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Use correct symbols

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The unicode symbols are some strange script, they look similar but are not the actual symbols for
math operations. They are leftovers from version 1. The actual values were fixed but not the comments.
This commit is contained in:
Salvo 'LtWorf' Tomaselli 2020-06-09 12:32:09 +02:00
parent 72c4746578
commit 6208333f48
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GPG Key ID: B3A7CF0C801886CF
1 changed files with 8 additions and 8 deletions
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16
relational/optimizations.py
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@ -126,14 +126,14 @@ def duplicated_select(n: parser.Node) -> Tuple[parser.Node, int]:
def futile_union_intersection_subtraction(n: parser.Node) -> Tuple[parser.Node, int]:
'''This function locates things like r ᑌ r, and replaces them with r.
R ᑌ R --> R
R ᑎ R --> R
'''This function locates things like r ∪ r, and replaces them with r.
R ∪ R --> R
R ∩ R --> R
R - R --> σ False (R)
σ k (R) - R --> σ False (R)
R - σ k (R) --> σ not k (R)
σ k (R) ᑌ R --> R
σ k (R) ᑎ R --> σ k (R)
σ k (R) ∪ R --> R
σ k (R) ∩ R --> σ k (R)
'''
changes = 0
@ -176,9 +176,9 @@ def futile_union_intersection_subtraction(n: parser.Node) -> Tuple[parser.Node,
def down_to_unions_subtractions_intersections(n: parser.Node) -> Tuple[parser.Node, int]:
'''This funcion locates things like σ i==2 (c ᑌ d), where the union
'''This funcion locates things like σ i==2 (c ∪ d), where the union
can be a subtraction and an intersection and replaces them with
σ i==2 (c) ᑌ σ i==2(d).
σ i==2 (c) ∪ σ i==2(d).
'''
changes = 0
_o = (UNION, DIFFERENCE, INTERSECTION)
@ -440,7 +440,7 @@ def swap_rename_select(n: parser.Node) -> int:
def select_union_intersect_subtract(n: parser.Node) -> int:
'''This function locates things like σ i(a) ᑌ σ q(a)
'''This function locates things like σ i(a) ∪ σ q(a)
and replaces them with σ (i OR q) (a)
Removing a O(n²) operation like the union'''
changes = 0