Programs used to perform the conversion from idf file to inp format.
Both .idf and .inp files are from Autodesk software, but it doesn't seem very likely that some kind of direct idf to inp conversion is possible, due to he difference of nature of both file types. Both contain some kind of parameters or settings and not CAD drawing.
But of course if you think such conversion or export is doable, it would be best to contact Autodesk support or some online community.
Updated: January 25, 2023
Unfortunately, there is no detailed software record in the database for this conversion.
Additional links: Open idf file, Open inp file
IDF
An idf file extension is related to the InspireData and used for its data files.
Files with idf extension are used for AutoCAD Civil 3D developed by Autodesk company. They include some graphic data.
Files with idf file extension are related to the CircuitWorks Intermediate Data Format.
INP
Files with inp file extension can be found as various GIS (geographic information system) input files. Text based format.
Files with inp extension might also be found as documents prepared using the InPage Urdu software.
Files with inp extension might also be found as source codes for some Oracle software solution.
An inp file extension is related to the gretl, a software for Windows and Mac OS X. An inp file stores script.
Files with inp file extension can also be found in some HD digital cameras and camcorders from Sony. These files server internal purpose of the devices.
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