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Expression of type Lambda

from the theory of proveit.linear_algebra.linear_maps

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, Function, Lambda, P, Px, Py, V, x, y
from proveit.linear_algebra import VecAdd
from proveit.logic import And, Equals, InSet
In [2]:
# build up the expression from sub-expressions
expr = Lambda([x, y], Conditional(Equals(Function(P, [VecAdd(x, y)]), VecAdd(Px, Py)), And(InSet(x, V), InSet(y, V))))
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(x, y\right) \mapsto \left\{P\left(x + y\right) = \left(P\left(x\right) + P\left(y\right)\right) \textrm{ if } x \in V ,  y \in V\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameters: 22
body: 1
1Conditionalvalue: 2
condition: 3
2Operationoperator: 4
operands: 5
3Operationoperator: 6
operands: 7
4Literal
5ExprTuple8, 9
6Literal
7ExprTuple10, 11
8Operationoperator: 24
operand: 17
9Operationoperator: 21
operands: 13
10Operationoperator: 15
operands: 14
11Operationoperator: 15
operands: 16
12ExprTuple17
13ExprTuple18, 19
14ExprTuple26, 20
15Literal
16ExprTuple27, 20
17Operationoperator: 21
operands: 22
18Operationoperator: 24
operand: 26
19Operationoperator: 24
operand: 27
20Variable
21Literal
22ExprTuple26, 27
23ExprTuple26
24Variable
25ExprTuple27
26Variable
27Variable