# Unexplained harp error with v1.17
**URL:** https://forum.atmospherictoolbox.org/t/unexplained-harp-error-with-v1-17/647
**Category:** HARP
**Tags:** python
**Created:** [May 16, 2023, 11:17am UTC](https://forum.atmospherictoolbox.org/t/unexplained-harp-error-with-v1-17/647 "2023-05-16T11:17:59Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@mariliza](https://forum.atmospherictoolbox.org/u/mariliza)
#### Post date: [May 16, 2023, 11:17am UTC](https://forum.atmospherictoolbox.org/t/unexplained-harp-error-with-v1-17/647/1 "2023-05-16T11:17:59Z")
Dear Sander,
I am encountering a harp error, via python, on a code that I was using back in February. The code is attached to the end of this message. It reads, via coda, the NASA OMI L2G daily product and outputs in harp-compliant form gridded monthly data. Nothing fancy. I repeat, this was working in February, with the previous harp version.
The error is :
_File ~/.conda/envs/myCondaEnvName/lib/python3.9/site-packages/harp/\_harppy.py:1110 in \_export\_product_
- \_export\_variable(name, product[name], c\_product)\*
- File ~/.conda/envs/myCondaEnvName/lib/python3.9/site-packages/harp/\_harppy.py:1068 in \_export\_variable\*
- raise CLibraryError()\*
_CLibraryError: invalid unit ‘degree\_north’_
_During handling of the above exception, another exception occurred:_
_Traceback (most recent call last):_
- File ~/.conda/envs/myCondaEnvName/lib/python3.9/site-packages/spyder\_kernels/py3compat.py:356 in compat\_exec\*
- exec(code, globals, locals)\*
- File /mnt/lapsat/groups/lapsat/OMI\_SO2/Programs/harp\_convert\_OMI\_L3.py:99\*
- average = harp.execute\_operations(productlist,\*
- File ~/.conda/envs/myCondaEnvName/lib/python3.9/site-packages/harp/\_harppy.py:1517 in execute\_operations\*
- \_export\_product(product, c\_product\_ptr[0])\*
- File ~/.conda/envs/myCondaEnvName/lib/python3.9/site-packages/harp/\_harppy.py:1112 in \_export\_product\*
- raise Error(“variable ‘%r’ could not be exported (%s)” % (name, str(\_error)))\*
_Error: variable ‘‘latitude’’ could not be exported (invalid unit ‘degree\_north’)_
My conda env only contains module via the conda forge channel, and is a dedicated harp env. Conda list replies, for harp & coda:
_harp 1.17 py39r42h92210e6\_0 conda-forge_
_coda 2.24.1 py39h92210e6\_0 conda-forge_
I am running the script on spyder with
\*Python 3.9.15 | packaged by conda-forge | (main, Nov 22 2022, 15:55:03) \*
_Type “copyright”, “credits” or “license” for more information._
_IPython 8.8.0 – An enhanced Interactive Python._
Any ideas on how this may be going wrong?
Many thanks
MariLiza
#!/usr/bin/env python3
# -_- coding: utf-8 -_-
“”"
Created on Thu Jun 25 12:06:13 2020
@author: mariliza
“”"
import coda
import harp
import numpy
import os
import calendar
from datetime import datetime, date
import sys
import numpy as np
import fnmatch
#from os import listdir
# twelve months
mon = [i+1 for i in range(12)]
matchex = [“%02d” %x for x in mon]
# local variables
path = ‘/mnt/lapsat/groups/lapsat/OMI\_SO2/EvenMoreData/’
outpath = ‘/mnt/lapsat/groups/lapsat/OMI\_SO2/HARP\_EvenMoreData/’
# output directory
if not os.path.exists(outpath):
os.makedirs(outpath)
# load all the filenames
filenames =
for file in os.listdir(path):
if file.endswith(“.he5”):
filenames.append(file)
filenames.sort()
# loop in months
for minas in range(len(matchex)):
```
productlist = []
# locate only the files within that month
allfilenames = []
for ffile in filenames: #os.listdir(folder):
