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Expression of type Lambda

from the theory of proveit.linear_algebra.addition

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, Lambda, Variable, a, i
from proveit.core_expr_types import a_1_to_i
from proveit.linear_algebra import VecAdd
from proveit.logic import And, Equals, InSet
from proveit.numbers import Add, Complex, one
In [2]:
# build up the expression from sub-expressions
sub_expr1 = Variable("_a", latex_format = r"{_{-}a}")
expr = Lambda([a_1_to_i], Conditional(Equals(VecAdd(a_1_to_i), Add(a_1_to_i)), And(ExprRange(sub_expr1, InSet(IndexedVar(a, sub_expr1), Complex), one, i))))
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_{1}, a_{2}, \ldots, a_{i}\right) \mapsto \left\{\left(a_{1} +  a_{2} +  \ldots +  a_{i}\right) = \left(a_{1} +  a_{2} +  \ldots +  a_{i}\right) \textrm{ if } \left(a_{1} \in \mathbb{C}\right) \land  \left(a_{2} \in \mathbb{C}\right) \land  \ldots \land  \left(a_{i} \in \mathbb{C}\right)\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameters: 13
body: 1
1Conditionalvalue: 2
condition: 3
2Operationoperator: 4
operands: 5
3Operationoperator: 6
operands: 7
4Literal
5ExprTuple8, 9
6Literal
7ExprTuple10
8Operationoperator: 11
operands: 13
9Operationoperator: 12
operands: 13
10ExprRangelambda_map: 14
start_index: 18
end_index: 19
11Literal
12Literal
13ExprTuple15
14Lambdaparameter: 26
body: 16
15ExprRangelambda_map: 17
start_index: 18
end_index: 19
16Operationoperator: 20
operands: 21
17Lambdaparameter: 26
body: 22
18Literal
19Variable
20Literal
21ExprTuple22, 23
22IndexedVarvariable: 24
index: 26
23Literal
24Variable
25ExprTuple26
26Variable