Implement summation with limits using comprehension #30 #32
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This supports summation with limits (super/subscripts) written with comprehension with for loop and range function.
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Support for summation is pending and will be addressed after the following change. |
…torBase. Still WIP and needs refactoring
latexify/core.py
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| @@ -224,6 +244,27 @@ def visit_If(self, node, action): # pylint: disable=invalid-name | |||
| latex += self.visit(node) | |||
| return latex + r', & \mathrm{otherwise} \end{array} \right.' | |||
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| def visit_GeneratorExp_sum(self, node): # pylint: disable=invalid-name | |||
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This could have been implemented with generic visit_GeneratorExp, which might be useful for FRs in the future (ditto for visit_comprehension). In that case, we might need some additional checks in decorated_lstr_and_arg.
You could view the generic implementation in this commit (sorry it's a bit dirty before refactoring).
0c5d67f
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What are FRs?
This function can be reused with other operators (e.g., products and integrals have the same syntax). We can use some general action name rather than sum.
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I think the bare visitor (=visitor with None action) of every node should return only a LaTeX string. Otherwise every parent node is required to know what kind of objects are returned from children and how to process them to construct LaTeX strings.
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What are FRs?
Sorry for not being clear, but I meant feature requests. I thought some operations could use GeneratorExp and there might not be a reason to limit my function only to summation.
However, your point on bare visitors makes sense.
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This function can be reused with other operators (e.g., products and integrals have the same syntax). We can use some general action name rather than sum.
set_bounds as suggested in the new commit?
latexify/core.py
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| @@ -224,6 +244,27 @@ def visit_If(self, node, action): # pylint: disable=invalid-name | |||
| latex += self.visit(node) | |||
| return latex + r', & \mathrm{otherwise} \end{array} \right.' | |||
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| def visit_GeneratorExp_sum(self, node): # pylint: disable=invalid-name | |||
There was a problem hiding this comment.
What are FRs?
This function can be reused with other operators (e.g., products and integrals have the same syntax). We can use some general action name rather than sum.
latexify/core.py
Outdated
| @@ -224,6 +244,27 @@ def visit_If(self, node, action): # pylint: disable=invalid-name | |||
| latex += self.visit(node) | |||
| return latex + r', & \mathrm{otherwise} \end{array} \right.' | |||
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| def visit_GeneratorExp_sum(self, node): # pylint: disable=invalid-name | |||
There was a problem hiding this comment.
I think the bare visitor (=visitor with None action) of every node should return only a LaTeX string. Otherwise every parent node is required to know what kind of objects are returned from children and how to process them to construct LaTeX strings.
…ts (or bounds) - Use n - 1 instead of n in test (the second arg in range is exclusive) - Use more general name to support limits operation (sum is not the only operation that could use limits but integral of products are, too)
| from typing import NamedTuple | ||
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| class Actions(NamedTuple): |
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I decided to use NamedTuple here because of two benefits.
- It allows dot access - e.g.
constants.actions.SET_BOUNDS(vs.constants.actions[key]with adictimplementation) - Tuples are immutable.
NamedTuplecan be written more simpler than a class.
I could have prepared another file actions.py to achieve the same interface, but actions are essentially constants. Thus I preferred to keep it in constants.py.
If you think otherwise, please let me know.
This supports summation with limits (super/subscripts) written with comprehension with for loop and range function.
Example usage is outlined in
tests/test_io.pyNote:
y_bar[i]).sum_with_limitandtest_with_latex_to_strintests/test_io.pyare impacted by issue Underscores in function names conflict with LaTeX and shown as subscripts #31 , which need to be corrected after its fix.