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MeanFourier
.
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.
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Imports
Init
MeanFourier.InvtMean
Mathlib.Combinatorics.Additive.CovBySMul
Imported by
InvtMean
.
l2AP
InvtMean
.
«termAP_L^2(_)(_,_)»
InvtMean
.
mem_l2AP
InvtMean
.
mem_l2AP_indicator_one
InvtMean
.
IsL2APWith
L^2(m)
#
source
def
InvtMean
.
l2AP
{
G
:
Type
u_1}
[
Group
G
]
(
m
:
InvtMean
G
)
(
f
:
G
→
ℂ
)
(
ε
:
ℝ
)
:
Set
G
Equations
AP_L^2(
m
)(
f
,
ε
)
=
{
t
:
G
|
m
.
l2Norm
(
(fun (
g
:
G
) =>
f
(
t
⁻¹
*
g
)
)
-
f
)
≤
ε
*
m
.
l2Norm
f
}
Instances For
source
def
InvtMean
.
«termAP_L^2(_)(_,_)»
:
Lean.ParserDescr
Equations
One or more equations did not get rendered due to their size.
Instances For
source
@[simp]
theorem
InvtMean
.
mem_l2AP
{
G
:
Type
u_1}
[
Group
G
]
{
m
:
InvtMean
G
}
{
f
:
G
→
ℂ
}
{
t
:
G
}
{
ε
:
ℝ
}
:
t
∈
AP_L^2(
m
)(
f
,
ε
)
↔
m
.
l2Norm
(
(fun (
g
:
G
) =>
f
(
t
⁻¹
*
g
)
)
-
f
)
≤
ε
*
m
.
l2Norm
f
source
@[simp]
theorem
InvtMean
.
mem_l2AP_indicator_one
{
G
:
Type
u_1}
[
Group
G
]
{
m
:
InvtMean
G
}
{
A
:
Set
G
}
{
t
:
G
}
{
ε
:
ℝ
}
:
t
∈
AP_L^2(
m
)(
A
.
indicator
fun (
x
:
G
) =>
1
,
ε
)
↔
m
.
real
(
(
(
t
•
A
).
indicator
fun (
x
:
G
) =>
1
)
-
A
.
indicator
fun (
x
:
G
) =>
1
)
≤
ε
^
2
*
m
.
real
(
A
.
indicator
fun (
x
:
G
) =>
1
)
source
def
InvtMean
.
IsL2APWith
{
G
:
Type
u_1}
[
Group
G
]
(
m
:
InvtMean
G
)
(
f
:
G
→
ℂ
)
(
K
:
ℝ
→
ℝ
)
:
Prop
Equations
m
.
IsL2APWith
f
K
=
∀
ε
>
0
,
CovBySMul
G
(
K
ε
)
Set.univ
AP_L^2(
m
)(
f
,
ε
)
Instances For