rspec/rules/S1244/csharp/rule.adoc

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Floating point math is imprecise because of the challenges of storing such values in a binary representation. Even worse, floating point math is not associative; push a ``float`` or a ``double`` through a series of simple mathematical operations and the answer will be different based on the order of those operation because of the rounding that takes place at each step.
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Even simple floating point assignments are not simple:
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----
float f = 0.100000001f; // 0.1
double d = 0.10000000000000001; // 0.1
----
(Results will vary based on compiler and compiler settings)
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Therefore, the use of the equality (``==``) and inequality (``!=``) operators on ``float`` or ``double`` values is almost always an error.
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This rule checks for the use of direct and indirect equality/inequality tests on floats and doubles.
== Noncompliant Code Example
----
float myNumber = 3.146f;
if ( myNumber == 3.146f ) //Noncompliant. Because of floating point imprecision, this will be false
{
// ...
}
if (myNumber <= 3.146f && mNumber >= 3.146f) // Noncompliant indirect equality test
{
// ...
}
if (myNumber < 4 || myNumber > 4) // Noncompliant indirect inequality test
{
// ...
}
----