Package 'ParallelLogger' reference manual

Title:	Support for Parallel Computation, Logging, and Function Automation
Description:	Support for parallel computation with progress bar, and option to stop or proceed on errors. Also provides logging to console and disk, and the logging persists in the parallel threads. Additional functions support function call automation with delayed execution (e.g. for executing functions in parallel).
Authors:	Martijn Schuemie [aut, cre], Marc Suchard [aut], Observational Health Data Science and Informatics [cph]
Maintainer:	Martijn Schuemie <[email protected]>
License:	Apache License 2.0
Version:	3.3.1
Built:	2024-11-03 05:06:30 UTC
Source:	https://github.com/ohdsi/parallellogger

Add the default console logger

Description

Add the default console logger

Usage

addDefaultConsoleLogger(name = "DEFAULT_CONSOLE_LOGGER")
addDefaultConsoleLogger(name = "DEFAULT_CONSOLE_LOGGER")

Arguments

name

A name for the logger.

Details

Creates a logger that writes to the console using the "INFO" threshold and the layoutSimple layout.

Examples

logger <- addDefaultConsoleLogger()
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")
unregisterLogger(logger)
logger <- addDefaultConsoleLogger()
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")
unregisterLogger(logger)

Add the default e-mail logger

Description

Add the default e-mail logger

Usage

addDefaultEmailLogger(
  mailSettings,
  label = Sys.info()["nodename"],
  name = "DEFAULT_EMAIL_LOGGER",
  test = FALSE
)
addDefaultEmailLogger(
  mailSettings,
  label = Sys.info()["nodename"],
  name = "DEFAULT_EMAIL_LOGGER",
  test = FALSE
)

Arguments

`mailSettings`	Arguments to be passed to the `sendmail` function in the `sendmailR` package (except subject and msg).
`label`	A label to be used in the e-mail subject to identify a run. By default the name of the computer is used.
`name`	A name for the logger.
`test`	If TRUE, a message will be displayed on the console instead of sending an e-mail.

Details

Creates a logger that writes to e-mail using the "FATAL" threshold and the layoutEmail layout. This function uses the sendmailR package. Please make sure your e-mail settings are correct by using the sendmailR package before using those settings here. ParallelLogger will not display any messages if something goes wrong when sending the e-mail.

Using GMail

To use a GMail account, make sure to enable 2-step verification on your Google account (see 'Security'). Click on 2-Step Verification, and scroll down to 'App passwords'. Here, you can create an app-specific password to be used with ParallelLogger. You can set host.name = "smtp.gmail.com:587", and be sure to use engine = "curl".

Examples

mailSettings <- list(
  from = "[email protected]",
  to = "[email protected]",
  engine = "curl",
  engineopts  = list(
    username = "[email protected]",
    password = "Secret!"
  ), 
  control = list(
    host.name = "smtp.gmail.com:587"
  )
)

# Setting test to TRUE in this example so we don't really send an e-mail:
addDefaultEmailLogger(mailSettings, "My R session", test = TRUE)
logFatal("Something bad")

unregisterLogger("DEFAULT_EMAIL_LOGGER")
mailSettings <- list(
  from = "[email protected]",
  to = "[email protected]",
  engine = "curl",
  engineopts  = list(
    username = "[email protected]",
    password = "Secret!"
  ), 
  control = list(
    host.name = "smtp.gmail.com:587"
  )
)

# Setting test to TRUE in this example so we don't really send an e-mail:
addDefaultEmailLogger(mailSettings, "My R session", test = TRUE)
logFatal("Something bad")

unregisterLogger("DEFAULT_EMAIL_LOGGER")

Add the default error report logger

Description

Add the default error report logger

Usage

addDefaultErrorReportLogger(
  fileName = file.path(getwd(), "errorReportR.txt"),
  name = "DEFAULT_ERRORREPORT_LOGGER"
)
addDefaultErrorReportLogger(
  fileName = file.path(getwd(), "errorReportR.txt"),
  name = "DEFAULT_ERRORREPORT_LOGGER"
)

Arguments

`fileName`	The name of the file to write to.
`name`	A name for the logger.

