path: root/devdocs/go/math%2Findex.html

<h1> Package math  </h1>     <ul id="short-nav">
<li><code>import "math"</code></li>
<li><a href="#pkg-overview" class="overviewLink">Overview</a></li>
<li><a href="#pkg-index" class="indexLink">Index</a></li>
<li><a href="#pkg-examples" class="examplesLink">Examples</a></li>
<li><a href="#pkg-subdirectories">Subdirectories</a></li>
</ul>     <h2 id="pkg-overview">Overview </h2> <p>Package math provides basic constants and mathematical functions. </p>
<p>This package does not guarantee bit-identical results across architectures. </p>     <h2 id="pkg-index">Index </h2>  <ul id="manual-nav">
<li><a href="#pkg-constants">Constants</a></li>
<li><a href="#Abs">func Abs(x float64) float64</a></li>
<li><a href="#Acos">func Acos(x float64) float64</a></li>
<li><a href="#Acosh">func Acosh(x float64) float64</a></li>
<li><a href="#Asin">func Asin(x float64) float64</a></li>
<li><a href="#Asinh">func Asinh(x float64) float64</a></li>
<li><a href="#Atan">func Atan(x float64) float64</a></li>
<li><a href="#Atan2">func Atan2(y, x float64) float64</a></li>
<li><a href="#Atanh">func Atanh(x float64) float64</a></li>
<li><a href="#Cbrt">func Cbrt(x float64) float64</a></li>
<li><a href="#Ceil">func Ceil(x float64) float64</a></li>
<li><a href="#Copysign">func Copysign(f, sign float64) float64</a></li>
<li><a href="#Cos">func Cos(x float64) float64</a></li>
<li><a href="#Cosh">func Cosh(x float64) float64</a></li>
<li><a href="#Dim">func Dim(x, y float64) float64</a></li>
<li><a href="#Erf">func Erf(x float64) float64</a></li>
<li><a href="#Erfc">func Erfc(x float64) float64</a></li>
<li><a href="#Erfcinv">func Erfcinv(x float64) float64</a></li>
<li><a href="#Erfinv">func Erfinv(x float64) float64</a></li>
<li><a href="#Exp">func Exp(x float64) float64</a></li>
<li><a href="#Exp2">func Exp2(x float64) float64</a></li>
<li><a href="#Expm1">func Expm1(x float64) float64</a></li>
<li><a href="#FMA">func FMA(x, y, z float64) float64</a></li>
<li><a href="#Float32bits">func Float32bits(f float32) uint32</a></li>
<li><a href="#Float32frombits">func Float32frombits(b uint32) float32</a></li>
<li><a href="#Float64bits">func Float64bits(f float64) uint64</a></li>
<li><a href="#Float64frombits">func Float64frombits(b uint64) float64</a></li>
<li><a href="#Floor">func Floor(x float64) float64</a></li>
<li><a href="#Frexp">func Frexp(f float64) (frac float64, exp int)</a></li>
<li><a href="#Gamma">func Gamma(x float64) float64</a></li>
<li><a href="#Hypot">func Hypot(p, q float64) float64</a></li>
<li><a href="#Ilogb">func Ilogb(x float64) int</a></li>
<li><a href="#Inf">func Inf(sign int) float64</a></li>
<li><a href="#IsInf">func IsInf(f float64, sign int) bool</a></li>
<li><a href="#IsNaN">func IsNaN(f float64) (is bool)</a></li>
<li><a href="#J0">func J0(x float64) float64</a></li>
<li><a href="#J1">func J1(x float64) float64</a></li>
<li><a href="#Jn">func Jn(n int, x float64) float64</a></li>
<li><a href="#Ldexp">func Ldexp(frac float64, exp int) float64</a></li>
<li><a href="#Lgamma">func Lgamma(x float64) (lgamma float64, sign int)</a></li>
<li><a href="#Log">func Log(x float64) float64</a></li>
<li><a href="#Log10">func Log10(x float64) float64</a></li>
<li><a href="#Log1p">func Log1p(x float64) float64</a></li>
<li><a href="#Log2">func Log2(x float64) float64</a></li>
<li><a href="#Logb">func Logb(x float64) float64</a></li>
<li><a href="#Max">func Max(x, y float64) float64</a></li>
<li><a href="#Min">func Min(x, y float64) float64</a></li>
<li><a href="#Mod">func Mod(x, y float64) float64</a></li>
<li><a href="#Modf">func Modf(f float64) (int float64, frac float64)</a></li>
<li><a href="#NaN">func NaN() float64</a></li>
<li><a href="#Nextafter">func Nextafter(x, y float64) (r float64)</a></li>
<li><a href="#Nextafter32">func Nextafter32(x, y float32) (r float32)</a></li>
<li><a href="#Pow">func Pow(x, y float64) float64</a></li>
<li><a href="#Pow10">func Pow10(n int) float64</a></li>
<li><a href="#Remainder">func Remainder(x, y float64) float64</a></li>
<li><a href="#Round">func Round(x float64) float64</a></li>
<li><a href="#RoundToEven">func RoundToEven(x float64) float64</a></li>
<li><a href="#Signbit">func Signbit(x float64) bool</a></li>
<li><a href="#Sin">func Sin(x float64) float64</a></li>
<li><a href="#Sincos">func Sincos(x float64) (sin, cos float64)</a></li>
<li><a href="#Sinh">func Sinh(x float64) float64</a></li>
<li><a href="#Sqrt">func Sqrt(x float64) float64</a></li>
<li><a href="#Tan">func Tan(x float64) float64</a></li>
<li><a href="#Tanh">func Tanh(x float64) float64</a></li>
<li><a href="#Trunc">func Trunc(x float64) float64</a></li>
<li><a href="#Y0">func Y0(x float64) float64</a></li>
<li><a href="#Y1">func Y1(x float64) float64</a></li>
<li><a href="#Yn">func Yn(n int, x float64) float64</a></li>
