定积分定义动画演示

402

Clear[f, x, a, b];
f[x_]： = x^2; a = 0; b = 1.5; m = 0;
g1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
   DisplayFunction -> Identity];
For[j = 3, j <= 50, j += 2, m = j; tt1 = {}; tt2 = {};
- F: D+ y( o4 [3 w+ ~ For[i = 0, i < m, i++, x1 = a + i*(b - a)/m; x2 = x1 + (b - a)/m;
$ A: ^* k- H1 e! ~8 t  tt1 = Append[tt1,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
% M, Y. u: {' L/ \  tt2 = Append[tt2,
3 `) \3 ]3 F4 y2 e    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
: z, O& M. M2 O5 N Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
: r  M% x, _& n( q( E' F7 w1 b7 g  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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f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
( S: h/ t' h- [. yg = Plot[f[x], {x, a, b}, PlotStyle -> Red,
# |9 A9 @% Q5 h0 }7 K  DisplayFunction -> Identity]
For[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
4 d4 i) f- V) ~* J For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
7 K' z* y) F+ I  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
/ m, `+ j; D3 o: d) K% [ 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。
f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red];
- k2 ?5 m5 v/ x9 s: E6 QAnimate[t1 = {}; t2 = {};
For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
; Q; o, X$ d% R. d; Y. W: z  t1 = Append[t1,
% I) {" z4 V% N- f# r7 v0 \  J    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
+ \/ n0 w) c/ s) ~  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
3 o3 ^8 K: j/ l' G, k1 X Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
% n+ z8 m3 w% O7 f7 E3 p AnimationRunning -> False]
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宏心

牛。牛牛。
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z43742516

收藏起来慢慢看

z43742516

收藏起来慢慢看

meiya

好牛，厉害