Data Streams Ex
v1.2.2

View Source Datadog.Sketch.IndexMapping behaviour (Data Streams Ex v1.2.2)

Basic module for handling various index mapping algorithms. All functions in this module proxy to the respective index mapping implementation module.

Summary

Types

t()

A general struct that has index mapping data. Every index mapping implementation must contain this data.

Callbacks

equals(t, t)

Checks if an index mapping matches another index mapping.

index(t, float)

Returns value after mapping.

lower_bound(t, integer)

Returns the lower bound the mapping can contain.

relative_accuracy(t)

Returns the relative accuracy of the mapping.

to_proto(t)

Returns a Protobuf-able struct for the index mapping. Used for sending data to Datadog.

value(t, integer)

Takes a mapped value and returns the original value within the set accuracy.

Functions

equals(self, other)

Checks if an index mapping matches another index mapping.

index(self, value)

Returns value after mapping.

lower_bound(self, index)

Returns the lower bound the mapping can contain.

relative_accuracy(self)

Returns the lower bound the mapping can contain.

to_proto(self)

Returns a Protobuf-able struct for the index mapping. Used for sending data to Datadog.

value(self, index)

Takes a mapped value and returns the original value within the set accuracy.

within_tolerance(x, y, tolerance)

Checks if the two values are within the tolerance given.

Types

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t()

View Source 
@type t() :: %{
  __struct__: module(),
  gamma: float(),
  index_offset: float(),
  multiplier: float()
}

A general struct that has index mapping data. Every index mapping implementation must contain this data.

Callbacks

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equals(t, t)

View Source 
@callback equals(t(), t()) :: boolean()

Checks if an index mapping matches another index mapping.

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index(t, float)

View Source 
@callback index(t(), float()) :: integer()

Returns value after mapping.

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lower_bound(t, integer)

View Source 
@callback lower_bound(t(), integer()) :: float()

Returns the lower bound the mapping can contain.

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relative_accuracy(t)

View Source 
@callback relative_accuracy(t()) :: float()

Returns the relative accuracy of the mapping.

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to_proto(t)

View Source 
@callback to_proto(t()) :: struct()

Returns a Protobuf-able struct for the index mapping. Used for sending data to Datadog.

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value(t, integer)

View Source 
@callback value(t(), integer()) :: float()

Takes a mapped value and returns the original value within the set accuracy.

Functions

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equals(self, other)

View Source 
@spec equals(t(), t()) :: boolean()

Checks if an index mapping matches another index mapping.

iex> implementation_one = IndexMapping.Logarithmic.new(0.0000000000001)
...> implementation_two = IndexMapping.Logarithmic.new(0.0000000000002)
...> IndexMapping.equals(implementation_one, implementation_two)
true

iex> implementation_one = IndexMapping.Logarithmic.new(0.01)
...> implementation_two = IndexMapping.Logarithmic.new(0.00001)
...> IndexMapping.equals(implementation_one, implementation_two)
false
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index(self, value)

View Source 
@spec index(t(), float()) :: integer()

Returns value after mapping.

iex> index_mapping = IndexMapping.Logarithmic.new(0.01)
...> IndexMapping.index(index_mapping, 115)
237

iex> index_mapping = IndexMapping.Logarithmic.new(0.001)
...> IndexMapping.index(index_mapping, 12345678901234567890)
21979
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lower_bound(self, index)

View Source 
@spec lower_bound(t(), integer()) :: float()

Returns the lower bound the mapping can contain.

iex> index_mapping = IndexMapping.Logarithmic.new(0.01)
...> IndexMapping.lower_bound(index_mapping, 0)
1.0

iex> index_mapping = IndexMapping.Logarithmic.new(0.01)
...> IndexMapping.lower_bound(index_mapping, 10)
1.2214109013609646
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relative_accuracy(self)

View Source 
@spec relative_accuracy(t()) :: float()

Returns the lower bound the mapping can contain.

iex> index_mapping = IndexMapping.Logarithmic.new(0.01)
...> IndexMapping.relative_accuracy(index_mapping)
0.009999999999999898
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to_proto(self)

View Source 
@spec to_proto(t()) :: struct()

Returns a Protobuf-able struct for the index mapping. Used for sending data to Datadog.

iex> index_mapping = IndexMapping.Logarithmic.new(0.01)
...> IndexMapping.to_proto(index_mapping)
%Datadog.Sketch.Protobuf.IndexMapping{gamma: 1.02020202020202, interpolation: :NONE}
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value(self, index)

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@spec value(t(), integer()) :: float()

Takes a mapped value and returns the original value within the set accuracy.

iex> index_mapping = IndexMapping.Logarithmic.new(0.01)
...> IndexMapping.value(index_mapping, 237)
115.59680764552533

iex> index_mapping = IndexMapping.Logarithmic.new(0.001)
...> IndexMapping.value(index_mapping, 21979)
1.23355147396003e19
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within_tolerance(x, y, tolerance)

View Source 
@spec within_tolerance(float(), float(), float()) :: bool()

Checks if the two values are within the tolerance given.

Examples 

iex> IndexMapping.within_tolerance(90, 134, 50)
true

iex> IndexMapping.within_tolerance(0.00128, 0.00864, 0.01)
false