定积分定义动画演示

402

Clear[f, x, a, b];
% B9 s0 I* {& d/ ]2 B% Df[x_]： = x^2; a = 0; b = 1.5; m = 0;
- \4 ?8 C7 A2 z' a9 {$ ]1 rg1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
   DisplayFunction -> Identity];
. }5 @( P, }; V- I7 ZFor[j = 3, j <= 50, j += 2, m = j; tt1 = {}; tt2 = {};
# e. F" O0 `$ Z4 V/ _ For[i = 0, i < m, i++, x1 = a + i*(b - a)/m; x2 = x1 + (b - a)/m;
  tt1 = Append[tt1,
0 O; K$ D' b; W: X, f* l$ Z    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
$ r& e5 X, x  L: N  tt2 = Append[tt2,
# b# u/ T9 M7 H/ r& K& |% A    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
4 Y6 Y6 n0 u5 }$ F$ H' U 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？

f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red,
  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;
  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
9 _: t8 s, |# i* ~ 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。
4 K- ~% u! c0 R4 rf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red];
Animate[t1 = {}; t2 = {};
" w0 [* r0 X9 y6 ^0 x1 F For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
; q4 V- W9 x4 H 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

z43742516

收藏起来慢慢看
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meiya

好牛，厉害
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