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Alias std.numeric.CustomFloat

Allows user code to define custom floating-point formats. These formats are for storage only; all operations on them are performed by first implicitly extracting them to real first. After the operation is completed the result can be stored in a custom floating-point value via assignment.

alias CustomFloat(uint bits) = CustomFloat!(CustomFloatParams!bits);
alias CustomFloat(uint precision, uint exponentWidth, CustomFloatFlags flags = CustomFloatFlags.ieee) = CustomFloat!(CustomFloatParams!(precision,exponentWidth,flags));
struct CustomFloat(uint precision, uint exponentWidth, CustomFloatFlags flags, uint bias)
  
if (isCorrectCustomFloat(precision, exponentWidth, flags));

Alias CustomFloat

Alias CustomFloat

Struct CustomFloat

Constructors

NameDescription
this (input) Initialize from any real compatible type.

Properties

NameTypeDescription
dig[get] size_t
epsilon[get] CustomFloat
get[get] FFetches the stored value either as a float, double or real.
im[get] CustomFloat
infinity[get] CustomFloat
max[get] CustomFloat
max_10_exp[get] int
min_10_exp[get] int
min_normal[get] CustomFloat
nan[get] CustomFloat
re[get] CustomFloat

Methods

NameDescription
opAssign (input) Self assignment
opAssign (input) Assigns from any real compatible type.
opBinary (b) Convert the CustomFloat to a real and perform the relevant operator on the result
opBinaryRight (a) Convert the CustomFloat to a real and perform the relevant operator on the result
opCmp (b) Convert the CustomFloat to a real and perform the relevant operator on the result
opOpAssign (b) Convert the CustomFloat to a real and perform the relevant operator on the result
opUnary () Convert the CustomFloat to a real and perform the relevant operator on the result

Aliases

NameDescription
opCast Fetches the stored value either as a float, double or real.

Templates

NameDescription
toString Convert the CustomFloat to a real and perform the relevant operator on the result

Example

import std.math.trigonometry : sin, cos;

// Define a 16-bit floating point values
CustomFloat!16                                x;     // Using the number of bits
CustomFloat!(10, 5)                           y;     // Using the precision and exponent width
CustomFloat!(10, 5,CustomFloatFlags.ieee)     z;     // Using the precision, exponent width and format flags
CustomFloat!(10, 5,CustomFloatFlags.ieee, 15) w;     // Using the precision, exponent width, format flags and exponent offset bias

// Use the 16-bit floats mostly like normal numbers
w = x*y - 1;

// Functions calls require conversion
z = sin(+x)           + cos(+y);                     // Use unary plus to concisely convert to a real
z = sin(x.get!float)  + cos(y.get!float);            // Or use get!T
z = sin(cast(float) x) + cos(cast(float) y);           // Or use cast(T) to explicitly convert

// Define a 8-bit custom float for storing probabilities
alias Probability = CustomFloat!(4, 4, CustomFloatFlags.ieee^CustomFloatFlags.probability^CustomFloatFlags.signed );
auto p = Probability(0.5);

Authors

Andrei Alexandrescu, Don Clugston, Robert Jacques, Ilya Yaroshenko

License

Boost License 1.0.