CINXE.COM

<!DOCTYPE html><html lang='ja'><head><meta name='viewport' content='width=1024' /><meta http-equiv='Content-Type' content='text/html; charset=utf-8' /><meta http-equiv='content-style-type' content='text/css' /><meta http-equiv='content-script-type' content='text/javascript' /><meta name='keywords' content='計算,関数,公式,数学'/><meta name='description' content='円周率π をatanの四項級数からなる各種のATAN公式で計算します。'/><meta name='fragment' content='!' /><meta property="og:title" content="円周率計算（ATAN 4項級数）" /><meta property='og:type' content='website' /><meta property='og:url' content='https://keisan.casio.jp/exec/system/1258598283' /><meta property='og:image' content='https://keisan.casio.jp/keisan/pc/common/img/social.gif' /><meta property='og:description' content='円周率π をatanの四項級数からなる各種のATAN公式で計算します。' /><meta property='og:site_name' content='高精度計算サイト' /><title>円周率計算（ATAN 4項級数） - 高精度計算サイト</title><style>body {font-family: 'Arial', 'Helvetica', 'sans-serif';margin:0px;}td, th{font-family: 'Arial', 'Helvetica', 'sans-serif';}#mapalert{margin-left:5px; padding:3px; }</style><link rel='apple-touch-icon' href='/apple-touch-icon.png' /><link rel='stylesheet' type='text/css' href='/keisan/pc/css/Keisan.css?20200305' /><link rel='stylesheet' type='text/css' href='/keisan/pc/common/css/reset.css' media='all' /><link rel='stylesheet' type='text/css' href='/keisan/pc/common/css/common.css?20190822' media='all' /><script src='//ajax.googleapis.com/ajax/libs/jquery/3.6.4/jquery.min.js'></script><script>window.jQuery || document.write("<script src='/keisan/common/jquery/jquery.js'></scr" + "ipt>")</script><link rel='stylesheet' media='screen' href='//cdn.jsdelivr.net/npm/handsontable@6.2.2/dist/handsontable.min.css'><script src='//cdn.jsdelivr.net/npm/handsontable@6.2.2/dist/handsontable.min.js'></script><script>typeof Handsontable !== 'undefined' || document.write("<link rel='stylesheet' media='screen' href='/keisan/common/jquery/handsontable/jquery.handsontable.min.css?20180327'>")</script><script>typeof Handsontable !== 'undefined' || document.write("<script src='/keisan/common/jquery/handsontable/jquery.handsontable.min.js?20180327'></scr" + "ipt>")</script><link rel='stylesheet' href='//ajax.googleapis.com/ajax/libs/jqueryui/1.13.2/themes/smoothness/jquery-ui.min.css'><script type='text/x-mathjax-config'>MathJax.Hub.Config({ tex2jax: { processEscapes: true, }, displayAlign: 'left',}); </script><script src='//cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/MathJax.js?config=TeX-AMS_CHTML&locale=ja'></script><script>typeof MathJax !== 'undefined' || document.write("<script src='/keisan/common/js/MathJax-2.7.5/MathJax.js?config=TeX-AMS_CHTML&locale=ja'></scr" + "ipt>")</script><script src='/keisan/pc/common/js/tab_questionnaire.js'></script><script src='/keisan/pc/common/js/common.js?dummy=20190214'></script><script src='/keisan/libparam/js/libParam.js?20230906'></script></head><div id='wrap'> <div id="header"> <div class="inr"> <p id="header-logo"><a href="/"><img src="/keisan/pc/common/img/logo_keisan.gif" alt="keisan" /></a> <img src="/keisan/pc/common/img/img_txt_logo_keisan.gif" alt="生活や実務に役立つ高精度計算サイト" /></p> <div id="header-menu"> <div id="menu1"> <div id="menu1-inr"> <ul> <li><img