# Question about the output of species for CMAQ-DDM v5.3.2

**URL:** <https://forum.cmascenter.org/t/question-about-the-output-of-species-for-cmaq-ddm-v5-3-2/3456>\
**Category:** CMAQ-DDM-3D\
**Tags:** cmaq\
**Created:** [July 29, 2022, 2:27am UTC](https://forum.cmascenter.org/t/question-about-the-output-of-species-for-cmaq-ddm-v5-3-2/3456 "2022-07-29T02:27:12Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Polaris](https://avatars.discourse-cdn.com/v4/letter/p/7ab992/32.png) [@Polaris](https://forum.cmascenter.org/u/Polaris)\
**Post date:** [July 29, 2022, 2:27am UTC](https://forum.cmascenter.org/t/question-about-the-output-of-species-for-cmaq-ddm-v5-3-2/3456/1 "2022-07-29T02:27:12Z")

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Hi everyone,  
I am still a beginner in using CMAQ-DDM-3D and I have run successfully the CMAQ\_v532\_DDM-3D. But i meet some trouble when i want to export only part of the species. If i set the CONC\_SPCS only O3, DDM-3D sensitivity output files will not in the output directory(CTM\_SENS\_1, A\_SENS\_1).

Does DDM have to export all species? What should I do if I want to export only part of the species?

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**Author:** ![FengLiu](https://avatars.discourse-cdn.com/v4/letter/f/49beb7/32.png) [@FengLiu](https://forum.cmascenter.org/u/FengLiu)\
**Post date:** [July 29, 2022, 6:22am UTC](https://forum.cmascenter.org/t/question-about-the-output-of-species-for-cmaq-ddm-v5-3-2/3456/2 "2022-07-29T06:22:29Z")

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Hi Polaris,

I do not think CMAQ v5.3.x includes DDM function. Please see [CMAQ-DDM for v5.3.3 - #2 by foley.kristen](https://forum.cmascenter.org/t/cmaq-ddm-for-v5-3-3/3373/2).

Thanks

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**Author:** ![sergey](https://avatars.discourse-cdn.com/v4/letter/s/9fc348/32.png) [@sergey](https://forum.cmascenter.org/u/sergey)\
**Post date:** [August 2, 2022, 2:51pm UTC](https://forum.cmascenter.org/t/question-about-the-output-of-species-for-cmaq-ddm-v5-3-2/3456/3 "2022-08-02T14:51:52Z")

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DDM uses the same subset instruction as the base concentrations. To subset the species, you need to change the “AVG\_CONC\_SPC” line in the runscript. If you are not getting sensitivity output files, check to see if your compiled the model with the right switch to enable DDM-3D.

Sergey