</ul> <div id="pkg-examples"> <h3>Examples</h3>  <dl> <dd><a class="exampleLink" href="#example_Abs">Abs</a></dd> <dd><a class="exampleLink" href="#example_Acos">Acos</a></dd> <dd><a class="exampleLink" href="#example_Acosh">Acosh</a></dd> <dd><a class="exampleLink" href="#example_Asin">Asin</a></dd> <dd><a class="exampleLink" href="#example_Asinh">Asinh</a></dd> <dd><a class="exampleLink" href="#example_Atan">Atan</a></dd> <dd><a class="exampleLink" href="#example_Atan2">Atan2</a></dd> <dd><a class="exampleLink" href="#example_Atanh">Atanh</a></dd> <dd><a class="exampleLink" href="#example_Cbrt">Cbrt</a></dd> <dd><a class="exampleLink" href="#example_Ceil">Ceil</a></dd> <dd><a class="exampleLink" href="#example_Copysign">Copysign</a></dd> <dd><a class="exampleLink" href="#example_Cos">Cos</a></dd> <dd><a class="exampleLink" href="#example_Cosh">Cosh</a></dd> <dd><a class="exampleLink" href="#example_Dim">Dim</a></dd> <dd><a class="exampleLink" href="#example_Exp">Exp</a></dd> <dd><a class="exampleLink" href="#example_Exp2">Exp2</a></dd> <dd><a class="exampleLink" href="#example_Expm1">Expm1</a></dd> <dd><a class="exampleLink" href="#example_Floor">Floor</a></dd> <dd><a class="exampleLink" href="#example_Log">Log</a></dd> <dd><a class="exampleLink" href="#example_Log10">Log10</a></dd> <dd><a class="exampleLink" href="#example_Log2">Log2</a></dd> <dd><a class="exampleLink" href="#example_Mod">Mod</a></dd> <dd><a class="exampleLink" href="#example_Modf">Modf</a></dd> <dd><a class="exampleLink" href="#example_Pow">Pow</a></dd> <dd><a class="exampleLink" href="#example_Pow10">Pow10</a></dd> <dd><a class="exampleLink" href="#example_Remainder">Remainder</a></dd> <dd><a class="exampleLink" href="#example_Round">Round</a></dd> <dd><a class="exampleLink" href="#example_RoundToEven">RoundToEven</a></dd> <dd><a class="exampleLink" href="#example_Sin">Sin</a></dd> <dd><a class="exampleLink" href="#example_Sincos">Sincos</a></dd> <dd><a class="exampleLink" href="#example_Sinh">Sinh</a></dd> <dd><a class="exampleLink" href="#example_Sqrt">Sqrt</a></dd> <dd><a class="exampleLink" href="#example_Tan">Tan</a></dd> <dd><a class="exampleLink" href="#example_Tanh">Tanh</a></dd> <dd><a class="exampleLink" href="#example_Trunc">Trunc</a></dd> </dl> </div> <h3>Package files</h3> <p>  <span>abs.go</span> <span>acosh.go</span> <span>asin.go</span> <span>asinh.go</span> <span>atan.go</span> <span>atan2.go</span> <span>atanh.go</span> <span>bits.go</span> <span>cbrt.go</span> <span>const.go</span> <span>copysign.go</span> <span>dim.go</span> <span>dim_asm.go</span> <span>erf.go</span> <span>erfinv.go</span> <span>exp.go</span> <span>exp2_noasm.go</span> <span>exp_amd64.go</span> <span>exp_asm.go</span> <span>expm1.go</span> <span>floor.go</span> <span>floor_asm.go</span> <span>fma.go</span> <span>frexp.go</span> <span>gamma.go</span> <span>hypot.go</span> <span>hypot_asm.go</span> <span>j0.go</span> <span>j1.go</span> <span>jn.go</span> <span>ldexp.go</span> <span>lgamma.go</span> <span>log.go</span> <span>log10.go</span> <span>log1p.go</span> <span>log_asm.go</span> <span>logb.go</span> <span>mod.go</span> <span>modf.go</span> <span>modf_noasm.go</span> <span>nextafter.go</span> <span>pow.go</span> <span>pow10.go</span> <span>remainder.go</span> <span>signbit.go</span> <span>sin.go</span> <span>sincos.go</span> <span>sinh.go</span> <span>sqrt.go</span> <span>stubs.go</span> <span>tan.go</span> <span>tanh.go</span> <span>trig_reduce.go</span> <span>unsafe.go</span>  </p>   <h2 id="pkg-constants">Constants</h2> <p>Mathematical constants. </p>
<pre data-language="go">const (
    E   = 2.71828182845904523536028747135266249775724709369995957496696763 // https://oeis.org/A001113
    Pi  = 3.14159265358979323846264338327950288419716939937510582097494459 // https://oeis.org/A000796
    Phi = 1.61803398874989484820458683436563811772030917980576286213544862 // https://oeis.org/A001622

    Sqrt2   = 1.41421356237309504880168872420969807856967187537694807317667974 // https://oeis.org/A002193
    SqrtE   = 1.64872127070012814684865078781416357165377610071014801157507931 // https://oeis.org/A019774
    SqrtPi  = 1.77245385090551602729816748334114518279754945612238712821380779 // https://oeis.org/A002161
    SqrtPhi = 1.27201964951406896425242246173749149171560804184009624861664038 // https://oeis.org/A139339

    Ln2    = 0.693147180559945309417232121458176568075500134360255254120680009 // https://oeis.org/A002162
    Log2E  = 1 / Ln2
    Ln10   = 2.30258509299404568401799145468436420760110148862877297603332790 // https://oeis.org/A002392
    Log10E = 1 / Ln10
)</pre> <p>Floating-point limit values. Max is the largest finite value representable by the type. SmallestNonzero is the smallest positive, non-zero value representable by the type. </p>
<pre data-language="go">const (
    MaxFloat32             = 0x1p127 * (1 + (1 - 0x1p-23)) // 3.40282346638528859811704183484516925440e+38
    SmallestNonzeroFloat32 = 0x1p-126 * 0x1p-23            // 1.401298464324817070923729583289916131280e-45

    MaxFloat64             = 0x1p1023 * (1 + (1 - 0x1p-52)) // 1.79769313486231570814527423731704356798070e+308
    SmallestNonzeroFloat64 = 0x1p-1022 * 0x1p-52            // 4.9406564584124654417656879286822137236505980e-324
)</pre> <p>Integer limit values. </p>
<pre data-language="go">const (
    MaxInt    = 1&lt;&lt;(intSize-1) - 1  // MaxInt32 or MaxInt64 depending on intSize.