src="/keisan/pc/common/img/ico_usr.gif" alt="" />ゲストさん</li> <li><img src="/keisan/pc/common/img/ico_usr_info.gif" alt="" /><a href="https://secure.casio.jp/keisan/jp/register/">新規会員登録</a></li> <li><img src="/keisan/pc/common/img/ico_login.gif" alt="" /><a href="https://secure.casio.jp/keisan/jp/members/login.php?">ログイン</a></li> </div> </div> <ul id="menu2" class="link-arw1"> <li><a href="/keisan/service.php">はじめに</a></li> <li><a href="/keisan/usage_exe.php">使い方</a></li> <li><a href="/keisan/calcsample.php">計算例</a></li> <li><a href='/' onclick="return dispselect(0)" id='switch_ps_sm'> スマートフォン </a></li>  </ul> </div> <div id="header-global"> <ul id="nav-global"> <li id="nav-global00"><a href="#menu" onclick='setTopTab2(0)'><span></span></a> <ul> <li class="sub01"><a href="/menu/system/000000000020">お金の計算</a></li> <li class="sub02"><a href="/menu/system/000000000120">健康の計算</a></li> <li class="sub03"><a href="/menu/system/000000000180">こよみの計算</a></li> <li class="sub04"><a href="/menu/system/000000000260">環境の計算</a></li> <li class="sub05"><a href="/menu/system/000000000360">単位の計算</a></li> <li class="sub06"><a href="/menu/system/000000000400">趣味・実用</a></li> </ul> </li> <li id="nav-global01"><a href="#menu" onclick='setTopTab2(1)'><span></span></a> <ul> <li class="sub01"><a href="/menu/system/000000000510">数学公式集</a></li> <li class="sub02"><a href="/menu/system/000000000670">物理公式集</a></li> <li class="sub03"><a href="/menu/system/000000000780">計算応用集</a></li> </ul> </li> <li id="nav-global02"><a href="#menu" onclick='setTopTab2(2)'><span></span></a> <ul> <li class="sub01"><a href="/menu/system/000000000850">統計関数</a></li> <li class="sub02"><a href="/menu/system/000000001070">特殊関数</a></li> <li class="sub04"><a href="/menu/system/000000001360">数値積分</a></li> <li class="sub05"><a href="/menu/system/000000001370">線形代数</a></li> <li class="sub03"><a href="/menu/system/000000001290">数値解析</a></li> </ul> </li> <li id="nav-global03"><a href="#menu" onclick='setTopTab2(3)'><span></span></a> <ul> <li class="sub01"><a href="/menu/user/000000002020">私の自作式</a></li> <li class="sub02"><a href="/menu/user/000000002050">みんな(生活)</a></li> <li class="sub03"><a href="/menu/user/000000002100">みんな(数学)</a></li> <li class="sub04"><a href="/menu/user/000000002140">みんな(科学)</a></li> <li class="sub05"><a href="/menu/user/000000002180">みんな(実学)</a></li> <li class="sub06"><a href="/menu/user/000000002220">みんな(その他)</a></li> </ul> </li>  <li id="nav-global04"><a href="/calculator"><span> </span></a> </li>  </ul> <div id="search"> <div id="search-inr"> <form action="/search" method="post" Accept-charset="utf-8"> <input type="hidden" name="lang" value="" /> <input type="hidden" name="pc" value="1" /> <div class="text"><input type="text" size="19" name="key" id="key" autocomplete="on" /></div> <div class="image"><input type="image" src="/keisan/pc/common/img/btn_search.gif" class="hov" / alt=""></div> </form> </div> </div> </div> </div> <noscript> <div id='noscript'> ご使用のブラウザは、JAVASCRIPTの設定がOFFになっているため一部の機能が制限されてます。 </div> </noscript> <script>var lang='';var is_pc=1; var loginflag=0; var nownicname='';</script> <script src='/keisan/common/js/KeisanHeader.js?20230516' charset='utf-8'></script> </div>  <body onpageshow="if(event.persisted){onLoadfunc();}" onLoad="onLoadfunc(); "><div id='contents'><div id='main-contents'><div class='col-tit'> <h1 class='title'><span class='ico0103' id='iconbar'>円周率計算（ATAN 4項級数） </span></h1></div><div class='bread-navi'><ol class='bread-crumbs'><li><a href='/'>ホーム</a></li><span id='allimage'></span><li> / <a href='/menu/system/000000000780'>計算応用集</a></li><li> / <a href='/menu/system/000000000820'>円周率計算</a></li></ol></div><div class='section'><div id='tb-col'><script> setHistoryList("円周率計算（ATAN 4項級数）",'', ''); sysUserCode='system/1258598283';</script><div class='scroolpnt'><table width='100%' border='0' cellspacing='0' cellpadding='0' id='toptable'><tr><td colspan=3 id='summary' class='top_left'><h2 class='title'>円周率π をatanの四項級数からなる各種のATAN公式で計算します。</h2></td></tr><tr><td colspan=3 align='center'></td></tr><tr><td colspan=2 align='center'><form name='calc'><input type='hidden' name='lang' value=''><input type='hidden' name='charset' value='utf-8'><table id='inparea'><tr><td colspan='3' class='center'><span id='myGraphA'></span></td></tr><tr><td colspan='2'><ul class='inner-table'><ol><li><span id='var_rm_disp'>rm</span></li><li><span id='var_rm_inp'><input size='0' autocomplete=off type='hidden' name='var_rm' id='var_rm' value='' class='text'></span></li><li><span id='var_rm_unit'></span></li><li><span id='var_rm_explain' class='execspoff'></span></li></ol></ul></td><td rowspan=3 class='center'><span id='myGraphB'></span></td></tr><tr><td class='right'><span id='var_f_disp'>計算公式</span></td><td><ul class='inner-table'><ol><li><select name='var_f' id='var_f' onchange="getOutTable2_1only( 'ATANformula4.csv', '公式,,,a1|a1,b1|b1,a2|a2,b2|b2,a3|a3,b3|b3,a4|a4,b4|b4,remark|rm', document.calc.var_f.selectedIndex, 0, '');"><option value='1' selected>ガウス 1863<option value='2' >ステルナー 1896<option value='3' >エスコット 1896<option value='4' >高野喜久雄 1982<option value='5' >村田健郎 1982<option value='6' >柴田昭彦 1983</select></li><li><span id='var_f_unit'></span></li><li><span id='var_f_explain' class='execspoff'></span></li><li><font color='blue' ><span id='var_n_disp'></span></font></li><li><span id='var_n_inp' disp_on_off='OFF'><input size='12' type='hidden' name='var_n' id='var_n' value='100'></span></li><li><font color='blue' ><span id='var_n_unit'></span></font></li><li><font color='blue' ><span id='var_n_explain' class='execspoff'></span></font></li></ol></ul></td></tr><tr><td></td><td align='left'><ul class='inner-table'><ol><li><font color='blue' ><span id='var_a1_disp'></span></font></li><li><span id='var_a1_inp' disp_on_off='OFF'><input size='12' type='hidden' name='var_a1' id='var_a1' value=''></span></li><li><font color='blue' ><span id='var_a1_unit'></span></font></li><li><font color='blue' ><span id='var_a1_explain' class='execspoff'></span></font></li><li><font color='blue' ><span id='var_b1_disp'></span></font></li><li><span id='var_b1_inp' disp_on_off='OFF'><input size='12' type='hidden' name='var_b1' id='var_b1' value=''></span></li><li><font color='blue' ><span id='var_b1_unit'></span></font></li><li><font color='blue' ><span id='var_b1_explain' class='execspoff'></span></font></li><li><font color='blue' ><span id='var_a2_disp'></span></font></li><li><span id='var_a2_inp' disp_on_off='OFF'><input size='12' type='hidden' name='var_a2' id='var_a2' value=''></span></li><li><font