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Expression of type Lambda

from the theory of proveit.core_expr_types.tuples

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 ExprRange, Function, IndexedVar, Lambda, Variable, f, i, j
In [2]:
# build up the expression from sub-expressions
sub_expr1 = Variable("_b", latex_format = r"{_{-}b}")
sub_expr2 = Variable("_a", latex_format = r"{_{-}a}")
expr = Lambda(sub_expr1, ExprRange(sub_expr2, Function(IndexedVar(f, sub_expr1), [sub_expr2]), i, j))
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())
{_{-}b} \mapsto f_{{_{-}b}}\left(i\right), f_{{_{-}b}}\left(i + 1\right), \ldots, f_{{_{-}b}}\left(j\right)
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameter: 11
body: 1
1ExprRangelambda_map: 2
start_index: 3
end_index: 4
2Lambdaparameter: 10
body: 5
3Variable
4Variable
5Operationoperator: 6
operand: 10
6IndexedVarvariable: 8
index: 11
7ExprTuple10
8Variable
9ExprTuple11
10Variable
11Variable