Emanuele Roberto Nocera · df8df5c3 · df8df5c3 · df8df5c3 · df8df5c3 · df8df5c3
--- a/n3fit/runcards/Basic_runcard.yml
+++ b/n3fit/runcards/Basic_runcard.yml
   positivity:
     multiplier: 1.05 # When any of the multiplier and/or the initial is not set
     initial: # the poslambda will be used instead to compute these values per dataset
+     threshold: 1e-5
--- a/n3fit/src/n3fit/checks.py
+++ b/n3fit/src/n3fit/checks.py
       if weight_freq < 0:
-           raise CheckError(f"The frequency at which weights are saved must be greater than 0, received {weight_freq}")
+           raise CheckError(
+               f"The frequency at which weights are saved must be greater than 0, received {weight_freq}"
+           )
+
+
+def check_lagrange_multipliers(parameters, key):
+   """Checks the parameters in a lagrange multiplier dictionary
+   are correct (positivity, integrability)"""
+   lagrange_dict = parameters.get(key)
+   if lagrange_dict is None:
+       return
+   multiplier = lagrange_dict.get("multiplier")
+   if multiplier is not None and multiplier <= 0:
+       log.warning("The %s multiplier is below 0, it will produce a negative loss", key)