Jest: Frequently Asked Questions
(alright, not so frequently asked questions)
The simulated annealing solver might be a good place to start
since it works for very simple operators. I have the feeling there
are better simulated annealing algorithms out there.
Next solver might be the CGSolver that requires a linear operator.
Obviously, we would like to have the additional precision that double
number representation offers.
I plan to change to a double version (I hope a script can simply
translate the future double version to a float version).
However, for seismic imaging
we prefer floats since our data set size already stretches our storage
capabilities (A seismic 3-D data is at least several Gigabytes large).
Since my primary applications concern seismic processing, I implemented
a float version first.
I have the package stored in /home/matt/jest. Consequently, I add
:/home/matt/jest/: to my classpath.
All the import statements then define the
packages relative to that directory,
e.g. /home/matt/jest/jam/vector/Vector.java is found by having a
classpath /home/matt/jest/ and by having an import statement
What is a good solver to start with?
Why float rather than double as the default for real numbers?
How do I set my classpath?
Why not having a single Jest package?
Why does Jest not include an Rn vector and a matrix multiplication operator?
If you need an import statement
import jest.*; or
you do something different from what I do in my setup. I am not sure
Obviously including and searching many packages is ugly and inefficient.
However, Jest currently uses many packages
(jam.vector.*; jam.operator.*; etc).
I will reduce the number of packages for standard classes in the future.
However, controversial or prototype classes I will contain in individual
packages so that they can easily be exchanged, left out, or deinstalled.
I believe this modular approach will make Jest more attractive to more
users. At this early development stage almost all classes are controversial
and prototypes. Consequently, I have many packages. As these packages
mature I will unite them to bigger bins.
Additionally, I believe in reproducible research (for more information
visit my corresponding
In my current design a research project and its document map into
individual Java packages. I will explain this soon somewhere else.
I had matrix multiplication and Rn vectors in an earlier version but
I have not implemented them yet in the current package. Honestly,
Rn does not appear in my research. I usually use a more sophisticated
package Rsf that includes Rn. It adds descriptions of the physical
dimensions to Rn.
Matrix multiplication again is not an operator I encounter in my research
in its pure form. Our linear operators are such sparse matrices, that we
never implement them as explicit matrices.
However, I agree, it would be nice to have these packages. So if you
implement them, store them in an individual package and I will add
it to my distribution. That is easy because of the modularity of
Jest's packages that I discussed above.