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	std.math.traits
This is a submodule of std.math.
It contains several functions for introspection on numerical values.
License: 
Authors: 
Walter Bright, Don Clugston,
           Conversion of CEPHES math library to D by Iain Buclaw and David Nadlinger
Source std/math/traits.d
- pure nothrow @nogc @trusted boolisNaN(X)(Xx)
 if (isFloatingPoint!X);
- Determines if x is NaN.Parameters:X xa floating point number. Returns:true if x is Nan.Examples:assert( isNaN(float.init)); assert( isNaN(-double.init)); assert( isNaN(real.nan)); assert( isNaN(-real.nan)); assert(!isNaN(cast(float) 53.6)); assert(!isNaN(cast(real)-53.6)); 
- pure nothrow @nogc @trusted boolisFinite(X)(Xx);
- Determines if x is finite.Parameters:X xa floating point number. Returns:true if x is finite.Examples:assert( isFinite(1.23f)); assert( isFinite(float.max)); assert( isFinite(float.min_normal)); assert(!isFinite(float.nan)); assert(!isFinite(float.infinity)); 
- pure nothrow @nogc @trusted boolisNormal(X)(Xx);
- Determines if x is normalized.A normalized number must not be zero, subnormal, infinite nor NAN.Parameters:X xa floating point number. Returns:true if x is normalized.Examples:float f = 3; double d = 500; real e = 10e+48; assert(isNormal(f)); assert(isNormal(d)); assert(isNormal(e)); f = d = e = 0; assert(!isNormal(f)); assert(!isNormal(d)); assert(!isNormal(e)); assert(!isNormal(real.infinity)); assert(isNormal(-real.max)); assert(!isNormal(real.min_normal/4)); 
- pure nothrow @nogc @trusted boolisSubnormal(X)(Xx);
- Determines if x is subnormal.Subnormals (also known as "denormal number"), have a 0 exponent and a 0 most significant mantissa bit.Parameters:X xa floating point number. Returns:true if x is a denormal number.Examples:import std.meta : AliasSeq; static foreach (T; AliasSeq!(float, double, real)) {{ T f; for (f = 1.0; !isSubnormal(f); f /= 2) assert(f != 0); }} 
- pure nothrow @nogc @trusted boolisInfinity(X)(Xx)
 if (isFloatingPoint!X);
- Determines if x is ±∞.Parameters:X xa floating point number. Returns:true if x is ±∞.Examples:assert(!isInfinity(float.init)); assert(!isInfinity(-float.init)); assert(!isInfinity(float.nan)); assert(!isInfinity(-float.nan)); assert(isInfinity(float.infinity)); assert(isInfinity(-float.infinity)); assert(isInfinity(-1.0f / 0.0f)); 
- pure nothrow @nogc @trusted boolisIdentical(realx, realy);
- Is the binary representation of x identical to y?Examples:// We're forcing the CTFE to run by assigning the result of the function to an enum enum test1 = isIdentical(1.0,1.0); enum test2 = isIdentical(real.nan,real.nan); enum test3 = isIdentical(real.infinity, real.infinity); enum test4 = isIdentical(real.infinity, real.infinity); enum test5 = isIdentical(0.0, 0.0); assert(test1); assert(test2); assert(test3); assert(test4); assert(test5); enum test6 = !isIdentical(0.0, -0.0); enum test7 = !isIdentical(real.nan, -real.nan); enum test8 = !isIdentical(real.infinity, -real.infinity); assert(test6); assert(test7); assert(test8); 
- pure nothrow @nogc @trusted intsignbit(X)(Xx);
- Return 1 if sign bit of e is set, 0 if not.Examples:assert(!signbit(float.nan)); assert(signbit(-float.nan)); assert(!signbit(168.1234f)); assert(signbit(-168.1234f)); assert(!signbit(0.0f)); assert(signbit(-0.0f)); assert(signbit(-float.max)); assert(!signbit(float.max)); assert(!signbit(double.nan)); assert(signbit(-double.nan)); assert(!signbit(168.1234)); assert(signbit(-168.1234)); assert(!signbit(0.0)); assert(signbit(-0.0)); assert(signbit(-double.max)); assert(!signbit(double.max)); assert(!signbit(real.nan)); assert(signbit(-real.nan)); assert(!signbit(168.1234L)); assert(signbit(-168.1234L)); assert(!signbit(0.0L)); assert(signbit(-0.0L)); assert(signbit(-real.max)); assert(!signbit(real.max)); 
- pure nothrow @nogc @trusted Rcopysign(R, X)(Rto, Xfrom)
 if (isFloatingPoint!R && isFloatingPoint!X);
 pure nothrow @nogc @trusted Rcopysign(R, X)(Xto, Rfrom)
 if (isIntegral!X && isFloatingPoint!R);
- Parameters:R tothe numeric value to use X fromthe sign value to use Returns:a value composed of to with from's sign bit.Examples:writeln(copysign(1.0, 1.0)); // 1.0 writeln(copysign(1.0, -0.0)); // -1.0 writeln(copysign(1UL, -1.0)); // -1.0 writeln(copysign(-1.0, -1.0)); // -1.0 writeln(copysign(real.infinity, -1.0)); // -real.infinity assert(copysign(real.nan, 1.0) is real.nan); assert(copysign(-real.nan, 1.0) is real.nan); assert(copysign(real.nan, -1.0) is -real.nan); 
- pure nothrow @nogc @safe Fsgn(F)(Fx)
 if (isFloatingPoint!F || isIntegral!F);
- Returns -1 if x < 0,xif x == 0, 1 if x > 0, and NAN if x==NAN.Examples:writeln(sgn(168.1234)); // 1 writeln(sgn(-168.1234)); // -1 writeln(sgn(0.0)); // 0 writeln(sgn(-0.0)); // 0 
- pure nothrow @nogc @safe boolisPowerOf2(X)(const Xx)
 if (isNumeric!X);
- Check whether a number is an integer power of two.Note that only positive numbers can be integer powers of two. This function always return false ifxis negative or zero.Parameters:X xthe number to test Returns:true ifxis an integer power of two.Examples:import std.math.exponential : pow; assert( isPowerOf2(1.0L)); assert( isPowerOf2(2.0L)); assert( isPowerOf2(0.5L)); assert( isPowerOf2(pow(2.0L, 96))); assert( isPowerOf2(pow(2.0L, -77))); assert(!isPowerOf2(-2.0L)); assert(!isPowerOf2(-0.5L)); assert(!isPowerOf2(0.0L)); assert(!isPowerOf2(4.315)); assert(!isPowerOf2(1.0L / 3.0L)); assert(!isPowerOf2(real.nan)); assert(!isPowerOf2(real.infinity)); Examples:assert( isPowerOf2(1)); assert( isPowerOf2(2)); assert( isPowerOf2(1uL << 63)); assert(!isPowerOf2(-4)); assert(!isPowerOf2(0)); assert(!isPowerOf2(1337u)); 
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