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 = {};
9 T; c  G' ]6 L6 h9 K+ u! n5 v: @ 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]}]}]];
  w. f1 v- R0 ]7 B5 k  tt2 = Append[tt2,
7 y, h0 ]0 P" H1 D. }1 f1 i    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？
( e5 }% R9 `! j% }
( ^7 ^* A; t: m* a0 L* [9 R; ^f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red,
0 E: }  u! U  q" p2 Q9 @  DisplayFunction -> Identity]
/ O) e3 ?7 X, Z1 h4 q; cFor[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
/ ^( ^* X& [- X* P, A 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]}]}]];
% B2 P7 L4 w: v7 r- ~8 O+ L9 ~7 E  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[t1, t2, g, DisplayFunction -> $DisplayFunction,
  PlotLabel -> n "intervals"]]

变动的永恒

太高端，不懂，帮顶
' V- [" r+ u' L' i

402

已经解决。谢谢小木虫的大虾。
f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
- q8 k# z0 X8 h/ P! S2 Vg = Plot[f[x], {x, a, b}, PlotStyle -> Red];
7 _( V4 ], y/ r, \) Z7 C) m' aAnimate[t1 = {}; t2 = {};
For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
  t1 = Append[t1,
8 Y+ p/ m. L% ~0 V    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
2 n! O6 s" f" G4 z4 A  O# e  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
; R. {* A5 v4 S8 y- L Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
) V7 S- T7 O+ `9 N7 @ AnimationRunning -> False]
8 v# J; j9 l8 T0 m. n

宏心

牛。牛牛。

z43742516

收藏起来慢慢看

z43742516

收藏起来慢慢看
: M& a+ m+ P# q5 z

meiya

好牛，厉害