Logging
Controlling printing
The following settings are used to control what is printed during
initialization and event generations.
flag Print:init
(default = on)
If disabled, messages (except for errors) are suppressed during
initialization. In order to show only certain types of information, use the
Init:showProcesses,
Init:showMultipartonInteractions,
Init:showChangedSettings,
Init:showAllSettings,
Init:showChangedParticleData,
Init:showChangedResonanceData,
Init:showAllParticleData, and
Init:showOneParticleData settings.
flag Print:next
(default = on)
If disabled, messages (except for errors) are suppressed during event
generation. In order show only certain types of information, use the
Next:numberCount,
Next:numberShowLHA,
Next:numberShowInfo,
Next:numberShowProcess, and
Next:numberShowEvent settings.
flag Print:quiet
(default = off)
Can be set on to avoid the printing during program execution, to the
largest extent possible. This is equivalent to turning off the three flags
above.
Error messages
Error messages are printed through the Logger class. There are five types
of error messages:
- Abort: An abort message indicates a critical error that might
prevent further event generation from taking place. Examples: unable to
find particle database; invalid user settings;
calling
Pythia::next after initialization failed.
- Error: An error indicates that something has gone wrong during event
generation. When an error occurs in a function, it usually means that
function failed to execute. It is possible that the calling function is
able to recover, otherwise the event will fail to generate.
- Warning: Warning messages indicate an exceptional case that the function
is able to recover from. They are usually not a cause for concern, but a
large number of warnings could indicate that there is something wrong with
your configuration.
- Info: Info messages provide information that is not an error. Example:
when the parallel framework automatically detects the number of hardware
threads, this number is output as an Info message.
- Report: Report messages are used to provide additional details that may
be relevant for debugging purposes. These messages are off by default.
In the Logger class, the abortMsg,
errorMsg, warningMsg, and infoMsg
methods are used to generate messages of the corresponding types. However,
the standard way to output error messages is through the
ABORT_MSG, ERROR_MSG, WARNING_MSG,
and INFO_MSG macros. These macros expand to the corresponding
methods, but automatically replaces the first argument by
__METHOD_NAME__. For example, the two lines are equivalent:
infoPtr->ERROR_MSG("an error occurred");infoPtr->errorMsg(__METHOD_NAME__, "an error occurred");
The reason macros are used this way is that there is no other easy way to
automatically propagate the name of the method where the error occurred.
The following settings are used to control error logging features.
flag Print:errors
(default = on)
If on, error messages are printed to the console the first time each
of them occurs. Even if off, errors are still logged and displayed when
calling Pythia::stat.
mode Print:verbosity
(default = 2; minimum = 0; maximum = 3)
This setting determines which types of diagnostic messages are logged.
Messages that don't satisfy the verbosity level will not be printed
when calling Pythia::stat.
option 0 : No error messages are logged.
option 1 : Only critical abort messages are logged.
option 2 : All normal messages are logged (default).
option 3 : Also report messages are logged.
flag Print:useErrorStream
(default = off)
By default, all logger messages are written to cout. If this
flag is turned on, error messages will instead be written
to cerr.