ji.ds.NROW: Returns the number of rows present in x
In datashield/ji.dev.cl: ji.dev.cl

Description Usage Arguments Value Author(s) Examples

this function is similar to R function NROW with the addition that it also generates a global number of rows (i.e.total number of entries across several datasets)

1 2	ji.ds.NROW(datasources = NULL, x = NULL, type = "combine")

`datasources`	a list of opal object(s) obtained after login in to opal servers; these objects hold also the data assign to R, as `dataframe`, from opal datasources.
`x`	a vector, array, matrix or data frame
`type`	a character which represents the type of analysis to carry out. If `type` is set to 'combine', a global number of rows is calculated if `type` is set to 'split', the number of rows is calculated separately for each study.

an interger of length 1 or NULL

Gaye, A. (amadou.gaye

{

# load that contains the login details
data(logindata)

# login and assign specific variable(s)
opals <- datashield.login(logins=logindata,assign=TRUE)

# Example 1: Get the total number of observations across all the studies
ji.ds.NROW(datasources=opals, x=quote(D))

# Example 2: Get the number of observations on each study
ji.ds.NROW(datasources=opals, x=quote(D), type="split")

# Example 3: Get the total number of observations for the variable 'LAB_TSC' (should be the same as in Example 1)
ji.ds.NROW(datasources=opals, x=quote(D$LAB_TSC))

}