jrc (version 0.6.0)

sendData: Send data to a web page

Description

Sends a variable to a web page, where it is saved under a specified name. This function is a wrapper around sendData method of class Session.

Usage

sendData(
  variableName,
  variable,
  keepAsVector = FALSE,
  rowwise = TRUE,
  sessionId = NULL,
  wait = 0
)

Arguments

variableName

Name that the variable will have on the web page.

variable

Variable to send.

keepAsVector

If TRUE, variables with length 1 will be saved as arrays on the web page, otherwise they will be converted to atomic types.

rowwise

If TRUE, matrices and data.frames will be transformed into JavaScript objects or arrays row wise (e.g. a matrix will become an Array of its rows).

sessionId

An ID of the session to which the data should be sent. Can also be a vector of multiple session IDs. If NULL, the data will be sent to all currently active sessions.

wait

If wait > 0, after sending the message, R will wait for a reply for a given number of seconds. For this time (or until the reply is received), execution of other commands will be halted. Any incoming message from the session will be considered as a reply.

Details

To send data back from the web page to the current R session one should usejrc.sendData(variableName, variable, internal). Its arguments are:

variableName

Name that the variable will have in the R session. If variable name hasn't been previously added to the list of allowed variables (see allowVariables or allowedVariables argument of the openPage function), attempt to assign it from a web page will require manual authorization on the R side.

variable

Variable to send.

internal (optional)

Whether this variable should be used only by the session that sent it. If true, variable will be stored in the session-specific environment and can be accessed from the outside with getSessionVariable function. If false, variable will be saved to the outer environment of the app (see setEnvironment). By default, uses true for variables that already exist in the session specific environment (see setSessionVariables or sessionVariables argument of the openPage function.) and false otherwise.

See Also

authorize, allowVariables, sendCommand, callFunction, sendHTML, openPage, getSessionIds.

Examples

if (FALSE) {
# to run this example an installed web browser is required
openPage()
x <- 1:100
sendData("x", x)
sendCommand("console.log(x);")
sendCommand("jrc.sendData('x', x.filter(function(e) {return e % 2 == 0}))")
closePage()}