logo

Expression of type Lambda

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, Lambda, a, c
from proveit.logic import And
from proveit.numbers import Abs, Less, Neg
In [2]:
# build up the expression from sub-expressions
expr = Lambda([a, c], Conditional(Less(Abs(a), c), And(Less(Neg(c), a), Less(a, c)).with_total_ordering_style()))
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(a, c\right) \mapsto \left\{\left|a\right| < c \textrm{ if } \left(-c\right) < a ,  a < c\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameters: 14
body: 1
1Conditionalvalue: 2
condition: 3
2Operationoperator: 13
operands: 4
3Operationoperator: 5
operands: 6
4ExprTuple7, 19
5Literal
6ExprTuple8, 9
7Operationoperator: 10
operand: 16
8Operationoperator: 13
operands: 12
9Operationoperator: 13
operands: 14
10Literal
11ExprTuple16
12ExprTuple15, 16
13Literal
14ExprTuple16, 19
15Operationoperator: 17
operand: 19
16Variable
17Literal
18ExprTuple19
19Variable