color='blue' ><span id='var_a2_unit'></span></font></li><li><font color='blue' ><span id='var_a2_explain' class='execspoff'></span></font></li><li><font color='blue' ><span id='var_b2_disp'></span></font></li><li><span id='var_b2_inp' disp_on_off='OFF'><input size='12' type='hidden' name='var_b2' id='var_b2' value=''></span></li><li><font color='blue' ><span id='var_b2_unit'></span></font></li><li><font color='blue' ><span id='var_b2_explain' class='execspoff'></span></font></li><li><font color='blue' ><span id='var_a3_disp'></span></font></li><li><span id='var_a3_inp' disp_on_off='OFF'><input size='12' type='hidden' name='var_a3' id='var_a3' value=''></span></li><li><font color='blue' ><span id='var_a3_unit'></span></font></li><li><font color='blue' ><span id='var_a3_explain' class='execspoff'></span></font></li><li><font color='blue' ><span id='var_b3_disp'></span></font></li><li><span id='var_b3_inp' disp_on_off='OFF'><input size='12' type='hidden' name='var_b3' id='var_b3' value=''></span></li><li><font color='blue' ><span id='var_b3_unit'></span></font></li><li><font color='blue' ><span id='var_b3_explain' class='execspoff'></span></font></li><li><font color='blue' ><span id='var_a4_disp'></span></font></li><li><span id='var_a4_inp' disp_on_off='OFF'><input size='12' type='hidden' name='var_a4' id='var_a4' value=''></span></li><li><font color='blue' ><span id='var_a4_unit'></span></font></li><li><font color='blue' ><span id='var_a4_explain' class='execspoff'></span></font></li><li><font color='blue' ><span id='var_b4_disp'></span></font></li><li><span id='var_b4_inp' disp_on_off='OFF'><input size='12' type='hidden' name='var_b4' id='var_b4' value=''></span></li><li><font color='blue' ><span id='var_b4_unit'></span></font></li><li><font color='blue' ><span id='var_b4_explain' class='execspoff'></span></font></li></ol></ul></td></tr><tr><td colspan='2' class='center'><input type='button' value=' 計算 ' onclick='return checkText()' class='bigbutton' id='executebtn'><input type='button' id='clearbtn' value='クリア' onclick='clearText()' class='bigbutton'><span id='graph'></span><span id='loadsavebtnarea'><input type='button' value='保存・呼出' id='loadsavebtn' onclick='loadSaveBtn(1)' class='bigbutton'></span><select name='ketasu' class='ketasu'><option value='6' >6桁</option><option value='10' >10桁</option><option value='14' >14桁</option><option value='18' >18桁</option><option value='22' >22桁</option><option value='26' >26桁</option><option value='30' >30桁</option><option value='34' >34桁</option><option value='38' >38桁</option><option value='42' >42桁</option><option value='46' selected>46桁</option><option value='50' >50桁</option></select><script> if(document.getElementById('graph') != null){document.getElementById('graph').innerHTML = "";} </script> <hr class='line'><span id='loadSaveArea'></span></td></tr><tr><td colspan='2' class='center'><span id='myGraphC'></span></td></tr><tr><td colspan=2 class='center'><div><div align='center' style='margin-top:2px;margin-bottom:3px;'><b></b></div><span id='exetb2'></span></div></td></tr><tr><td colspan=2></td></tr></table></td></tr></table></div></form><script> var calendarAr = new Array();</script><div id='exetb0' style='text-align:center'><span id='exetb' style='display:inline-block;margin-bottom:10px'></span><span id='exeright'></span></div><div class='center_container'><table class='image_d_exe' align='center'><tr><td class='center'><span id='myGraphD'></span></td></tr></table><div align='center'><span id='myGraphE'></span></div><div align='center'><table align='center' class='setumei'><tr><td align='left'>前回と今回の値が等しくなると終了します。