    MinInt    = -1 &lt;&lt; (intSize - 1) // MinInt32 or MinInt64 depending on intSize.
    MaxInt8   = 1&lt;&lt;7 - 1            // 127
    MinInt8   = -1 &lt;&lt; 7             // -128
    MaxInt16  = 1&lt;&lt;15 - 1           // 32767
    MinInt16  = -1 &lt;&lt; 15            // -32768
    MaxInt32  = 1&lt;&lt;31 - 1           // 2147483647
    MinInt32  = -1 &lt;&lt; 31            // -2147483648
    MaxInt64  = 1&lt;&lt;63 - 1           // 9223372036854775807
    MinInt64  = -1 &lt;&lt; 63            // -9223372036854775808
    MaxUint   = 1&lt;&lt;intSize - 1      // MaxUint32 or MaxUint64 depending on intSize.
    MaxUint8  = 1&lt;&lt;8 - 1            // 255
    MaxUint16 = 1&lt;&lt;16 - 1           // 65535
    MaxUint32 = 1&lt;&lt;32 - 1           // 4294967295
    MaxUint64 = 1&lt;&lt;64 - 1           // 18446744073709551615
)</pre> <h2 id="Abs">func <span>Abs</span>  </h2> <pre data-language="go">func Abs(x float64) float64</pre> <p>Abs returns the absolute value of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Abs(±Inf) = +Inf
Abs(NaN) = NaN
</pre>    <h4 id="example_Abs"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">x := math.Abs(-2)
fmt.Printf("%.1f\n", x)

y := math.Abs(2)
fmt.Printf("%.1f\n", y)
</pre> <p>Output:</p> <pre class="output" data-language="go">2.0
2.0
</pre>   <h2 id="Acos">func <span>Acos</span>  </h2> <pre data-language="go">func Acos(x float64) float64</pre> <p>Acos returns the arccosine, in radians, of x. </p>
<p>Special case is: </p>
<pre data-language="go">Acos(x) = NaN if x &lt; -1 or x &gt; 1
</pre>    <h4 id="example_Acos"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Acos(1))
</pre> <p>Output:</p> <pre class="output" data-language="go">0.00
</pre>   <h2 id="Acosh">func <span>Acosh</span>  </h2> <pre data-language="go">func Acosh(x float64) float64</pre> <p>Acosh returns the inverse hyperbolic cosine of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Acosh(+Inf) = +Inf
Acosh(x) = NaN if x &lt; 1
Acosh(NaN) = NaN
</pre>    <h4 id="example_Acosh"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Acosh(1))
</pre> <p>Output:</p> <pre class="output" data-language="go">0.00
</pre>   <h2 id="Asin">func <span>Asin</span>  </h2> <pre data-language="go">func Asin(x float64) float64</pre> <p>Asin returns the arcsine, in radians, of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Asin(±0) = ±0
Asin(x) = NaN if x &lt; -1 or x &gt; 1
</pre>    <h4 id="example_Asin"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Asin(0))
</pre> <p>Output:</p> <pre class="output" data-language="go">0.00
</pre>   <h2 id="Asinh">func <span>Asinh</span>  </h2> <pre data-language="go">func Asinh(x float64) float64</pre> <p>Asinh returns the inverse hyperbolic sine of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Asinh(±0) = ±0
Asinh(±Inf) = ±Inf
Asinh(NaN) = NaN
</pre>    <h4 id="example_Asinh"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Asinh(0))
</pre> <p>Output:</p> <pre class="output" data-language="go">0.00
</pre>   <h2 id="Atan">func <span>Atan</span>  </h2> <pre data-language="go">func Atan(x float64) float64</pre> <p>Atan returns the arctangent, in radians, of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Atan(±0) = ±0
Atan(±Inf) = ±Pi/2
</pre>    <h4 id="example_Atan"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Atan(0))
</pre> <p>Output:</p> <pre class="output" data-language="go">0.00
</pre>   <h2 id="Atan2">func <span>Atan2</span>  </h2> <pre data-language="go">func Atan2(y, x float64) float64</pre> <p>Atan2 returns the arc tangent of y/x, using the signs of the two to determine the quadrant of the return value. </p>
<p>Special cases are (in order): </p>
<pre data-language="go">Atan2(y, NaN) = NaN
Atan2(NaN, x) = NaN
Atan2(+0, x&gt;=0) = +0
Atan2(-0, x&gt;=0) = -0
Atan2(+0, x&lt;=-0) = +Pi
Atan2(-0, x&lt;=-0) = -Pi
Atan2(y&gt;0, 0) = +Pi/2
Atan2(y&lt;0, 0) = -Pi/2
Atan2(+Inf, +Inf) = +Pi/4
Atan2(-Inf, +Inf) = -Pi/4
Atan2(+Inf, -Inf) = 3Pi/4
Atan2(-Inf, -Inf) = -3Pi/4
Atan2(y, +Inf) = 0
Atan2(y&gt;0, -Inf) = +Pi
Atan2(y&lt;0, -Inf) = -Pi
Atan2(+Inf, x) = +Pi/2
Atan2(-Inf, x) = -Pi/2
</pre>    <h4 id="example_Atan2"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Atan2(0, 0))
</pre> <p>Output:</p> <pre class="output" data-language="go">0.00
</pre>   <h2 id="Atanh">func <span>Atanh</span>  </h2> <pre data-language="go">func Atanh(x float64) float64</pre> <p>Atanh returns the inverse hyperbolic tangent of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Atanh(1) = +Inf
Atanh(±0) = ±0
Atanh(-1) = -Inf
Atanh(x) = NaN if x &lt; -1 or x &gt; 1
Atanh(NaN) = NaN
</pre>    <h4 id="example_Atanh"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Atanh(0))
</pre> <p>Output:</p> <pre class="output" data-language="go">0.00
</pre>   <h2 id="Cbrt">func <span>Cbrt</span>  </h2> <pre data-language="go">func Cbrt(x float64) float64</pre> <p>Cbrt returns the cube root of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Cbrt(±0) = ±0
Cbrt(±Inf) = ±Inf
