Hi everyone,

I read this article (https://www.nature.com/articles/ncomms15443) and I want to try the Action-CSA method.
In "Data availability", it is written that the Action-CSA code is freely available as a part of the CHARMM molecular dynamics package.

I just installed charmm with the command "./install.com gnu M".
Then I checked the /test/c36test directory after executing "./test.com gnu M 2" and read csatest.inp and csamin.inp in order to understand how to use CSA method.
However, these tests were not performed with the following message:

-----------
Maximum number of ATOMS: 360720, and RESidues: 120240
RDTITL> * CHARMM 36 TESTCASE CSATEST.INP
RDTITL> * TEST THE CSA MODULE
RDTITL> * AUTHOR: MILAN HODOSCEK
RDTITL> * THE SYSTEM OBTAINED FROM:
RDTITL> * WIKIPEDIA: TETRAPEPTIDE -> THE FIRST ON THE LIST
RDTITL> *

CHARMM>

CHARMM> if ?distene .ne. 1 then
RDCMND: can not substitute energy "?DISTENE"
Comparing "?DISTENE" and "1".
IF test evaluated as true. Performing command

CHARMM> echo "csatest.inp> Test NOT performed."
"csatest.inp> Test NOT performed."

CHARMM> stop
$$$$$$ New timer profile $$$$$
Total time 0.03 Other: 0.00

NORMAL TERMINATION BY NORMAL STOP
NO WARNINGS WERE ISSUED

$$$$$ JOB ACCOUNTING INFORMATION $$$$$
ELAPSED TIME: 0.03 SECONDS
CPU TIME: 0.03 SECONDS

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What is "distene" in this message and why is this test not performed?
What should I do to perform these tests and CSA calculation?

thanks