# if fnmatch.fnmatch(ffile.decode(encoding='utf-8'), str('*2021m'+matchex[minas]+'*')):
if fnmatch.fnmatch(ffile, str('OMI-Aura_L3-OMSO2e_2023m'+matchex[minas]+'*')):
allfilenames.append(os.fsdecode(ffile))
if len(allfilenames) == 0:
continue
allfilenames.sort()
# read in all the files in that month
for ffile in allfilenames:
filename = os.fsdecode(ffile)
infile = path+filename
print(infile)
pf = coda.open(infile)
try:
latitude = coda.fetch(pf, 'HDFEOS/GRIDS/OMI_Total_Column_Amount_SO2/Data_Fields/Latitude')
longitude = coda.fetch(pf, '/HDFEOS/GRIDS/OMI_Total_Column_Amount_SO2/Data_Fields/Longitude')
so2 = coda.fetch(pf, '/HDFEOS/GRIDS/OMI_Total_Column_Amount_SO2/Data_Fields/ColumnAmountSO2')
# so2_scd = coda.fetch(pf,'/HDFEOS/GRIDS/OMI_Total_Column_Amount_SO2/Data_Fields/SlantColumnAmountSO2')
time = coda.fetch(pf,'/HDFEOS/GRIDS/OMI_Total_Column_Amount_SO2/Data_Fields/Time')
so2_flag = coda.fetch(pf, '/HDFEOS/GRIDS/OMI_Total_Column_Amount_SO2/Data_Fields/QualityFlags_SO2')
sza = coda.fetch(pf, '/HDFEOS/GRIDS/OMI_Total_Column_Amount_SO2/Data_Fields/SolarZenithAngle')
# sys.exit()
finally:
coda.close(pf)
product = harp.Product()
lat = latitude[:,0]
lon = longitude[0,:]
product.latitude = harp.Variable(lat, ['latitude']) #, longitude'])
product.latitude.unit = 'degree_north'
product.longitude = harp.Variable(lon, ['longitude'])
product.longitude.unit = 'degree_east'
product.so2_column_number_density = harp.Variable(so2, ['latitude', 'longitude'])
product.so2_column_number_density.unit = 'DU'
# product.so2_slant_column_number_density = harp.Variable(so2_scd, ['latitude', 'longitude'])
# product.so2_slant_column_number_density.unit = 'DU'
product.time = harp.Variable(time, ['latitude', 'longitude'])
productlist.append(product)
average = harp.execute_operations(productlist,
operations='latitude>=-10.0;latitude<=50.0;longitude>=50.0;longitude<=170.0',
post_operations="bin();squash(time, (latitude,longitude))")
# sys.exit()
OutFile = outpath + '2023'+matchex[minas]+'.nc'
# filename[19:23] + filename[24:28] + '.nc'
harp.export_product(average, OutFile)
print(OutFile)
# sys.exit()
```
---
### Author:  [@sander.niemeijer](https://forum.atmospherictoolbox.org/u/sander.niemeijer)
#### Post date: [May 16, 2023, 11:38am UTC](https://forum.atmospherictoolbox.org/t/unexplained-harp-error-with-v1-17/647/2 "2023-05-16T11:38:29Z")
This might be because the udunits configuration files could not be found. Do you have a set of `udunits2*.xml` files in `~/.conda/envs/myCondaEnvName/share/harp`?
Or do you maybe have a `UDUNITS2_XML_PATH` environment variable set that points to a wrong location?
---
### Author:  [@mariliza](https://forum.atmospherictoolbox.org/u/mariliza)
#### Post date: [May 16, 2023, 11:50am UTC](https://forum.atmospherictoolbox.org/t/unexplained-harp-error-with-v1-17/647/3 "2023-05-16T11:50:35Z")
Yes, I do have a set of udinits2\*.xml files in my env
[mariliza@aristotle5 ~]$ ls ~/.conda/envs/myCondaEnvName/share/harp
doc udunits2-accepted.xml udunits2-base.xml udunits2-common.xml udunits2-derived.xml udunits2-prefixes.xml udunits2.xml
But you are right! The `UDUNITS2_XML_PATH` environment variable set that is in my \*bashrc file was pointing in the wrong direction. Our sysadmins were upgrading harp&coda for me to use with IDL and this was not updated.
I did not know that even though I am in my conda env, the udunits are picked from the \*bashrc. A bit strange to me, but I am no expert.
I reloaded everything, works fine. Many thanks!
MariLiza