Thanks, But now am getting different error.
./plink_1.9_linux_160914 --file 50_samples --make-bed --out 50_samples_try
PLINK v1.90b2i 64-bit (8 Sep 2014) https://www.cog-genomics.org/plink2
(C) 2005-2014 Shaun Purcell, Christopher Chang GNU General Public License v3
Logging to 50_samples_try.log.
15741 MB RAM detected; reserving 7870 MB for main workspace.
Error: Failed to open 50_samples.map.
