Tools for Finding Problems in the Data or Processing

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Tools for Finding Problems in the Data or
Processing
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Topics to be covered

• Postfit editing
• Sky plots of residuals
• CVIEW interactive data viewer
• Common failure modes

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Skyplots

• To make them
• Check that GMT software is installed
• Include following command in autcln.cmd
• POST phs_res_root DPH
• Will create DPH files
• Examples
• HOLC in California
• Results from /dell3/tah/glob99 using display

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HOLC skyplots
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CVIEW

• an interactive viewer of GPS data
• allows editing and cycle slip repair
• seldom used now
• autcln works well on most data
• useful for diagnosis when autcln fails
• example use of cview
• To retain C-files to read with cview, use-e
  option in sh_gamit.
• Examine /dell3/tah/iap02/013r

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Failures

• Reported in the GAMIT.fatal files
• Most common modes of failure
• setup errors
• receiver and antenna information
• bad apriori coordinates
• tables out of range
• Examples
• fatal errors in yesterday's tutorial

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Summary

• Examine sky plots
• phase residuals help evaluate quality
• Examine GAMIT.fatal
• diagnose upstream problems