Brian Silverman | 32ed54e | 2018-08-04 23:37:28 -0700 | [diff] [blame^] | 1 | [def __effects [*Effects: ]] |
| 2 | [def __formula [*Formula: ]] |
| 3 | [def __exm1 '''<code>e<superscript>x</superscript> - 1</code>'''] |
| 4 | [def __ex '''<code>e<superscript>x</superscript></code>'''] |
| 5 | [def __te '''2ε'''] |
| 6 | |
| 7 | [mathpart inverse_complex..Complex Number Functions] |
| 8 | |
| 9 | The following complex number algorithms are the inverses of trigonometric functions currently |
| 10 | present in the C++ standard. Equivalents to these functions are part of the C99 standard, and |
| 11 | are part of the [tr1]. |
| 12 | |
| 13 | [section:complex_implementation Implementation and Accuracy] |
| 14 | |
| 15 | Although there are deceptively simple formulae available for all of these functions, a naive |
| 16 | implementation that used these formulae would fail catastrophically for some input |
| 17 | values. The Boost versions of these functions have been implemented using the methodology |
| 18 | described in "Implementing the Complex Arcsine and Arccosine Functions Using Exception Handling" |
| 19 | by T. E. Hull Thomas F. Fairgrieve and Ping Tak Peter Tang, ACM Transactions on Mathematical Software, |
| 20 | Vol. 23, No. 3, September 1997. This means that the functions are well defined over the entire |
| 21 | complex number range, and produce accurate values even at the extremes of that range, where as a naive |
| 22 | formula would cause overflow or underflow to occur during the calculation, even though the result is |
| 23 | actually a representable value. The maximum theoretical relative error for all of these functions |
| 24 | is less than 9.5[epsilon] for every machine-representable point in the complex plane. Please refer to |
| 25 | comments in the header files themselves and to the above mentioned paper for more information |
| 26 | on the implementation methodology. |
| 27 | |
| 28 | [endsect] |
| 29 | |
| 30 | [section:asin asin] |
| 31 | |
| 32 | [h4 Header:] |
| 33 | |
| 34 | #include <boost/math/complex/asin.hpp> |
| 35 | |
| 36 | [h4 Synopsis:] |
| 37 | |
| 38 | template<class T> |
| 39 | std::complex<T> asin(const std::complex<T>& z); |
| 40 | |
| 41 | __effects returns the inverse sine of the complex number z. |
| 42 | |
| 43 | __formula [$../images/asin.png] |
| 44 | |
| 45 | [endsect] |
| 46 | |
| 47 | [section:acos acos] |
| 48 | |
| 49 | [h4 Header:] |
| 50 | |
| 51 | #include <boost/math/complex/acos.hpp> |
| 52 | |
| 53 | [h4 Synopsis:] |
| 54 | |
| 55 | template<class T> |
| 56 | std::complex<T> acos(const std::complex<T>& z); |
| 57 | |
| 58 | __effects returns the inverse cosine of the complex number z. |
| 59 | |
| 60 | __formula [$../images/acos.png] |
| 61 | |
| 62 | [endsect] |
| 63 | |
| 64 | [section:atan atan] |
| 65 | |
| 66 | [h4 Header:] |
| 67 | |
| 68 | #include <boost/math/complex/atan.hpp> |
| 69 | |
| 70 | [h4 Synopsis:] |
| 71 | |
| 72 | template<class T> |
| 73 | std::complex<T> atan(const std::complex<T>& z); |
| 74 | |
| 75 | __effects returns the inverse tangent of the complex number z. |
| 76 | |
| 77 | __formula [$../images/atan.png] |
| 78 | |
| 79 | [endsect] |
| 80 | |
| 81 | [section:asinh asinh] |
| 82 | |
| 83 | [h4 Header:] |
| 84 | |
| 85 | #include <boost/math/complex/asinh.hpp> |
| 86 | |
| 87 | [h4 Synopsis:] |
| 88 | |
| 89 | template<class T> |
| 90 | std::complex<T> asinh(const std::complex<T>& z); |
| 91 | |
| 92 | __effects returns the inverse hyperbolic sine of the complex number z. |
| 93 | |
| 94 | __formula [$../images/asinh.png] |
| 95 | |
| 96 | [endsect] |
| 97 | |
| 98 | [section:acosh acosh] |
| 99 | |
| 100 | [h4 Header:] |
| 101 | |
| 102 | #include <boost/math/complex/acosh.hpp> |
| 103 | |
| 104 | [h4 Synopsis:] |
| 105 | |
| 106 | template<class T> |
| 107 | std::complex<T> acosh(const std::complex<T>& z); |
| 108 | |
| 109 | __effects returns the inverse hyperbolic cosine of the complex number z. |
| 110 | |
| 111 | __formula [$../images/acosh.png] |
| 112 | |
| 113 | [endsect] |
| 114 | |
| 115 | [section:atanh atanh] |
| 116 | |
| 117 | [h4 Header:] |
| 118 | |
| 119 | #include <boost/math/complex/atanh.hpp> |
| 120 | |
| 121 | [h4 Synopsis:] |
| 122 | |
| 123 | template<class T> |
| 124 | std::complex<T> atanh(const std::complex<T>& z); |
| 125 | |
| 126 | __effects returns the inverse hyperbolic tangent of the complex number z. |
| 127 | |
| 128 | __formula [$../images/atanh.png] |
| 129 | |
| 130 | [endsect] |
| 131 | |
| 132 | [section:complex_history History] |
| 133 | |
| 134 | * 2005/12/17: Added support for platforms with no meaningful numeric_limits<>::infinity(). |
| 135 | * 2005/12/01: Initial version, added as part of the TR1 library. |
| 136 | |
| 137 | |
| 138 | [endsect] |
| 139 | |
| 140 | [endmathpart] |
| 141 | |
| 142 | [/ |
| 143 | Copyright 2008, 2009 John Maddock and Paul A. Bristow. |
| 144 | Distributed under the Boost Software License, Version 1.0. |
| 145 | (See accompanying file LICENSE_1_0.txt or copy at |
| 146 | http://www.boost.org/LICENSE_1_0.txt). |
| 147 | ] |
| 148 | |
| 149 | |