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Expression of type Conditional

from the theory of proveit.linear_algebra.vector_sets

In [1]:
import proveit
# Automation is not needed when building an expression:
proveit.defaults.automation = False # This will speed things up.
proveit.defaults.inline_pngs = False # Makes files smaller.
%load_expr # Load the stored expression as 'stored_expr'
# import Expression classes needed to build the expression
from proveit import Conditional, ExprRange, IndexedVar, V, Variable, n, x
from proveit.core_expr_types import x_1_to_n
from proveit.linear_algebra import Span, SpanningSets
from proveit.logic import And, Equals, InSet, Set
from proveit.numbers import one
In [2]:
# build up the expression from sub-expressions
sub_expr1 = Variable("_a", latex_format = r"{_{-}a}")
sub_expr2 = Set(x_1_to_n)
expr = Conditional(Equals(InSet(sub_expr2, SpanningSets(V)), Equals(V, Span(sub_expr2))), And(ExprRange(sub_expr1, InSet(IndexedVar(x, sub_expr1), V), one, n)))
expr:
In [3]:
# check that the built expression is the same as the stored expression
assert expr == stored_expr
assert expr._style_id == stored_expr._style_id
print("Passed sanity check: expr matches stored_expr")
Passed sanity check: expr matches stored_expr
In [4]:
# Show the LaTeX representation of the expression for convenience if you need it.
print(stored_expr.latex())
\left\{\left(\left\{x_{1}, x_{2}, \ldots, x_{n}\right\} \in \textrm{SpanningSets}\left(V\right)\right) = \left(V = \textrm{Span}\left(\left\{x_{1}, x_{2}, \ldots, x_{n}\right\}\right)\right) \textrm{ if } \left(x_{1} \in V\right) \land  \left(x_{2} \in V\right) \land  \ldots \land  \left(x_{n} \in V\right)\right..
In [5]:
stored_expr.style_options()
namedescriptiondefaultcurrent valuerelated methods
condition_delimiter'comma' or 'and'commacomma('with_comma_delimiter', 'with_conjunction_delimiter')
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Conditionalvalue: 1
condition: 2
1Operationoperator: 10
operands: 3
2Operationoperator: 4
operands: 5
3ExprTuple6, 7
4Literal
5ExprTuple8
6Operationoperator: 20
operands: 9
7Operationoperator: 10
operands: 11
8ExprRangelambda_map: 12
start_index: 28
end_index: 29
9ExprTuple22, 13
10Literal
11ExprTuple23, 14
12Lambdaparameter: 33
body: 15
13Operationoperator: 16
operand: 23
14Operationoperator: 18
operand: 22
15Operationoperator: 20
operands: 21
16Literal
17ExprTuple23
18Literal
19ExprTuple22
20Literal
21ExprTuple30, 23
22Operationoperator: 24
operands: 25
23Variable
24Literal
25ExprTuple26
26ExprRangelambda_map: 27
start_index: 28
end_index: 29
27Lambdaparameter: 33
body: 30
28Literal
29Variable
30IndexedVarvariable: 31
index: 33
31Variable
32ExprTuple33
33Variable