{"id":17,"date":"2016-11-18T20:03:26","date_gmt":"2016-11-18T20:03:26","guid":{"rendered":"http:\/\/python.wp.w3.pt\/?p=17"},"modified":"2016-11-18T23:25:46","modified_gmt":"2016-11-18T23:25:46","slug":"objetos","status":"publish","type":"post","link":"http:\/\/python.w3.pt\/?p=17","title":{"rendered":"Objetos"},"content":{"rendered":"<p>Exemplo de uma sess\u00e3o em Python que mostra algumas fun\u00e7\u00f5es de manipula\u00e7\u00e3o de objetos<\/p>\n<pre>Python 2.7.12 (default, Sep\u00a0 6 2016, 18:21:48)\r\n[GCC 5.4.0] on linux2\r\nType \"help\", \"copyright\", \"credits\" or \"license\" for more information.\r\n&gt;&gt;&gt; type(4)\r\n&lt;type 'int'&gt;\r\n&gt;&gt;&gt; type(\"\"\"a\"\"\")\r\n&lt;type 'str'&gt;\r\n&gt;&gt;&gt; type(type(\"\"\"a\"\"\"))\r\n&lt;type 'type'&gt;\r\n&gt;&gt;&gt; id(45)\r\n15021312\r\n&gt;&gt;&gt; id(34)\r\n15019584\r\n&gt;&gt;&gt; exit()\r\n<\/pre>\n<p>De notar que o tipo de um objeto tamb\u00e9m \u00e9 um objeto, de tipo <em>type<\/em>.<br \/>\nA fun\u00e7\u00e3o <em>id()<\/em> devolve o <em>id<\/em> do objeto, que pode ser pensado como o seu endere\u00e7o em mem\u00f3ria.<\/p>\n<p>Os inteiros com mais de 32 bits &#8211; para al\u00e9m de do intervalo [-2147483648, 2147483647] &#8211; s\u00e3o ineiros longos e n\u00e3o t\u00eam limite de tamanho, n\u00e3o est\u00e3o limitados a 64 bits como no Java ou no C.<\/p>\n<p>Segue-se um exemplo de utiliza\u00e7\u00e3o de n\u00fameros complexos em Python, em modo interativo<\/p>\n<pre>&gt;&gt;&gt; x=3\r\n&gt;&gt;&gt; type(x)\r\n&lt;type 'int'&gt;\r\n&gt;&gt;&gt; print(x)\r\n3\r\n&gt;&gt;&gt; x+=2j\r\n&gt;&gt;&gt; type(x)\r\n&lt;type 'complex'&gt;\r\n&gt;&gt;&gt; print(x.real)\r\n3.0\r\n&gt;&gt;&gt; type(x.real)\r\n&lt;type 'float'&gt;\r\n&gt;&gt;&gt; print(x.imag)\r\n2.0\r\n&gt;&gt;&gt; print(x)\r\n(3+2j)\r\n<\/pre>\n<p>De notar que as componentes de um complexo s\u00e3o sempre <em>float<\/em>, que \u00e9 um real de 64 bits.<\/p>\n<p>O Python permite cortar sequ\u00eancias (tuplos, strings, listas, etc.) dinamicamente. Por exemplo, <code class=\"docutils literal\"><span class=\"pre\">a[i:j]<\/span><\/code> seleciona todos os \u00edndices <em>k<\/em> tais que <em>i<\/em> <code class=\"docutils literal\"><span class=\"pre\">&lt;=<\/span><\/code> <em>k<\/em> <code class=\"docutils literal\"><span class=\"pre\">&lt;<\/span><\/code> <em>j<\/em>.<\/p>\n<p>Nalguns casos, \u00e9 poss\u00edvel um corte estendido, com um terceiro par\u00e2metro <code class=\"docutils literal\"><span class=\"pre\">k<\/span><\/code> tal que <code class=\"docutils literal\"><span class=\"pre\">a[i:j:k]<\/span><\/code> seleciona todos os elementos de <em>a<\/em> com \u00edndice <em>x<\/em> onde <code class=\"docutils literal\"><span class=\"pre\">x<\/span> <span class=\"pre\">=<\/span> <span class=\"pre\">i<\/span> <span class=\"pre\">+<\/span> <span class=\"pre\">n*k<\/span><\/code>, <em>n<\/em> <code class=\"docutils literal\"><span class=\"pre\">&gt;=<\/span><\/code> <code class=\"docutils literal\"><span class=\"pre\">0<\/span><\/code> e <em>i<\/em> <code class=\"docutils literal\"><span class=\"pre\">&lt;=<\/span><\/code> <em>x<\/em> <code class=\"docutils literal\"><span class=\"pre\">&lt;<\/span><\/code> <em>j<\/em>.<\/p>\n<p>A sequ\u00eancia resultado \u00e9 reindexada a partir do 0.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Exemplo de uma sess\u00e3o em Python que mostra algumas fun\u00e7\u00f5es de manipula\u00e7\u00e3o de objetos Python 2.7.12 (default, Sep\u00a0 6 2016, 18:21:48) [GCC 5.4.0] on linux2 Type &#8220;help&#8221;, &#8220;copyright&#8221;, &#8220;credits&#8221; or &#8220;license&#8221; for more information. &gt;&gt;&gt; type(4) &lt;type &#8216;int&#8217;&gt; &gt;&gt;&gt; type(&#8220;&#8221;&#8221;a&#8221;&#8221;&#8221;) &lt;type &#8216;str&#8217;&gt; &gt;&gt;&gt; type(type(&#8220;&#8221;&#8221;a&#8221;&#8221;&#8221;)) &lt;type &#8216;type&#8217;&gt; &gt;&gt;&gt; id(45) 15021312 &gt;&gt;&gt; id(34) 15019584 &gt;&gt;&gt; exit() De &hellip; <\/p>\n<p class=\"link-more\"><a href=\"http:\/\/python.w3.pt\/?p=17\" class=\"more-link\">Continuar a ler <span class=\"screen-reader-text\">&#8220;Objetos&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"_links":{"self":[{"href":"http:\/\/python.w3.pt\/index.php?rest_route=\/wp\/v2\/posts\/17"}],"collection":[{"href":"http:\/\/python.w3.pt\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/python.w3.pt\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/python.w3.pt\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/python.w3.pt\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=17"}],"version-history":[{"count":12,"href":"http:\/\/python.w3.pt\/index.php?rest_route=\/wp\/v2\/posts\/17\/revisions"}],"predecessor-version":[{"id":31,"href":"http:\/\/python.w3.pt\/index.php?rest_route=\/wp\/v2\/posts\/17\/revisions\/31"}],"wp:attachment":[{"href":"http:\/\/python.w3.pt\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=17"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/python.w3.pt\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=17"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/python.w3.pt\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=17"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}