# Can dynamo fill in parameter values? **URL:** \ **Category:** Revit\ **Created:** [February 28, 2017, 5:59pm UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971 "2017-02-28T17:59:52Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![bharlow1986](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@bharlow1986](https://forum.dynamobim.com/u/bharlow1986)\ **Post date:** [February 28, 2017, 5:59pm UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971/1 "2017-02-28T17:59:53Z")
I recently was able to get dynamo to select certain elements with a certain parameter. Is there a way to run dynamo to fill in the text value for that specific parameter? such as a different number value for each instance i have? if this is possible are we able to add a common prefix to all the numbers added? I have attached what i have so far. Thanks! ![](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/8/3/839a45c662b5e334294988e70bc9e2415dc1b4f3.png) ---
**Author:** ![bmsewell](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/bmsewell/32/17073_2.png) [@bmsewell](https://forum.dynamobim.com/u/bmsewell)\ **Post date:** [February 28, 2017, 8:37pm UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971/2 "2017-02-28T20:37:52Z")
You can use the Element.SetParameterByName node to write a new value to that element. ![](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/4/6/467a88585740d30c4323e0833392bb71b82841c6.PNG) ---
**Author:** ![bharlow1986](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@bharlow1986](https://forum.dynamobim.com/u/bharlow1986)\ **Post date:** [March 1, 2017, 9:30pm UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971/3 "2017-03-01T21:30:10Z")
Wow @bmsewell u really simplified what i had. For some reason when i do the final connection it begins to process and then causes my dynamo and revit to crash. Can u explain the Prefix code block to me? when i input the “x” i get different options, should i select one of these? ---
**Author:** ![jacob.small](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/jacob.small/32/161030_2.png) [@jacob.small](https://forum.dynamobim.com/u/jacob.small)\ **Post date:** [March 1, 2017, 10:16pm UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971/4 "2017-03-01T22:16:53Z")
THe prefix code block is inserting the string “Pre-Fab Box#” before the existing parameter value for “Pre-Fab Box#”. Simplify it further by wiring the left most **All Elements of Category** node into the element input for the **ELement.SetParamterByName**. How large is your dataset (number of electrical fixtures in this case)? ---
**Author:** ![bharlow1986](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@bharlow1986](https://forum.dynamobim.com/u/bharlow1986)\ **Post date:** [March 2, 2017, 2:54pm UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971/5 "2017-03-02T14:54:22Z")
Its very small, im using a test project with 25 electrical fixtures and only 13 have the “Pre-Fab Box#” parameter. I was hoping to get this working and be able to use it for a few hundred fixtures in an actual project. I cant figure out what dynamo doesnt like here to cause the crash. Could it be because the parameter is a created shared parameter? ---
**Author:** ![bharlow1986](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@bharlow1986](https://forum.dynamobim.com/u/bharlow1986)\ **Post date:** [March 2, 2017, 3:19pm UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971/6 "2017-03-02T15:19:13Z")
So i changed the run to manual and i have my prefixes working. Getting an error for the set parameter by name. It is saying no parameter found by that name. ---
**Author:** ![bmsewell](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/bmsewell/32/17073_2.png) [@bmsewell](https://forum.dynamobim.com/u/bmsewell)\ **Post date:** [March 2, 2017, 3:24pm UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971/7 "2017-03-02T15:24:59Z")
Make sure the code block that contains the name of the parameter that you are trying to set matches exactly how it appears in Revit. It is case sensitive. ---
**Author:** ![bharlow1986](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@bharlow1986](https://forum.dynamobim.com/u/bharlow1986)\ **Post date:** [March 2, 2017, 3:32pm UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971/8 "2017-03-02T15:32:28Z")
Just verified that and it looks good. Could it be that i need to filter out the Electrical Fixtures that do not contain that parameter before connecting to the set parameter by name? ![](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/2/9/299e88ed7d5a8e8bfc305e1bca0c2a73290e6309.png) ---
**Author:** ![bmsewell](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/bmsewell/32/17073_2.png) [@bmsewell](https://forum.dynamobim.com/u/bmsewell)\ **Post date:** [March 2, 2017, 3:33pm UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971/9 "2017-03-02T15:33:19Z")
Yes, that should work. ---
**Author:** ![bharlow1986](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@bharlow1986](https://forum.dynamobim.com/u/bharlow1986)\ **Post date:** [March 2, 2017, 4:07pm UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971/10 "2017-03-02T16:07:53Z")
Would i use a list clean somewhere? ---
**Author:** ![bmsewell](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/bmsewell/32/17073_2.png) [@bmsewell](https://forum.dynamobim.com/u/bmsewell)\ **Post date:** [March 2, 2017, 4:46pm UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971/11 "2017-03-02T16:46:50Z")
You can filter the elements by the parameter value. Remove all elements from the list where the value is null. ![](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/b/1/b1c44f727f93b6ed88e05b15e41e2dfd964211db.png) ---
**Author:** ![bharlow1986](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@bharlow1986](https://forum.dynamobim.com/u/bharlow1986)\ **Post date:** [March 2, 2017, 7:37pm UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971/12 "2017-03-02T19:37:05Z")
Hmm cant seem to get it to filter. Still seeing my null values for some reason. ---
**Author:** ![m.ridi220](https://avatars.discourse-cdn.com/v4/letter/m/9d8465/32.png) [@m.ridi220](https://forum.dynamobim.com/u/m.ridi220)\ **Post date:** [September 2, 2019, 8:42am UTC](https://forum.dynamobim.com/t/can-dynamo-fill-in-parameter-values/9971/13 "2019-09-02T08:42:43Z")
> [@bharlow1986](#): > > You can use the Element.SetParameterByName node to write a new value to that element. [write a parameter’s value.dyn](https://forum.dynamobim.com/uploads/short-url/iysdOcWwwmo7drJxFH7uG50OFMu.dyn) (15.8 KB) @bmsewell I copied your flow but I get the following error: “NO paramter founf by that name”. Can you help me please?