P E R M I N :

This Command may be used for generating a direct access file (PRONEQS) which contains a record for each term in the normal equations that cross references the station data or auxiliary paramater file to the normal equation file. It also contains profile information required to build the normal equations.

A minimum profile is computed in such a way as to maximize the number of zero terms above the last non-zero term in any column considering an upper triangular matrix. This will reduce the operations required to compute the matrix and also reduce the number of fillin terms generated.

One can optionally produce a list of station to station interconnections within the normal equations. The program will list any stations which have less than a minimum number of interconnections. The process is halted if a station is detected without any observations, unless that station is within the junction band of the normal equations during a partially reduced adjustment.

     Example.

     cd /              <== Go to default directory
     cd /data/sudbury  <== Go to data directory
     PERMIN            <== Perform the minimization
     TYPE PERMIN.LIS   <== Examine the results
 

or

For the Vax the user enters a parameter in the batch procedure

 SUBMIT/PARAMETER=(DATA.SUDBURY)/NOPRINT GHOST$CMND:PERMIN 

program output

     
    Perform minimization
    ====================
    Number of Stations                 =       132
    Number of Auxiliary Parmeters.     =         0
    Number of Fixed stations           =         1
    Number of Junction stations        =         0
    Number of Junction Aux. Par        =         0
    Maximum connections                =        13
    

Lists of stations are output in groups. The groups are ordered in the Normal equation order. The first group is the fixed station group followed by correlated groups of stations. If this is a Helmert block adjustment then this will be followed by groups in the junction part of the Normal equation matrix.

   The following numbers are listed as found in the FIXED STATION band of the Normal equation matrix
[28642     ] 
   The following numbers are listed as found in the CORRELATED STATIONS band of the Normal equation matrix
[23600     ] [55A069    ] [A20966    ] [55A051    ] [55A138    ] [55A146    ] [79A028    ] [55A124    ] [77X385    ] [55A019    ] 
[A483537   ] [79A628    ] [82A452    ] [79A566    ] [85X405    ] [84A150    ] [52A805D   ] [79A040    ] [79A552    ] [52A796D   ] 

The user can list the various connections between station and auxiliary parameters. The default is to list only stations with minimum connections.

   
       Station     Direction Dist Azimuth   PE  PD  PR ELD
                    # out in       out in                                        Connections  in  normal  equations
       ==========  ---------------------------------------    ==========  ==========  ==========  ==========  ==========  ==========
    46 84A150       0   0  0    0    0  0    0   3   0   0    79A040      77X1052     21ACC3A     79A552      20A046      79A507    
                                                              79A566      A483537   
    49 52A805D      0   0  0    0    0  0    0   3   0   0    55A032      82A469      52A796D     79A628      77X385      55A019    
                                                              85X405      82A452    
    52 79A040       0   0  0    0    0  0    0   4   0   0    55A032      21ACC3A     77X385      79A552      20A046      79A028    
                                                              84A150      55A124      79A566      A483537     23600       55A051    
                                                              55A069  
 

• Station
  Identifies the station or point in the network
• Direction -
  # - Total number of directions at this station
  out- number measured from this station
  in number measured into this station
• Dist
  Number of distances measured at this station
• Azimuth
  out -Number of azimuths measured from this station
  in - Number of azimuths using this station as a target
• PE -
  Number of position equation observations at this station
• PD
  Number of pposition difference differences measured from this station
• PR
  Number of Partially reduced normal equations (ncludes station adjustment and constraints as well)
• ELD
  Number of elevation differencs measured at this station
• Connections in Normal equation matirx - can be used to identify the observations in the first half of the file. For example for the first line there are 3 observations in the normal equation matrix from station 84A150. From these 3 observations there are direction connections to 79A040, 77X1052, 21ACC3A, 79A552, 20A046, 79A507 and 79A566. 7

  The summary of the Normal equation matrix.

                                                                 
      Summary of normal equations formation
      =====================================
      Number of unknowns                 =       393
      Number  Normal equation terms      =     17994
      Maximum column height              =        99 (av.  =    45)
      Number of Heresi records           =         2 (size = 10000)
      

  • Number of unknowns
    Number of equations in the Normal equation matrix
  • Number of Normal equation terms
    sum of the terms above the diagonal to the last non zero term
  • Maximum column height
    The maximum number of terms above a diagonal term to the last non zero term
  • Number of Heresi records
    An estimate of the size of the heresi vectors can be used to esimate time for large adjustments