# Create ellipticity residuals quiver plots

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#### Details

• Type: Story
• Status: Done
• Resolution: Done
• Fix Version/s: None
• Component/s:
• Labels:
None
• Story Points:
5
• Sprint:
DRP S17-2, DRP S17-3, DRP S17-4, DRP S17-5, DRP S17-6
• Team:
Data Release Production

#### Description

Include ellipticity residual comparison and quiver plots in the analysis script, including:

Intra-stack:
scatter/histogram/sky plots for psfUsed stars of
> residual e1 & e2 ellipticities between the source and model psf at the position of the source (for both SDSS and HSM measurements), where:

 e1 = (shape_xx - shape_yy)/(shape_xx + shape_yy) e2 = 2*shape_xy/(shape_xx + shape_yy) 

> residual ellipticity, δe, between source and model psf at source position quiver plot where:

 δe = sqrt((e1_src - e1_psf)^2 + (e2_src - e2_psf)^2)) 

Inter-stack:
scatter/histogram/sky comparison plots for;
> comparison of the trace radii of the sf models at the position of psfUsed stars matched between the two stack catalogs, where:

 traceRadius = sqrt(0.5*(shape_xx + shape_yy)) 

#### Activity

Hide
Lauren MacArthur added a comment -

This latter plot that revealed a systematic 0.5% difference between the model psf trace radii
between the HSC-1382 RC dataset run and the LSST run of DM-6816 (I do realize I will have to fix the binning in the right histogram!):

Show
Lauren MacArthur added a comment - This latter plot that revealed a systematic 0.5% difference between the model psf trace radii between the HSC-1382 RC dataset run and the LSST run of DM-6816 (I do realize I will have to fix the binning in the right histogram!):
Hide
Lauren MacArthur added a comment -

The following show the plots for a visit level (processCcd + meas_mosaic) run:

and for a tract in the COSMOS HSC RC dataset:

Show
Lauren MacArthur added a comment - The following show the plots for a visit level (processCcd + meas_mosaic) run: and for a tract in the COSMOS HSC RC dataset:
Hide
Lauren MacArthur added a comment -

 def getQuiver(x, y, e1, e2, ax, color=None, scale=3, width=0.005, label=''):  """Return the quiver object for the given input parameters"""  theta = [np.math.atan2(a, b)/2.0 for a, b in zip(e1, e2)]  e = np.sqrt(e1**2 +e2**2)  c1 = e*np.cos(theta)  c2 = e*np.sin(theta)  if color is None:  color = e  q = ax.quiver(x, y, c1, c2, color=color, angles='uv', scale=scale,  units='width', pivot='middle', width=width, headwidth=0.0,  headlength=0.0, headaxislength=0.0, label=label)    return q 

But for the above plots I used scale=2 and width=0,002.

Show
Lauren MacArthur added a comment - The function added looks like: def getQuiver(x, y, e1, e2, ax, color=None, scale=3, width=0.005, label=''): """Return the quiver object for the given input parameters""" theta = [np.math.atan2(a, b)/2.0 for a, b in zip(e1, e2)] e = np.sqrt(e1**2 +e2**2) c1 = e*np.cos(theta) c2 = e*np.sin(theta) if color is None: color = e q = ax.quiver(x, y, c1, c2, color=color, angles='uv', scale=scale, units='width', pivot='middle', width=width, headwidth=0.0, headlength=0.0, headaxislength=0.0, label=label)   return q But for the above plots I used scale=2 and width=0,002 .
Hide
Lauren MacArthur added a comment -

Bob Armstrong, would you mind giving these plots a quick glance to ensure they look right? There's no need to review any code, but you can have a look if you'd like on the u/lauren/working branch in pipe_analysis on lsst-dm github.

Show
Lauren MacArthur added a comment - Bob Armstrong , would you mind giving these plots a quick glance to ensure they look right? There's no need to review any code, but you can have a look if you'd like on the u/lauren/working branch in pipe_analysis on lsst-dm github.
Hide
John Swinbank added a comment -

Bob Armstrong, Lauren MacArthur — this has been "in review" for a couple of months now. Any chance we can close it out? I'd love to shut it down for the end of the S17 cycle.

Show
John Swinbank added a comment - Bob Armstrong , Lauren MacArthur — this has been "in review" for a couple of months now. Any chance we can close it out? I'd love to shut it down for the end of the S17 cycle.

#### People

Assignee:
Lauren MacArthur
Reporter:
Lauren MacArthur
Reviewers:
Bob Armstrong
Watchers:
Bob Armstrong, John Swinbank, Lauren MacArthur