## Define parameters as separate vectors.
X_vector <- 1:4
Y_vector <- c("A", "B", "C")

## In this example there are 12 possible combinations
## and therefore 12 tasks that need to be run.
## Use expand.grid to generate all possible parameter combinations 
param_grid <- expand.grid(X = X_vector, Y = Y_vector)

## expand.grid returns a dataframe.  In this example it returns 12 rows, which
## matches the expected 12 tasks we will need to run.

## Next we need the $SGE_TASK_ID argument from the command line.
## Get the argument that was passed via command line.
argv <- commandArgs(TRUE)
if (length(argv) > 0){
  
  # In this example $SGE_TASK_ID is the first argument
  # located at index of 1 (e.g. argv[1])
  # Save the $SGE_TASK_ID value to 'task_ID' variable
  task_ID <- as.numeric( argv[1] )
}

## Learn more about the $SGE_TASK_ID argument in file "param_sweep.qsub"

## Consider each row of the 'param_grid' dataframe as a task number.
## We then use the 'task_ID' value as a row index to extract 
## the parameters to be used for this task run.

X <- param_grid[task_ID,]$X
Y <- param_grid[task_ID,]$Y


## Run your analysis
print(paste("Task ID:", task_ID))
print(paste("Parameter 1:", X))
print(paste("Parameter 2:", Y))