Cbrt(NaN) = NaN
</pre>    <h4 id="example_Cbrt"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f\n", math.Cbrt(8))
fmt.Printf("%.2f\n", math.Cbrt(27))
</pre> <p>Output:</p> <pre class="output" data-language="go">2.00
3.00
</pre>   <h2 id="Ceil">func <span>Ceil</span>  </h2> <pre data-language="go">func Ceil(x float64) float64</pre> <p>Ceil returns the least integer value greater than or equal to x. </p>
<p>Special cases are: </p>
<pre data-language="go">Ceil(±0) = ±0
Ceil(±Inf) = ±Inf
Ceil(NaN) = NaN
</pre>    <h4 id="example_Ceil"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">c := math.Ceil(1.49)
fmt.Printf("%.1f", c)
</pre> <p>Output:</p> <pre class="output" data-language="go">2.0
</pre>   <h2 id="Copysign">func <span>Copysign</span>  </h2> <pre data-language="go">func Copysign(f, sign float64) float64</pre> <p>Copysign returns a value with the magnitude of f and the sign of sign. </p>   <h4 id="example_Copysign"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Copysign(3.2, -1))
</pre> <p>Output:</p> <pre class="output" data-language="go">-3.20
</pre>   <h2 id="Cos">func <span>Cos</span>  </h2> <pre data-language="go">func Cos(x float64) float64</pre> <p>Cos returns the cosine of the radian argument x. </p>
<p>Special cases are: </p>
<pre data-language="go">Cos(±Inf) = NaN
Cos(NaN) = NaN
</pre>    <h4 id="example_Cos"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Cos(math.Pi/2))
</pre> <p>Output:</p> <pre class="output" data-language="go">0.00
</pre>   <h2 id="Cosh">func <span>Cosh</span>  </h2> <pre data-language="go">func Cosh(x float64) float64</pre> <p>Cosh returns the hyperbolic cosine of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Cosh(±0) = 1
Cosh(±Inf) = +Inf
Cosh(NaN) = NaN
</pre>    <h4 id="example_Cosh"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Cosh(0))
</pre> <p>Output:</p> <pre class="output" data-language="go">1.00
</pre>   <h2 id="Dim">func <span>Dim</span>  </h2> <pre data-language="go">func Dim(x, y float64) float64</pre> <p>Dim returns the maximum of x-y or 0. </p>
<p>Special cases are: </p>
<pre data-language="go">Dim(+Inf, +Inf) = NaN
Dim(-Inf, -Inf) = NaN
Dim(x, NaN) = Dim(NaN, x) = NaN
</pre>    <h4 id="example_Dim"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f\n", math.Dim(4, -2))
fmt.Printf("%.2f\n", math.Dim(-4, 2))
</pre> <p>Output:</p> <pre class="output" data-language="go">6.00
0.00
</pre>   <h2 id="Erf">func <span>Erf</span>  </h2> <pre data-language="go">func Erf(x float64) float64</pre> <p>Erf returns the error function of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Erf(+Inf) = 1
Erf(-Inf) = -1
Erf(NaN) = NaN
</pre> <h2 id="Erfc">func <span>Erfc</span>  </h2> <pre data-language="go">func Erfc(x float64) float64</pre> <p>Erfc returns the complementary error function of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Erfc(+Inf) = 0
Erfc(-Inf) = 2
Erfc(NaN) = NaN
</pre> <h2 id="Erfcinv">func <span>Erfcinv</span>  <span title="Added in Go 1.10">1.10</span> </h2> <pre data-language="go">func Erfcinv(x float64) float64</pre> <p>Erfcinv returns the inverse of <a href="#Erfc">Erfc</a>(x). </p>
<p>Special cases are: </p>
<pre data-language="go">Erfcinv(0) = +Inf
Erfcinv(2) = -Inf
Erfcinv(x) = NaN if x &lt; 0 or x &gt; 2
Erfcinv(NaN) = NaN
</pre> <h2 id="Erfinv">func <span>Erfinv</span>  <span title="Added in Go 1.10">1.10</span> </h2> <pre data-language="go">func Erfinv(x float64) float64</pre> <p>Erfinv returns the inverse error function of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Erfinv(1) = +Inf
Erfinv(-1) = -Inf
Erfinv(x) = NaN if x &lt; -1 or x &gt; 1
Erfinv(NaN) = NaN
</pre> <h2 id="Exp">func <span>Exp</span>  </h2> <pre data-language="go">func Exp(x float64) float64</pre> <p>Exp returns e**x, the base-e exponential of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Exp(+Inf) = +Inf
Exp(NaN) = NaN
</pre> <p>Very large values overflow to 0 or +Inf. Very small values underflow to 1. </p>   <h4 id="example_Exp"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f\n", math.Exp(1))
fmt.Printf("%.2f\n", math.Exp(2))
fmt.Printf("%.2f\n", math.Exp(-1))
</pre> <p>Output:</p> <pre class="output" data-language="go">2.72
7.39
0.37
</pre>   <h2 id="Exp2">func <span>Exp2</span>  </h2> <pre data-language="go">func Exp2(x float64) float64</pre> <p>Exp2 returns 2**x, the base-2 exponential of x. </p>
<p>Special cases are the same as <a href="#Exp">Exp</a>. </p>   <h4 id="example_Exp2"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f\n", math.Exp2(1))
fmt.Printf("%.2f\n", math.Exp2(-3))
</pre> <p>Output:</p> <pre class="output" data-language="go">2.00
0.12
</pre>   <h2 id="Expm1">func <span>Expm1</span>  </h2> <pre data-language="go">func Expm1(x float64) float64</pre> <p>Expm1 returns e**x - 1, the base-e exponential of x minus 1. It is more accurate than <a href="#Exp">Exp</a>(x) - 1 when x is near zero. </p>
<p>Special cases are: </p>
<pre data-language="go">Expm1(+Inf) = +Inf
Expm1(-Inf) = -1
Expm1(NaN) = NaN
