定积分定义动画演示

402

Clear[f, x, a, b];
  ^+ c2 q) i* ]- F; x! ef[x_]： = x^2; a = 0; b = 1.5; m = 0;
g1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
! Y7 \3 V* G. @; l& ]5 `# w   DisplayFunction -> Identity];
For[j = 3, j <= 50, j += 2, m = j; tt1 = {}; tt2 = {};
3 f' A( O( ]* G" L7 g 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]}]}]];
9 r+ A1 F$ b# }7 i/ {2 J; @  tt2 = Append[tt2,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
+ i% h( b& H9 }0 B  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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# I" r) l. r! Z% e2 B: D+ C8 t* vf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
7 G: E  i; G9 n3 Z" Ng = Plot[f[x], {x, a, b}, PlotStyle -> Red,
  DisplayFunction -> Identity]
For[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
" r4 g. |. e6 o" F7 _  S For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
  t1 = Append[t1,
1 y0 C0 Q  K9 ?3 W* y; @    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,
5 A& g! H( p! s( @7 R: l  PlotLabel -> n "intervals"]]
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& W/ _  R4 v& Z! t9 T

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。
# a' r# ^. i- B5 m/ H( ~) Mf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red];
Animate[t1 = {}; t2 = {};
- J! t6 w9 e$ O1 q) \6 g1 } For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
  t1 = Append[t1,
1 U* s" W2 [; x9 C( b    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
5 V. K$ c5 k. h/ Y" K; b6 \ Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
AnimationRunning -> False]

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
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