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10 <title>Range and slice</title>
13 <h1><img src="../../../../boost.png" align="middle" />Range and Slice Storage</h1>
14 <div class="toc" id="toc"></div>
15 <h2><a name="range"></a>Range<SizeType,DistanceType></h2>
17 <p>The class <code>range</code> specifies a range of indicies. The range is a sequence of indices
18 from a start value to stop value. The indices increase by one and exlude the stop value.
19 <code>range</code> can therefore be used to specify ranges of elements from vectors and matrices.</p>
22 #include <boost/numeric/ublas/storage.hpp>
25 using namespace boost::numeric::ublas;
27 for (unsigned i = 0; i < r.size (); ++ i) {
28 std::cout << r (i) << std::endl;
33 <p>Defined in the header storage.hpp.</p>
35 <p>Reversible Container.</p>
36 <h4>Type requirements</h4>
37 <p>None, except for those imposed by the requirements of Reversible
39 <h4>Public base classes</h4>
42 <table border="1" summary="members">
49 <td><code>range (size_type start, size_type stop)</code></td>
50 <td>Constructs a range of indicies from <code>start</code> to <code>stop (excluded)</code>
54 <td><code>size_type start () const</code></td>
55 <td>Returns the beginning of the <code>range</code>.</td>
58 <td><code>size_type size () const</code></td>
59 <td>Returns the size of the <code>range</code>.</td>
62 <td><code>const_reference operator [] (size_type i)
64 <td>Returns the value <code>start + i</code> of the <code>i</code>
68 <td><code>range compose (const range &r) const</code></td>
69 <td>Returns the composite range from <code>start + r.start
70 ()</code> to <code>start + r.start () + r.size ()</code>.</td>
73 <td><code>bool operator == (const range &r) const</code></td>
74 <td>Tests two ranges for equality.</td>
77 <td><code>bool operator != (const range &r) const</code></td>
78 <td>Tests two ranges for inequality.</td>
81 <td><code>const_iterator begin () const</code></td>
82 <td>Returns a <code>const_iterator</code> pointing to the beginning
83 of the <code>range</code>.</td>
86 <td><code>const_iterator end () const</code></td>
87 <td>Returns a <code>const_iterator</code> pointing to the end of
88 the <code>range</code>.</td>
91 <td><code>const_reverse_iterator rbegin () const</code></td>
92 <td>Returns a <code>const_reverse_iterator</code> pointing to the
93 beginning of the reversed <code>range</code>.</td>
96 <td><code>const_reverse_iterator rend () const</code></td>
97 <td>Returns a <code>const_reverse_iterator</code> pointing to the
98 end of the reversed <code>range</code>.</td>
102 <h4>Preconditions</h4>
104 <li><code>start () <= stop ()</code></li>
107 <h2><a name="slice"></a>Slice<SizeType,DistanceType></h2>
109 <p>The class <code>slice</code> specifies a 'slice' of indicies. Slices are more general
110 then ranges, the stride allows the sequence of indicies to increase and decrease by the specified amount between element.
111 <code>slice</code> can therefore be used to specify slices of element from vectors and matrices.</p>
114 #include <boost/numeric/ublas/storage.hpp>
117 using namespace boost::numeric::ublas;
119 for (unsigned i = 0; i < s.size (); ++ i) {
120 std::cout << s (i) << std::endl;
125 <p>Defined in the header storage.hpp.</p>
127 <p>Reversible Container.</p>
128 <h4>Type requirements</h4>
129 <p>None, except for those imposed by the requirements of Reversible
131 <h4>Public base classes</h4>
134 <table border="1" summary="members">
141 <td><code>slice (size_type start, size_type stride, size_type
143 <td>Constructs a slice <code>start,start+stride,start+2*stride...</code> with
144 <code>size</code> elements.</td>
147 <td><code>size_type start () const</code></td>
148 <td>Returns the beginning of the <code>slice</code>.</td>
151 <td><code>size_type stride () const</code></td>
152 <td>Returns the stride of the <code>slice</code>.</td>
155 <td><code>size_type size () const</code></td>
156 <td>Returns the size of the <code>slice</code>.</td>
159 <td><code>const_reference operator [] (size_type i)
161 <td>Returns the value <code>start + i * stride</code> of the
162 <code>i</code>-th element.</td>
165 <td><code>slice compose (const range &r) const</code></td>
166 <td>Returns the composite slice from <code>start + stride * r.start
167 ()</code> to <code>start + stride * (r.start () + r.size ())</code>
168 with stride <code>stride</code>.</td>
171 <td><code>slice compose (const slice &s) const</code></td>
172 <td>Returns the composite slice from <code>start + stride * s.start
173 ()</code> to <code>start + stride * s.stride () * (s.start () +
174 s.size ())</code> with stride <code>stride * s.stride ()</code>
178 <td><code>bool operator == (const slice &s) const</code></td>
179 <td>Tests two slices for equality.</td>
182 <td><code>bool operator != (const slice &s) const</code></td>
183 <td>Tests two slices for inequality.</td>
186 <td><code>const_iterator begin () const</code></td>
187 <td>Returns a <code>const_iterator</code> pointing to the beginning
188 of the <code>slice</code>.</td>
191 <td><code>const_iterator end () const</code></td>
192 <td>Returns a <code>const_iterator</code> pointing to the end of
193 the <code>slice</code>.</td>
196 <td><code>const_reverse_iterator rbegin () const</code></td>
197 <td>Returns a <code>const_reverse_iterator</code> pointing to the
198 beginning of the reversed <code>slice</code>.</td>
201 <td><code>const_reverse_iterator rend () const</code></td>
202 <td>Returns a <code>const_reverse_iterator</code> pointing to the
203 end of the reversed <code>slice</code>.</td>
207 <h4>Preconditions</h4>
209 <li>None all strides are vaild. However when an index is returned or an iterator is dereferenced its
210 value must be representable as the size_type.</li>
214 Copyright (©) 2000-2004 Michael Stevens, Mathias Koch,
215 Joerg Walter, Gunter Winkler<br />
216 Use, modification and distribution are subject to the
217 Boost Software License, Version 1.0.
218 (See accompanying file LICENSE_1_0.txt
219 or copy at <a href="http://www.boost.org/LICENSE_1_0.txt">
220 http://www.boost.org/LICENSE_1_0.txt
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