Details

Creates a logger that writes to a file using the "FATAL" threshold and the layoutErrorReport layout. The file will be overwritten if it is older than 60 seconds. The user will be notified that the error report has been created, and where to find it.

Add the default file logger

Description

Add the default file logger

Usage

addDefaultFileLogger(fileName, name = "DEFAULT_FILE_LOGGER")
addDefaultFileLogger(fileName, name = "DEFAULT_FILE_LOGGER")

Arguments

`fileName`	The name of the file to write to.
`name`	A name for the logger.

Details

Creates a logger that writes to a file using the "TRACE" threshold and the layoutParallel layout. The output can be viewed with the built-in log viewer that can be started using launchLogViewer.

Remove all registered loggers

Description

Remove all registered loggers

Usage

clearLoggers()
clearLoggers()

Apply a function to a list using the cluster

Description

Apply a function to a list using the cluster

Usage

clusterApply(cluster, x, fun, ..., stopOnError = FALSE, progressBar = TRUE)
clusterApply(cluster, x, fun, ..., stopOnError = FALSE, progressBar = TRUE)

Arguments

`cluster`	The cluster of threads to run the function.
`x`	The list on which the function will be applied.
`fun`	The function to apply. Note that the context in which the function is specifies matters (see details).
`...`	Additional parameters for the function.
`stopOnError`	Stop when one of the threads reports an error? If FALSE, all errors will be reported at the end.
`progressBar`	Show a progress bar?

Details

The function will be executed on each element of x in the threads of the cluster. If there are more elements than threads, the elements will be queued. The progress bar will show the number of elements that have been completed. It can sometimes be important to realize that the context in which a function is created is also transmitted to the worker node. If a function is defined inside another function, and that outer function is called with a large argument, that argument will be transmitted to the worker node each time the function is executed. It can therefore make sense to define the function to be called at the package level rather than inside a function, to save overhead.

Value

A list with the result of the function on each item in x.

Examples

fun <- function(x) {
  return (x^2)
}

cluster <- makeCluster(numberOfThreads = 3)
clusterApply(cluster, 1:10, fun)
stopCluster(cluster)
fun <- function(x) {
  return (x^2)
}

cluster <- makeCluster(numberOfThreads = 3)
clusterApply(cluster, 1:10, fun)
stopCluster(cluster)

Require a package in the cluster

Description

Calls the require function in each node of the cluster.

Usage

clusterRequire(cluster, package)
clusterRequire(cluster, package)

Arguments

`cluster`	The cluster object.
`package`	The name of the package to load in all nodes.

Converts a JSON string to a settings object

Description

Converts a JSON string to a settings object

Usage

convertJsonToSettings(json)
convertJsonToSettings(json)

Arguments

json

A JSON string.

Details

Converts a JSON string generated using the convertSettingsToJson function to a settings object, restoring object classes and attributes.

Value

An R object as specified by the JSON.

Convert a settings object to a JSON string

Description

Convert a settings object to a JSON string

Usage

convertSettingsToJson(object)
convertSettingsToJson(object)

Arguments

object

R object to be converted.

Details

Convert a settings object to a JSON string, using pretty formatting and preserving object classes and attributes.

Value

A JSON string representing the R object.

Create an argument function

Description

Create an argument function

Usage

createArgFunction(
  functionName,
  excludeArgs = c(),
  includeArgs = NULL,
  addArgs = list(),
  rCode = c(),
  newName
)
createArgFunction(
  functionName,
  excludeArgs = c(),
  includeArgs = NULL,
  addArgs = list(),
  rCode = c(),
  newName
)

Arguments

`functionName`	The name of the function for which we want to create an args function.
`excludeArgs`	Exclude these arguments from appearing in the args function.
`includeArgs`	Include these arguments in the args function.
`addArgs`	Add these arguments to the args functions. Defined as a list with format name = default.
`rCode`	A character vector representing the R code where the new function should be appended to.
`newName`	The name of the new function. If not specified, the new name will be automatically derived from the old name.

