定积分定义动画演示

402

Clear[f, x, a, b];
- M% `/ Y: Z# @& {& b1 g  df[x_]： = x^2; a = 0; b = 1.5; m = 0;
* E; [  _5 f6 R5 S- l+ Kg1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
   DisplayFunction -> Identity];
. H) r& X  B& @( @For[j = 3, j <= 50, j += 2, m = j; tt1 = {}; tt2 = {};
For[i = 0, i < m, i++, x1 = a + i*(b - a)/m; x2 = x1 + (b - a)/m;
  tt1 = Append[tt1,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
8 n6 N' ~" {3 ]( m3 Z" T% d  tt2 = Append[tt2,
. s" Z# A& R1 n7 l    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
  PlotLabel -> m'' intervals'']]
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定积分的动画演示，运行没有结果，请各位大虾看看错在哪里？
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& O4 Z7 s: N2 C/ G( Z4 jf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red,
. _* c! r- e; ^, ]; h4 [  DisplayFunction -> Identity]
For[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
5 N7 Q" h, Z& I) K  t1 = Append[t1,
+ O+ P6 a# {9 u    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[t1, t2, g, DisplayFunction -> $DisplayFunction,
  PlotLabel -> n "intervals"]]

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变动的永恒

太高端，不懂，帮顶
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402

已经解决。谢谢小木虫的大虾。
, L1 t5 z! J3 b! Z" e' X' q( qf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red];
6 T  J, M& k0 I+ k8 zAnimate[t1 = {}; t2 = {};
- i/ a% w- s0 k1 O0 x For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
2 x7 f6 ^$ I: R8 Z  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
0 J5 x. V3 C8 k1 O! Z- i Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
AnimationRunning -> False]

宏心

牛。牛牛。
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z43742516

收藏起来慢慢看
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z43742516

收藏起来慢慢看
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meiya

好牛，厉害
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