{"id":1429,"date":"2021-10-04T11:56:02","date_gmt":"2021-10-04T02:56:02","guid":{"rendered":"http:\/\/www.miyamoto-lab.com\/?p=1429"},"modified":"2022-10-02T12:12:53","modified_gmt":"2022-10-02T03:12:53","slug":"18gsdfgh34a","status":"publish","type":"post","link":"https:\/\/www.miyamoto-lab.com\/ja\/2021\/10\/04\/18gsdfgh34a\/","title":{"rendered":"4. \u9023\u7acb\u5e38\u5fae\u5206\u65b9\u7a0b\u5f0f\u306e\u89e3\u6cd5"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">\uff08\u4ee5\u4e0b\u3067\u306f\u4f8b\u306b\u3088\u3063\u3066\u3001\u958b\u767a\u74b0\u5883\u304c\u624b\u5143\u306b\u306a\u3044\u5834\u5408\u306f\u3001<a href=\"https:\/\/www.codechef.com\/ide\"><\/a><a href=\"https:\/\/paiza.io\/ja\/projects\/new?language=c\">paiza.io<\/a>,&nbsp;<a href=\"https:\/\/www.onlinegdb.com\/online_c_compiler\">onlineGDB<\/a>,&nbsp;<a href=\"https:\/\/www.programiz.com\/c-programming\/online-compiler\/\">programiz,&nbsp;<\/a><a href=\"https:\/\/www.codechef.com\/ide\">codechef.com<\/a>,&nbsp;<a href=\"https:\/\/ideone.com\/\">ideone.com<\/a>,&nbsp;<a href=\"https:\/\/paiza.io\/\">paiza.io<\/a>\u306a\u3069\u3092\u5b9f\u884c\u3057\u3066\u307f\u308b\u3068\u826f\u3044\uff09<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u9023\u7acb\u5e38\u5fae\u5206\u65b9\u7a0b\u5f0f\u3082\u3001\u540c\u69d8\u306e\u624b\u6cd5\u3067\u89e3\u304f\u3053\u3068\u304c\u3067\u304d\u308b\u3002\u305f\u3068\u3048\u3070\u751f\u7269\u306e\u6355\u98df\u2015\u88ab\u98df\u95a2\u4fc2\u306b\u304a\u3051\u308b\u500b\u4f53\u6570\u306e\u5909\u52d5\u3092\u8868\u73fe\u3059\u308b\u6570\u7406\u30e2\u30c7\u30eb\u306b\u3001\u30ed\u30c8\u30ab\u30fb\u30f4\u30a9\u30eb\u30c6\u30e9\u306e\u65b9\u7a0b\u5f0f\u304c\u3042\u308b\u3002\u6355\u98df\u8005\uff08\u305f\u3068\u3048\u3070\u30e4\u30de\u30cd\u30b3\uff09\u306e\u500b\u4f53\u6570$x$\u304c\u3001\u88ab\u98df\u8005\uff08\u305f\u3068\u3048\u3070\u30a6\u30b5\u30ae\uff09\u306e\u500b\u4f53\u6570$y$\u3068\u304c\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a2\u5143\u9023\u7acb\u975e\u7dda\u5f62\u5e38\u5fae\u5206\u65b9\u7a0b\u5f0f\u306e\u95a2\u4fc2\u3067\u3042\u3089\u308f\u3055\u308c\u308b\u3068\u3059\u308b\u8003\u3048\u65b9\u3067\u3042\u308b\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">$$\\frac{dx}{dt}=ax &#8211; cxy$$<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">$$\\frac{dy}{dt}=-by+cxy$$<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u3046\u3057\u305f\u9023\u7acb\u5fae\u5206\u65b9\u7a0b\u5f0f\u3067\u3042\u3063\u3066\u3082\u3001\u540c\u69d8\u306b\u30eb\u30f3\u30b2\u30fb\u30af\u30c3\u30bf\u6cd5\u3092\u9069\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u73fe\u5b9f\u7684\u306b\u89e3\u304f\u3053\u3068\u304c\u3067\u304d\u308b\u3002\u3084\u308a\u65b9\u3068\u3057\u3066\u306f\u540c\u3058\u3060\u304c<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">$$\\frac{dx}{dt}=f(t,x,y)$$<