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Expression of type Lambda

from the theory of proveit.linear_algebra.inner_products

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, H, K, Lambda, alpha, x
from proveit.linear_algebra import Norm, ScalarMult
from proveit.logic import And, Equals, InSet
from proveit.numbers import Abs, Mult
In [2]:
# build up the expression from sub-expressions
expr = Lambda([alpha, x], Conditional(Equals(Norm(ScalarMult(alpha, x)), Mult(Abs(alpha), Norm(x))), And(InSet(alpha, K), InSet(x, H))))
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(\alpha, x\right) \mapsto \left\{\left \|\alpha \cdot x\right \| = \left(\left|\alpha\right| \cdot \left \|x\right \|\right) \textrm{ if } \alpha \in K ,  x \in H\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameters: 24
body: 1
1Conditionalvalue: 2
condition: 3
2Operationoperator: 4
operands: 5
3Operationoperator: 6
operands: 7
4Literal
5ExprTuple8, 9
6Literal
7ExprTuple10, 11
8Operationoperator: 27
operand: 18
9Operationoperator: 13
operands: 14
10Operationoperator: 16
operands: 15
11Operationoperator: 16
operands: 17
12ExprTuple18
13Literal
14ExprTuple19, 20
15ExprTuple29, 21
16Literal
17ExprTuple30, 22
18Operationoperator: 23
operands: 24
19Operationoperator: 25
operand: 29
20Operationoperator: 27
operand: 30
21Variable
22Variable
23Literal
24ExprTuple29, 30
25Literal
26ExprTuple29
27Literal
28ExprTuple30
29Variable
30Variable