# "Assertion failed" error when running the BAR command

**URL:** <https://gromacs.bioexcel.eu/t/assertion-failed-error-when-running-the-bar-command/2485>\
**Category:** User discussions\
**Created:** [July 9, 2021, 3:40pm UTC](https://gromacs.bioexcel.eu/t/assertion-failed-error-when-running-the-bar-command/2485 "2021-07-09T15:40:49Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![tom.stavert](https://avatars.discourse-cdn.com/v4/letter/t/ac91a4/32.png) [@tom.stavert](https://gromacs.bioexcel.eu/u/tom.stavert)\
**Post date:** [July 9, 2021, 3:40pm UTC](https://gromacs.bioexcel.eu/t/assertion-failed-error-when-running-the-bar-command/2485/1 "2021-07-09T15:40:49Z")

</div>

GROMACS version: 2021.2  
GROMACS modification: No

Hi all,

I’ve encountered an issue running the bar command. This error appears to get thrown regardless of the system used (I’ve tried two completely unrelated systems and it generates the same error). The input xvg files don’t appear to be the problem as they run fine on a colleagues computer. This is the first time I’ve used the bar command since installing GROMACS, but I’ve not had any issues with other commands. Operating system is Linux (Ubuntu 20.04). I’ve tried recompiling GROMACS but got the same error, I think its probably not a problem with GROMACS itself but if someone could point me in the right direction to fix it that would be much appreciated. Output below:

GROMACS: gmx bar, version 2021.2  
Executable: /usr/local/bin/gmx  
Data prefix: /usr/local  
Working dir: /home/tom/Desktop/Silica Research/Task 2: Solvating Arginine/ARG3\_OPLS/Free Energy/LJ  
Command line:  
gmx bar -f prod000.xvg prod020.xvg prod040.xvg prod060.xvg prod080.xvg prod090.xvg prod100.xvg -o bar.xvg -b 500 -prec 4

prod000.xvg: Ignoring set ‘pV (kJ/mol)’.

* * *

Program: gmx bar, version 2021.2  
Source file: src/gromacs/gmxana/gmx\_bar.cpp (line 745)  
Function: sample\_coll\_insert\_sample(sample\_coll\_t\*, samples\_t\*, sample\_range\_t\*)::\<lambda()\>

Assertion failed:  
Condition: sc-\>next-\>s  
Next not properly initialized!

For more information and tips for troubleshooting, please check the GROMACS  
website at [Errors - Gromacs](http://www.gromacs.org/Documentation/Errors)

Thanks  
Tom

---

<div class="post-metadata">

**Author:** ![jean](https://avatars.discourse-cdn.com/v4/letter/j/fbc32d/32.png) [@jean](https://gromacs.bioexcel.eu/u/jean)\
**Post date:** [September 30, 2021, 8:54am UTC](https://gromacs.bioexcel.eu/t/assertion-failed-error-when-running-the-bar-command/2485/2 "2021-09-30T08:54:55Z")

</div>

Hi Tom, hi all,

I have the same problem. GROMACS Version is2021.2 too.  
Was anyone able to solve or replicate this behaviour? Does it still occur with 2021.3?

Program: gmx bar, version 2021.2  
Source file: src/gromacs/gmxana/gmx\_bar.cpp (line 745)  
Function: sample\_coll\_insert\_sample(sample\_coll\_t\*, samples\_t\*, sample\_range\_t\*)::\<lambda()\>

Assertion failed:  
Condition: sc-\>next-\>s  
Next not properly initialized!

Thanks and best to you all!  
Jean

---

<div class="post-metadata">

**Author:** ![jean](https://avatars.discourse-cdn.com/v4/letter/j/fbc32d/32.png) [@jean](https://gromacs.bioexcel.eu/u/jean)\
**Post date:** [October 18, 2021, 7:58am UTC](https://gromacs.bioexcel.eu/t/assertion-failed-error-when-running-the-bar-command/2485/3 "2021-10-18T07:58:12Z")

</div>

Hi,

not solved but it seems to be an issue of 2021.2. 2012.3 and 2012.1 can handle the same files without this error occuring.

Best  
Jean