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">$$\\frac{dy}{dt}=g(t,x,y)$$<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3068\u6574\u7406\u3057\u3066\u3001\u5404\u3005\u306b1\u6bb5\u305a\u3064\u30eb\u30f3\u30b2\u30af\u30c3\u30bf\u6cd5\u3092\u9069\u7528\u3057\u3066\u3044\u3051\u3070\u3088\u3044\u3002\u3059\u306a\u308f\u3061\u3001<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">$$\\begin{matrix}k_{x1}=hf(t_i,x_i,y_i) &amp; k_{y1}=hg(t_i,x_i,y_i)\\\\k_{x2}=hf(t_i+\\frac{h}{2},x_i+\\frac{k_{x1}}{2},y_i+\\frac{k_{y1}}{2})&amp;k_{y2}=hg(t_i+\\frac{h}{2},x_i+\\frac{k_{x1}}{2},y_i+\\frac{k_{y1}}{2}) \\\\k_{x3}=hf(t_i+\\frac{h}{2},x_i+\\frac{k_{x2}}{2},y_i+\\frac{k_{y2}}{2})&amp;k_{y3}=hg(t_i+\\frac{h}{2},x_i+\\frac{k_{x2}}{2},y_i+\\frac{k_{y2}}{2})\\\\k_{x4}=hf(t_i+h,x_i+k_{x3},y_i+k_{y3}) &amp;k_{y4}=hg(t_i+h,x_i+k_{x3},y_i+k_{y3})\\end{matrix}$$<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3068\u3057\u3066\u9806\u6b21\u8a08\u7b97\u3057\u3001<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">$$x_{i+1}=x_i+\\frac{1}{6}(k_{x1}+2k_{x2}+2k_{x3}+k_{x4})$$<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">$$y_{i+1}=y_i+\\frac{1}{6}(k_{y1}+2k_{y2}+2k_{y3}+k_{y4})$$<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3068\u3057\u3066\u6b21\u306e\u30b9\u30c6\u30c3\u30d7\u306e $x, y$\u3092\u8a08\u7b97\u3057\u3066\u3044\u3051\u3070\u3088\u3044\u3002\u4e00\u898b\u8907\u96d1\u306b\u898b\u3048\u308b\u304c\u3001\u3084\u3063\u3066\u3044\u308b\u3053\u3068\u306f\u6975\u3081\u3066\u5358\u7d14\u3067\u3001\u3053\u308c\u3092\u30d7\u30ed\u30b0\u30e9\u30e0\u306b\u3059\u308b\u3068<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-c\" data-lang=\"C\"><code>#include &lt;stdio.h&gt;\n#include &lt;math.h&gt;\n#define N 1000\n#define h 1.0\ndouble f(double t,double x, double y);\ndouble g(double t,double x, double y);\nint main(void) {\n  int i;\n  double x=1000.0;\n  double y=100.0;\n  double t=0.0;\n  double kx1,ky1,kx2,ky2,kx3,ky3,kx4,ky4;\n  for (i = 0; i &lt; N; i++) {\n    kx1=\uff08\u3053\u3053\u306b\u8a18\u8ff0\u3059\u308b\uff09; ky1=\uff08\u3053\u3053\u306b\u8a18\u8ff0\u3059\u308b\uff09;\n    kx2=\uff08\u3053\u3053\u306b\u8a18\u8ff0\u3059\u308b\uff09; ky2=\uff08\u3053\u3053\u306b\u8a18\u8ff0\u3059\u308b\uff09;\n    kx3=\uff08\u3053\u3053\u306b\u8a18\u8ff0\u3059\u308b\uff09; ky3=\uff08\u3053\u3053\u306b\u8a18\u8ff0\u3059\u308b\uff09;\n    kx4=\uff08\u3053\u3053\u306b\u8a18\u8ff0\u3059\u308b\uff09; ky4=\uff08\u3053\u3053\u306b\u8a18\u8ff0\u3059\u308b\uff09;\n    x=\uff08\u3053\u3053\u306b\u8a18\u8ff0\u3059\u308b\uff09\n    y=\uff08\u3053\u3053\u306b\u8a18\u8ff0\u3059\u308b\uff09\n    t=t+h;\n    printf(&quot;%4.4lf\\t %4.4lf\\t %e\\n&quot;,x,y,t);\n    }\n}\ndouble f(double t,double x, double y) {\n  return (0.01*x-0.00001*x*y);\n}\ndouble g(double t,double x, double y) {\n  return (-0.02*y+0.00001*x*y);\n}\n\n<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u306e\u3088\u3046\u306b\u66f8\u304f\u3053\u3068\u304c\u3067\u304d\u308b\u3002\u3053\u306e\u7d50\u679c\u304c<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">1009.0456 99.0095 0<br>1018.1831 98.0376 1<br>1027.4132 97.0843 2<br>1036.7367 96.1491 3<br>1046.1546 95.2318 4<br>1055.6675 94.3323 5<br>1065.2765 93.4501 6<br>1074.9824 92.5852 7<br>1084.7859 91.7372 8<br>1094.6881 90.9059 9<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u306e\u3088\u3046\u306b\u306a\u3063\u3066\u3044\u308c\u3070\u3001\u8a08\u7b97\u306f\u3067\u304d\u3066\u3044\u308b\u30021000\u56de\u304f\u3089\u3044\u7e70\u308a\u8fd4\u3059\u3068\u3001<\/p>\n\n\n\n<figure class=\"wp-block-image size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.miyamoto-lab.com\/wp-content\/uploads\/2020\/09\/rg3.png\" alt=\"\" class=\"wp-image-291\" width=\"521\" height=\"228\" srcset=\"https:\/\/www.miyamoto-lab.com\/wp-content\/uploads\/2020\/09\/rg3.png 694w, https:\/\/www.miyamoto-lab.com\/wp-content\/uploads\/2020\/09\/rg3-300x131.png 300w\" sizes=\"auto, (max-width: 521px) 100vw, 521px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u306e\u3088\u3046\u306a\u990c\u3068\u6355\u98df\u8005\u306e\u5909\u52d5\u306e\u5468\u671f\u7684\u306a\u95a2\u4fc2\u3092\u898b\u308b\u3053\u3068\u304c\u3067\u304d\u308b\uff08\u30e2\u30c7\u30eb\u3084\u30d1\u30e9\u30e1\u30bf\u306e\u554f\u984c\u70b9\u306f\u8b70\u8ad6\u3057\u306a\u3044\uff09\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u3067\u5e38\u5fae\u5206\u65b9\u7a0b\u5f0f\u306b\u57fa\u3065\u3044\u305f\u3001\u3055\u307e\u3056\u307e\u306a\u7269\u7406\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3\u3092\u5b9f\u65bd\u3059\u308b\u305f\u3081\u306e\u57fa\u790e\u7684\u306a\u77e5\u8b58\u306f\u8eab\u306b\u4ed8\u3044\u305f\u3002\u306a\u304a\u3001\u4e0a\u8a18\u306e\u30b3\u30fc\u30c9\u306f\u3001\u30dd\u30a4\u30f3\u30bf\u306e\u6982\u5ff5\u3092\u4f7f\u3048\u3070\u95a2\u6570\u306e\u8aad\u307f\u51fa\u3057\u306e\u90e8\u5206\u3067\u65ad\u7136\u7c21\u7d20\u5316\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u308b\u306e\u3067\u3001\u8208\u5473\u306e\u3042\u308b\u4eba\u306f\u3084\u3063\u3066\u307f\u3088\u3046\u3002<br><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u4eca\u9031\u306e\u8ab2\u984c<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u8ab2\u984c\u306f\u8b1b\u7fa9\u4e2d\u306b\u3084\u3063\u3066\u3082\u3089\u3046\u3053\u3068\u3092\u60f3\u5b9a\u3057\u3066\u3044\u307e\u3059\u3001\u4ee5\u4e0b\u306b\u3064\u3044\u3066\u56de\u7b54\u3057\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002\u30aa\u30ea\u30b8\u30ca\u30ea\u30c6\u30a3\u304c\u9ad8\u3044\u56de\u7b54\u307b\u3069\u9ad8\u8a55\u4fa1\u3067\u3001\u304a\u306a\u3058\u30aa\u30ea\u30b8\u30ca\u30ea\u30c6\u30a3\u3067\u3042\u308c\u3070\u63d0\u51fa\u6642\u9593\u304c\u65e9\u3044\u307b\u3069\u9ad8\u8a55\u4fa1\u3002\u63d0\u51fa\u306f10\/10 \u6df1\u591c\u307e\u3067\u3002\u63d0\u51fa\u304c\u9045\u304f\u3066\u3082\u30aa\u30ea\u30b8\u30ca\u30ea\u30c6\u30a3\u304c\u975e\u5e38\u306b\u9ad8\u3044\u3082\u306e\u304c\u6700\u9ad8\u8a55\u4fa1\u3001\u3068\u3057\u307e\u3059\u3002\u63d0\u51fa\u306fITC\u3067\u306f\u306a\u304f\u3066\u3001<a href=\"https:\/\/forms.gle\/5SAxcgPD1kkkKZ7w9\">https:\/\/forms.gle\/5SAxcgPD1kkkKZ7w9<\/a> \u306b\u304a\u9858\u3044\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u30eb\u30f3\u30b2\u30af\u30c3\u30bf\u306e\uff14\u6b21\u516c\u5f0f\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u3082\u306e\u3067\u3042\u3063\u305f\uff1a<\/p>\n\n\n\n<p class=\"has-pale-cyan-blue-background-color has-background wp-block-paragraph\">\u5fae\u5206\u65b9\u7a0b\u5f0f$\\frac{dy}{dx}=f(x,y)$ \u306b\u5bfe\u3057\u3001\u521d\u671f\u6761\u4ef6$y(x_0)=y_0$\u3068\u3057\u305f\u3068\u304d\u306e\u6570\u5024\u89e3\u306f\u3001\u523b\u307f\u5e45\u3092$h$\u3068\u3057\u3066\u3001$x_n=x_0+nh$\u306b\u304a\u3051\u308b$y$\u306e\u5024\u3092$y_n$\u304b\u3089$y_{n+1}=y_n+k$\u3068\u66f8\u304f\u5834\u5408\u3001$k$\u306f\u4ee5\u4e0b\u3067\u8fd1\u4f3c\u3067\u304d\u308b<br>$$\\begin{array}{ccc}k_1 &amp; = &amp; hf(x_n, y_n)\\\\k_2 &amp; = &amp; hf \\left ( x_n+\\frac{h}{2},y_n+\\frac{k_1}{2}\\right )\\\\k_3 &amp; = &amp; hf \\left ( x_n+\\frac{h}{2},y_n+\\frac{k_2}{2}\\right )\\\\k_4&amp;=&amp;hf(x_n+h,y_n+k_3)\\\\k&amp;=&amp;\\frac{1}{6}(k_1+2k_2+2k_3+k_4) \\end{array}$$<\/p>\n\n\n\n<p class=\"has-pale-cyan-blue-background-color has-background wp-block-paragraph\">\u9023\u7acb\u5fae\u5206\u65b9\u7a0b\u5f0f<br>$$\\left \\{ \\begin{array}{ccc}\\frac{dy}{dx} &amp;=&amp;f(x,y,z),&amp;\u521d\u671f\u6761\u4ef6\u304c&amp; y(x_0)=y_0\\\\\\frac{dz}{dx} &amp;=&amp;g(x,y,z),&amp;\u521d\u671f\u6761\u4ef6\u304c&amp; z(x_0)=z_0 \\end{array} \\right .$$<br>\u306e\u6570\u5024\u89e3\u306f\u3001\u523b\u307f\u5e45\u3092$h$\u3001$x_n=x_0+nh$\u3068\u3057\u3066\u4ee5\u4e0b\u3067\u4e0e\u3048\u3089\u308c\u308b\uff1a<br>$$\\begin{array}{ccc}k_1 &amp; = &amp; hf(x_n, y_n, z_n)\\\\l_1 &amp; = &amp; hg(x_n, y_n, z_n)\\\\k_2 &amp; = &amp; hf \\left ( x_n+\\frac{h}{2},y_n+\\frac{k_1}{2},z_n+\\frac{l_1}{2}\\right )\\\\l_2 &amp; = &amp; hg \\left ( x_n+\\frac{h}{2},y_n+\\frac{k_1}{2},z_n+\\frac{l_1}{2}\\right )\\\\k_3 &amp; = &amp; hf \\left ( x_n+\\frac{h}{2},y_n+\\frac{k_2}{2},z_n+\\frac{l_2}{2}\\right )\\\\l_3 &amp; = &amp; hg \\left ( x_n+\\frac{h}{2},y_n+\\frac{k_2}{2},z_n+\\frac{l_2}{2}\\right )\\\\k_4&amp;=&amp;hf(x_n+h,y_n+k_3, z_n+l_3)\\\\l_4&amp;=&amp;hg(x_n+h,y_n+k_3, z_n+l_3)\\\\k&amp;=&amp;\\frac{1}{6}(k_1+2k_2+2k_3+k_4)\\\\l&amp;=&amp;\\frac{1}{6}(l_1+2l_2+2l_3+l_4) \\\\y_{n+1}&amp;=&amp;y_n+k\\\\z_{n+1}&amp;=&amp;z_n+l\\end{array} $$<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0a\u306e\u8003\u3048\u65b9\u3092\u4f7f\u3063\u3066\u3001\u4ee5\u4e0b\u306e\u554f\u984c\u3092\u89e3\u3044\u3066\u307f\u3088\u3046<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8ab2\u984c1\uff1a$y^\\prime =y-10x +1$\u3092\u523b\u307f\u5e450.1\u3067$x=0$\u304b\u3089$x=1.0$\u307e\u3067\u89e3\u3051\u3002\u305f\u3060\u3057\u521d\u671f\u6761\u4ef6\u3092$y(0)=1$\u3068\u3059\u308b\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8ab2\u984c\uff12\uff1a2\u968e\u5fae\u5206\u65b9\u7a0b\u5f0f$\\frac{d^2 y}{dx^2}-2x\\frac{dy}{dx}+xy=0$\u3092\u521d\u671f\u6761\u4ef6$y(0)=1, y^\\prime(0)=1$\u3067\u89e3\u3051\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8ab2\u984c3: \u91ce\u7403\u30dc\u30fc\u30eb\u304c\u3069\u3053\u307e\u3067\u98db\u3076\u304b\u8003\u3048\u3088\u3002\u305f\u3060\u3057\u7a7a\u6c17\u62b5\u6297\u304c\u901f\u5ea6\u306e2\u4e57\u306b\u6bd4\u4f8b\u3059\u308b\u4ee5\u4e0b\u306e\u5f62\u3067\u66f8\u3051\u308b\u3068\u3059\u308b\u3002<br>$$\\begin{array}{ccc}a_x&amp;=&amp;-\\frac{3}{4D}\\frac{\\rho_{air}}{\\rho_{ball}} C_d V V_x\\\\a_y&amp;=&amp;-g-\\frac{3}{4D}\\frac{\\rho_{air}}{\\rho_{ball}}C_d V V_y \\\\V&amp;=&amp;\\sqrt{V_x^2+V_y^2}\\end{array}$$<br>\u3053\u3053\u3067$a_x$\u3092\u6c34\u5e73\u65b9\u5411\u306e\u52a0\u901f\u5ea6\u3001$a_y$\u3092\u5782\u76f4\u65b9\u5411\u306e\u52a0\u901f\u5ea6\u3001$D$\u3092\u30dc\u30fc\u30eb\u306e\u76f4\u5f84=7[cm]\u3001$g$\u3092\u91cd\u529b\u52a0\u901f\u5ea6=9.8[m\/s$^2$]\u3001$\\rho_{air}$\u3092\u7a7a\u6c17\u306e\u5bc6\u5ea6=1.2[kg\/m$^3$]\u3001$\\rho_{ball}$\u3092\u30dc\u30fc\u30eb\u306e\u5bc6\u5ea6=650[kg\/m$^3$]\u3001$C_d$\u3092\u62b5\u6297\u4fc2\u6570=0.2\u3068\u3059\u308b\u3002\u521d\u901f\u309250[m\/s]\u3001\u30d0\u30c3\u30c8\u3067\u6253\u3063\u305f\u5834\u6240\u304c\u9ad8\u30551.0[m]\u3067\u3042\u308b\u5834\u5408\u300145\u5ea6\u3067\u98db\u3073\u51fa\u3059\u6642\u304c\u6700\u5927\u8ddd\u96e2\u3067\u306f\u306a\u3044\u3053\u3068\u3092\u4f55\u3089\u304b\u306e\u5f62\u3067\u793a\u305b\u3002\u306a\u304a\u30dc\u30fc\u30eb\u306e\u56de\u8ee2\u306b\u3088\u308b\u63da\u529b\u3084\u3001\u98a8\u306a\u3069\u7a7a\u6c17\u306e\u63fa\u3089\u304e\u306f\u8003\u3048\u306a\u3044\u3002<br>\u306a\u304a\u3001\u4ee5\u4e0b\u306e\u30b3\u30fc\u30c9\u3092\u53c2\u8003\u306b\u3057\u3066\u3082\u826f\u3044\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-c\" data-lang=\"C\"><code>#include &lt;stdio.h&gt;\n#include &lt;stdlib.h&gt;\n#include &lt;math.h&gt;\n#define N 1000\n#define h 0.01\ndouble G=-9.8;\ndouble k=-0.00396;\ndouble f(double t,double x, double y);\ndouble g(double t,double x, double y);\nint main(void) {\n  int i;\n  double v=50.;\n  double degree=38.;\n  double radian=degree*3.141592\/180.0;\n  double x=v*cos(radian);\n  double y=v*sin(radian);\n  double t=0.0;\n  double xx=0.,yy=1.0;\n  double vx, vy,x1,x2,x3,x4,y1,y2,y3,y4;\n  double kx1,ky1,kx2,ky2,kx3,ky3,kx4,ky4;\n  for (i = 0; i &lt; N; i++) {\n    x1=\u3053\u3053\u306b\u8a18\u8ff0;y1=\u3053\u3053\u306b\u8a18\u8ff0;\n    