Skip to main content
Bumped by Community user
Bumped by Community user
Bumped by Community user
Bumped by Community user
Notice removed Draw attention by CommunityBot
Bounty Ended with no winning answer by CommunityBot
added 397 characters in body
Source Link
dff
  • 230
  • 1
  • 14

Let $f(x)$ be some unknown continuous square-integrable function defined on the interval [0,1]$[0,1]$.

Suppose we have $i=1,...,n$ samples $f_i$ of $f$ of the following form: $$f_i(x)=a_i*f(x+b_i)+c_i$$ where each sample is defined on the interval $[\alpha,1-\alpha]$ and $-\alpha \leq b_i \leq \alpha$ for $0\leq\alpha<1/2$.

Additionally, assume that for at least two of the samples, $b_i$ equals $-\alpha$ and $\alpha$ respectively, i.e. the whole domain of $f(x)$ is sampled. Furthermore, assume $\int_0^1 f(x)\mathrm{d}x=0$ and $\int_0^1 (f (x))^2\mathrm{d}x=1$. Finally, since the sign of $f(x)$ is not retrievable, we care only about retrieving either $f(x)$ or $-f(x)$.

What would be an efficient way to estimatedetermine $f(x)$, $a_i$, $b_i$ and $c_i$? For $\alpha=b_i=0$, a PCA-like analysis would work, but how to treat the case $0<\alpha<1/2$?

Let $f(x)$ be some unknown continuous function defined on the interval [0,1].

Suppose we have $i=1,...,n$ samples $f_i$ of $f$ of the following form: $$f_i(x)=a_i*f(x+b_i)+c_i$$ where each sample is defined on the interval $[\alpha,1-\alpha]$ and $-\alpha \leq b_i \leq \alpha$.

What would be an efficient way to estimate $f(x)$, $a_i$, $b_i$ and $c_i$? For $\alpha=b_i=0$, a PCA-like analysis would work, but how to treat the case $0<\alpha<1/2$?

Let $f(x)$ be some unknown continuous square-integrable function defined on the interval $[0,1]$.

Suppose we have $i=1,...,n$ samples $f_i$ of $f$ of the following form: $$f_i(x)=a_i*f(x+b_i)+c_i$$ where each sample is defined on the interval $[\alpha,1-\alpha]$ and $-\alpha \leq b_i \leq \alpha$ for $0\leq\alpha<1/2$.

Additionally, assume that for at least two of the samples, $b_i$ equals $-\alpha$ and $\alpha$ respectively, i.e. the whole domain of $f(x)$ is sampled. Furthermore, assume $\int_0^1 f(x)\mathrm{d}x=0$ and $\int_0^1 (f (x))^2\mathrm{d}x=1$. Finally, since the sign of $f(x)$ is not retrievable, we care only about retrieving either $f(x)$ or $-f(x)$.

What would be an efficient way to determine $f(x)$, $a_i$, $b_i$ and $c_i$? For $\alpha=b_i=0$, a PCA-like analysis would work, but how to treat the case $0<\alpha<1/2$?

Notice added Draw attention by dff
Bounty Started worth 200 reputation by dff
Source Link
dff
  • 230
  • 1
  • 14

Shape, shift and scaling retrieval of a sampled function

Let $f(x)$ be some unknown continuous function defined on the interval [0,1].

Suppose we have $i=1,...,n$ samples $f_i$ of $f$ of the following form: $$f_i(x)=a_i*f(x+b_i)+c_i$$ where each sample is defined on the interval $[\alpha,1-\alpha]$ and $-\alpha \leq b_i \leq \alpha$.

What would be an efficient way to estimate $f(x)$, $a_i$, $b_i$ and $c_i$? For $\alpha=b_i=0$, a PCA-like analysis would work, but how to treat the case $0<\alpha<1/2$?