Details

This function can be used to create a function that has (almost) the same interface as the specified function, and the output of this function will be a list of argument values.

Value

A character vector with the R code including the new function.

Examples

createArgFunction("read.csv", addArgs = list(exposureId = "exposureId"))
createArgFunction("read.csv", addArgs = list(exposureId = "exposureId"))

Create console appender

Description

Create console appender

Usage

createConsoleAppender(layout = layoutSimple)
createConsoleAppender(layout = layoutSimple)

Arguments

layout

The layout to be used by the appender.

Details

Creates an appender that will write to the console.

Examples

appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")                     
appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")

Create e-mail appender

Description

Create e-mail appender

Usage

createEmailAppender(
  layout = layoutEmail,
  mailSettings,
  label = Sys.info()["nodename"],
  test = FALSE
)
createEmailAppender(
  layout = layoutEmail,
  mailSettings,
  label = Sys.info()["nodename"],
  test = FALSE
)

Arguments

`layout`	The layout to be used by the appender.
`mailSettings`	Arguments to be passed to the `sendmail` function in the `sendmailR` package (except subject and msg).
`label`	A label to be used in the e-mail subject to identify a run. By default the name of the computer is used.
`test`	If TRUE, a message will be displayed on the console instead of sending an e-mail.

Details

Creates an appender that will send log events to an e-mail address using the sendmailR package. Please make sure your settings are correct by using the sendmailR package before using those settings here. ParallelLogger will not display any messages if something goes wrong when sending the e-mail.

Using GMail

Examples

mailSettings <- list(
  from = "[email protected]",
  to = "[email protected]",
  engine = "curl",
  engineopts  = list(
    username = "[email protected]",
    password = "Secret!"
  ), 
  control = list(
    host.name = "smtp.gmail.com:587"
  )
)
# Setting test to TRUE in this example so we don't really send an e-mail:
appender <- createEmailAppender(
  layout = layoutEmail,
  mailSettings = mailSettings,
  label = "My R session",
  test = TRUE
)

logger <- createLogger(name = "EMAIL", threshold = "FATAL", appenders = list(appender))
registerLogger(logger)

logFatal("Something bad")

unregisterLogger("EMAIL")
mailSettings <- list(
  from = "[email protected]",
  to = "[email protected]",
  engine = "curl",
  engineopts  = list(
    username = "[email protected]",
    password = "Secret!"
  ), 
  control = list(
    host.name = "smtp.gmail.com:587"
  )
)
# Setting test to TRUE in this example so we don't really send an e-mail:
appender <- createEmailAppender(
  layout = layoutEmail,
  mailSettings = mailSettings,
  label = "My R session",
  test = TRUE
)

logger <- createLogger(name = "EMAIL", threshold = "FATAL", appenders = list(appender))
registerLogger(logger)

logFatal("Something bad")

unregisterLogger("EMAIL")

Create file appender

Description

Create file appender

Usage

createFileAppender(
  layout = layoutParallel,
  fileName,
  overwrite = FALSE,
  expirationTime = 60
)
createFileAppender(
  layout = layoutParallel,
  fileName,
  overwrite = FALSE,
  expirationTime = 60
)

Arguments

`layout`	The layout to be used by the appender.
`fileName`	The name of the file to write to.
`overwrite`	Overwrite the file if it is older than the expiration time?
`expirationTime`	Expiration time in seconds

Details

Creates an appender that will write to a file.

Create a logger

Description

Create a logger

Usage

createLogger(
  name = "SIMPLE",
  threshold = "INFO",
  appenders = list(createConsoleAppender())
)
createLogger(
  name = "SIMPLE",
  threshold = "INFO",
  appenders = list(createConsoleAppender())
)

Arguments

`name`	A name for the logger.
`threshold`	The threshold to be used for reporting.
`appenders`	A list of one or more appenders as created for example using the `createConsoleAppender` or `createFileAppender` function.

