Putting a vector into part of a row of a matrix
So from the link given here- https://ask.sagemath.org/question/836...
From the answer given, I see that to replace a row (say row 1) on a matrix by a list say List 1, I just do
K[1, :] = vector(List1)
For example,
K = Matrix(QQ, 6, 8)
A priori, this is just the 0 matrix. Now writing
K[1, :] = vector([1, 1, 1, 1, 1, 1, 1, 1])
will replace my first row of my 6 x 8 matrix with the entries all 1's.
However, what if I want to replace say row 1 but only the last 6 entries
so I will have [0, 0, 1, 1, 1, 1, 1, 1]. Of course, I can just type out
K[1, :] = vector([0, 0, 1, 1, 1, 1, 1, 1])
but this is not viable for larger matrices.
An example would be say my K = Matrix(QQ, 40, 80) and I have a list given by L1 = [1, 1, 1, 1].
Suppose I want to replace the row 1 with 40th-43rd entry being L1.
Method 1- Type out 76 zeros and do K[1, :] = vector(L1 with 76 zeros). This is not really ideal.
Method 2- Replace entry by entry. This is also not ideal if my L1 is say of length 20.
Is there a way to just say something like K[1, 40-43] = vector([L1])?