</pre> <p>Very large values overflow to -1 or +Inf. </p>   <h4 id="example_Expm1"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.6f\n", math.Expm1(0.01))
fmt.Printf("%.6f\n", math.Expm1(-1))
</pre> <p>Output:</p> <pre class="output" data-language="go">0.010050
-0.632121
</pre>   <h2 id="FMA">func <span>FMA</span>  <span title="Added in Go 1.14">1.14</span> </h2> <pre data-language="go">func FMA(x, y, z float64) float64</pre> <p>FMA returns x * y + z, computed with only one rounding. (That is, FMA returns the fused multiply-add of x, y, and z.) </p>
<h2 id="Float32bits">func <span>Float32bits</span>  </h2> <pre data-language="go">func Float32bits(f float32) uint32</pre> <p>Float32bits returns the IEEE 754 binary representation of f, with the sign bit of f and the result in the same bit position. Float32bits(Float32frombits(x)) == x. </p>
<h2 id="Float32frombits">func <span>Float32frombits</span>  </h2> <pre data-language="go">func Float32frombits(b uint32) float32</pre> <p>Float32frombits returns the floating-point number corresponding to the IEEE 754 binary representation b, with the sign bit of b and the result in the same bit position. Float32frombits(Float32bits(x)) == x. </p>
<h2 id="Float64bits">func <span>Float64bits</span>  </h2> <pre data-language="go">func Float64bits(f float64) uint64</pre> <p>Float64bits returns the IEEE 754 binary representation of f, with the sign bit of f and the result in the same bit position, and Float64bits(Float64frombits(x)) == x. </p>
<h2 id="Float64frombits">func <span>Float64frombits</span>  </h2> <pre data-language="go">func Float64frombits(b uint64) float64</pre> <p>Float64frombits returns the floating-point number corresponding to the IEEE 754 binary representation b, with the sign bit of b and the result in the same bit position. Float64frombits(Float64bits(x)) == x. </p>
<h2 id="Floor">func <span>Floor</span>  </h2> <pre data-language="go">func Floor(x float64) float64</pre> <p>Floor returns the greatest integer value less than or equal to x. </p>
<p>Special cases are: </p>
<pre data-language="go">Floor(±0) = ±0
Floor(±Inf) = ±Inf
Floor(NaN) = NaN
</pre>    <h4 id="example_Floor"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">c := math.Floor(1.51)
fmt.Printf("%.1f", c)
</pre> <p>Output:</p> <pre class="output" data-language="go">1.0
</pre>   <h2 id="Frexp">func <span>Frexp</span>  </h2> <pre data-language="go">func Frexp(f float64) (frac float64, exp int)</pre> <p>Frexp breaks f into a normalized fraction and an integral power of two. It returns frac and exp satisfying f == frac × 2**exp, with the absolute value of frac in the interval [½, 1). </p>
<p>Special cases are: </p>
<pre data-language="go">Frexp(±0) = ±0, 0
Frexp(±Inf) = ±Inf, 0
Frexp(NaN) = NaN, 0
</pre> <h2 id="Gamma">func <span>Gamma</span>  </h2> <pre data-language="go">func Gamma(x float64) float64</pre> <p>Gamma returns the Gamma function of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Gamma(+Inf) = +Inf
Gamma(+0) = +Inf
Gamma(-0) = -Inf
Gamma(x) = NaN for integer x &lt; 0
Gamma(-Inf) = NaN
Gamma(NaN) = NaN
</pre> <h2 id="Hypot">func <span>Hypot</span>  </h2> <pre data-language="go">func Hypot(p, q float64) float64</pre> <p>Hypot returns <a href="#Sqrt">Sqrt</a>(p*p + q*q), taking care to avoid unnecessary overflow and underflow. </p>
<p>Special cases are: </p>
<pre data-language="go">Hypot(±Inf, q) = +Inf
Hypot(p, ±Inf) = +Inf
Hypot(NaN, q) = NaN
Hypot(p, NaN) = NaN
</pre> <h2 id="Ilogb">func <span>Ilogb</span>  </h2> <pre data-language="go">func Ilogb(x float64) int</pre> <p>Ilogb returns the binary exponent of x as an integer. </p>
<p>Special cases are: </p>
<pre data-language="go">Ilogb(±Inf) = MaxInt32
Ilogb(0) = MinInt32
Ilogb(NaN) = MaxInt32
</pre> <h2 id="Inf">func <span>Inf</span>  </h2> <pre data-language="go">func Inf(sign int) float64</pre> <p>Inf returns positive infinity if sign &gt;= 0, negative infinity if sign &lt; 0. </p>
<h2 id="IsInf">func <span>IsInf</span>  </h2> <pre data-language="go">func IsInf(f float64, sign int) bool</pre> <p>IsInf reports whether f is an infinity, according to sign. If sign &gt; 0, IsInf reports whether f is positive infinity. If sign &lt; 0, IsInf reports whether f is negative infinity. If sign == 0, IsInf reports whether f is either infinity. </p>
<h2 id="IsNaN">func <span>IsNaN</span>  </h2> <pre data-language="go">func IsNaN(f float64) (is bool)</pre> <p>IsNaN reports whether f is an IEEE 754 “not-a-number” value. </p>
<h2 id="J0">func <span>J0</span>  </h2> <pre data-language="go">func J0(x float64) float64</pre> <p>J0 returns the order-zero Bessel function of the first kind. </p>
<p>Special cases are: </p>
<pre data-language="go">J0(±Inf) = 0
J0(0) = 1
J0(NaN) = NaN
</pre> <h2 id="J1">func <span>J1</span>  </h2> <pre data-language="go">func J1(x float64) float64</pre> <p>J1 returns the order-one Bessel function of the first kind. </p>
<p>Special cases are: </p>
<pre data-language="go">J1(±Inf) = 0
J1(NaN) = NaN
