我正在閱讀如何使用MATLAB來求解線性方程組。使用MATLAB進行數值分析
在本章中,我們處理幾個數值方法求解方程系統
a11x1 + a12x2 + ·· ·+a1NxN = b1
a21x1 + a22x2 + ·· ·+a2NxN = b2
. . . . . . . . . = .
aM1x1 + aM2x2 + ·· ·+aMNxN = bM
其可以以緊湊的形式通過使用矩陣矢量符號被寫爲
A X = b
mxn
其中:
a11 a12 · · a1N
AM×N = a21 a22 · · a2N
· · · · ·
M1 aM2 · · aMN
x1
x= x2
·
xN
b1
b = b2
·
bM
In which we have 3 cases : M=N;M<N;M>N
我無法理解下面的塊:
The Nonsingular Case (M = N)
x = A^−1 b
so long as the matrix A is not singular
>>A = [1 2;2 4]; b = [-1;-1];
>>x = A^-1*b
Warning: Matrix is singular to working precision.
x = -Inf
-Inf
This is the case where some or all of the rows of the coefficient matrix A are
dependent on other rows and so the rank of A is deficient, which implies that
there are some equations equivalent to or inconsistent with other equations. If
we remove the dependent rows until all the (remaining) rows are independent of
each other so that A has full rank (equal to M), it leads to the case of M <N,
which will be dealt with in the next section.
'A排名不足'的含義是什麼?
感謝您的參考和詳細信息。 – Prakash