You can get it here: http://swift.cmbi.ru.nl/gv/dssp/

Go to Distribution in the left panel. Its an executable file. You need to download it and change its permissions (chmod a+x) and then export the path in your bash.rc file.

Yeah Nitika is right. In simpler terms it can be like,

1. Download DSSP executable from http://swift.cmbi.ru.nl/gv/dssp/

2. Place in the Bin folder

3. Give permission to execute (Right click -> properties -> Allow executable)

4. Add export path in "bashrc" file

Please follow the steps:

sudo wget ftp://ftp.cmbi.ru.nl/pub/software/dssp/dssp-2.0.4-linux-amd64 -O /usr/local/bin/dssp

or

sudo wget ftp://ftp.cmbi.ru.nl/pub/software/dssp/dssp-2.0.4-linux-i386 -O /usr/local/bin/dssp

Then:

sudo chmod a+x /usr/local/bin/dssp

i use from commands but when i want check secondary structure with this command:

do_dssp -f traj.xtc -s topol.tpr -o secondary-structure.xpm -sc secondary-structure.xvg -dt 10

i got this error:do-dssp not found

thanks for your guidance. after use from dssp i have a file which name is secondary structure's and its blur.how i can analyse this?