kx1=\u3053\u3053\u306b\u8a18\u8ff0;\u3053\u3053\u306b\u8a18\u8ff0;\n    vx=\u3053\u3053\u306b\u8a18\u8ff0;\u3053\u3053\u306b\u8a18\u8ff0;\n    x2=\u3053\u3053\u306b\u8a18\u8ff0;y2=\u3053\u3053\u306b\u8a18\u8ff0;\n    kx2=\u3053\u3053\u306b\u8a18\u8ff0;ky2=\u3053\u3053\u306b\u8a18\u8ff0;\n    vx=\u3053\u3053\u306b\u8a18\u8ff0;vy=\u3053\u3053\u306b\u8a18\u8ff0;\n    x3=\u3053\u3053\u306b\u8a18\u8ff0;y3=\u3053\u3053\u306b\u8a18\u8ff0;                  \n    kx3=\u3053\u3053\u306b\u8a18\u8ff0;ky3=\u3053\u3053\u306b\u8a18\u8ff0;\n    vx=\u3053\u3053\u306b\u8a18\u8ff0;vy=\u3053\u3053\u306b\u8a18\u8ff0;\n    x4=\u3053\u3053\u306b\u8a18\u8ff0;y4=\u3053\u3053\u306b\u8a18\u8ff0;\n    kx4=\u3053\u3053\u306b\u8a18\u8ff0;ky4=\u3053\u3053\u306b\u8a18\u8ff0;\n    xx=\u3053\u3053\u306b\u8a18\u8ff0;\n    yy=\u3053\u3053\u306b\u8a18\u8ff0;    \n    x=\u3053\u3053\u306b\u8a18\u8ff0;\n    y=\u3053\u3053\u306b\u8a18\u8ff0;\n    t=t+h;\n    if (yy&lt;0.0){\n      printf(&quot;max=%4.1lfm\\t%4.4lf\\t %4.4lf\\t %e\\t %4.4e\\t %4.4e\\n&quot;,xx,x,y,t,xx,yy);\n      exit(0);\n    }\n  }\n}\ndouble f(double t,double x, double y) {\n  return (k*sqrt(x*x+y*y)*x);\n}\ndouble g(double t,double x, double y) {\n  return (G+k*sqrt(x*x+y*y)*y);\n}<\/code><\/pre><\/div>\n","protected":false},"excerpt":{"rendered":"<p>\uff08\u4ee5\u4e0b\u3067\u306f\u4f8b\u306b\u3088\u3063\u3066\u3001\u958b\u767a\u74b0\u5883\u304c\u624b\u5143\u306b\u306a\u3044\u5834\u5408\u306f\u3001paiza.io,&nbsp;onlineGDB,&nbsp;programiz,&nbsp;codechef.com,&nbsp;ideone.com,&nbsp;pa [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_locale":"ja","_original_post":"http:\/\/www.miyamoto-lab.com\/?p=1429","footnotes":""},"categories":[1],"tags":[],"class_list":["post-1429","post","type-post","status-publish","format-standard","hentry","category-uncategorized","ja"],"_links":{"self":[{"href":"https:\/\/www.miyamoto-lab.com\/wp-json\/wp\/v2\/posts\/1429","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.miyamoto-lab.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.miyamoto-lab.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.miyamoto-lab.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.miyamoto-lab.com\/wp-json\/wp\/v2\/comments?post=1429"}],"version-history":[{"count":11,"href":"https:\/\/www.miyamoto-lab.com\/wp-json\/wp\/v2\/posts\/1429\/revisions"}],"predecessor-version":[{"id":1670,"href":"https:\/\/www.miyamoto-lab.com\/wp-json\/wp\/v2\/posts\/1429\/revisions\/1670"}],"wp:attachment":[{"href":"https:\/\/www.miyamoto-lab.com\/wp-json\/wp\/v2\/media?parent=1429"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.miyamoto-lab.com\/wp-json\/wp\/v2\/categories?post=1429"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.miyamoto-lab.com\/wp-json\/wp\/v2\/tags?post=1429"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}