演算桁数を大きくするとπの精度も向上します。<br /><br />17世紀の微積分学の発達で、多くの数学者がatan(x)の級数展開の手法で円周率の計算に挑戦しました。<br /><br /><center><table align=center style='max-width:100px;clear:left'><tr><td><span class='getMathWidth' style='display:none;'>\(\normalsize Gregory\ series\hspace{10px}tan^{\tiny-1}x=x-{\normalsize\frac{1}{3}}x^3+{\normalsize\frac{1}{5}}x^5-{\normalsize\frac{1}{7}}x^7+\cdot\cdot\cdot\\<br />(1)\ Gauss\ 1863\\<br />\hspace{10px}{\small{\normalsize\frac{\pi}{4}}=12tan^{\tiny-1}{\normalsize\frac{1}{38}}+20tan^{\tiny-1}{\normalsize\frac{1}{57}}+7tan^{\tiny-1}{\normalsize\frac{1}{239}}+24tan^{\tiny-1}{\normalsize\frac{1}{268}}}\\<br />(2)\ Stormer\ 1896\\<br />\hspace{10px}{\small{\normalsize\frac{\pi}{4}}=44tan^{\tiny-1}{\normalsize\frac{1}{57}}+7tan^{\tiny-1}{\normalsize\frac{1}{239}}-12tan^{\tiny-1}{\normalsize\frac{1}{682}}+24tan^{\tiny-1}{\normalsize\frac{1}{12943}}}\\<br />(3)\ Escott\ 1896\\<br />\hspace{10px}{\small{\normalsize\frac{\pi}{4}}=22tan^{\tiny-1}{\normalsize\frac{1}{28}}+2tan^{\tiny-1}{\normalsize\frac{1}{443}}-5tan^{\tiny-1}{\normalsize\frac{1}{1393}}-10tan^{\tiny-1}{\normalsize\frac{1}{11018}}}\\<br />(4)\ K.\ Takano\ 1982\\<br />\hspace{10px} {\small{\normalsize\frac{\pi}{4}}=12tan^{\tiny-1}{\normalsize\frac{1}{49}}+32tan^{\tiny-1}{\normalsize\frac{1}{57}}-5tan^{\tiny-1}{\normalsize\frac{1}{239}}+12tan^{\tiny-1}{\normalsize\frac{1}{110443}}}\\<br />(5)\ T.\ Murata\ 1982\\<br />\hspace{10px}{\small{\normalsize\frac{\pi}{4}}=24tan^{\tiny-1}{\normalsize\frac{1}{36}}+8tan^{\tiny-1}{\normalsize\frac{1}{57}}-5tan^{\tiny-1}{\normalsize\frac{1}{239}}-12tan^{\tiny-1}{\normalsize\frac{1}{23382}}}\\<br />(6)\ A.\ Shibata\ 1983\\<br />\hspace{10px}{\small{\normalsize\frac{\pi}{4}}=24tan^{\tiny-1}{\normalsize\frac{1}{43}}+20tan^{\tiny-1}{\normalsize\frac{1}{57}}-12tan^{\tiny-1}{\normalsize\frac{1}{117}}-5tan^{\tiny-1}{\normalsize\frac{1}{239}}}\\\)</span></td></tr></table></center></td></tr></table></div><div align='center'><table id='rlink' cellpadding='0' cellspacing='0'><tr><td class='caption'>関連リンク</td></tr><tr><td class='body'><a href='http://www5f.biglobe.ne.jp/~tsuushin/sub1d.html' target=_blank>πのarctangent公式集</a></td></tr></table></div></div></div>  <div id='questionnaire'><ul class='tab-title cf'></ul><div class='tabs' id='quest-tabs'><ul class='tab-title cf'><li class='tab-voice'><div><img src='/keisan/pc/common/img/ico_voice.png' alt='' /><a href='#voice' onclick='_tabpc = 1;readAnketo(0)'><span>お客様の声</span></a></div></li><li class='tab-enq'><div><img src='/keisan/pc/common/img/ico_enq.png' alt='' /><a href='#enq' onclick='ankset();'><span>アンケート投稿</span></a></div></li><li class='tab-faq'><div><img src='/keisan/pc/common/img/ico_faq.png' alt='' /><a href='#faq' onclick='frqask()'><span>よくある質問</span></a></div></li><li class='tab-link'><div><img src='/keisan/pc/common/img/ico_link.png' alt='' /><a