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diff --git a/gcc-4.4.3/libstdc++-v3/doc/html/ext/pb_ds/priority_queue_text_modify_up_timing_test.html b/gcc-4.4.3/libstdc++-v3/doc/html/ext/pb_ds/priority_queue_text_modify_up_timing_test.html new file mode 100644 index 000000000..72a1e0a75 --- /dev/null +++ b/gcc-4.4.3/libstdc++-v3/doc/html/ext/pb_ds/priority_queue_text_modify_up_timing_test.html @@ -0,0 +1,222 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> + +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> +<head> +<meta name="generator" content="HTML Tidy for Linux/x86 (vers 12 April 2005), see www.w3.org" /> +<title>Priority Queue Text Modify (Up) Timing Test</title> +<meta http-equiv="Content-Type" content="text/html; charset=us-ascii" /> +</head> +<body> +<div id="page"> +<h1>Priority Queue Text <tt>modify</tt> Timing Test - I</h1> +<h2><a name="description" id="description">Description</a></h2> +<p>This test inserts a number of values with keys from an + arbitrary text ([ <a href="references.html#wickland96thirty">wickland96thirty</a> ]) into + into a container then modifies each one "up" (<i>i.e.,</i> it + makes it larger). It uses <tt>modify</tt> for <tt>pb_ds</tt>'s + priority queues; for the STL's priority queues, it pops values + from a container until it reaches the value that should be + modified, then pushes values back in. It measures the average + time for <tt>modify</tt> as a function of the number of + values.</p> +<p>(The test was executed with <a href="http://gcc.gnu.org/viewcvs/*checkout*/trunk/libstdc%2B%2B-v3/testsuite/performance/ext/pb_ds/priority_queue_text_modify_timing.cc"><tt>priority_queue_text_modify_up_timing_test</tt></a> + thirty_years_among_the_dead_preproc.txt 200 200 2100 t)</p> +<h2><a name="purpose" id="purpose">Purpose</a></h2> +<p>The test checks the effect of different underlying + data structures (see <a href="pq_design.html#pq_imp">Design::Priority + Queues::Implementations</a>) for graph algorithms settings. + Note that making an arbitrary value larger (in the sense of the + priority queue's comparison functor) corresponds to + decrease-key in standard graph algorithms [<a href="references.html#clrs2001">clrs2001</a>].</p> +<h2><a name="results" id="results">Results</a></h2> +<p>Figures <a href="#NPG">NPG</a>, <a href="#NPM">NPM</a>, and + <a href="#NPL">NPL</a> show the results for the native priority + queues and <tt>pb_ds</tt> 's priority queues in <a href="pq_performance_tests.html#gcc"><u>g++</u></a>, <a href="pq_performance_tests.html#msvc"><u>msvc++</u></a>, and + <a href="pq_performance_tests.html#local"><u>local</u></a>, + respectively; Figures <a href="#NRTG">NRTG</a>, <a href="#NRTM">NRTM</a>, and <a href="#NRTL">NRTL</a> show the results + for the pairing heap and thin heaps in <a href="pq_performance_tests.html#gcc"><u>g++</u></a>, <a href="pq_performance_tests.html#msvc"><u>msvc++</u></a>, and + <a href="pq_performance_tests.html#local"><u>local</u></a>, + respectively,</p> +<div id="NPG_res_div"> +<div id="NPG_gcc"> +<div id="NPG_priority_queue_text_modify_up_timing_test"> +<div id="NPG_pq"> +<div id="NPG_Native_and__tt_pb_ds_455tt__priority_queue__tt_modify_455tt__timing_test"><div style="border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NPG" id="NPG"><img src="priority_queue_text_modify_up_timing_test_gcc.png" alt="no image" /></a></h6>NPG: Native and <tt>pb ds</tt> priority queue <tt>modify</tt> timing test - <a href="pq_performance_tests.html#gcc">g++</a><p>In the above figure, the names in the legends have the following meaning:</p> +<ol> +<li> +n_pq_deque- +<tt>std::priority_queue</tt> adapting <tt>std::deque</tt></li> +<li> +n_pq_vector- +<tt>std::priority_queue</tt> adapting <tt>std::vector</tt></li> +<li> +binary_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="binary_heap_tag.html"><tt>binary_heap_tag</tt></a> +</li> +<li> +rc_binomial_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="rc_binomial_heap_tag.html"><tt>rc_binomial_heap_tag</tt></a> +</li> +<li> +pairing_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a> +</li> +<li> +binomial_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="binomial_heap_tag.html"><tt>binomial_heap_tag</tt></a> +</li> +<li> +thin_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="thin_heap_tag.html"><tt>thin_heap_tag</tt></a> +</li> +</ol> +</div><div style="width: 100%; height: 20px"></div></div> +</div> +</div> +</div> +</div> +<div id="NPM_res_div"> +<div id="NPM_msvc"> +<div id="NPM_priority_queue_text_modify_up_timing_test"> +<div id="NPM_pq"> +<div id="NPM_Native_and__tt_pb_ds_455tt__priority_queue__tt_modify_455tt__timing_test"><div style="border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NPM" id="NPM"><img src="priority_queue_text_modify_up_timing_test_msvc.png" alt="no image" /></a></h6>NPM: Native and <tt>pb ds</tt> priority queue <tt>modify</tt> timing test - <a href="pq_performance_tests.html#msvc">msvc++</a><p>In the above figure, the names in the legends have the following meaning:</p> +<ol> +<li> +n_pq_deque- +<tt>std::priority_queue</tt> adapting <tt>std::deque</tt></li> +<li> +n_pq_vector- +<tt>std::priority_queue</tt> adapting <tt>std::vector</tt></li> +<li> +binary_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="binary_heap_tag.html"><tt>binary_heap_tag</tt></a> +</li> +<li> +rc_binomial_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="rc_binomial_heap_tag.html"><tt>rc_binomial_heap_tag</tt></a> +</li> +<li> +pairing_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a> +</li> +<li> +binomial_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="binomial_heap_tag.html"><tt>binomial_heap_tag</tt></a> +</li> +<li> +thin_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="thin_heap_tag.html"><tt>thin_heap_tag</tt></a> +</li> +</ol> +</div><div style="width: 100%; height: 20px"></div></div> +</div> +</div> +</div> +</div> +<div id="NPL_res_div"> +<div id="NPL_local"> +<div id="NPL_priority_queue_text_modify_up_timing_test"> +<div id="NPL_pq"> +<div id="NPL_Native_and__tt_pb_ds_455tt__priority_queue__tt_modify_455tt__timing_test"><div style = "border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NPL" id= "NPL"><img src="priority_queue_text_modify_up_timing_test_local.png" alt="no image" /></a></h6>NPL: Native and <tt>pb ds</tt> priority queue <tt>modify</tt> timing test - <a href = "pq_performance_tests.html#local">local</a></div><div style = "width: 100%; height: 20px"></div></div> +</div> +</div> +</div> +</div> +<div id="NRTG_res_div"> +<div id="NRTG_gcc"> +<div id="NRTG_priority_queue_text_modify_up_timing_test_pairing_thin"> +<div id="NRTG_pq"> +<div id="NRTG_Pairing_and_thin__priority_queue__tt_modify_455tt__timing_test"><div style="border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NRTG" id="NRTG"><img src="priority_queue_text_modify_up_timing_test_pairing_thin_gcc.png" alt="no image" /></a></h6>NRTG: Pairing and thin priority queue <tt>modify</tt> timing test - <a href="pq_performance_tests.html#gcc">g++</a><p>In the above figure, the names in the legends have the following meaning:</p> +<ol> +<li> +pairing_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a> +</li> +<li> +thin_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="thin_heap_tag.html"><tt>thin_heap_tag</tt></a> +</li> +</ol> +</div><div style="width: 100%; height: 20px"></div></div> +</div> +</div> +</div> +</div> +<div id="NRTM_res_div"> +<div