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Expression of type Lambda

from the theory of proveit.linear_algebra.matrices

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 A, Lambda, b, k, x
from proveit.linear_algebra import MatrixMult, ScalarMult
from proveit.logic import Equals, Implies
from proveit.numbers import Exp
In [2]:
# build up the expression from sub-expressions
expr = Lambda([A, x], Implies(Equals(MatrixMult(A, x), ScalarMult(b, x)), Equals(MatrixMult(Exp(A, k), x), ScalarMult(Exp(b, k), x))))
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, x\right) \mapsto \left(\left(\left(A \thinspace x\right) = \left(b \cdot x\right)\right) \Rightarrow \left(\left(A^{k} \thinspace x\right) = \left(b^{k} \cdot x\right)\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
1Operationoperator: 2
operands: 3
2Literal
3ExprTuple4, 5
4Operationoperator: 7
operands: 6
5Operationoperator: 7
operands: 8
6ExprTuple9, 10
7Literal
8ExprTuple11, 12
9Operationoperator: 15
operands: 13
10Operationoperator: 17
operands: 14
11Operationoperator: 15
operands: 16
12Operationoperator: 17
operands: 18
13ExprTuple25, 21
14ExprTuple26, 21
15Literal
16ExprTuple19, 21
17Literal
18ExprTuple20, 21
19Operationoperator: 23
operands: 22
20Operationoperator: 23
operands: 24
21Variable
22ExprTuple25, 27
23Literal
24ExprTuple26, 27
25Variable
26Variable
27Variable