ZANG: Zenithal Angle Observation

This record specifies a zenithal angle observation. A zenithal angle is measured at the from-station from the zenith down to the to-station.
The coefficient of refraction must be from 0.03 to 0.23 (0.13 ± 0.10). If a value less than 0.03 is given, no refraction correction is made. If a value greater than 0.23 is given, it is set to 0.23.

This record has two possible formats, a long parameter name format, and a short parameter name format. If column 10 contains an asterisk (*) the long name format is expected, otherwise the short name format is expected.
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The short parameter format of this record is as follows (from column - to column: description): 

• 002-005: ZANG
• 007-009: Sigma record identifier (see the SIGM record)
• 010: (blank)
• 011-022: From-station name
• 024-035: To-station name
• 050: Sign (-/+/ ) of zenithal angle observation
• 051-053: Degrees of zenithal angle observation
• 055-056: Minutes of zenithal angle observation
• 058-064: Seconds of zenithal angle observation
• 066-075: Standard deviation of zenithal angle observation
• 077-086: Coefficient of refraction

The long parameter format of this record is as follows (from column - to column: description): 

• 002-005: ZANG
• 007-009: Sigma record identifier (see the SIGM record)
• 010: * (asterisk)
• 011-041: From-station name
• 043-073: To-station name
• 075: Sign (-/+/ ) of zenithal angle observation
• 076-078: Degrees of zenithal angle observation
• 080-081: Minutes of zenithal angle observation
• 083-089: Seconds of zenithal angle observation
• 091-100: Standard deviation of zenithal angle observation
• 102-111: Coefficient of refraction