Convolution Notation: The difference between (f*g)(x) and f(x)*g(x)
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What is the difference between (f*g)(x) and f(x)*g(x) [1] for convolutions? Are they the same? I ask this because I have been asked to prove the Reflection of Convolution property for my course in the Theory of Distributions,
i.e that f(-x)g(-x)=(fg)(-x). But if there is no difference between [1], then surely the proof follows from [1] and nothing actually needs to be proven.
notation convolution reflection
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What is the difference between (f*g)(x) and f(x)*g(x) [1] for convolutions? Are they the same? I ask this because I have been asked to prove the Reflection of Convolution property for my course in the Theory of Distributions,
i.e that f(-x)g(-x)=(fg)(-x). But if there is no difference between [1], then surely the proof follows from [1] and nothing actually needs to be proven.
notation convolution reflection
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up vote
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down vote
favorite
What is the difference between (f*g)(x) and f(x)*g(x) [1] for convolutions? Are they the same? I ask this because I have been asked to prove the Reflection of Convolution property for my course in the Theory of Distributions,
i.e that f(-x)g(-x)=(fg)(-x). But if there is no difference between [1], then surely the proof follows from [1] and nothing actually needs to be proven.
notation convolution reflection
New contributor
What is the difference between (f*g)(x) and f(x)*g(x) [1] for convolutions? Are they the same? I ask this because I have been asked to prove the Reflection of Convolution property for my course in the Theory of Distributions,
i.e that f(-x)g(-x)=(fg)(-x). But if there is no difference between [1], then surely the proof follows from [1] and nothing actually needs to be proven.
notation convolution reflection
notation convolution reflection
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$f*g$ means that $*$ is defined on the space of functions. The notation $f(x)*g(x)$ makes it look as though $*$ is defined on the space of real numbers (if the functions are real that is), and hence isn't great. It's the same solecism as talking about 'the function $f(x)$'---it's $f$ that is the function, not $f(x)$.
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1 Answer
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active
oldest
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active
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active
oldest
votes
up vote
2
down vote
$f*g$ means that $*$ is defined on the space of functions. The notation $f(x)*g(x)$ makes it look as though $*$ is defined on the space of real numbers (if the functions are real that is), and hence isn't great. It's the same solecism as talking about 'the function $f(x)$'---it's $f$ that is the function, not $f(x)$.
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up vote
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$f*g$ means that $*$ is defined on the space of functions. The notation $f(x)*g(x)$ makes it look as though $*$ is defined on the space of real numbers (if the functions are real that is), and hence isn't great. It's the same solecism as talking about 'the function $f(x)$'---it's $f$ that is the function, not $f(x)$.
add a comment |
up vote
2
down vote
up vote
2
down vote
$f*g$ means that $*$ is defined on the space of functions. The notation $f(x)*g(x)$ makes it look as though $*$ is defined on the space of real numbers (if the functions are real that is), and hence isn't great. It's the same solecism as talking about 'the function $f(x)$'---it's $f$ that is the function, not $f(x)$.
$f*g$ means that $*$ is defined on the space of functions. The notation $f(x)*g(x)$ makes it look as though $*$ is defined on the space of real numbers (if the functions are real that is), and hence isn't great. It's the same solecism as talking about 'the function $f(x)$'---it's $f$ that is the function, not $f(x)$.
answered yesterday
Richard Martin
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