YoungLu0
YoungLu0
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请问怎么在ParametricPlot3D里调坐标轴范围，我用PlotRange不行 代码如下： Clear[r, s, t, n, b, \[Kappa], \[Tau], r0, t0, n0, b0]; eqns = {t'[s] == \[Kappa][s] n[s], n'[s] == -\[Kappa][s] t[s] + \[Tau][s] b[s], b'[s] == -\[Tau][s] n[s], r'[s] == t[s], t[0] == t0, n[0] == n0, b[0] == b0, r[0] == r0}; \[Kappa][s_] := 10.08 Sin[Pi s]^2; \[Tau][s_] := 3 Cos[Pi s]; {t0, n0, b0} = Orthogonalize[{{1, 0, 0}, {0, 1, 0}, {0, 0, 1}}]; r0 = {0, 0, 0}; sol = First@NDSolve[eqns, {r, t, n, b}, {s, 0, 12}]; With[{s1 = (r /. sol)["Domain"][[1, 1]], s2 = (r /. sol)["Domain"][[1, 2]]}, Manipulate[ Show[ParametricPlot3D[Evaluate[r[s] /. sol], {s, s1, s2}, ImageSize -> 300, BoxRatios -> {1, 1, 1}, PlotStyle -> {Thick, Brown}, PlotRangePadding -> 1], Graphics3D[ Dynamic@ Translate[{Thick, Red, Arrow[{{0, 0, 0}, t[s0]}], Green, Arrow[{{0, 0, 0}, n[s0]}], Blue, Arrow[{{0, 0, 0}, b[s0]}]} /. sol, r[s0] /. sol]]], {s0, s1, s2}]]
用NDSolve解完方程后无法画出曲线，请问该怎么处理？(代码如下) intrinsic[f_, a_ : 0, {c_ : 0, d_ : 0, e_ : 0}, {min : -10, max : 10}, opts_][t_] := Module[{x, y, \[Theta], s}, eqic = {x'[s] == Cos[\[Theta][s]], y'[s] == Sin[\[Theta][s]], \[Theta]'[s] == f[s], x[a] == c, y[a] == c, y[a] == d, \[Theta][a] == e}; sol = NDSolve[eqic, {x, y, \[Theta]}, {s, min, max}, opts]; {x[t], y[t]} /. sol ]; f[s_] := s/(s + 1); \[Alpha][t_] := intrinsic[f, 0, {0, 0, 0}, {0, 20}] ParametricPlot[Evaluate[\[Alpha][t]], {t, 0, 20}]
使用NDSolveValue报错如下，请问该怎么修改？ 这个方程是严格可解的，解出来应该是螺旋线 A = 3; B = 2; c = 1; \[Kappa] = A/c^2; \[Tau] = B/c^2; r[s_] := {x[s], y[s], z[s]}; t[s_] = r'[s]; n[s_] = t'[s]/\[Kappa]; b[s_] = Cross[t[s], n[s]]; NDSolveValue[t'[s] == \[Kappa] n[s], n'[s] == -\[Kappa] t[s] + \[Tau] b[s], b'[s] == -\[Tau] n[s], r[0] == {A, 0, 0}, r'[0] == {0, A/c, B/c}, r''[0] == {-A/c^2, 0, 0}, r'''[0] == {0, -A/c^3, 0}, {x, y, z}, {s, 0, 2 \[Pi]}]
使用ParametricPlot3D，无法画出曲线，请问要怎么调整？ Subscript[r, 1][ l_] = \[Sqrt]2 Sin[\[Pi] l] {0, (Sin^2)[(\[Pi] l)/2], ( Cos^2)[(\[Pi] l)/2]}; Subscript[r, 2][ l_] = \[Sqrt]2 Sin[\[Pi] l] {(Sin^2)[(\[Pi] l)/2], ( Cos^2)[(\[Pi] l)/2], 0}; R[l_] = (1 - l)* Subscript[r, 1][l] + l *Subscript[r, 2][l]; ParametricPlot3D[R[l], {l, 0, 1}]
用NDSolve报错和原代码如下，请问该怎么修改？ Subscript[T, 1] = \[Pi]/2; Subscript[T, 2] = \[Pi]; \[Kappa][t_] = 1; \[Tau][t_] = Piecewise[{{0, 0 <= t < Subscript[T, 1]}, {1000, t = Subscript[T, 1]}, {0, Subscript[T, 1] < t <= Subscript[T, 2]}}]; r[t_] := {x[t], y[t], z[t]}; n[t_] = {x''[t]/\[Kappa][t], y''[t]/\[Kappa][t], z''[t]/\[Kappa][t]}; b[t_] = Cross[r'[t], n[t]]; sol3 = NDSolve[{n'[t_] == -(\[Kappa][t]*r'[t] + \[Tau][t]*b[t]), b'[t] == -\[Tau][t]*n[t], r[0] == 0, r[Subscript[T, 2]] == 0, r'[0] == {0, 0, 1}}, {x, y, z}, {t, 0, \[Pi]}]; ParametricPlot3D[Evaluate[x[t], y[t], z[t]] /. sol3, {t, 0, \[Pi]}]
CK3一进游戏，鼠标拼命往右下角跑，怎么解决？ 退出游戏，鼠标就回复正常了，重装游戏也没有改善
大哥们，xbox的线上模式进不去，该怎么办？
现在沿河劫掠怎么只能携带一个异域物资了？
有大哥知道遗产这个游戏还在更新吗？背景就是男主到一个庄园当男仆
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