定积分定义动画演示

402

Clear[f, x, a, b];
1 d: p4 j8 g! l3 w" B/ e4 U  D( s  yf[x_]： = x^2; a = 0; b = 1.5; m = 0;
g1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
4 a8 k, A! R# t) p! M   DisplayFunction -> Identity];
% R( p0 f% m6 f9 l' {6 O; ?( JFor[j = 3, j <= 50, j += 2, m = j; tt1 = {}; tt2 = {};
- Z+ d. K6 w: D For[i = 0, i < m, i++, x1 = a + i*(b - a)/m; x2 = x1 + (b - a)/m;
  tt1 = Append[tt1,
4 \9 ^, r, }% ~  U    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
  tt2 = Append[tt2,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
  PlotLabel -> m'' intervals'']]

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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7 y5 j- e9 w: Y6 j6 W4 gf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red,
  H- d" E* C% J: r3 g  DisplayFunction -> Identity]
For[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
7 r+ R; i6 Q" P  x7 S. S8 T7 j For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
$ H) V9 R: |9 I: Q: W  t1 = Append[t1,
    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,
1 L2 ^' Q4 l% S% ^' N9 T6 Q3 j  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];
Animate[t1 = {}; t2 = {};
# G+ u4 ~# c/ X2 S For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
: _) h2 B, ~. r/ W% k+ w$ U0 r  t1 = Append[t1,
1 h# i9 L6 m$ U  A! B0 X    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
/ F' ?) X) j" @+ P. i" v  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
/ S4 x; a% I% X' M# o 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

meiya

好牛，厉害