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IDF file sometimes runs and sometimes doesn't (diff on both idf text files outputs no difference)

asked 2018-07-20 14:08:13 -0600

mldichter's avatar

I have an IDF file with some strange behavior. I have two versions of the exact same idf file (I ran diff on the txt files and there is no difference) with the exact same weather file, but one runs and one has a severe error.

Here they are. Google Drive link

The err file in the folder that has severe error is

Program Version,EnergyPlus, Version 8.9.0-eba93e8e1b, YMD=2018.07.20 11:58,
   ** Severe  ** <root> - Object required to validate 'required' properties.
   **  Fatal  ** Errors occurred on processing input file. Preceding condition(s) cause termination.
   ...Summary of Errors that led to program termination:
   ..... Reference severe error count=1
   ..... Last severe error=<root> - Object required to validate 'required' properties.
   ************* Warning:  Node connection errors not checked - most system input has not been read (see previous warning).
   ************* Fatal error -- final processing.  Program exited before simulations began.  See previous error messages.
   ************* EnergyPlus Warmup Error Summary. During Warmup: 0 Warning; 0 Severe Errors.
   ************* EnergyPlus Sizing Error Summary. During Sizing: 0 Warning; 0 Severe Errors.
   ************* EnergyPlus Terminated--Fatal Error Detected. 0 Warning; 1 Severe Errors; Elapsed Time=00hr 00min  0.19sec

I can usually get the severe error to go away by opening the idf file with the idf editor, making any new object, deleting said object, and saving the idf again.

This isn't the only funny thing this idf file has done, but I managed to reproduce this behavior. The misbehaving idf file is based on the example file 5ZoneFanCoilDOAS_ERVOnAirLoopMainBranch.idf, with the purchased heating and cooling replaced with a boiler and chiller.

Energyplus 8.9.0

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@mldichter Are you running under Linux or MacOS?

Avi's avatar Avi  ( 2018-07-23 12:29:38 -0600 )edit

@Avi Neither. My OS, as well another computer I tested, are Windows 10 Pro.

mldichter's avatar mldichter  ( 2018-07-23 12:34:02 -0600 )edit

@Avi Are you able to reproduce the error on your own computer?

mldichter's avatar mldichter  ( 2018-07-23 12:34:25 -0600 )edit

@mldichter Would you please let me know what you did to have this error fixed?

I'm receiving the same error while running the IDF file using EP Launch and through MATLAB!

* Severe * <root> - Object required to validate 'required' properties. * Fatal * Errors occurred on processing input file. Preceding condition(s) cause termination.


Mohammad's avatar Mohammad  ( 2021-01-04 03:30:11 -0600 )edit

@Mohammad The fix I used is in my original post. I was trying to figure out why it happened rather than simply how to fix the error. @Avi cited file encoding, but I never got a conclusive test back from him, just a belief.

mldichter's avatar mldichter  ( 2021-01-04 11:32:57 -0600 )edit

1 Answer

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answered 2018-07-23 13:22:42 -0600

Avi's avatar

updated 2018-07-25 15:41:02 -0600

mldichter's avatar

The problem is the encoding of the files. The one that is good looks like that on my computer: image description

And the one that fails:

image description

To prove it try to select all text an paste it into the file that doesn't completes and you will see that the error will stay.

It is probably an issue worth reporting.

Summary of Comments added by @mldichter:
Energyplus is picky about the encoding of the file. Encoding "UTF-8 (BOM)" does not run, but encoding "UTF-8 without BOM" does run. You can change the encoding of the file easily using Notepad++.

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@Avi Please post a download link to the idf file with the encoding that works. I'd like to try it out on my machine and investigate further what Windows 10 is doing. It sounds like it might be a problem with the default text editor rather than Energyplus, and I'd like to check before reporting it to the developers.

mldichter's avatar mldichter  ( 2018-07-23 13:43:20 -0600 )edit

@mldichter what you see in my answer are your original files. I changed the name of the file with the error since I was suspecting that the name caused the problem which I found to be wrong. As I mentioned in your other post the ANSI 1255 is my default encoding in my PC. So to conclude using the PC default encoding seems to work fine with E+ on the other hand using UTF-8 (BOM) fails on computer with different default encoding. I sow similar problems regarding EPW files encoding.

Avi's avatar Avi  ( 2018-07-23 23:22:02 -0600 )edit

@Avi Okay. Looks like I misunderstood. Just to clarify, the two idf files appear to have exactly the same data in them. However, on your computer, one idf runs without producing errors while the other idf file runs with a severe error. This leads you to conclude that something weird is going on with the two, supposedly identical, idf files that is independent of the computer running those idf files. Correct?

mldichter's avatar mldichter  ( 2018-07-24 10:21:43 -0600 )edit

@Avi I looked up ANSI-1255. It is used for writing Hebrew characters. Just wanted to check with you that your computer being setup to write Hebrew in text files is plausible. Is that correct? Otherwise, maybe whoever wrote the example energyplus 8.9 example idf file saved it with the ANSI-1255 encoding. Just want to rule out that possibility.

mldichter's avatar mldichter  ( 2018-07-24 10:27:40 -0600 )edit

@mldichter Yep my computer defaults to Hebrew. What I did was to open the file that was failing for you (from the Severe error folder) delete all its content and then paste the content of the one in the completes folder. And yet it was failing which led me to look at the encoding.

Avi's avatar Avi  ( 2018-07-24 10:51:11 -0600 )edit

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Asked: 2018-07-20 14:08:13 -0600

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Last updated: Jan 04 '21