Specifically concerning EISPACK. what happened was that J W (Jim) Wilkinson in the UK (whose career as an applied mathematician started with practical ballistic modelling in WWII, working with Turing and other computing pioneers, and continued for the rest of his life at the UK National Physical Laboratory, not in some academic ivory tower) re-invented the entire foundation of computational linear algebra - or more accurately, gave it a practical foundation for the first time in the history of mathematics, with the new concept of "inverse" or "backward" error analysis.

Wilkinson's 700-page book from the 1960s "The Algebraic Eigenvalue Problem" is still a classic. The IBM SSP borrowed a couple of simple algorithms from it (plus another one invented by Jacobi way back in 1840s!) but EISPACK was "the whole nine yards." The EISPACK library only contained algorithms for eigenvalue problems. It had about 70 different algorithms, compared with four in IBM SSP.

EISPACK was not "written by academics" but created at Argonne National Lab in the USA, with the objective of being portable and free public domain software (And having cut his teeth working on EISPACK and LINPACK as a new graduate, Dongarra then went on to develop the LAPACK library which made both of them obsolete)

As an ironic footnote, Wilkinson was completely dismissive of a class of eigenvalue extraction methods now known as Arnoldi iteration, claiming (rightly) that they were of huge theoretical importance but (wrongly) could never be made to work in practical numerical analysis because of problems with rounding errors. Solutions to the numerical problems were discovered in the 1980s and these algorithms are now the "goto" standard methods for solving eigenproblems that are orders of magnitude bigger than anything Wilkinson could have imagined.

THE IBM SSP was also not competitive with commercial libraries such as IMSL (first released in 1970) which were much more comprenhensive (thousands of routines, not about 100) and not restricted to one computer manufacturer's products.

Specifically concerning EISPACK. what happened was that James Hardy "Jim" Wilkinson in the UK (whose career as an applied mathematician started with practical ballistic modelling in WWII, working with Turing and other computing pioneers, and continued for the rest of his life at the UK National Physical Laboratory, not in some academic ivory tower) re-invented the entire foundation of computational linear algebra - or more accurately, gave it a practical foundation for the first time in the history of mathematics, with the new concept of "inverse" or "backward" error analysis.

Wilkinson's 700-page book from the 1960s "The Algebraic Eigenvalue Problem" is still a classic. The IBM SSP borrowed a couple of simple algorithms from it (plus another one invented by Jacobi way back in 1840s!) but EISPACK was "the whole nine yards." The EISPACK library only contained algorithms for eigenvalue problems. It had about 70 different algorithms, compared with four in IBM SSP.

EISPACK was not "written by academics" but created at Argonne National Lab in the USA, with the objective of being portable and free public domain software (And having cut his teeth working on EISPACK and LINPACK as a new graduate, Dongarra then went on to develop the LAPACK library which made both of them obsolete)

As an ironic footnote, Wilkinson was completely dismissive of a class of eigenvalue extraction methods now known as Arnoldi iteration, claiming (rightly) that they were of huge theoretical importance but (wrongly) could never be made to work in practical numerical analysis because of problems with rounding errors. Solutions to the numerical problems were discovered in the 1980s and these algorithms are now the "goto" standard methods for solving eigenproblems that are orders of magnitude bigger than anything Wilkinson could have imagined.

THE IBM SSP was also not competitive with commercial libraries such as IMSL (first released in 1970) which were much more comprenhensive (thousands of routines, not about 100) and not restricted to one computer manufacturer's products.

Specifically concerning EISPACK. what happened was that J W (Jim) Wilkinson in the UK (whose career as an applied mathematician started with practical ballistic modelling in WWII, working with Turing and other computing pioneers, and continued for the rest of his life at the UK National Physical Laboratory, not in some academic ivory tower) re-invented the entire foundation of computational linear algebra - or more accurately, gave it a practical foundation for the first time in the history of mathematics, with the new concept of "inverse" or "backward" error analysis.

Wilkinson's 700-page book from the 1960s "The Algebraic Eigenvalue Problem" is still a classic. The IBM SSP borrowed a couple of simple algorithms from it (plus another one invented by Jacobi way back in 1840s!) but EISPACK was "the whole nine yards."

EISPACK was not "written by academics" but created at Argonne National Lab in the USA, with the objective of being portable and free public domain software (And having cut his teeth working on EISPACK and LINPACK as a new graduate, Dongarra then went on to develop the LAPACK library which made both of them obsolete)

The EISPACK library only contained algorithms for eigenvalue problems, compared with the IBM SSP which had four routines for eigenvalue extraction out of a total of more than 100.

As an ironic footnote, Wilkinson was completely dismissive of a class of eigenvalue extraction methods now known as Arnoldi iteration, claiming (rightly) that they were of huge theoretical importance but (wrongly) could never be made to work in practical numerical analysis because of problems with rounding errors. Solutions to the numerical problems were discovered in the 1980s and these algorithms are now the "goto" standard methods for solving eigenproblems that are orders of magnitude bigger than anything Wilkinson could have imagined.

THE IBM SSP was also not competitive with commercial libraries such as IMSL (first released in 1970) which were much more comprenhensive (thousands of routines, not about 100) and not restricted to one computer manufacturer's products.

Specifically concerning EISPACK. what happened was that J W (Jim) Wilkinson in the UK (whose career as an applied mathematician started with practical ballistic modelling in WWII, working with Turing and other computing pioneers, and continued for the rest of his life at the UK National Physical Laboratory, not in some academic ivory tower) re-invented the entire foundation of computational linear algebra - or more accurately, gave it a practical foundation for the first time in the history of mathematics, with the new concept of "inverse" or "backward" error analysis.

Wilkinson's 700-page book from the 1960s "The Algebraic Eigenvalue Problem" is still a classic. The IBM SSP borrowed a couple of simple algorithms from it (plus another one invented by Jacobi way back in 1840s!) but EISPACK was "the whole nine yards." The EISPACK library only contained algorithms for eigenvalue problems. It had about 70 different algorithms, compared with four in IBM SSP.

EISPACK was not "written by academics" but created at Argonne National Lab in the USA, with the objective of being portable and free public domain software (And having cut his teeth working on EISPACK and LINPACK as a new graduate, Dongarra then went on to develop the LAPACK library which made both of them obsolete)

As an ironic footnote, Wilkinson was completely dismissive of a class of eigenvalue extraction methods now known as Arnoldi iteration, claiming (rightly) that they were of huge theoretical importance but (wrongly) could never be made to work in practical numerical analysis because of problems with rounding errors. Solutions to the numerical problems were discovered in the 1980s and these algorithms are now the "goto" standard methods for solving eigenproblems that are orders of magnitude bigger than anything Wilkinson could have imagined.

THE IBM SSP was also not competitive with commercial libraries such as IMSL (first released in 1970) which were much more comprenhensive (thousands of routines, not about 100) and not restricted to one computer manufacturer's products.