# CMAQ-DDM Sensinput Reaction Rates **URL:** \ **Category:** CMAQ-DDM-3D\ **Created:** [June 7, 2021, 2:49pm UTC](https://forum.cmascenter.org/t/cmaq-ddm-sensinput-reaction-rates/2405 "2021-06-07T14:49:11Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![SharMM](https://avatars.discourse-cdn.com/v4/letter/s/96bed5/32.png) [@SharMM](https://forum.cmascenter.org/u/SharMM)\ **Post date:** [June 7, 2021, 2:49pm UTC](https://forum.cmascenter.org/t/cmaq-ddm-sensinput-reaction-rates/2405/1 "2021-06-07T14:49:11Z")
Hi, I have a question about the sensinput data. I would like generate separately sensitivities to multiple reaction rates, it works if define in one, but not as separate. Please advise. _ **Works** _\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* RATE1 RATE REACTION R1 R2 END _ **Does not Work** _\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* RATE1 RATE REACTION R1 RATE2 RATE REACTION R2 END ---
**Author:** ![sergey](https://avatars.discourse-cdn.com/v4/letter/s/9fc348/32.png) [@sergey](https://forum.cmascenter.org/u/sergey)\ **Post date:** [July 12, 2021, 3:32pm UTC](https://forum.cmascenter.org/t/cmaq-ddm-sensinput-reaction-rates/2405/2 "2021-07-12T15:32:21Z")
I don’t know of any reason for why this would be. I will try a test locally and get back to you. What model version are you running? ---
**Author:** ![SharMM](https://avatars.discourse-cdn.com/v4/letter/s/96bed5/32.png) [@SharMM](https://forum.cmascenter.org/u/SharMM)\ **Post date:** [July 12, 2021, 3:55pm UTC](https://forum.cmascenter.org/t/cmaq-ddm-sensinput-reaction-rates/2405/3 "2021-07-12T15:55:41Z")
I am using CMAQ 5.3.2 ---
**Author:** ![sergey](https://avatars.discourse-cdn.com/v4/letter/s/9fc348/32.png) [@sergey](https://forum.cmascenter.org/u/sergey)\ **Post date:** [July 12, 2021, 7:12pm UTC](https://forum.cmascenter.org/t/cmaq-ddm-sensinput-reaction-rates/2405/4 "2021-07-12T19:12:46Z")
I ran the following sensitivity input case on the benchmark data provided with the CMAQ release for 1 day: RT1 RATE REACTION R1 RT2 RATE REACTION R2 END I checked O3 output and there are values for all hours that seem reasonable. I believe this is your “Does not Work” scenario and its seems fine for me. How is the “Does not Work” situation manifested for you? ---
**Author:** ![sergey](https://avatars.discourse-cdn.com/v4/letter/s/9fc348/32.png) [@sergey](https://forum.cmascenter.org/u/sergey)\ **Post date:** [July 12, 2021, 7:13pm UTC](https://forum.cmascenter.org/t/cmaq-ddm-sensinput-reaction-rates/2405/5 "2021-07-12T19:13:54Z")
Note, that the forum does not preserve the required blank spaces in front of some lines in the input example above… ---
**Author:** ![SharMM](https://avatars.discourse-cdn.com/v4/letter/s/96bed5/32.png) [@SharMM](https://forum.cmascenter.org/u/SharMM)\ **Post date:** [July 22, 2021, 6:57pm UTC](https://forum.cmascenter.org/t/cmaq-ddm-sensinput-reaction-rates/2405/6 "2021-07-22T18:57:41Z")
Thank you @sergey. Defining sensitive coefficients are too sensitive 🙂 I have another question, when i run this it generates all sensitive coefficient as zero. Can you please advise why the coefficients are zero. ---
**Author:** ![sergey](https://avatars.discourse-cdn.com/v4/letter/s/9fc348/32.png) [@sergey](https://forum.cmascenter.org/u/sergey)\ **Post date:** [August 4, 2021, 10:12pm UTC](https://forum.cmascenter.org/t/cmaq-ddm-sensinput-reaction-rates/2405/7 "2021-08-04T22:12:10Z")
I did not get all zeros in my test. For one of them, the values were very small, but not zero. Sergey ---
**Author:** ![SharMM](https://avatars.discourse-cdn.com/v4/letter/s/96bed5/32.png) [@SharMM](https://forum.cmascenter.org/u/SharMM)\ **Post date:** [October 18, 2021, 2:57pm UTC](https://forum.cmascenter.org/t/cmaq-ddm-sensinput-reaction-rates/2405/8 "2021-10-18T14:57:58Z")
Hi Sergey, Sorry I have been bit away from the topic for a while. Now I am back to this to resolve. I mentioned to you that my run produces all sensitive coefficient as zero. This is strange, I tried running with different parameters, it produces SENS files but with zero coefficients. Also, I noticed that while running it give me the following message on the screen, notice that the times of COUPLE and DECOUPLE are 0.0 seconds. I am wondering If I forgot to turn on any switch in the settings. Your insight on this highly appreciated. Thanks, Mujtaba ``` VDIFF completed... 0.4 seconds COUPLE completed... 0.0 seconds HADV completed... 0.2 seconds ZADV completed... 0.1 seconds HDIFF completed... 0.0 seconds DECOUPLE completed... 0.0 seconds PHOT completed... 0.1 seconds CLDPROC completed... 0.2 seconds CHEM completed... 0.2 seconds AERO completed... 0.2 seconds ``` ---
**Author:** ![SharMM](https://avatars.discourse-cdn.com/v4/letter/s/96bed5/32.png) [@SharMM](https://forum.cmascenter.org/u/SharMM)\ **Post date:** [November 14, 2021, 5:18pm UTC](https://forum.cmascenter.org/t/cmaq-ddm-sensinput-reaction-rates/2405/9 "2021-11-14T17:18:05Z")
I am looking for help on this topic. I get all sensitivity coefficients to be zeros in CCTM\_ASENS file. Can someone provide insight on this. ---
**Author:** ![sergey](https://avatars.discourse-cdn.com/v4/letter/s/9fc348/32.png) [@sergey](https://forum.cmascenter.org/u/sergey)\ **Post date:** [November 18, 2021, 4:43pm UTC](https://forum.cmascenter.org/t/cmaq-ddm-sensinput-reaction-rates/2405/10 "2021-11-18T16:43:52Z")
I am not sure what is going on with your simulation. Have you tried simply running the base model without DDM and seeing if you can match the provided benchmark output?