Skip to content

Commit 52c6c06

Browse files
authored
Merge pull request #29 from asgr/copilot/improve-documentation-clarity
Update vignettes to replace deprecated `profoundMakeStack` with ProPane's `propaneStackFlatInVar`
2 parents 79d30e1 + 5f800b1 commit 52c6c06

2 files changed

Lines changed: 3 additions & 3 deletions

File tree

vignettes/ProFound-Source-Finding.Rmd

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -34,7 +34,7 @@ The **ProFound** source finding and image utilities suite covers the following f
3434
- profoundMakeSegimPropagate: Propagate segmentation map segments over adjacent sky pixels
3535
- profoundMakeSigma: Make a Sigma Map
3636
- profoundMakeSkyMap: Calculate coarse sky maps
37-
- profoundMakeStack: Create a stacked image
37+
- propaneStackFlatInVar (ProPane): Create an inverse-variance weighted stacked image
3838
- profoundPixelCorrelation: Calculate pixel-to-pixel correlation and 2D image FFT
3939
- profoundSegimGroup: Find the IDs of groups of touching segments
4040
- profoundSegimMerge: Optimally merge segmentation maps

vignettes/ProFound-Stack-Images.Rmd

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -37,9 +37,9 @@ If you have many images of the same area (even in different bands) a photometric
3737

3838
To convince yourself consider you have 8 exposures with sky RMS equal to 16 originally: 4 you combine, so the sky RMS becomes $\frac{1}{\sqrt{\frac{1}{16^2}+\frac{1}{16^2}+\frac{1}{16^2}+\frac{1}{16^2}}}=\frac{1}{\sqrt{\frac{4}{16^2}}}=8$. Now later on you want to combine the 5 images you have. Clearly the optimal weighting you can possibly get will be $\frac{1}{\sqrt{\frac{8}{16^2}}}=\frac{8}{\sqrt{2}}=5.65$ (the direct stack of the original 8 images). With our already stacked image added to our 4 others we can achieve the same S/N by weighting our stacks by the inverse variance: $\frac{1}{\sqrt{\frac{1}{16^2}+\frac{1}{16^2}+\frac{1}{16^2}+\frac{1}{16^2}+\frac{1}{8^2}}}=\frac{1}{\sqrt{\frac{4}{16^2}+\frac{1}{8^2}}}=\frac{1}{\sqrt{\frac{8}{16^2}}}=\frac{8}{\sqrt{2}}=5.65$.
3939

40-
**ProFound** comes with a handy function that does all the weight-watching for us called **profoundMakeStack**. In this vignette we will make a simulated image (with a trivially predictable improvement in S/N) and check to see that our stacking behaves as expected.
40+
**ProPane** comes with a handy function that does all the weight-watching for us called **propaneStackFlatInVar**. In this vignette we will make a simulated image (with a trivially predictable improvement in S/N) and check to see that our stacking behaves as expected.
4141

42-
First we generate a random image with 200 stars and 200 extended sources. The value used roughly correspoond to the source densities and magnitude distributions you might expect to find in a Z-band VIKING frame (this was used to derive the image statistics).
42+
First we generate a random image with 200 stars and 200 extended sources. The value used roughly correspond to the source densities and magnitude distributions you might expect to find in a Z-band VIKING frame (this was used to derive the image statistics).
4343

4444
```{r, eval=evalglobal}
4545
set.seed(666)

0 commit comments

Comments
 (0)