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Expression of type ExprTuple

from the theory of proveit.numbers.absolute_value

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, ExprTuple, Lambda, x, y
from proveit.logic import And, Iff, InSet
from proveit.numbers import Abs, LessEq, Neg, Real, greater_eq, zero
In [2]:
# build up the expression from sub-expressions
expr = ExprTuple(Lambda([x, y], Conditional(Iff(LessEq(Abs(x), y), And(LessEq(Neg(y), x), LessEq(x, y))), And(InSet(x, Real), InSet(y, Real), greater_eq(y, zero)))))
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(x, y\right) \mapsto \left\{\left(\left|x\right| \leq y\right) \Leftrightarrow \left(\left(\left(-y\right) \leq x\right) \land \left(x \leq y\right)\right) \textrm{ if } x \in \mathbb{R} ,  y \in \mathbb{R} ,  y \geq 0\right..\right)
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0ExprTuple1
1Lambdaparameters: 29
body: 2
2Conditionalvalue: 3
condition: 4
3Operationoperator: 5
operands: 6
4Operationoperator: 14
operands: 7
5Literal
6ExprTuple8, 9
7ExprTuple10, 11, 12
8Operationoperator: 28
operands: 13
9Operationoperator: 14
operands: 15
10Operationoperator: 17
operands: 16
11Operationoperator: 17
operands: 18
12Operationoperator: 28
operands: 19
13ExprTuple20, 34
14Literal
15ExprTuple21, 22
16ExprTuple31, 23
17Literal
18ExprTuple34, 23
19ExprTuple24, 34
20Operationoperator: 25
operand: 31
21Operationoperator: 28
operands: 27
22Operationoperator: 28
operands: 29
23Literal
24Literal
25Literal
26ExprTuple31
27ExprTuple30, 31
28Literal
29ExprTuple31, 34
30Operationoperator: 32
operand: 34
31Variable
32Literal
33ExprTuple34
34Variable