A cheat sheet of foamDictionary commands for making quick command-line edits to OpenFOAM dictionaries

foamDictionary-cheat-sheet.md

foamDictionary Cheat Sheet

Accompanies OnCFD Newsletter #082: Quick edits with foamDictionary

Retrieve entries

# Print the top-level keywords present in this dictionary
foamDictionary system/snappyHexMeshDict -keywords

# Print the addLayersControls sub-dictionary
foamDictionary system/snappyHexMeshDict -entry addLayersControls

# List the keywords in the addLayersControls sub-dictionary
foamDictionary system/snappyHexMeshDict -keywords -entry addLayersControls

# Print the ENTRY for nLayerIter in addLayersControls
foamDictionary system/snappyHexMeshDict -entry addLayersControls/nLayerIter

# Print the VALUE of nLayerIter in addLayersControls
foamDictionary system/snappyHexMeshDict -entry addLayersControls/nLayerIter -value

Change an existing entry

# Set the value for nLayerIter in addLayersControls to 100
foamDictionary system/snappyHexMeshDict -entry addLayersControls/nLayerIter -set 100

# Set a value as the result of another command
# eg set the number of subdomains = to the number of procs on the machine
foamDictionary system/decomposeParDict -entry numberOfSubdomains -set $(nproc)

Add a new entry

# Add a new top-level entry with a vector
foamDictionary my-include-file -entry top-level-var -add "(1 2 3)"

# Add an empty sub-dictionary called newdict
foamDictionary my-include-file -entry newdict -add "{}"

# Add an entry called myvar into the newdict sub-dictionary
foamDictionary my-include-file -entry newdict/myvar -add 2000

# Add a complete sub-dictionary:
# eg. add a new geometry file into snappyHexMeshDict
foamDictionary system/snappyHexMeshDict -entry geometry/newgeom.obj \
  -add "{type triSurfaceMesh; name my-new-geometry;}"

Remove entries

# Remove the complete "newgeom.obj" sub-dictionary
foamDictionary system/snappyHexMeshDict -entry geometry/newgeom.obj -remove
	

Thank you for your nice document. It helps me a lot.

I found an interesting issue about the foamDictionary command. When you try to set a value on an existing dictionary with some macro, the command seems to expand all the macros at first and then set the value. Do you know how to avoid this?

Does foamDictionary -disableFunctionEntries do what you need?

Think you for your fast reply.
When I enable this flag, it will raise an error when dealing with the line containing "#eval{}". It says that the number of brackets does not match, while the blockMesh could make mesh without any error.

Ah, OK - yeah I can see this behaviour in some of the blockMesh tutorials.

Maybe you could raise it on the issue tracker?

Maybe you could extract some of the calculations into a separate dictionary & #include them back into your main dictionary?

Ah, actually the whole file is full of eval XD. So I choose to put the variable needed to be changed into a separate file. I’ll consider to raise it on the issue track. Thank you for your help! Get Outlook for iOS<https://aka.ms/o0ukef>

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________________________________ From: robinknowles ***@***.***> Sent: Tuesday, January 30, 2024 6:19:20 PM To: robinknowles ***@***.***> Cc: Comment ***@***.***> Subject: Re: robinknowles/foamDictionary-cheat-sheet.md @robinknowles commented on this gist.

________________________________ Ah, OK - yeah I can see this behaviour in some of the blockMesh tutorials. Maybe you could raise it on the issue tracker? Maybe you could extract some of the calculations into a separate dictionary & #include them back into your main dictionary? — Reply to this email directly, view it on GitHub<https://gist.github.com/robinknowles/e8171f17eb7d147eb092f1e9731a4f0b#gistcomment-4859183> or unsubscribe<https://github.com/notifications/unsubscribe-auth/AJPAVMFW3VXPHBAOAUHMO4DYRDCKRBFKMF2HI4TJMJ2XIZLTSKBKK5TBNR2WLJDUOJ2WLJDOMFWWLO3UNBZGKYLEL5YGC4TUNFRWS4DBNZ2F6YLDORUXM2LUPGBKK5TBNR2WLJDHNFZXJJDOMFWWLK3UNBZGKYLEL52HS4DFVRZXKYTKMVRXIX3UPFYGLK2HNFZXIQ3PNVWWK3TUUZ2G64DJMNZZDAVEOR4XAZNEM5UXG5FFOZQWY5LFVEYTCNBVGM4TCOBVU52HE2LHM5SXFJTDOJSWC5DF>. You are receiving this email because you commented on the thread. Triage notifications on the go with GitHub Mobile for iOS<https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android<https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>.