Tevatron inclusive DY

[jacoterh]

This PR implements filter functions for the Tevatron inclusive DY datasets:

• CDF_Z0_1P96TEV_ZRAP: agreement with legacy implementation
• D0_WPWM_1P96TEV: agreement with legacy, except for possible rounding errors in the old implementation of the kinematics, see specifically the last two bins here
• D0_Z0_1P96TEV: agreement with legacy. One difference: systematic in 3rd bin is symmetric already on hepdata, while the legacy implementation seems to have symmetrised plus and minus uncertainties in the past here. This also affects the central value.

General comment: small overall differences are due to formatting. For example: 1.2999999999999998 instead of 1.3. Is there any function that was used in the past to uniform the way floats were formatted?

[Radonirinaunimi]

Thanks for this @jacoterh!

Small overall differences are due to formatting. For example: 1.2999999999999998 instead of 1.3. Is there any function that was used in the past to uniform the way floats were formatted?

Now, you can use this function:

nnpdf/nnpdf_data/nnpdf_data/filter_utils/utils.py

Lines 402 to 423 in bf8c890

	def prettify_float(dumper, value):
	"""
	Override the default yaml representer:
	https://github.com/yaml/pyyaml/blob/48838a3c768e3d1bcab44197d800145cfd0719d6/lib/yaml/representer.py#L189
	This function is used to prettify the float representation in the yaml file.
	If the float has more than 8 digits, it will be represented in scientific notation with 8 digits.
	Note:
	-----
	When importing yaml in a module,
	yaml.add_representer(float, prettify_float)
	must be called to use this function.
	"""
	ret = dumper.represent_float(value)
	if len(ret.value) > 8:
	ret_str = f"{value:.8e}"
	ret = dumper.represent_scalar('tag:yaml.org,2002:float', ret_str)
	return ret

and call it as follows in the filter:

nnpdf/nnpdf_data/nnpdf_data/commondata/ATLAS_1JET_8TEV_R06/filter.py

Line 7 in bf8c890

yaml.add_representer(float, prettify_float)

Also, same as in the other PRs, could you check that the datasets are loaded properly and that the (t0) covmats are the same?

from validphys.api import API
import numpy as np

inp1 = {"dataset_input": {"dataset": f"{new_implementation}"}, "theoryid": 40_000_000, "use_cuts": "internal", "t0pdfset": "NNPDF40_nnlo_as_01180", "use_t0": True}
inp2 = {"dataset_input": {"dataset": f"{old_implementation}", "variant": "legacy"}, "theoryid": 40_000_000, "use_cuts": "internal", "t0pdfset": "NNPDF40_nnlo_as_01180", "use_t0": True}

covmat1 = API.covmat_from_systematics(**inp1)
covmat2 = API.covmat_from_systematics(**inp2)

t0_covmat1 = API.t0_covmat_from_systematics(**inp1)
t0_covmat2 = API.t0_covmat_from_systematics(**inp2)

np.all(np.isclose(covmat1, covmat2))
np.all(np.isclose(t0_covmat1, t0_covmat2))

[scarlehoff]

Hi @jacoterh

Remember to put as process_type: one of the processes that you will find in this file: https://github.com/NNPDF/nnpdf/blob/master/validphys2/src/validphys/process_options.py (at the bottom, either DY_Z_Y or DY_W_ETA)

and also put kinematic_override: identity.

This is to avoid going through some old code that we are trying to remove.

When you do that you will see that that file defines which kinematic variables are allowed, sometimes it is necessary to change from Q -> Q^2 or pT -> pT^2 (the kinematic info in the end is the same, but we are trying to standardize it a bit more)

[jacoterh]

Ok, done!

[jacoterh]

Thanks @Radonirinaunimi! The numbers have been formatted correctly now. I have also performed the check you proposed using the snippet you provided, see for instance here . If you run this script, you'll find that the 3rd bin in D0_Z0_1P96TEV differs from the legacy implementation for the reason I mentioned in the beginning of this PR.

Some questions:

1. Why do the tests suddenly fail? Running pytest tests/test_datafiles.py locally works fine.
2. I explicitly checked whether the comparison against the legacy implementation failed when I randomly changed some numbers. It did for all datasets, except for the 1st bin in D0_WPWM_1P96TEV. The test does neem to care about whatever I write here. This doesn't happen for the D0_Z0_1P96TEV and CDF_Z0_1P96TEV datasets.
3. In the metadata, which hepdata table do I link for the url in case multiple entered the implementation?