href='#link' onclick='linkset();'><span>リンク方法</span></a></div></li></ul><div id='voice' class='tab-contents'><span class="top"><div class="col-nav"><div class="title">円周率計算（ATAN 4項級数）</div><table class=page><tr><td class=count>[0-0] / 0件</td><td class=readcount>表示件数<select name=ank_read_cnt id=ank_read_cnt><option value=5>5<option selected value=10>10<option value=30>30<option value=50>50<option value=100>100<option value=200>200</select><td class=bnbtn><div class=bnbtn><img src="/keisan/pc/common/img/btn_back_none.gif" alt="BACK" /> <img src="/keisan/pc/common/img/btn_next_none.gif" alt="NEXT" /></div></td></tr></table><script>$j(function(){$j("#ank_read_cnt").change(function(){readAnketo(0)})})</script></div></span><div class="col">メッセージは１件も登録されていません。</div><br><span class="top"><div class="col-nav col-nav-btm"><div class=bnbtn><img src="/keisan/pc/common/img/btn_back_none.gif" alt="BACK" /> <img src="/keisan/pc/common/img/btn_next_none.gif" alt="NEXT" /></div></div></span></div><div id='enq' class='tab-contents'><span id='thanskank'><div class='col'><p class='comp'>アンケートにご協力頂き有り難うございました。<br><br>送信を完了しました。</p><br><br><p class='comp'><a onclick='dispank()'><img src='/keisan/pc/common/img/btn_back.gif' alt='Back' class='hov' /></a></p></div></span><span id='anks'><div class='col-title'><b>【円周率計算（ATAN 4項級数）】のアンケート記入欄</b></div><form name='bug'><input type='hidden' name='command' value='regist'><input type='hidden' name='charset' value='utf-8'><input type='hidden' name='libnum' id='libnum'><input type='hidden' name='libname2' id='libname2'><input type='hidden' name='lang' value=''><input type='hidden' name='uc_k3' value=''><div class='col'><dl><dt>年齢</dt><dd><input type='radio' name='age' class='kradio' id='age01' value='20歳未満' ><label class='radiolabel' for='age01' onclick='radioSel("age", "20歳未満")'>20歳未満</label><input type='radio' name='age' class='kradio' id='age02' value='20歳代' ><label class='radiolabel' for='age02' onclick='radioSel("age", "20歳代")'>20歳代</label><input type='radio' name='age' class='kradio' id='age03' value='30歳代' ><label class='radiolabel' for='age03' onclick='radioSel("age", "30歳代")'>30歳代</label><input type='radio' name='age' class='kradio' id='age04' value='40歳代' ><label class='radiolabel' for='age04' onclick='radioSel("age", "40歳代")'>40歳代</label><input type='radio' name='age' class='kradio' id='age05' value='50歳代' ><label class='radiolabel' for='age05' onclick='radioSel("age", "50歳代")'>50歳代</label><input type='radio' name='age' class='kradio' id='age06' value='60歳以上' ><label class='radiolabel' for='age06' onclick='radioSel("age", "60歳以上")'>60歳以上</label></dd></dl><dl><dt>職業</dt><dd><input type='radio' name='work' class='kradio' id='work01' value='小・中学生' ><label class='radiolabel' for='work01' onclick='radioSel("work", "小・中学生")'>小・中学生</label><input type='radio' name='work' class='kradio' id='work02' value='高校・専門・大学生・大学院生' ><label class='radiolabel' for='work02' onclick='radioSel("work", "高校・専門・大学生・大学院生")'>高校・専門・大学生・大学院生</label><input type='radio' name='work' class='kradio' id='work03' value='主婦' ><label class='radiolabel' for='work03' onclick='radioSel("work", "主婦")'>主婦</label><input type='radio' name='work' class='kradio' id='work04' value='会社員・公務員' ><label