Compiling Phrot

[nuggetprime]

Stop-on-prp files now available. Just add the -s switch and it will stop on the first prp.

--nuggetprime

[mdettweiler]

Originally Posted by nuggetprime

I've managed to compile phrot myself on my quad and it seems to don't produce the reported errors.My version is also ~28 percent faster than Geoff's port.

--nuggetprime

Nice! I'll have to try timing it myself sometime soon.

[rogue]

Originally Posted by nuggetprime

Stop-on-prp files now available. Just add the -s switch and it will stop on the first prp.

--nuggetprime

Can you send me the change that you made? I'll make sure that I include it in the version I have.

What I really would like to do next in phrot is to save checkpoint information so that tests can be stopped and re-started. I haven't had the time to work on it, but if someone else wants to attempt that, they are free to do so.

[Cruelty]

Originally Posted by nuggetprime

I've managed to compile phrot myself on my quad and it seems to don't produce the reported errors.My version is also ~28 percent faster than Geoff's port.

From what I see there are only Linux versions... or am I missing something?

[rogue]

I have finally added checkpointing to phrot and support for -s (stopOnPRP). Checkpointing means that phrot will write the current data to disk when during a test. When restarting, phrot will then restart from where it last checkpointed. This will be very helpful when running long tests and you need to shutdown or restart your computer and don't want to have to start a test from the beginning.

I have attached the sources for phrot 0.52. If anyone runs into any issues, please let me know.

[kar_bon]

can anyone compile this version on WIN-platform and attach the exe here? thanks

[rogue]

Originally Posted by kar_bon

can anyone compile this version on WIN-platform and attach the exe here? thanks

You can d/l a P3 build with CygWin from here. This build is also tuned for Core 2 Duo

[MyDogBuster]

Checkpointing means that phrot will write the current data to disk when during a test. When restarting, phrot will then restart from where it last checkpointed. This will be very helpful when running long tests and you need to shutdown or restart your computer and don't want to have to start a test from the beginning.

Does this include not having to worry about the residuals file? I've messed that up more than once, forgetting to save the contents before restarting.

[rogue]

Originally Posted by MyDogBuster

Does this include not having to worry about the residuals file? I've messed that up more than once, forgetting to save the contents before restarting.

What do you mean?

[mdettweiler]

Originally Posted by MyDogBuster

Does this include not having to worry about the residuals file? I've messed that up more than once, forgetting to save the contents before restarting.

Actually, for a while there's been an option to have Phrot output the results to results.out, no fancy output redirection stuff necessary. Simply run "phrot -b=3 -o" to have it produce LLR residuals and output it all to the file results.out.

Another option is to redirect the output to a file as before, but use ">>" instead of ">"--i.e., append to the output file instead of overwriting it.

[rogue]

Originally Posted by mdettweiler

Actually, for a while there's been an option to have Phrot output the results to results.out, no fancy output redirection stuff necessary. Simply run "phrot -b=3 -o" to have it produce LLR residuals and output it all to the file results.out.

Another option is to redirect the output to a file as before, but use ">>" instead of ">"--i.e., append to the output file instead of overwriting it.

Definitely use -o if saving the residuals.

The -s option is also useful for the Conjectures 'R Us project. Here is how you can do it.

1. Take the sieve output file containing multiple k's
2. Use srfile to save each k to its own file
3. Write a shell script (or .bat file) with the following contents:
   • phrot.p3 -b3 -o -s k12345.in
   • rm phrot.ini
   • phrot.p3 -b3 -o -s k56789.in
   • rm phrot.ini
   • etc.
4. Run the script

phrot will stop testing each file when the first prime is found or when it finishes processing the file, whichever comes first. All primes will be in Phrot.prp. All residuals will be in results.out.

I have been thinking about modifying phrot so that if k or b is a power of 2 that it will not perform the test unless using the error checking version. Does anyone have a strong opinion on that?