Thank you @Carl Love 

thank you @tomleslie , yep she works well.

can you share me any books of Maple?

@Carl Love thank you

I have modified W as Vector that consist of 1 to n element (not input like previous eqs). W=[W1...Wn] is auto generated by program,the finally equaction is

I use the same code but got error

do you have any methods to calculate W directly? and get the solution as below(for general)

Q4.mw

@Carl Love hi sir

In fact your code is correct but the solution I can't extract and evaluate as numerical.

please guide me

Thank you

Linearly_Solution.mw

@Carl Love thank you it's work well

hello @Carl Love , your code so amazing

back to Flatten: I want to flatten as picture below

I try to flatten but got unwant results,please guide me

----------------------------------Code----------------------------------------

DOe := Matrix(3, 2, [[Vector[column](1, [Vector[row](2, [1, 2])]), Vector[column](1, [Vector[row](2, [3, 4])])], [Vector[column](1, [Vector[row](2, [3, 4])]), Vector[column](1, [Vector[row](2, [5, 6])])], [Vector[column](1, [Vector[row](2, [5, 6])]), Vector[column](1, [Vector[row](2, [1, 2])])]]);

with(ListTools);

with(LinearAlgebra);
with(linalg);

DOF := <K || (1 .. 3)>;

@acer 

yes that is a question. eqs is generated by by another equaction, the question is how to convert from matrix to vector as Tome's sheet without user's input? please guide me

@acer

when I past in tomleslie 12417 's  got errors as well

@acer I removed now but now working. any mistacks ?

@tomleslie I still get error