class='radiolabel' for='work04' onclick='radioSel("work", "会社員・公務員")'>会社員・公務員</label><br><input type='radio' name='work' class='kradio' id='work05' value='自営業' ><label class='radiolabel' for='work05' onclick='radioSel("work", "自営業")'>自営業</label><input type='radio' name='work' class='kradio' id='work06' value='エンジニア' ><label class='radiolabel' for='work06' onclick='radioSel("work", "エンジニア")'>エンジニア</label><input type='radio' name='work' class='kradio' id='work07' value='教師・研究員' ><label class='radiolabel' for='work07' onclick='radioSel("work", "教師・研究員")'>教師・研究員</label><input type='radio' name='work' class='kradio' id='work09' value='その他' ><label class='radiolabel' for='work09' onclick='radioSel("work", "その他")'>その他</label></dd></dl><dl><dt>この計算式は</dt><dd><input type='radio' name='useful' class='kradio' id='useful01' value='非常に役に立った' ><label class='radiolabel' for='useful01' onclick='radioSel("useful", "非常に役に立った")'>非常に役に立った</label><input type='radio' name='useful' class='kradio' id='useful02' value='役に立った' ><label class='radiolabel' for='useful02' onclick='radioSel("useful", "役に立った")'>役に立った</label><br><input type='radio' name='useful' class='kradio' id='useful03' value='少し役に立った' ><label class='radiolabel' for='useful03' onclick='radioSel("useful", "少し役に立った")'>少し役に立った</label><input type='radio' name='useful' class='kradio' id='useful04' value='役に立たなかった' ><label class='radiolabel' for='useful04' onclick='radioSel("useful", "役に立たなかった")'>役に立たなかった</label></dd></dl><dl class='text'><dt>使用目的</dt><dd><TEXTAREA name='purpose' id='purpose'></TEXTAREA></dd></dl><dl class='text'><dt><span id='chgank'>ご意見・ご感想・ご要望（バグ報告は<a onclick='changebug()'><font color='red'>こちら</font></a>) <input type='radio' name='content_flag' value='0' checked style='display:none'></span><span id='chgbug'>バグに関する報告 (ご意見・ご感想・ご要望は<a onclick='changeanketo();'><font color='red'>こちら</font></a>）<br /><input type='radio' name='content_flag' value='1'>計算バグ(入力値と間違ってる結果、正しい結果、参考資料など)<br /><input type='radio' name='content_flag' value='2'>説明バグ(間違ってる説明文と正しい説明文など) <br /> </span></dt><dd><textarea name='bodytext' id='bodytext' ></textarea></dd></dl><div class='btn-center'>アンケートは下記にお客様の声として掲載させていただくことがあります。<br /><img src='/keisan/pc/common/img/btn_send.gif' alt='送信' class='hov' onclick='submitank()' /></div></div></form></span></div><div id='faq' class='tab-contents'></div><div id='link' class='tab-contents'> <div class='col'> <dl> <dt><b>【円周率計算（ATAN 4項級数）にリンクを張る方法】</b></dt> <dd><textarea style='height:50px;margin-bottom:10px;'><a href="https://keisan.casio.jp/exec/system/1258598283">円周率計算（ATAN 4項級数）</a></textarea></dd> </dl> <span id='linkset'></span> </div></div></div></div></div> <div id='footer-nav' class='cf'><ol class='bread-crumbs'><li><a href='/'>ホーム</a></li><span id='allimage'></span><li> / <a href='/menu/system/000000000780'>計算応用集</a></li><li> / <a href='/menu/system/000000000820'>円周率計算</a></li></ol><p class='pagetop'><a href='#wrap'>このページの先頭へ</a></p></div></div><div id='side-contents'><div class='side-box'><h3 class='title'><img src='/keisan/pc/common/img/bookmark.gif' alt='' />ブックマーク</h3><ul class='link-arw5' id='favorite'></ul><div id='bookmark'></div></div><div class='side-classpad_box'><a href='//casio.link/3qI9c2B'><img src='/keisan/image/contents_pc.jpg' alt='' /></a></div><div