KB232741: The R function sink() does not write output to a file in MicroStrategy Intelligence Server 9.4.1.

SYMPTOM:
In R, the sink() function writes output to a specified file. When leveraging this function in the Strategy R integration, however, output will not be written.
 
STEPS TO REPRODUCE:

1. Suppose that a user wishes to perform a paired t-test with the two metric values and store the test result to a file.

1. Define an R script as follows and add an appropriate R metric to the above report

# assign the value of Phobia Score 1 and 2 to var1 and var2 respectively
var1 <- c(rMetric1)
var2 <- c(rMetric2)

# perform a paired t-test and write the output to a file
sink("C:/Users/Administrator/Desktop/R/T Test/Output/output.txt", append=FALSE)
t.test(var1, var2, paired=TRUE)
sink()

# assign the value of var1 to a variable, which will be sent back to MSTR
output <- var1

# save as RDATA for further investigation
save.image("C:/Users/Administrator/Desktop/R/T Test/t-test.RData")

1. Before the execution, the output folder is empty

1. After running the report with the R metric, output.txt is generated but the content is empty.

1. Further investigation: after loading “t-test.Rata” and perform the t-test in the same way in the R console, test result is written to output.txt as expected.

 
 
CAUSE:
This is a known issue in Strategy Intelligence Server 9.4.1.
 
ACTION:
Currently this issue is still being reviewed for feasibility by our Technology team and it is not scoped for any upcoming scheduled Strategy release.
 
Third Party Software Installation: WARNING:
The third-party product(s) discussed in this technical note is manufactured by vendors independent of Strategy. Strategy makes no warranty, express, implied or otherwise, regarding this product, including its performance or reliability.