Differences between revisions 2 and 26 (spanning 24 versions)

RESIDUALS.TXT

Compiled by KD

Description

RESIDUALS.TXT is a report created by residuals that looks for bad landmarks.

A basic description of the information in RESIDUALS.TXT.

The post-fit residuals between predicted and actual control point positions in all images are captured in the residuals file
The post-fit residuals between predicted and actual control point difference between adjacent, overlapping maplets are captured in the residuals file
Outliers in both quantities are flagged automatically based on input threshold criteria

A more in depth list explaining the information in the RESIDUALS.TXT file is shown below.

In between the dot rows:
- The name of a landmark
- T (landmark has a map with it) or F (flat landmark, no image)
- Resolution
- Lat of landmark
- Wlon of landmark
- Radius
Below the dot rows with the landmark name above them:
- For each image:
  - 1st column - picture name
  - 2nd column - PX residual (# of pixels in image resolution)
  - 3rd column - LN residual (# of pixels in image resolution)
  - 4th column - magnitude of PX and LN residuals (# of pixels in image resolution)
  - 5th column - the estimate linear residual (km)
- For each overlap:
  - 1st column - overlap name
  - 2nd column - X residual (km)
  - 3rd column - Y residual (km)
  - 4rd column - Z residual (km)
  - 5th column - estimate linear residual (km)
- For each limb apperation:
  - 1st column - picture name
  - 2nd column - PX residual (# of pixels in image resolution)
  - 3rd column - LN residual (# of pixels in image resolution)
  - 4th column - magnitude of PX and LN residuals (# of pixels in image resolution)
  - 5th column - the estimate linear residual (km)
Below the images, overlaps, and limbs list for a landmark:
- Landmark name
- magnitude of RMS linear residual for landmark
Below the single dot row at the very bottom of the image:
- Observations - how many IMAGEFILES, overlaps, and limbs for all landmarks
- RMS RESIDUAL - overall RMS linear residual in meters.

The user should note that residuals are the difference between observed landmark positions and those predicted by the solution (SPC).

Observed landmark positions are exactly as the name suggests, positions of a landmark calculated by the code when it inputs pictures from the spacecraft of the object.

Predicted landmark positions are those calculated by SPC when it inputs it generates a solution (map) from all the pictures collected.

During iteration and refinement of the SPC solution, the position and attitude of the spacecraft are slightly changed over and over until the the maps match the images as best they can. At then end of each iteration SUMFILES are then updated for the new attitude and position.

Thus, when the RMS between landmark residuals is as low as possible the maps match the images well, which means the updated SUMFILE is the new estimate for space craft position and attitude.

Example of a RESIDUALS.TXT File

..................................................
IA1_01 T      0.0200     56.5481    140.8124     13.6146
..................................................
    A1_01                 8.139    -6.853    10.640   0.01091
    A2_05               -28.427    49.215    56.835   0.04250
    B1_01                -3.517    52.347    52.465   0.04857
    B1_03               -18.475   -57.091    60.006   0.05509
IA1_01     42.78

..................................................
IA1_03 T      0.0200     36.4771    136.8269     11.4593
..................................................
    A1_03               -29.498   -12.161    31.906   0.04002
    A2_03               -71.840    23.961    75.731   0.07142
    A2_04                -3.885    -4.689     6.089   0.00643
    A2_05               -34.754    95.249   101.392   0.10527
    B1_01                64.895   -21.470    68.354   0.07337
    B1_03                11.000    59.329    60.340   0.06832
    B2_04                97.637    29.005   101.855   0.11002
    B2_05                42.109    41.562    59.165   0.07455
IA1_03     75.45


.........

 Observation # =       360180

 RMS Residual (m) =   0.78928860594347106

-  ⇤ ← Revision 2 as of 2013-02-04 15:57:57 → 
  Size: 1677
  Editor: ROBERT W GASKELL
  Comment:
+   ← Revision 26 as of 2016-01-27 10:01:06 → ⇥
  Size: 4320
  Editor: KristoferDrozd
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 3:
+Compiled by KD
-Line 4:
+Line 5:
+== Description ==
-Line 5:
+Line 7:
- * The name of a landmark
 * The error for each image.  
 No huge numbers of NaN
+RESIDUALS.TXT is a report created by [[residuals]] that looks for bad landmarks.
 Line 9:
-  T has a map with it
  F flat landmark, no image
 landmark, resolution, lat, lon, radius
+A basic description of the information in RESIDUALS.TXT.

 * The post-fit residuals between predicted and actual control point positions in all images are captured in the residuals file
 * The post-fit residuals between predicted and actual control point difference between adjacent, overlapping maplets are captured in the residuals file
 * Outliers in both quantities are flagged automatically based on input threshold criteria 

A more in depth list explaining the information in the RESIDUALS.TXT file is shown below.

 * In between the dot rows:
  * The name of a landmark
  * T (landmark has a map with it) or F (flat landmark, no image)
  * Resolution
  * Lat of landmark
  * Wlon of landmark
  * Radius
 * Below the dot rows with the landmark name above them:
  * For each image:
   * 1st column - picture name
   * 2nd column - PX residual (# of pixels in image resolution)
   * 3rd column - LN residual (# of pixels in image resolution)
   * 4th column - magnitude of PX and LN residuals (# of pixels in image resolution)
   * 5th column - the estimate linear residual (km)
  * For each overlap:
   * 1st column - overlap name
   * 2nd column - X residual (km)
   * 3rd column - Y residual (km)
   * 4rd column - Z residual (km) 
   * 5th column -  estimate linear residual (km)
  * For each limb apperation:
   * 1st column - picture name
   * 2nd column - PX residual (# of pixels in image resolution)
   * 3rd column - LN residual (# of pixels in image resolution)
   * 4th column - magnitude of PX and LN residuals (# of pixels in image resolution)
   * 5th column - the estimate linear residual (km)
 * Below the images, overlaps, and limbs list for a landmark:
  * Landmark name
  * magnitude of RMS linear residual for landmark
 * Below the single dot row at the very bottom of the image:
  * Observations - how many IMAGEFILES, overlaps, and limbs for all landmarks
  * RMS RESIDUAL - overall RMS linear residual in meters.

The user should note that residuals are the difference between observed landmark positions and those predicted by the solution (SPC).

Observed landmark positions are exactly as the name suggests, positions of a landmark calculated by the code when it inputs pictures from the spacecraft of the object.

Predicted landmark positions are those calculated by SPC when it inputs it generates a solution (map) from all the pictures collected. 

During iteration and refinement of the SPC solution, the position and attitude of the spacecraft are slightly changed over and over until the the maps match the images as best they can. At then end of each iteration SUMFILES are then updated for the new attitude and position.

Thus, when the RMS between landmark residuals is as low as possible the maps match the images well, which means the updated SUMFILE is the new estimate for space craft position and attitude.
-Line 13:
+Line 61:
- (List)
   Image name, pix residual, line residual (actual and solution should be), magnitude, km residual
   Mostly they are there for historical res
-Line 17:
+Line 62:
- (Bottom)
    Meter resolution, difference between predicted and actual 

 (Very bottom)
    Observations how many things
    RMS Residual (m) (vector residual)
+== Example of a RESIDUALS.TXT File ==
-Line 50:
+Line 89:
+ Observation # =       360180

 RMS Residual (m) =   0.78928860594347106