Details

Creates a logger that will log messages to its appenders. The logger will only log messages at a level equal to or higher than its threshold. For example, if the threshold is "INFO" then messages marked "INFO" will be logged, but messages marked "TRACE" will not. The order of levels is "TRACE", "DEBUG", "INFO", "WARN", "ERROR, "and FATAL".

Value

An object of type Logger, to be used with the registerLogger function.

Examples

appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")                     
appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")

Exclude variables from a list of objects of the same type

Description

Exclude variables from a list of objects of the same type

Usage

excludeFromList(x, exclude)
excludeFromList(x, exclude)

Arguments

`x`	A list of objects of the same type.
`exclude`	A character vector of names of variables to exclude.

Get all registered loggers

Description

Get all registered loggers

Usage

getLoggers()
getLoggers()

Value

Returns all registered loggers.

Launch the log viewer Shiny app

Description

Launch the log viewer Shiny app

Usage

launchLogViewer(logFileName)
launchLogViewer(logFileName)

Arguments

logFileName

Name of the log file to view.

Details

Launches a Shiny app that allows the user to view a log file created using the default file logger. Use addDefaultFileLogger to start the default file logger.

Examples

# Create a log file:
logFile <- file.path(tempdir(), "log.txt")
addDefaultFileLogger(logFile)
logInfo("Hello world")

# Launch the log file viewer (only if in interactive mode):
if (interactive()) {
  launchLogViewer(logFile)
}

# Delete the log file:
unlink(logFile)
# Create a log file:
logFile <- file.path(tempdir(), "log.txt")
addDefaultFileLogger(logFile)
logInfo("Hello world")

# Launch the log file viewer (only if in interactive mode):
if (interactive()) {
  launchLogViewer(logFile)
}

# Delete the log file:
unlink(logFile)

Logging layout for e-mail

Description

A layout function to be used with an e-mail appender. This layout creates a short summary e-mail message on the event, including stack trace.

Usage

layoutEmail(level, message)
layoutEmail(level, message)

Arguments

`level`	The level of the message (e.g. "INFO")
`message`	The message to layout.

Logging layout for error report

Description

A layout function to be used with an appender. This layout creates a more elaborate error message, for sharing with the developer. If an error occurs in the main thread a summary of the system info will be included.

Usage

layoutErrorReport(level, message)
layoutErrorReport(level, message)

Arguments

`level`	The level of the message (e.g. "INFO")
`message`	The message to layout.

Logging layout for parallel computing

Description

A layout function to be used with an appender. This layout adds the time, thread, level, package name, and function name to the message.

Usage

layoutParallel(level, message)
layoutParallel(level, message)

Arguments

`level`	The level of the message (e.g. "INFO")
`message`	The message to layout.

Simple logging layout

Description

A layout function to be used with an appender. This layout simply includes the message itself.

Usage

layoutSimple(level, message)
layoutSimple(level, message)

Arguments

`level`	The level of the message (e.g. "INFO")
`message`	The message to layout.

Logging layout with stack trace

Description

A layout function to be used with an appender. This layout adds the stack trace to the message.

Usage

layoutStackTrace(level, message)
layoutStackTrace(level, message)

Arguments

`level`	The level of the message (e.g. "INFO")
`message`	The message to layout.

Logging layout with timestamp

Description

A layout function to be used with an appender. This layout adds the time to the message.

Usage

layoutTimestamp(level, message)
layoutTimestamp(level, message)

Arguments

`level`	The level of the message (e.g. "INFO")
`message`	The message to layout.

Examples

appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")                     
appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")

Load a settings object from a JSON file

Description

Load a settings object from a JSON file

Usage

loadSettingsFromJson(fileName)
loadSettingsFromJson(fileName)

Arguments

fileName

Name of the JSON file to load.

Details

Load a settings object from a JSON file, restoring object classes and attributes.

Value

An R object as specified by the JSON.

Log a message at the DEBUG level

Description

Log a message at the DEBUG level

Usage

logDebug(...)
logDebug(...)

