Adds a single time series variable to a specified group within a JD+ workspace..
Value
No return value (NULL returned invisibly). This function is used for its side effect of modifying the workspace.
Details
For the time being, if the group does not already exist, a new group is created, but the group will be named after name, not group.
Limitations
- Cannot add multiple variables at once. 
- Does not support dynamic ts objects with metadata. 
- If group does not exist, a new group is created but named after the variable name, not the intended group. 
See also
modelling_context to create multiple variables and groups at once,
and read_variables, write_variables to import/export variables.
Examples
# Load a Workspace
file <- system.file("workspaces", "workspace_test.xml", package = "rjd3workspace")
jws <- jws_open(file)
add_variables(jws = jws, group = "reg1", y = AirPassengers, name = "x1")