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Add Two New Scan Types: "FivePoint" and "Circle"

Modification Request 1C706

• 1. Introduction
• 2. Background
• 3. Requirements
  • 3.1 FivePoint
  • 3.2 Circle
  • 3.3 Error Messages
• 4. Design
• 5. Deployment Checklist
• 7. Test Plan
  • 7.1 Internal Testing
    • 7.1.1 FivePoint Tests
    • 7.1.1 Circle Tests
  • 7.2 Sponsor Testing
  • 7.3 Integration/Regression Tests
• Signatures
• CCC Discussion Area

1. Introduction

A user requested a "FivePoint" scan type, in which five subscans are done. The user gives a Location and an Offset. The five points are 1) the Location, 2) Location + Offset, 3) Location-Offset, 4) Location+Offset90, 5) Location-Offset90; where "Offset90" is at a 90 degree angle to the given Offset.

"Circle" is a related function in which a central location is tracked, followed by N points on a circle centered on the location.

2. Background

3. Requirements

The requirements are written as user instructions.

3.1 FivePoint

FivePoint Syntax:

FivePoint(location, startOffset, scanDuration, beamName, referenceOffset)

Parameter Info:

• location is a Catalog source name or Location object. It specifies the source which is to be tracked.
• startOffset is an Offset object. It specifies the angle from location of the 2nd subscan.
• scanDuration is a float. It specifies the length of the subscans in seconds.
• beamName is a string. It specifies the receiver beam to use for the scan. beamName can be "C", "1", "2", "3", "4" or any valid combination for the receiver you are using such as "MR12" and "MR34". The default value for beamName is "1".
• referenceOffset is an Offset object. The default is None. If present, a reference scan is done at a position of "location+referenceOffset" both before and after the five point sequence.

FivePoint does 5 subscans each of duration given by scanDuration. The first scan is at the central position given by "location"; the second is at (location + startOffset); the third at (location - startOffset), the fourth and fifth at 90 degrees to numbers 2 and 3.

If the startOffset is represented as the vector (x, y), then the offsets of the five subscans are given by:

1. ( 0, 0)
2. ( x, y)
3. ( -x, -y)
4. ( -y, x)
5. ( y, -x)

3.2 Circle

Circle Syntax:

Circle(location, startOffset, scanDuration, beamName, nPoints, referenceOffset, referenceInterval)

Parameter Info:

• location is a Catalog source name or Location object. It specifies the source which is to be tracked.
• startOffset is an Offset object. It specifies the angle from location of the 2nd subscan.
• scanDuration is a float. It specifies the length of the subscans in seconds.
• beamName is a string. It specifies the receiver beam to use for the scan. beamName can be "C", "1", "2", "3", "4" or any valid combination for the receiver you are using such as "MR12" and "MR34". The default value for beamName is "1".
• nPoints is an integer. It specifies the total number of subscans. The minimum allowable value is 3. The default is 5.
• referenceOffset is an Offset object. The default is None. If not None, a reference scan is done at the position "location+referenceOffset" both before and after the circle sequence, and after every 'referenceInterval'th subscan of the circle sequence.
• referenceInterval is an integer. Default is zero. If referenceInterval is zero or >= nPoints, reference scans are done only before and after the circle sequence. If non-zero, and < nPoints, a reference scan is done after every referenceInterval subscans of the circle sequence in addition to before and after the sequence.

All subscans are of duration given by scanDuration.

Circle does the first subscan at the specified location, the 2nd at (location + startOffset), and the remaining subscans are on a circle of diameter given by startOffset, with (nPoints - 1) at equally spaced angles around the circle.

With nPoints = 5, one observes the same points as in FivePoint, but in a different order. In Circle, the points are at sucessive angles around a circle.

If referenceOffset is given, reference scans are done as described above.

3.3 Error Messages

In the event of an illegal argument to either FivePoint or Circle, a descriptive error message will be displayed to the user in the validation output window on the Edit tab of the Observation Management GUI.

4. Design

The code for these scan types is at present in directory /users/fghigo/GBT/astrid/procs/. The programs were based on Z17 and modified appropriately.

The code can simply be taken from the diretory mentioned above and placed into the sparrow/gbt/api/turtle/src/proc area. Then Observation.py (in sparrow/gbt/api/turtle/src/proc) must also be modified to add FivePoint and Circle as valid ScanTypes.

5. Deployment Checklist

• Add user documentation for FivePoint and Circle to ScanTypes.
• Announce new ScanTypes via an e-mail to gbtlocal (if patching) or via Release Notes (if part of regular release).

7. Test Plan

7.1 Internal Testing

7.1.1 FivePoint Tests

7.1.1 Circle Tests

7.2 Sponsor Testing

7.3 Integration/Regression Tests

Signatures

APPROVED: I acknowledge that my request is fully contained in this MR, and if the SDD delivers exactly what I specified, I will be happy.

ACCEPTED: I acknowledge that I have validated the completed code according to the acceptance tests, and I am happy with the results.

Written	- F. Ghigo - 11 Oct 2006
Checked	- A. Shelton - 12 Oct 2006
Approved by Sponsor	- F. Ghigo - 11 Oct 2006
Approved by CCC	symbol - product/version - date
Accepted/Delivered by Sponsor	symbol - product/version - date

Symbols:

• Use %X% if MR is not complete (will display )
• Use %Y% if MR iscomplete (will display )

CCC Discussion Area