Arguments

...

Zero or more objects which can be coerced to character (and which are pasted together with no separator).

Details

Log a message at the specified level. The message will be sent to all the registered loggers.

Log a message at the ERROR level

Description

Log a message at the ERROR level

Usage

logError(...)
logError(...)

Arguments

...

Zero or more objects which can be coerced to character (and which are pasted together with no separator).

Details

Log a message at the specified level. The message will be sent to all the registered loggers.

Log a message at the FATAL level

Description

Log a message at the FATAL level

Usage

logFatal(...)
logFatal(...)

Arguments

...

Zero or more objects which can be coerced to character (and which are pasted together with no separator).

Details

Log a message at the specified level. The message will be sent to all the registered loggers. This function is be automatically called when an error occurs, and should not be called directly. Use stop() instead.

Log a message at the INFO level

Description

Log a message at the INFO level

Usage

logInfo(...)
logInfo(...)

Arguments

...

Zero or more objects which can be coerced to character (and which are pasted together with no separator).

Details

Log a message at the specified level. The message will be sent to all the registered loggers. This is equivalent to calling R's native message() function.

Examples

appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")                     
appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")

Log a message at the TRACE level

Description

Log a message at the TRACE level

Usage

logTrace(...)
logTrace(...)

Arguments

...

Zero or more objects which can be coerced to character (and which are pasted together with no separator).

Details

Log a message at the specified level. The message will be sent to all the registered loggers.

Examples

appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")                     
appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")

Log a message at the WARN level

Description

Log a message at the WARN level

Usage

logWarn(...)
logWarn(...)

Arguments

...

Zero or more objects which can be coerced to character (and which are pasted together with no separator).

Details

Log a message at the specified level. The message will be sent to all the registered loggers. This function is automatically called when a warning is thrown, and should not be called directly. Use warning() instead.

Create a cluster of nodes for parallel computation

Description

Create a cluster of nodes for parallel computation

Usage

makeCluster(
  numberOfThreads,
  singleThreadToMain = TRUE,
  setAndromedaTempFolder = TRUE
)
makeCluster(
  numberOfThreads,
  singleThreadToMain = TRUE,
  setAndromedaTempFolder = TRUE
)

Arguments

`numberOfThreads`	Number of parallel threads.
`singleThreadToMain`	If `numberOfThreads` is 1, should we fall back to running the process in the main thread?
`setAndromedaTempFolder`	When TRUE, the andromedaTempFolder option will be copied to each thread.

Value

An object representing the cluster.

Examples

fun <- function(x) {
  return (x^2)
}

cluster <- makeCluster(numberOfThreads = 3)
clusterApply(cluster, 1:10, fun)
stopCluster(cluster)
fun <- function(x) {
  return (x^2)
}

cluster <- makeCluster(numberOfThreads = 3)
clusterApply(cluster, 1:10, fun)
stopCluster(cluster)

In a list of object of the same type, find those that match the input

Description

In a list of object of the same type, find those that match the input

Usage

matchInList(x, toMatch)
matchInList(x, toMatch)

Arguments

`x`	A list of objects of the same type.
`toMatch`	The object to match.

Details

Typically, toMatch will contain a subset of the variables that are in the objects in the list. Any object matching all variables in toMatch will be included in the result.

Value

A list of objects that match the toMatch object.

Examples

x <- list(
  a = list(name = "John", age = 25, gender = "M"),
  b = list(name = "Mary", age = 24, gender = "F")
)

matchInList(x, list(name = "Mary"))

# $a
# $a$name
# [1] "John"
#
# $a$age
# [1] 25
#
#
# $b
# $b$name
# [1] "Mary"
#
# $b$age
# [1] 24
x <- list(
  a = list(name = "John", age = 25, gender = "M"),
  b = list(name = "Mary", age = 24, gender = "F")
)

matchInList(x, list(name = "Mary"))

# $a
# $a$name
# [1] "John"
#
# $a$age
# [1] 25
#
#
# $b
# $b$name
# [1] "Mary"
#
# $b$age
# [1] 24

Register a logger

Description

Usage

registerLogger(logger)
registerLogger(logger)

Arguments

logger

An object of type Logger as created using the createLogger function.

