Add new DES-Dovekie SN release (#465)

* Create desdovekie.py

Initial commit for updated SN-likelihood for use in DES-Dovekie.

* Update sn.py

Added a new method to read new updated inverse covariance matrices for SN

* Initial slate of corrections to get DES-Dovekie to work

* sn.py updated to point at sn_data v1.8

* Update test_cosmo_sn.py

Author: bap37

cobaya/cosmo_input/input_database.py

@@ -838,6 +838,11 @@
         "theory": theory,
         "likelihood": {"sn.desy5": None},
     },
+    "DESDovekie": {
+        "desc": "Supernovae data from the updated DES-Dovekie Y5 sample",
+        "theory": theory,
+        "likelihood": {"sn.desdovekie": None},
+    },
     "Pantheon": {
         "desc": "Supernovae data from the Pantheon sample",
         "theory": theory,

cobaya/likelihoods/base_classes/sn.py

@@ -53,7 +53,7 @@ class SN(DataSetLikelihood):
 
     install_options = {
         "github_repository": "CobayaSampler/sn_data",
-        "github_release": "v1.6",
+        "github_release": "v1.8",
     }
 
     use_abs_mag: bool = False
@@ -228,6 +228,18 @@ def get_requirements(self):
             reqs["Mb"] = None
         return reqs
 
+    def _read_inv_covmat(self, filename):
+        d = np.load(filename)
+        n = d[d.files[0]][0]
+        inv_cov = np.zeros((n, n))
+        inv_cov[np.triu_indices(n)] = d[d.files[1]]
+
+        # Reflect to lower triangular part to make it symmetric
+        i_lower = np.tril_indices(n, -1)
+        inv_cov[i_lower] = inv_cov.T[i_lower]
+
+        return inv_cov
+
     def _read_covmat(self, filename):
         cov = np.loadtxt(filename)
         if np.isscalar(cov[0]) and cov[0] ** 2 + 1 == len(cov):

cobaya/likelihoods/sn/desdovekie.py

@@ -0,0 +1,37 @@
+import os
+
+from .pantheonplus import PantheonPlus
+
+
+class DESDovekie(PantheonPlus):
+    """
+    Likelihood for DES-Dovekie type Ia supernovae sample.
+
+    Reference
+    ---------
+    https://arxiv.org/abs/2511.07517
+    """
+
+    def _read_data_file(self, data_file):
+        file_cols = ['idsurvey', 'zhd', 'zhel', 'mu', 'muerr', 'muerr_vpec', 'muerr_sys', 'probia_beams']
+        self.cols = ['idsurvey', 'zcmb', 'zhel', 'mag', 'magerr', 'magerr_vpec', 'magerr_sys', 'probia_beams']
+        self._read_cols(data_file, file_cols, sep=",")
+
+        
+    def init_params(self, ini):
+
+        self.twoscriptmfit = False
+        data_file = os.path.normpath(os.path.join(self.path, ini.string("data_file")))
+        self._read_data_file(data_file)
+        self.covs = {}
+        for name in ["mag"]:
+            self.log.debug("Reading inverse covmat for: %s " % name)
+            self.invcov = self._read_inv_covmat(
+                os.path.join(self.path, ini.string("%s_covmat_file" % name))
+            )
+        self.alphabeta_covmat = False
+        self.configure()
+        if not self.use_abs_mag:
+            self._marginalize_abs_mag()
+        self.marginalize = False
+

cobaya/likelihoods/sn/desdovekie.yaml

@@ -0,0 +1,15 @@
+# Settings for the DES-Dovekie SN Ia analysis.
+
+# Path to the data: where the sn_data has been cloned
+path: null
+# .dataset file with settings
+dataset_file: DES-Dovekie/config.dataset
+# Overriding of .dataset parameters
+dataset_params:
+  # field: value
+# Aliases for automatic covariance matrix
+aliases: [DESDovekie]
+# Use absolute magnitude
+use_abs_mag: False
+# Speed in evaluations/second
+speed: 100

tests/test_cosmo_sn.py

@@ -115,6 +115,11 @@ def test_sn_desy5_camb(packages_path, skip_not_installed):
     _test_sn(packages_path, skip_not_installed, "sn.desy5")
 
 
+def test_sn_desdovekie_camb(packages_path, skip_not_installed):
+    _test_sn(packages_path, skip_not_installed, "sn.desdovekie")
+
+
+    
 # BEST FIT AND REFERENCE VALUES ##########################################################
 
 best_fit = deepcopy(params_lowTEB_highTTTEEE)
@@ -130,4 +135,6 @@ def test_sn_desy5_camb(packages_path, skip_not_installed):
     "sn.pantheonplusshoes": 1496.97,
     "sn.union3": 26.31,
     "sn.desy5": 1644.94,
+    "sn.desdovekie":1632.35,
+    
 }