Update filter_mod.rst

[ann-norcio]

Description:

Corrected documentation for output_forward_op_errors output

Fixes issue

fixes #530

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Documentation changes needed?

• My change requires a change to the documentation.
  • I have updated the documentation accordingly.

Tests

subroutine verbose_forward_op_output:
do i = 1, ens_size
do j = 1, qc_ens_handle%my_num_vars
if(nint(qc_ens_handle%copies(i, j)) /= 0) write(forward_unit, *) i, keys(j), nint(qc_ens_handle%copies(i, j))
end do
end do

Checklist for merging

• Updated changelog entry
• Documentation updated
• Update conf.py

Checklist for release

• Merge into main
• Create release from the main branch with appropriate tag
• Delete feature-branch

Testing Datasets

• Dataset needed for testing available upon request
• Dataset download instructions included
• No dataset needed

[hkershaw-brown]

Hi Ann, your documentation looks good.
I think there is a bug in the actual code (see the comment)
so we'll take a look a this before merging your updated documentation.

@kdraeder local obs num or key, what do you think is best for debugging?

[hkershaw-brown]

thanks for this Ann,

Just looking at the issue #530 with the note on (local) observation number vs observation number

I think the code is incorrect too:

DART/assimilation_code/modules/assimilation/filter_mod.f90

Lines 2024 to 2029 in 6eeb453

	! qc_ens_handle is a real representing an integer; values /= 0 get written out
	do i = 1, ens_size
	do j = 1, qc_ens_handle%my_num_vars
	if(nint(qc_ens_handle%copies(i, j)) /= 0) write(forward_unit, *) i, keys(j), nint(qc_ens_handle%copies(i, j))
	end do
	end do

keys(j) is going print

keys(1)
keys(2)
keys(3)
...
for every process.

rather than the key for the local observation
keys(qc_ens_handle%my_vars(1))
keys(qc_ens_handle%my_vars(2))
keys(qc_ens_handle%my_vars(3))

I think the code should print:
j local observation number or
keys(qc_ens_handle%my_vars(j)) for the key

[ann-norcio]

Thanks Helen, missed that. Changed it so it prints keys(qc_ens_handle%my_vars(j))

https://github.com/NCAR/DART/pull/605/commits/1b7043eaaaf2ab62c7bd73f8af1ab48422ddd9f4

[hkershaw-brown]

need to decide whether to print local obs number or key.
The documentation and code need to match, which ever one we pick.

[hkershaw-brown]

A better solution from JLA:
print out both the local obs number and the key.

[hkershaw-brown]

A better solution from JLA:
print out both the local obs number and the key.

[hkershaw-brown]

Thanks for the changes Ann,
Couple of small fixes still needed
Cheers,
Helen

[hkershaw-brown]

dart style guide: 3 spaces for indenting code, so remove the extra spaces from the indenting.
remove the added whitespace a the ends of the lines also.

[hkershaw-brown]

local key is a misleading here. There is only a global key, so remove 'local'

Suggested change

	| | | for the local observation, and then the |
	| | | for the observation, and then the |

[ann-norcio]

Thanks Helen, made these changes.

[hkershaw-brown]

Looks good!
Prints out info, docs match the code, table all lined up nicely in .rst.

@hkershaw-brown bundle with next release