[scarlehoff]

The current failure is because it is plotting::kinematics_override (the probability that I get a variable name or word in general correct without looking in the first try is close to 0)

The previous one probably related to some change in digits looking at the logs.

[jacoterh]

validphys reports:

• legacy
• new commondata

observables = ["CDF_Z0_1P96TEV_ZRAP", "D0_WPWM_1P96TEV_ASY", "D0_Z0_1P96TEV_ZRAP"]

for obs in observables:

    new_implementation = obs
    old_implementation = obs

    inp1 = {
        "dataset_input": {"dataset": f"{new_implementation}"},
        "theoryid": 200,
        "use_cuts": "internal",
        "t0pdfset": "NNPDF40_nnlo_as_01180",
        "use_t0": True,
    }
    inp2 = {
        "dataset_input": {"dataset": f"{old_implementation}", "variant": "legacy"},
        "theoryid": 200,
        "use_cuts": "internal",
        "t0pdfset": "NNPDF40_nnlo_as_01180",
        "use_t0": True,
    }

    covmat1 = API.covmat_from_systematics(**inp1)
    covmat2 = API.covmat_from_systematics(**inp2)

    t0_covmat1 = API.t0_covmat_from_systematics(**inp1)
    t0_covmat2 = API.t0_covmat_from_systematics(**inp2)

    print(f"Comparison for {new_implementation}")
    print(np.all(np.isclose(covmat1, covmat2)))
    print(np.all(np.isclose(t0_covmat1, t0_covmat2)))

>>> Comparison for CDF_Z0_1P96TEV_ZRAP
True
True
Comparison for D0_WPWM_1P96TEV_ASY
True
True
Comparison for D0_Z0_1P96TEV_ZRAP
False
False

The last disagreement in D0_Z0_1P96TEV_ZRAP can be explained as follows. The systematic uncertainty in the 3rd bin appears symmetric already on hepdata, while the legacy implementation seems to have symmetrised plus and minus uncertainties in the past here. This also affects the central value.

[scarlehoff]

Thanks Jaco. One last thing, could you check that also the experimental covmat for the 3 datasets together doesn't change for non-diagonal entries?

(you can also e.g. just check that the experimental chi2 for all 3 considered together is unchanged)

(this will be important for the singletop data as well, to check that possible experimental correlations across datasets are also captured)

[jacoterh]

Sure, I made a plot of the ratio against the legacy implementation. There are no cross correlations between datasets here though (which I find odd as we have two datasets from D0), so the covmat is block diagonal meaning that the datasets can be cross checked separately. But I will also do this check for single top, where we do have cross correlations, thanks!

For reference, the ratio was obtained with

dsinps = [
        {'dataset': 'CDF_Z0_1P96TEV_ZRAP'},
        {'dataset': 'D0_WPWM_1P96TEV_ASY'},
        {'dataset': 'D0_Z0_1P96TEV_ZRAP'}
]

dsinps_legacy = [
        {'dataset': 'CDF_Z0_1P96TEV_ZRAP', 'variant': 'legacy'},
        {'dataset': 'D0_WPWM_1P96TEV_ASY', 'variant': 'legacy'},
        {'dataset': 'D0_Z0_1P96TEV_ZRAP', 'variant': 'legacy'}
]

inp = dict(dataset_inputs=dsinps, theoryid=200, use_cuts="internal")
inp_legacy = dict(dataset_inputs=dsinps_legacy, theoryid=200, use_cuts="internal")
cov = API.dataset_inputs_covmat_from_systematics(**inp)
cov_legacy = API.dataset_inputs_covmat_from_systematics(**inp_legacy)

[scarlehoff]

Hi @jacoterh

Thanks for this. All seems fine, the only thing, could you bump the version and change the version_comment in the metadata.yml files?

RE the failing test, you might need to regenerate pseudodata_test_fit_n3fit_240916. Since it is only the pseudodata that is relevant, you can just do:

vp-fitrename pseudodata_test_fit_n3fit_240916 pseudodata_test_fit_n3fit_241112
cp pseudodata_test_fit_n3fit_241112/filter.yaml  pseudodata_test_fit_n3fit_241112.yaml

And then just regenerate the data for the 10 replicas, no need to wait until the fit is done.