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我创建了一个阻尼摆相平面的 gif。为此，我使用包 DifferentialEquations.jl 进行集成，使用包 Plots.jl 和 pyplot 后端，使用 ImageMagick.jl 进行绘图和动画。为此，我为不同的初始值集成了函数，并且将它们中的每一个集成了很多次，因此我得到了一些小片段，它们共同以 gif 的形式形成最终图。代码如下：

using DifferentialEquations
using Plots ; default(size=(1000,700))
pyplot()
using ImageMagick

x = linspace(0.0,50.0,101)
tfinal = collect(x)
b = 0.2
p = plot()
u0vals = ([pi,-2.41],[2.0*pi,-2.41],[-2.0*pi,-3.0],[-2pi,3.0])
anim = @animate for j=1:endof(tfinal)
  for i=1:endof(u0vals)
      f = function(t,u,du)
        du[1] = u[2]
        du[2] = -b*u[2] -sin(u[1])
      end
      u0 = u0vals[i]
      tspan=(0.0,tfinal[j])
      prob = ODEProblem(f, u0, tspan)
      sol = solve(prob)
      plot!(p, sol, vars=(1,2),arrow=true,legend = false, titlefont=font(15, "cursive"),title = "STRO Figure 6.7.7", linewidth=1,linecolor=:"black",xlims=(-15.0,10.0),border=false,ticks=nothing,grid=false)
  end
end
gif(anim, "STRO_6_7_7_GIF_.gif",fps=5)

这段代码在我第一次运行时运行良好。但是，我尝试再次运行它来更改它tfinal，它显示了这一点：（signal (11): Segmentation fault: 11这只是来自 julia 的消息的第一行）。然后我尝试再次运行初始代码并收到相同的消息。重新启动 julia 和计算机后，我收到相同的消息。我再次更改了tfinal它并且它再次工作并且对于tfinal我想要使用的每一个。我有我想要的输出。然而，让我感到困扰的是 julia 对我的代码的“反应”是不一致的。如果需要，我可以粘贴完整的错误，但很长。

编辑：这是完整的错误信息

signal (11): Segmentation fault: 11
while loading no file, in expression starting on line 0
ode_interpolation at /Users/pacagal/.julia/v0.5/OrdinaryDiffEq/src/dense/generic_dense.jl:134
[inlined]
InterpolationData at /Users/pacagal/.julia/v0.5/OrdinaryDiffEq/src/interp_func.jl:20
unknown function (ip: 0x32b584519)
macro expansion at /Users/pacagal/.julia/v0.5/DiffEqBase/src/solutions/solution_interface.jl:72 [inlined]
apply_recipe at /Users/pacagal/.julia/v0.5/RecipesBase/src/RecipesBase.jl:238
unknown function (ip: 0x32b5808c6)
jl_call_method_internal at /Users/osx/buildbot/slave/package_osx10_9 x64/build/src/./julia_internal.h:189 [inlined]
jl_apply_generic at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/gf.c:1942
jl_apply at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/./julia.h:1392 [inlined]
jl_f__apply at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/builtins.c:547
_process_userrecipes at /Users/pacagal/.julia/v0.5/Plots/src/pipeline.jl:73
_plot! at /Users/pacagal/.julia/v0.5/Plots/src/plot.jl:171
unknown function (ip: 0x32b57bbed)
jl_call_method_internal at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/./julia_internal.h:189 [inlined]
jl_apply_generic at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/gf.c:1942
#plot!#266 at /Users/pacagal/.julia/v0.5/Plots/src/plot.jl:151
jl_call_method_internal at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/./julia_internal.h:189 [inlined]
jl_apply_generic at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/gf.c:1942
jl_apply at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/./julia.h:1392 [inlined]
jl_f__apply at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/builtins.c:547
#plot! at ./<missing>:0
jl_call_method_internal at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/./julia_internal.h:189 [inlined]
jl_apply_generic at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/gf.c:1942
macro expansion; at ./REPL[10]:11 [inlined]
macro expansion; at /Users/pacagal/.julia/v0.5/Plots/src/animation.jl:154 [inlined]
anonymous at ./<missing> (unknown line)
unknown function (ip: 0x32b5566ff)
jl_call_method_internal at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/./julia_internal.h:189 [inlined]
jl_toplevel_eval_flex at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/toplevel.c:569
jl_toplevel_eval_in_warn at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/builtins.c:590
eval at ./boot.jl:234
jlcall_eval_19752 at /Applications/Julia-0.5.app/Contents/Resources/julia/lib/julia/sys.dylib (unknown line)
jl_call_method_internal at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/./julia_internal.h:189 [inlined]
jl_apply_generic at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/gf.c:1942
eval_user_input at ./REPL.jl:64
unknown function (ip: 0x3192d9e66)
jl_call_method_internal at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/./julia_internal.h:189 [inlined]
jl_apply_generic at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/gf.c:1942
macro expansion at ./REPL.jl:95 [inlined]
#3 at ./event.jl:68
unknown function (ip: 0x3192d30df)
jl_call_method_internal at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/./julia_internal.h:189 [inlined]
jl_apply_generic at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/gf.c:1942
jl_apply at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/./julia.h:1392 [inlined]
start_task at /Users/osx/buildbot/slave/package_osx10_9-x64/build/src/task.c:253
Allocations: 40525029 (Pool: 40521241; Big: 3788); GC: 71

[Proceso completado]
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1 回答 1

1

分段错误是因为您的时间跨度微不足道。

x = linspace(0.0,50.0,101)
tfinal = collect(x)

请注意tfinal[1]=0.0，所以第一个时间跨度是(0.0,0.0)。它所做的是给出一个简单的 diffeq 解决方案，然后尝试绘制它，最终出现边界错误，但边界检查被关闭。哎哟。我提交了一个提交，这样下一个补丁就会抛出一个错误，提醒用户时间跨度是微不足道的。

这意味着解决这个问题的方法是删除第一个时间点：

x = linspace(0.0,50.0,101)
tfinal = collect(x)[2:end]

这会很好。

您可能还想查看提供的动画界面。不确定它是否可以轻松地按照您想要的顺序为所有内容设置动画：这可能需要更多 Plots.jl 控件。

于 2017-03-07T19:53:13.023 回答