Going from structure to matrix
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So I'm trying to dynamically solve a matrix and have it so I can reuse it next loop however solve seems to return a structure that I can't dynamically cast back into a matrix.
The only code I've found to do it dynamically fails for reason "CELL2MAT does not support cell arrays containing cell arrays or objects."
%Matlab solver test
NumberOfMasses = 20;
lamda = sym('lamda',[NumberOfMasses NumberOfMasses]);
test = lamda * eye(NumberOfMasses,NumberOfMasses);
eqn = lamda * eye(NumberOfMasses,NumberOfMasses) == eye(NumberOfMasses,NumberOfMasses)*2;
ans = solve(eqn,lamda);
cell2mat(struct2cell(ans))%needs to be a matrix for next loop
Is there something I'm missing to Dynamically cast "ans" back to a matrix? (Preferably without writing code that dynamically builds strings and runs getfield() on the struct)
采纳的回答
madhan ravi
2019-9-1
4 个投票
Why not use struct2array() ? Note: Don’t Name a variable named ans .
5 个评论
Dion Richardson
2019-9-1
编辑：Dion Richardson
2019-9-1
madhan ravi
2019-9-1
I don’t see any alternatives at the moment, if you get the desired result using reshape() then why not use it, anyhow you’re willing to use it in a loop??
Walter Roberson
2019-9-1
>> anz = solve(eqn,lamda);
>> anz
anz =
struct with fields:
lamda1_1: [1×1 sym]
lamda2_1: [1×1 sym]
lamda3_1: [1×1 sym]
lamda4_1: [1×1 sym]
lamda5_1: [1×1 sym]
lamda6_1: [1×1 sym]
lamda7_1: [1×1 sym]
lamda8_1: [1×1 sym]
lamda9_1: [1×1 sym]
lamda10_1: [1×1 sym]
lamda11_1: [1×1 sym]
lamda12_1: [1×1 sym]
lamda13_1: [1×1 sym]
lamda14_1: [1×1 sym]
lamda15_1: [1×1 sym]
lamda16_1: [1×1 sym]
lamda17_1: [1×1 sym]
lamda18_1: [1×1 sym]
lamda19_1: [1×1 sym]
lamda20_1: [1×1 sym]
lamda1_2: [1×1 sym]
Look at the order of the fields: all of the _1 appear then all of the _2 and so on. Is that the order that you want the matrix to show up as?
I suggest that instead of converting to array, that you use:
subs(lambda, anz)
Dion Richardson
2019-9-1
编辑：Dion Richardson
2019-9-1
madhan ravi
2019-9-1
Thank you sir Walter!
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