</pre> <h2 id="Jn">func <span>Jn</span>  </h2> <pre data-language="go">func Jn(n int, x float64) float64</pre> <p>Jn returns the order-n Bessel function of the first kind. </p>
<p>Special cases are: </p>
<pre data-language="go">Jn(n, ±Inf) = 0
Jn(n, NaN) = NaN
</pre> <h2 id="Ldexp">func <span>Ldexp</span>  </h2> <pre data-language="go">func Ldexp(frac float64, exp int) float64</pre> <p>Ldexp is the inverse of <a href="#Frexp">Frexp</a>. It returns frac × 2**exp. </p>
<p>Special cases are: </p>
<pre data-language="go">Ldexp(±0, exp) = ±0
Ldexp(±Inf, exp) = ±Inf
Ldexp(NaN, exp) = NaN
</pre> <h2 id="Lgamma">func <span>Lgamma</span>  </h2> <pre data-language="go">func Lgamma(x float64) (lgamma float64, sign int)</pre> <p>Lgamma returns the natural logarithm and sign (-1 or +1) of <a href="#Gamma">Gamma</a>(x). </p>
<p>Special cases are: </p>
<pre data-language="go">Lgamma(+Inf) = +Inf
Lgamma(0) = +Inf
Lgamma(-integer) = +Inf
Lgamma(-Inf) = -Inf
Lgamma(NaN) = NaN
</pre> <h2 id="Log">func <span>Log</span>  </h2> <pre data-language="go">func Log(x float64) float64</pre> <p>Log returns the natural logarithm of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Log(+Inf) = +Inf
Log(0) = -Inf
Log(x &lt; 0) = NaN
Log(NaN) = NaN
</pre>    <h4 id="example_Log"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">x := math.Log(1)
fmt.Printf("%.1f\n", x)

y := math.Log(2.7183)
fmt.Printf("%.1f\n", y)
</pre> <p>Output:</p> <pre class="output" data-language="go">0.0
1.0
</pre>   <h2 id="Log10">func <span>Log10</span>  </h2> <pre data-language="go">func Log10(x float64) float64</pre> <p>Log10 returns the decimal logarithm of x. The special cases are the same as for <a href="#Log">Log</a>. </p>   <h4 id="example_Log10"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.1f", math.Log10(100))
</pre> <p>Output:</p> <pre class="output" data-language="go">2.0
</pre>   <h2 id="Log1p">func <span>Log1p</span>  </h2> <pre data-language="go">func Log1p(x float64) float64</pre> <p>Log1p returns the natural logarithm of 1 plus its argument x. It is more accurate than <a href="#Log">Log</a>(1 + x) when x is near zero. </p>
<p>Special cases are: </p>
<pre data-language="go">Log1p(+Inf) = +Inf
Log1p(±0) = ±0
Log1p(-1) = -Inf
Log1p(x &lt; -1) = NaN
Log1p(NaN) = NaN
</pre> <h2 id="Log2">func <span>Log2</span>  </h2> <pre data-language="go">func Log2(x float64) float64</pre> <p>Log2 returns the binary logarithm of x. The special cases are the same as for <a href="#Log">Log</a>. </p>   <h4 id="example_Log2"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.1f", math.Log2(256))
</pre> <p>Output:</p> <pre class="output" data-language="go">8.0
</pre>   <h2 id="Logb">func <span>Logb</span>  </h2> <pre data-language="go">func Logb(x float64) float64</pre> <p>Logb returns the binary exponent of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Logb(±Inf) = +Inf
Logb(0) = -Inf
Logb(NaN) = NaN
</pre> <h2 id="Max">func <span>Max</span>  </h2> <pre data-language="go">func Max(x, y float64) float64</pre> <p>Max returns the larger of x or y. </p>
<p>Special cases are: </p>
<pre data-language="go">Max(x, +Inf) = Max(+Inf, x) = +Inf
Max(x, NaN) = Max(NaN, x) = NaN
Max(+0, ±0) = Max(±0, +0) = +0
Max(-0, -0) = -0
</pre> <p>Note that this differs from the built-in function max when called with NaN and +Inf. </p>
<h2 id="Min">func <span>Min</span>  </h2> <pre data-language="go">func Min(x, y float64) float64</pre> <p>Min returns the smaller of x or y. </p>
<p>Special cases are: </p>
<pre data-language="go">Min(x, -Inf) = Min(-Inf, x) = -Inf
Min(x, NaN) = Min(NaN, x) = NaN
Min(-0, ±0) = Min(±0, -0) = -0
</pre> <p>Note that this differs from the built-in function min when called with NaN and -Inf. </p>
<h2 id="Mod">func <span>Mod</span>  </h2> <pre data-language="go">func Mod(x, y float64) float64</pre> <p>Mod returns the floating-point remainder of x/y. The magnitude of the result is less than y and its sign agrees with that of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Mod(±Inf, y) = NaN
Mod(NaN, y) = NaN
Mod(x, 0) = NaN
Mod(x, ±Inf) = x
Mod(x, NaN) = NaN
</pre>    <h4 id="example_Mod"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">c := math.Mod(7, 4)
fmt.Printf("%.1f", c)
</pre> <p>Output:</p> <pre class="output" data-language="go">3.0
</pre>   <h2 id="Modf">func <span>Modf</span>  </h2> <pre data-language="go">func Modf(f float64) (int float64, frac float64)</pre> <p>Modf returns integer and fractional floating-point numbers that sum to f. Both values have the same sign as f. </p>
<p>Special cases are: </p>
<pre data-language="go">Modf(±Inf) = ±Inf, NaN
Modf(NaN) = NaN, NaN
</pre>    <h4 id="example_Modf"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">int, frac := math.Modf(3.14)
fmt.Printf("%.2f, %.2f\n", int, frac)

int, frac = math.Modf(-2.71)
fmt.Printf("%.2f, %.2f\n", int, frac)
</pre> <p>Output:</p> <pre class="output" data-language="go">3.00, 0.14
-2.00, -0.71
</pre>   <h2 id="NaN">func <span>NaN</span>  </h2> <pre data-language="go">func NaN() float64</pre> <p>NaN returns an IEEE 754 “not-a-number” value. </p>
