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Exercise 1: Effects of an ill-conditioned matrix.

A simple demonstration of the effects of an ill-conditioned matrix on the accuracy of obtaining the inverse of a matrix - and thus the subsequent solution of a system - can be found by considering the following matrix:

Obtain the subroutines dgeco.f, dgedi.f, dgesl.f, and dsvdc.f from the linpack directory of netlib. This can be accomplished by sending email to with the line, send filename.f from linpack, in the text section. Netlib will automatically send the code back to you in an email message.

Note: If you have not used netlib before, you might want to look at the available software and read the section on netlib in the Linear Algebra chapter of CSEPgif.