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Comment Re:Faster than Light? (Score 4, Interesting) 276

Found this on wikipedia:

http://en.wikipedia.org/wiki/Faster-than-light#Faster_light_.28Casimir_vacuum_and_quantum_tunnelling.29

Faster light (Casimir vacuum and quantum tunnelling)

Raymond Y. Chiao was first to measure the quantum tunnelling time, which was found to be between 1.5 to 1.7 times the speed of light.

Einstein's equations of special relativity postulate that the speed of light in a vacuum is invariant in inertial frames. That is, it will be the same from any frame of reference moving at a constant speed. The equations do not specify any particular value for the speed of the light, which is an experimentally determined quantity for a fixed unit of length. Since 1983, the SI unit of length (the meter) has been defined using the speed of light.

The experimental determination has been made in vacuum. However, the vacuum we know is not the only possible vacuum which can exist. The vacuum has energy associated with it, unsurprisingly called the vacuum energy. This vacuum energy can perhaps be changed in certain cases.[38] When vacuum energy is lowered, light itself has been predicted to go faster than the standard value c.

Comment Re:gprof (and anything under the sun.) (Score 1) 254

+1 to parent.

I used ecipse, doxygen, nm, dot to understand code. Understand, control, refactor, repeat is the main method. The details vary from project to project.
If something is too complex to understand try to isolate it. Maybe you will need to replace it later. Modular code is your friend.
Very important: make small changes and commit them often so you can backtrack if you make a misstep. Use your favorite version control tool. I used hg+svn but use whatever you like best. Prefer to commit atomic changes, for example single changes in functionality, so you can undo one thing without breaking another.
I don't use source navigator since more than 10 years but I don't think you'll need it with Eclipse+doxygen.
FIrst add documentation and small changes. I use to add doxygen comments and convert old K&R code to ansi c o c++ first to gain type checking without changing any semantic.

Comment Re:ORACLE = One Raging Asshole Called Larry Elliso (Score 1) 405

There is an ongoing project for development of a python front end for GCC. I don't know its current status but it most be experimental.
Also there is the Java implementation of Python, JPython. By virtue of running over the JVM Just In Time compiler Python code gets compiled to native code in runtime eventually.
I can understand your point about C but the lastest C++ compilers are looking real good for the same job, even if you limit yourself to a subset of C++. I have been converting some old libraries and small apps from C to more modern C++ using mostly strings and maps and I can report that is much safer and readable than C. Just using std::string to replace char*s have been a pleasure in security gained, even if std::string is not very nice.
Practically hadn't needed pointers in most cases.

Comment Re:Why not update your JRE? (Score 1) 405

If your app in java 1.4 uses swings it may hit some bumps in the migration to java 5 to java 6 to java 7. I have a real case of that. Mostly is a case of loose programming for swing in 1.4 that got stricter in later versions.
Surprisingly going directly from 1.4 to 7 seems to work fine. Only god knows why. I can't find anything on the release notes that explains it.

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