class='side-classpad_box'><a href='//casio.link/3LvzoVx'><img src='/keisan/image/classpad_pc1.jpg' alt='' /></a></div><div class='side-box'><h3 class='title'><img src='/keisan/pc/common/img/hist.gif' alt='' /> 実行履歴</h3><ul class='link-arw2'><div id='hist'></div></ul></div></div></div><script>function googleMppAlert(){ alert('Google Mapを表示する機能は廃止になりました。'); } exedata = [["回数","円周率π 近似"],[,,]];addTableClass('#e6f2ff','black','transparence','black','center');addTableClass('#e6f2ff','black','transparence','black','left');dispExecData();setDispValue('ATANformula4.csv', '12 38 20 57 7 239 24 268 <math>\\normalsize {\\large\\frac{\\pi}{4}}=12tan^{\\tiny-1}{\\large\\frac{1}{38}}+20tan^{\\tiny-1}{\\large\\frac{1}{57}}+7tan^{\\tiny-1}{\\large\\frac{1}{239}} \\\\\\hspace{180px} +24tan^{\\tiny-1}{\\large\\frac{1}{268}}\\\\</math>|1', '公式,,,a1|a1,b1|b1,a2|a2,b2|b2,a3|a3,b3|b3,a4|a4,b4|b4,remark|rm'); var isSearchEnjin = 0;libcate='計算応用集/円周率計算/円周率計算（ATAN 4項級数）';var libname='円周率計算（ATAN 4項級数）';var libnamesv='円周率計算（ATAN 4項級数）';lang='';function excelToInput(){}function inputToExcel(){}function clearText(){if(window.document.getElementById('libname') != null){ window.document.getElementById('libname').value = ''; libNameClearCookie(); } if('' != ''){return;} if(document.calc.var_rm.type != 'hidden'){document.calc.var_rm.value = '';}nextFocus();}function firstExec(){ if(! '' ){checkText();} }function checkText(){ if('' != ''){return false;} if(document.calc.var_rm.type != 'hidden'){var chkinp=cutcomma(document.calc.var_rm.name ); if(chkinp == null || chkinp == false){document.calc.var_rm.focus();return false;}} libNameSaveCookie(); uniqueCookieID(); document.calc.action = '/exec/system/1258598283'; document.calc.target = '_self'; document.calc.method = 'post'; document.calc.submit(); return true;}function onLoadfunc(){ execLoad();}paramSR = new Array();sysUserCode = 'system/1258598283';paramSR.push("var_rm::TXT");paramSR.push("var_f:1:SEL");paramSR.push("var_n::TXT");paramSR.push("var_a1::TXT");paramSR.push("var_b1::TXT");paramSR.push("var_a2::TXT");paramSR.push("var_b2::TXT");paramSR.push("var_a3::TXT");paramSR.push("var_b3::TXT");paramSR.push("var_a4::TXT");paramSR.push("var_b4::TXT");function random(){}function nextFocus(){ if(document.calc.var_rm.value == '' && document.calc.var_rm.type != 'hidden' ){ document.calc.var_rm.focus();return; }}nextFocus();</script><br><div id="footer"> <div class="menu"> <ul class="link-arw1"> <li><a href="https://www.casio.co.jp/privacy/">プライバシーポリシー</a></li> <li><a href="/keisan/kiyaku.php">サービス規約</a></li> <li><a href="/keisan/faq.php">よくある質問</a></li> <li><a href="/keisan/output.php">外部送信について</a></li> <li><a href="/keisan/toiawase.php">お問い合わせ</a></li> </ul> </div> <p class="copy">© 2024 CASIO COMPUTER CO., LTD.<a href="https://www.casio.co.jp/"><img src="/keisan/pc/common/img/logo_casio.gif" alt="CASIO" /></a></p></div><?// TOP pageは直接記述$uri = $_SERVER['REQUEST_URI'];if( $uri != "/index.php" && $uri != "/"){?><noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-KDTHSZ" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript><script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='//www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-KDTHSZ');</script><?}?></body></html>