id="NRTM_msvc"> +<div id="NRTM_priority_queue_text_modify_up_timing_test_pairing_thin"> +<div id="NRTM_pq"> +<div id="NRTM_Pairing_and_thin__priority_queue__tt_modify_455tt__timing_test"><div style="border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NRTM" id="NRTM"><img src="priority_queue_text_modify_up_timing_test_pairing_thin_msvc.png" alt="no image" /></a></h6>NRTM: Pairing and thin priority queue <tt>modify</tt> timing test - <a href="pq_performance_tests.html#msvc">msvc++</a><p>In the above figure, the names in the legends have the following meaning:</p> +<ol> +<li> +pairing_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a> +</li> +<li> +thin_heap- +<a href="priority_queue.html"><tt>priority_queue</tt></a> + with <tt>Tag</tt> = <a href="thin_heap_tag.html"><tt>thin_heap_tag</tt></a> +</li> +</ol> +</div><div style="width: 100%; height: 20px"></div></div> +</div> +</div> +</div> +</div> +<div id="NRTL_res_div"> +<div id="NRTL_local"> +<div id="NRTL_priority_queue_text_modify_up_timing_test_pairing_thin"> +<div id="NRTL_pq"> +<div id="NRTL_Pairing_and_thin__priority_queue__tt_modify_455tt__timing_test"><div style = "border-style: dotted; border-width: 1px; border-color: lightgray"><h6 class="c1"><a name="NRTL" id= "NRTL"><img src="priority_queue_text_modify_up_timing_test_pairing_thin_local.png" alt="no image" /></a></h6>NRTL: Pairing and thin priority queue <tt>modify</tt> timing test - <a href = "pq_performance_tests.html#local">local</a></div><div style = "width: 100%; height: 20px"></div></div> +</div> +</div> +</div> +</div> +<h2><a name="observations" id="observations">Observations</a></h2> +<p>As noted above, increasing an arbitrary value (in the sense + of the priority queue's comparison functor) is very common in + graph-related algorithms. In this case, a thin heap (<a href="priority_queue.html"><tt>priority_queue</tt></a> with + <tt>Tag</tt> = <a href="thin_heap_tag.html"><tt>thin_heap_tag</tt></a>) + outperforms a pairing heap (<a href="priority_queue.html"><tt>priority_queue</tt></a> with + <tt>Tag</tt> = <a href="pairing_heap_tag.html"><tt>pairing_heap_tag</tt></a>). + Conversely, <a href="priority_queue_text_push_timing_test.html">Priority Queue Text + <tt>push</tt> Timing Test</a>, <a href="priority_queue_text_push_pop_timing_test.html">Priority Queue + Text <tt>push</tt> and <tt>pop</tt> Timing Test</a>, <a href="priority_queue_random_int_push_timing_test.html">Priority + Queue Random Integer <tt>push</tt> Timing Test</a>, and + <a href="priority_queue_random_int_push_pop_timing_test.html">Priority + Queue Random Integer <tt>push</tt> and <tt>pop</tt> Timing + Test</a> show that the situation is reversed for other + operations. It is not clear when to prefer one of these two + different types.</p> +<p>In this test <tt>pb_ds</tt>'s binary heaps effectively + perform modify in linear time. As explained in <a href="pq_design.html#pq_traits">Priority Queue Design::Traits</a>, + given a valid point-type iterator, a binary heap can perform + <tt>modify</tt> logarithmically. The problem is that binary + heaps invalidate their find iterators with each modifying + operation, and so the only way to obtain a valid point-type + iterator is to iterate using a range-type iterator until + finding the appropriate value, then use the range-type iterator + for the <tt>modify</tt> operation.</p> +<p>The explanation for the STL's priority queues' performance + is similar to that in <a href="priority_queue_text_join_timing_test.html">Priority Queue Text + <tt>join</tt> Timing Test</a>.</p> +<p><a href="pq_performance_tests.html#pq_observations">Priority-Queue + Performance Tests::Observations</a> discusses this further and + summarizes.</p> +</div> +</body> +</html> |