lusolve

sparse linear system solver

Calling Sequence

lusolve(hand,b)
lusolve(A,b)

Arguments

:b full real matrix : :A real square sparse invertible matrix : :hand handle to a previously computed sparse lu factors (output of

lufact)

:

Description

x=lusolve(hand,b) solves the sparse linear system A*x = b.

[hand,rk]=lufact(A) is the output of lufact.

x=lusolve(A,b) solves the sparse linear system A*x = b

Examples

non_zeros=[1,2,3,4];rows_cols=[1,1;2,2;3,3;4,4];
sp=`sparse`_(rows_cols,non_zeros);
[h,rk]=`lufact`_(sp);x=lusolve(h,[1;1;1;1]);`ludel`_(h)
rk,sp*x

non_zeros=[1,2,3,4];rows_cols=[1,1;2,2;3,3;4,4];
sp=`sparse`_(rows_cols,non_zeros);
x=lusolve(sp,-`ones`_(4,1));
sp*x

See Also

• sparse sparse matrix definition
• lufact sparse lu factorization
• slash (/) right division and feed back
• backslash () left matrix division.