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倍频程dsolve SymPy错误:Python异常:AttributeError:';列表';对象没有属性';潜艇';_Python_Octave_Sympy_Symbolic Math_Ode - Fatal编程技术网

倍频程dsolve SymPy错误:Python异常:AttributeError:';列表';对象没有属性';潜艇';

倍频程dsolve SymPy错误:Python异常:AttributeError:';列表';对象没有属性';潜艇';,python,octave,sympy,symbolic-math,ode,Python,Octave,Sympy,Symbolic Math,Ode,(我试着把这篇文章发到这里,但他们说要发到这里;如果这篇文章又离题了,很抱歉。) 我第一次在八度音阶上使用dsolve(非常感谢包括此功能,顺便说一句;此SimPy连接非常好),它可以很好地用于我尝试过的大多数ODE和IVP,但这一次给了我一个错误: >> pkg load symbolic >> syms x(t) >> ode1 = diff(x,t) == -t/x >> cond1 = x(0) == 5 >> dsolve(o

(我试着把这篇文章发到这里,但他们说要发到这里;如果这篇文章又离题了,很抱歉。)

我第一次在八度音阶上使用dsolve(非常感谢包括此功能,顺便说一句;此SimPy连接非常好),它可以很好地用于我尝试过的大多数ODE和IVP,但这一次给了我一个错误:

>> pkg load symbolic
>> syms x(t)
>> ode1 = diff(x,t) == -t/x
>> cond1 = x(0) == 5
>> dsolve(ode1, cond1)
error: Python exception: AttributeError: 'list' object has no attribute 'subs'
    occurred at line 15 of the Python code block error: called from
    python_cmd at line 176 column 5
    dsolve at line 200 column 10
仅仅解决颂歌就行了;它只会在IVP中崩溃:

>> dsolve(ode1)
ans =
{
(sym)

             _________
            ╱       2
  x(t) = -╲╱  C₁ - t

(sym)

            _________
           ╱       2
  x(t) = ╲╱  C₁ - t
我尝试了其他初始条件,但得到了相同的错误:

>> cond2 = x(-3) == 0.1
warning: Using rat() heuristics for double-precision input (is this what you wanted?)
warning: called from
    sym at line 225 column 7
    binop_helper at line 60 column 5
    ineq_helper at line 35 column 5
    eq at line 91 column 5
cond2 = (sym) x(-3) = 1/10
>> dsolve(ode1, cond2)
error: Python exception: AttributeError: 'list' object has no attribute 'subs'
    occurred at line 15 of the Python code block
error: called from
    python_cmd at line 176 column 5
    dsolve at line 200 column 10

有人能帮忙吗?我真的很想用八度音阶来明确地解决ODE和IVP问题。简短的回答是:

不幸的是,它尚未得到支持

较长的答案:

我遇到了同样的问题,并查看了脚本内部,看看哪里出了问题

在dsolve.m函数的第174行,您将发现以下内容:

% FIXME: it is not currently supported a list of boundary/initial conditions
你能做什么:

如果你真的需要它,我建议联系软件包的作者,让他们知道实际上有人想要这个功能。访问Forge页面查看包作者的详细信息

(这是老帖子)