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The SparseQR is set as default method. However, in accordance with the previous commit, only if a new enough Eigen library is present will SparseQR be executed.
If the library is old and SparseQR can not be reliably used, FC will automatically fall back to use DenseQR.
This ensures that users that have a new enough library > 3.2.2 will benefit from the performance increase, while the users that use older library will still have
the same performance as in legacy FC.
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A new parameter added to the form in order to control how low a value should be
to be considered zero (how high a value shall be to be accounted for in rank calculation)
Debug for QR pivot threshold is also added.
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- Increased solver debug
- Changing default values from float to string, as float has "only" a precision of 12 decimals.
- Default values as macros
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The solver has been adapted to use Eigen's SparseQR QR decomposition algorithm. The original
Dense QR implementation is maintained and can be selected using the Advanced Control TaskBox (see below).
The use of SparseQR provides over an order of magnitude improvement in solving time in complex sketches due to
the Sparse nature of the Jacobian matrix of the system of equations.
The solver advanced control is a new TaskBox in the Sketcher that allows to select which algorithms are to be used for
the different solving operations and tweak its parameters. It is not intended to be a user control, but means to debug
solving problems and improve the algorithms and their configuration.
This commit also introduces multithread support for Eigen. Currently it is only limited to products and does not provide
a substantial speed improvement. It is expected to have more multithreaded operations in Eigen in the future.
As a bonus, the TaskBoxes in the Taskbar of the Sketcher remember the last state (collapsed or deployed).