<h2 id="Nextafter">func <span>Nextafter</span>  </h2> <pre data-language="go">func Nextafter(x, y float64) (r float64)</pre> <p>Nextafter returns the next representable float64 value after x towards y. </p>
<p>Special cases are: </p>
<pre data-language="go">Nextafter(x, x)   = x
Nextafter(NaN, y) = NaN
Nextafter(x, NaN) = NaN
</pre> <h2 id="Nextafter32">func <span>Nextafter32</span>  <span title="Added in Go 1.4">1.4</span> </h2> <pre data-language="go">func Nextafter32(x, y float32) (r float32)</pre> <p>Nextafter32 returns the next representable float32 value after x towards y. </p>
<p>Special cases are: </p>
<pre data-language="go">Nextafter32(x, x)   = x
Nextafter32(NaN, y) = NaN
Nextafter32(x, NaN) = NaN
</pre> <h2 id="Pow">func <span>Pow</span>  </h2> <pre data-language="go">func Pow(x, y float64) float64</pre> <p>Pow returns x**y, the base-x exponential of y. </p>
<p>Special cases are (in order): </p>
<pre data-language="go">Pow(x, ±0) = 1 for any x
Pow(1, y) = 1 for any y
Pow(x, 1) = x for any x
Pow(NaN, y) = NaN
Pow(x, NaN) = NaN
Pow(±0, y) = ±Inf for y an odd integer &lt; 0
Pow(±0, -Inf) = +Inf
Pow(±0, +Inf) = +0
Pow(±0, y) = +Inf for finite y &lt; 0 and not an odd integer
Pow(±0, y) = ±0 for y an odd integer &gt; 0
Pow(±0, y) = +0 for finite y &gt; 0 and not an odd integer
Pow(-1, ±Inf) = 1
Pow(x, +Inf) = +Inf for |x| &gt; 1
Pow(x, -Inf) = +0 for |x| &gt; 1
Pow(x, +Inf) = +0 for |x| &lt; 1
Pow(x, -Inf) = +Inf for |x| &lt; 1
Pow(+Inf, y) = +Inf for y &gt; 0
Pow(+Inf, y) = +0 for y &lt; 0
Pow(-Inf, y) = Pow(-0, -y)
Pow(x, y) = NaN for finite x &lt; 0 and finite non-integer y
</pre>    <h4 id="example_Pow"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">c := math.Pow(2, 3)
fmt.Printf("%.1f", c)
</pre> <p>Output:</p> <pre class="output" data-language="go">8.0
</pre>   <h2 id="Pow10">func <span>Pow10</span>  </h2> <pre data-language="go">func Pow10(n int) float64</pre> <p>Pow10 returns 10**n, the base-10 exponential of n. </p>
<p>Special cases are: </p>
<pre data-language="go">Pow10(n) =    0 for n &lt; -323
Pow10(n) = +Inf for n &gt; 308
</pre>    <h4 id="example_Pow10"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">c := math.Pow10(2)
fmt.Printf("%.1f", c)
</pre> <p>Output:</p> <pre class="output" data-language="go">100.0
</pre>   <h2 id="Remainder">func <span>Remainder</span>  </h2> <pre data-language="go">func Remainder(x, y float64) float64</pre> <p>Remainder returns the IEEE 754 floating-point remainder of x/y. </p>
<p>Special cases are: </p>
<pre data-language="go">Remainder(±Inf, y) = NaN
Remainder(NaN, y) = NaN
Remainder(x, 0) = NaN
Remainder(x, ±Inf) = x
Remainder(x, NaN) = NaN
</pre>    <h4 id="example_Remainder"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.1f", math.Remainder(100, 30))
</pre> <p>Output:</p> <pre class="output" data-language="go">10.0
</pre>   <h2 id="Round">func <span>Round</span>  <span title="Added in Go 1.10">1.10</span> </h2> <pre data-language="go">func Round(x float64) float64</pre> <p>Round returns the nearest integer, rounding half away from zero. </p>
<p>Special cases are: </p>
<pre data-language="go">Round(±0) = ±0
Round(±Inf) = ±Inf
Round(NaN) = NaN
</pre>    <h4 id="example_Round"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">p := math.Round(10.5)
fmt.Printf("%.1f\n", p)

n := math.Round(-10.5)
fmt.Printf("%.1f\n", n)
</pre> <p>Output:</p> <pre class="output" data-language="go">11.0
-11.0
</pre>   <h2 id="RoundToEven">func <span>RoundToEven</span>  <span title="Added in Go 1.10">1.10</span> </h2> <pre data-language="go">func RoundToEven(x float64) float64</pre> <p>RoundToEven returns the nearest integer, rounding ties to even. </p>
<p>Special cases are: </p>
<pre data-language="go">RoundToEven(±0) = ±0
RoundToEven(±Inf) = ±Inf
RoundToEven(NaN) = NaN
</pre>    <h4 id="example_RoundToEven"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">u := math.RoundToEven(11.5)
fmt.Printf("%.1f\n", u)

d := math.RoundToEven(12.5)
fmt.Printf("%.1f\n", d)
</pre> <p>Output:</p> <pre class="output" data-language="go">12.0
12.0
</pre>   <h2 id="Signbit">func <span>Signbit</span>  </h2> <pre data-language="go">func Signbit(x float64) bool</pre> <p>Signbit reports whether x is negative or negative zero. </p>
<h2 id="Sin">func <span>Sin</span>  </h2> <pre data-language="go">func Sin(x float64) float64</pre> <p>Sin returns the sine of the radian argument x. </p>
<p>Special cases are: </p>
<pre data-language="go">Sin(±0) = ±0
Sin(±Inf) = NaN
Sin(NaN) = NaN
</pre>    <h4 id="example_Sin"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Sin(math.Pi))
</pre> <p>Output:</p> <pre class="output" data-language="go">0.00
</pre>   <h2 id="Sincos">func <span>Sincos</span>  </h2> <pre data-language="go">func Sincos(x float64) (sin, cos float64)</pre> <p>Sincos returns Sin(x), Cos(x). </p>
<p>Special cases are: </p>
<pre data-language="go">Sincos(±0) = ±0, 1
Sincos(±Inf) = NaN, NaN
Sincos(NaN) = NaN, NaN