Details

Registers a logger as created using the createLogger function to the logging system.

Examples

appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")                     
appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")

Save a settings object as JSON file

Description

Save a settings object as JSON file

Usage

saveSettingsToJson(object, fileName)
saveSettingsToJson(object, fileName)

Arguments

`object`	R object to be saved.
`fileName`	File name where the object should be saved.

Details

Save a setting object as a JSON file, using pretty formatting and preserving object classes and attributes.

Select variables from a list of objects of the same type

Description

Select variables from a list of objects of the same type

Usage

selectFromList(x, select)
selectFromList(x, select)

Arguments

`x`	A list of objects of the same type.
`select`	A character vector of names of variables to select.

Examples


x <- list(
  a = list(name = "John", age = 25, gender = "M"),
  b = list(name = "Mary", age = 24, gender = "F")
)
selectFromList(x, c("name", "age"))

# $a
# $a$name
# [1] "John"
#
# $a$age
# [1] 25
#
#
# $b
# $b$name
# [1] "Mary"
#
# $b$age
# [1] 24
x <- list(
  a = list(name = "John", age = 25, gender = "M"),
  b = list(name = "Mary", age = 24, gender = "F")
)
selectFromList(x, c("name", "age"))

# $a
# $a$name
# [1] "John"
#
# $a$age
# [1] 25
#
#
# $b
# $b$name
# [1] "Mary"
#
# $b$age
# [1] 24

Stop the cluster

Description

Stop the cluster

Usage

stopCluster(cluster)
stopCluster(cluster)

Arguments

cluster

The cluster to stop

Examples

fun <- function(x) {
  return (x^2)
}

cluster <- makeCluster(numberOfThreads = 3)
clusterApply(cluster, 1:10, fun)
stopCluster(cluster)
fun <- function(x) {
  return (x^2)
}

cluster <- makeCluster(numberOfThreads = 3)
clusterApply(cluster, 1:10, fun)
stopCluster(cluster)

Unregister a logger

Description

Unregister a logger

Usage

unregisterLogger(x, silent = FALSE)
unregisterLogger(x, silent = FALSE)

Arguments

`x`	Can either be an integer (e.g. 2 to remove the second logger), the name of the logger, or the logger object itself.
`silent`	If TRUE, no warning will be issued if the logger is not found.

Details

Unregisters a logger from the logging system.

Value

Returns TRUE if the logger was removed.

Examples

appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")                     
appender <- createConsoleAppender(layout = layoutTimestamp)

logger <- createLogger(name = "SIMPLE",
                       threshold = "INFO",
                       appenders = list(appender))
registerLogger(logger)                      
logTrace("This event is below the threshold (INFO)")
logInfo("Hello world")                       
unregisterLogger("SIMPLE")

Package 'ParallelLogger'

Help Index

Add the default console logger

Description

Usage

Arguments

Details

Examples

Add the default e-mail logger

Description

Usage

Arguments

Details

Using GMail

Examples

Add the default error report logger

Description

Usage

Arguments

Details

Add the default file logger

Description

Usage

Arguments

Details

Remove all registered loggers

Description

Usage

Apply a function to a list using the cluster

Description

Usage

Arguments

Details

Value

Examples

Require a package in the cluster

Description

Usage

Arguments

Converts a JSON string to a settings object

Description

Usage

Arguments

Details

Value

Convert a settings object to a JSON string

Description

Usage

Arguments

Details

Value

Create an argument function

Description

Usage

Arguments

Details

Value

Examples

Create console appender

Description

Usage

Arguments

Details

Examples

Create e-mail appender

Description

Usage

Arguments

Details

Using GMail

Examples

Create file appender

Description

Usage

Arguments

Details

Create a logger

Description

Usage

Arguments