定积分定义动画演示

402

Clear[f, x, a, b];
# j  k7 a6 l  Y& v* vf[x_]： = x^2; a = 0; b = 1.5; m = 0;
% s8 c/ O0 C, vg1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
   DisplayFunction -> Identity];
! E) C- N+ u6 B0 A. YFor[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;
! l% Q: n! [- |! t$ J  tt1 = Append[tt1,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
! c- [2 O# ^) l$ A8 h  tt2 = Append[tt2,
5 A8 I2 M* G, O8 L* S& r    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
  PlotLabel -> m'' intervals'']]
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* ]+ q7 _# J+ r定积分的动画演示，运行没有结果，请各位大虾看看错在哪里？
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! t: \7 N( b; h/ V$ v* \' d) mf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
9 q6 u9 ?, @* L9 ig = Plot[f[x], {x, a, b}, PlotStyle -> Red,
" `2 C& C* Q+ J7 d4 S, k& U  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;
1 s7 `$ l' W4 n9 P0 H& |  t1 = Append[t1,
( L( f% P& v/ c" N4 j* R    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
& p( u- d8 L( ? 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。
$ Q, ?! G1 [( R/ ?3 [0 P2 Lf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red];
+ x0 a; {& J9 RAnimate[t1 = {}; t2 = {};
" S6 N& M, z0 D0 N8 M- A' X; r For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
% f8 U, m+ x5 {% q. b1 t  h; _( U  t1 = Append[t1,
/ J/ g; h; e2 ?2 A! s    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
4 s: `" s, X- w, Q& ?  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
4 O3 |2 t' q( r) v% C( \; P Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
AnimationRunning -> False]
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宏心

牛。牛牛。

z43742516

收藏起来慢慢看

z43742516

收藏起来慢慢看

meiya

好牛，厉害