</pre>    <h4 id="example_Sincos"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">sin, cos := math.Sincos(0)
fmt.Printf("%.2f, %.2f", sin, cos)
</pre> <p>Output:</p> <pre class="output" data-language="go">0.00, 1.00
</pre>   <h2 id="Sinh">func <span>Sinh</span>  </h2> <pre data-language="go">func Sinh(x float64) float64</pre> <p>Sinh returns the hyperbolic sine of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Sinh(±0) = ±0
Sinh(±Inf) = ±Inf
Sinh(NaN) = NaN
</pre>    <h4 id="example_Sinh"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Sinh(0))
</pre> <p>Output:</p> <pre class="output" data-language="go">0.00
</pre>   <h2 id="Sqrt">func <span>Sqrt</span>  </h2> <pre data-language="go">func Sqrt(x float64) float64</pre> <p>Sqrt returns the square root of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Sqrt(+Inf) = +Inf
Sqrt(±0) = ±0
Sqrt(x &lt; 0) = NaN
Sqrt(NaN) = NaN
</pre>    <h4 id="example_Sqrt"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">const (
    a = 3
    b = 4
)
c := math.Sqrt(a*a + b*b)
fmt.Printf("%.1f", c)
</pre> <p>Output:</p> <pre class="output" data-language="go">5.0
</pre>   <h2 id="Tan">func <span>Tan</span>  </h2> <pre data-language="go">func Tan(x float64) float64</pre> <p>Tan returns the tangent of the radian argument x. </p>
<p>Special cases are: </p>
<pre data-language="go">Tan(±0) = ±0
Tan(±Inf) = NaN
Tan(NaN) = NaN
</pre>    <h4 id="example_Tan"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Tan(0))
</pre> <p>Output:</p> <pre class="output" data-language="go">0.00
</pre>   <h2 id="Tanh">func <span>Tanh</span>  </h2> <pre data-language="go">func Tanh(x float64) float64</pre> <p>Tanh returns the hyperbolic tangent of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Tanh(±0) = ±0
Tanh(±Inf) = ±1
Tanh(NaN) = NaN
</pre>    <h4 id="example_Tanh"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f", math.Tanh(0))
</pre> <p>Output:</p> <pre class="output" data-language="go">0.00
</pre>   <h2 id="Trunc">func <span>Trunc</span>  </h2> <pre data-language="go">func Trunc(x float64) float64</pre> <p>Trunc returns the integer value of x. </p>
<p>Special cases are: </p>
<pre data-language="go">Trunc(±0) = ±0
Trunc(±Inf) = ±Inf
Trunc(NaN) = NaN
</pre>    <h4 id="example_Trunc"> <span class="text">Example</span>
</h4> <p>Code:</p> <pre class="code" data-language="go">fmt.Printf("%.2f\n", math.Trunc(math.Pi))
fmt.Printf("%.2f\n", math.Trunc(-1.2345))
</pre> <p>Output:</p> <pre class="output" data-language="go">3.00
-1.00
</pre>   <h2 id="Y0">func <span>Y0</span>  </h2> <pre data-language="go">func Y0(x float64) float64</pre> <p>Y0 returns the order-zero Bessel function of the second kind. </p>
<p>Special cases are: </p>
<pre data-language="go">Y0(+Inf) = 0
Y0(0) = -Inf
Y0(x &lt; 0) = NaN
Y0(NaN) = NaN
</pre> <h2 id="Y1">func <span>Y1</span>  </h2> <pre data-language="go">func Y1(x float64) float64</pre> <p>Y1 returns the order-one Bessel function of the second kind. </p>
<p>Special cases are: </p>
<pre data-language="go">Y1(+Inf) = 0
Y1(0) = -Inf
Y1(x &lt; 0) = NaN
Y1(NaN) = NaN
</pre> <h2 id="Yn">func <span>Yn</span>  </h2> <pre data-language="go">func Yn(n int, x float64) float64</pre> <p>Yn returns the order-n Bessel function of the second kind. </p>
<p>Special cases are: </p>
<pre data-language="go">Yn(n, +Inf) = 0
Yn(n ≥ 0, 0) = -Inf
Yn(n &lt; 0, 0) = +Inf if n is odd, -Inf if n is even
Yn(n, x &lt; 0) = NaN
Yn(n, NaN) = NaN
</pre> <h2 id="pkg-subdirectories">Subdirectories</h2> <div class="pkg-dir"> <table> <tr> <th class="pkg-name">Name</th> <th class="pkg-synopsis">Synopsis</th> </tr> <tr> <td colspan="2"><a href="../index">..</a></td> </tr> <tr> <td class="pkg-name"> <a href="big/index">big</a> </td> <td class="pkg-synopsis"> Package big implements arbitrary-precision arithmetic (big numbers). </td> </tr> <tr> <td class="pkg-name"> <a href="bits/index">bits</a> </td> <td class="pkg-synopsis"> Package bits implements bit counting and manipulation functions for the predeclared unsigned integer types. </td> </tr> <tr> <td class="pkg-name"> <a href="cmplx/index">cmplx</a> </td> <td class="pkg-synopsis"> Package cmplx provides basic constants and mathematical functions for complex numbers. </td> </tr> <tr> <td class="pkg-name"> <a href="rand/index">rand</a> </td> <td class="pkg-synopsis"> Package rand implements pseudo-random number generators suitable for tasks such as simulation, but it should not be used for security-sensitive work. </td> </tr> <tr> <td class="pkg-name"> <a href="rand/v2/index">v2</a> </td> <td class="pkg-synopsis"> Package rand implements pseudo-random number generators suitable for tasks such as simulation, but it should not be used for security-sensitive work. </td> </tr> </table> </div><div class="_attribution">
  <p class="_attribution-p">
    &copy; Google, Inc.<br>Licensed under the Creative Commons Attribution License 3.0.<br>
    <a href="http://golang.org/pkg/math/" class="_attribution-link">http://golang.org/pkg/math/</a>
  </p>
</div>