Nonallocating noncacheing

[aabills]

Description

Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context. List any dependencies that are required for this change.

Fixes # (issue)

Type of change

Please add a line in the relevant section of CHANGELOG.md to document the change (include PR #) - note reverse order of PR #s. If necessary, also add to the list of breaking changes.

• New feature (non-breaking change which adds functionality)
• Optimization (back-end change that speeds up the code)
• Bug fix (non-breaking change which fixes an issue)

Key checklist:

• No style issues: $ flake8
• All tests pass: $ python run-tests.py --unit
• The documentation builds: $ cd docs and then $ make clean; make html

You can run all three at once, using $ python run-tests.py --quick.

Further checks:

• Code is commented, particularly in hard-to-understand areas
• Tests added that prove fix is effective or that feature works

Will probably need a few more tests

[codecov]

Codecov Report

Base: 99.72% // Head: 99.04% // Decreases project coverage by -0.67% ⚠️

Coverage data is based on head (67f423f) compared to base (4127bd1).
Patch coverage: 83.70% of modified lines in pull request are covered.

❗ Current head 67f423f differs from pull request most recent head b39b8e0. Consider uploading reports for the commit b39b8e0 to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #2409      +/-   ##
===========================================
- Coverage    99.72%   99.04%   -0.68%     
===========================================
  Files          268      268              
  Lines        20153    20535     +382     
===========================================
+ Hits         20097    20339     +242     
- Misses          56      196     +140     

Impacted Files	Coverage Δ
pybamm/util.py	100.00% <ø> (ø)
pybamm/expression_tree/state_vector.py	87.05% <18.18%> (-12.95%)	⬇️
...ybamm/expression_tree/operations/evaluate_julia.py	85.20% <85.09%> (-14.80%)	⬇️
pybamm/models/base_model.py	98.56% <100.00%> (+0.03%)	⬆️
pybamm/simulation.py	99.77% <0.00%> (-0.23%)	⬇️

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[aabills]

Closing in favor of #2453