n"
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).
|
|
-spec random() -> float().
|
|
random() ->
|
|
rand:uniform().
|
|
|
|
-file("src/gleam/float.gleam", 460).
|
|
?DOC(
|
|
" Computes the modulo of a float division of inputs as a `Result`.\n"
|
|
"\n"
|
|
" Returns division of the inputs as a `Result`: If the given divisor equals\n"
|
|
" `0`, this function returns an `Error`.\n"
|
|
"\n"
|
|
" The computed value will always have the same sign as the `divisor`.\n"
|
|
"\n"
|
|
" ## Examples\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert modulo(13.3, by: 3.3) == Ok(0.1)\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert modulo(-13.3, by: 3.3) == Ok(3.2)\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert modulo(13.3, by: -3.3) == Ok(-3.2)\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert modulo(-13.3, by: -3.3) == Ok(-0.1)\n"
|
|
" ```\n"
|
|
).
|
|
-spec modulo(float(), float()) -> {ok, float()} | {error, nil}.
|
|
modulo(Dividend, Divisor) ->
|
|
case Divisor of
|
|
+0.0 ->
|
|
{error, nil};
|
|
|
|
_ ->
|
|
{ok, Dividend - (math:floor(case Divisor of
|
|
+0.0 -> +0.0;
|
|
-0.0 -> -0.0;
|
|
Gleam@denominator -> Dividend / Gleam@denominator
|
|
end) * Divisor)}
|
|
end.
|
|
|
|
-file("src/gleam/float.gleam", 479).
|
|
?DOC(
|
|
" Returns division of the inputs as a `Result`.\n"
|
|
"\n"
|
|
" ## Examples\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert divide(0.0, 1.0) == Ok(0.0)\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert divide(1.0, 0.0) == Error(Nil)\n"
|
|
" ```\n"
|
|
).
|
|
-spec divide(float(), float()) -> {ok, float()} | {error, nil}.
|
|
divide(A, B) ->
|
|
case B of
|
|
+0.0 ->
|
|
{error, nil};
|
|
|
|
B@1 ->
|
|
{ok, case B@1 of
|
|
+0.0 -> +0.0;
|
|
-0.0 -> -0.0;
|
|
Gleam@denominator -> A / Gleam@denominator
|
|
end}
|
|
end.
|
|
|
|
-file("src/gleam/float.gleam", 507).
|
|
?DOC(
|
|
" Adds two floats together.\n"
|
|
"\n"
|
|
" It's the function equivalent of the `+.` operator.\n"
|
|
" This function is useful in higher order functions or pipes.\n"
|
|
"\n"
|
|
" ## Examples\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert add(1.0, 2.0) == 3.0\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" import gleam/list\n"
|
|
"\n"
|
|
" assert list.fold([1.0, 2.0, 3.0], 0.0, add) == 6.0\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert 3.0 |> add(2.0) == 5.0\n"
|
|
" ```\n"
|
|
).
|
|
-spec add(float(), float()) -> float().
|
|
add(A, B) ->
|
|
A + B.
|
|
|
|
-file("src/gleam/float.gleam", 532).
|
|
?DOC(
|
|
" Multiplies two floats together.\n"
|
|
"\n"
|
|
" It's the function equivalent of the `*.` operator.\n"
|
|
" This function is useful in higher order functions or pipes.\n"
|
|
"\n"
|
|
" ## Examples\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert multiply(2.0, 4.0) == 8.0\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" import gleam/list\n"
|
|
"\n"
|
|
" assert list.fold([2.0, 3.0, 4.0], 1.0, multiply) == 24.0\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert 3.0 |> multiply(2.0) == 6.0\n"
|
|
" ```\n"
|
|
).
|
|
-spec multiply(float(), float()) -> float().
|
|
multiply(A, B) ->
|
|
A * B.
|
|
|
|
-file("src/gleam/float.gleam", 561).
|
|
?DOC(
|
|
" Subtracts one float from another.\n"
|
|
"\n"
|
|
" It's the function equivalent of the `-.` operator.\n"
|
|
" This function is useful in higher order functions or pipes.\n"
|
|
"\n"
|
|
" ## Examples\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert subtract(3.0, 1.0) == 2.0\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" import gleam/list\n"
|
|
"\n"
|
|
" assert list.fold([1.0, 2.0, 3.0], 10.0, subtract) == 4.0\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert 3.0 |> subtract(_, 2.0) == 1.0\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert 3.0 |> subtract(2.0, _) == -1.0\n"
|
|
" ```\n"
|
|
).
|
|
-spec subtract(float(), float()) -> float().
|
|
subtract(A, B) ->
|
|
A - B.
|
|
|
|
-file("src/gleam/float.gleam", 586).
|
|
?DOC(
|
|
" Returns the natural logarithm (base e) of the given `Float` as a `Result`. If the\n"
|
|
" input is less than or equal to 0, returns `Error(Nil)`.\n"
|
|
"\n"
|
|
" ## Examples\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert logarithm(1.0) == Ok(0.0)\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert logarithm(2.718281828459045) == Ok(1.0)\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert logarithm(0.0) == Error(Nil)\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert logarithm(-1.0) == Error(Nil)\n"
|
|
" ```\n"
|
|
).
|
|
-spec logarithm(float()) -> {ok, float()} | {error, nil}.
|
|
logarithm(X) ->
|
|
case X =< +0.0 of
|
|
true ->
|
|
{error, nil};
|
|
|
|
false ->
|
|
{ok, math:log(X)}
|
|
end.
|
|
|
|
-file("src/gleam/float.gleam", 621).
|
|
?DOC(
|
|
" Returns e (Euler's number) raised to the power of the given exponent, as\n"
|
|
" a `Float`.\n"
|
|
"\n"
|
|
" ## Examples\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert exponential(0.0) == 1.0\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert exponential(1.0) == 2.718281828459045\n"
|
|
" ```\n"
|
|
"\n"
|
|
" ```gleam\n"
|
|
" assert exponential(-1.0) == 0.36787944117144233\n"
|
|
" ```\n"
|
|
).
|
|
-spec exponential(float()) -> float().
|
|
exponential(X) ->
|
|
math:exp(X).
|