DensityEstimator.loss does not take sample_dim

[michaeldeistler]

In #1066, we had defined that log_prob and loss have the same input and output shapes:

density_estimator.log_prob(input, condition)

input: (sample_input, batch_input, *event_shape_input)
condition: (batch_condition, *event_shape_condition)
returns: (sample_input, batch_input)
raises: batch_input != batch_condition

However, for .loss, we are now removing the sample_dim. Therefore, the .loss function now has the following signature:

input: (batch_input, *event_shape_input)
condition: (batch_condition, *event_shape_condition)
returns: (batch_input)
raises: batch_input != batch_condition

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 77.01%. Comparing base (005aeac) to head (6ae9ede).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1149      +/-   ##
==========================================
- Coverage   85.09%   77.01%   -8.09%     
==========================================
  Files          90       90              
  Lines        6649     6643       -6     
==========================================
- Hits         5658     5116     -542     
- Misses        991     1527     +536     

Flag	Coverage Δ
unittests	77.01% <100.00%> (-8.09%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
sbi/inference/snle/mnle.py	85.00% <ø> (-8.48%)	⬇️
sbi/inference/snle/snle_base.py	93.61% <100.00%> (ø)
sbi/inference/snpe/snpe_base.py	89.02% <100.00%> (ø)
sbi/neural_nets/density_estimators/base.py	57.14% <ø> (ø)
.../neural_nets/density_estimators/categorical_net.py	98.03% <100.00%> (ø)
...nets/density_estimators/mixed_density_estimator.py	69.11% <100.00%> (ø)
sbi/neural_nets/density_estimators/nflows_flow.py	62.74% <100.00%> (ø)
sbi/neural_nets/density_estimators/zuko_flow.py	64.44% <100.00%> (ø)

... and 22 files with indirect coverage changes

[janfb]

Great! thanks for fixing this!
looks good, I added a couple of questions to clarify the changes.

You can run ruff check --fix sbi to fix the ruff errors.