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The ten characters which collectively define the FIELDNAME can be partitioned into four <br />character groupings. The first group consists of the first seven characters of FIELDNAME and <br />are identical to the STRUCCODE field, also found in cntrltbl.dbf. The structure code represents a <br />condensed abbreviation of the full structure name. Character positions 8, 9, and 10, each contain <br />code letters that pertain to structure type, information source, and information type, respectively. <br />Most of the information coded in positions 8, 9, and 10 is fairly intuitive. <br />Code letters 'V' and 'S' of the 'Information Type' code (character 10) may present some confusion. <br />At certain periods of the year a canal may be diverting water under a direct river decree, while at <br />other times (generally during periods of heightened demands), the canal may also be diverting <br />water that was released from a reservoir. Often, such water 'types' (commonly called water <br />'colors') are recorded separately in historical diversion records. Thus, to maintain the 'coloring' of <br />the diversion information within a database the 'V' and 'S' codes are utilized. If water 'coloring' is <br />not indicated within a historical data table the information type is coded with an 'O' - total outflow <br />(from river). Because both 'colors' can be diverted at the same time, a diversion can have a <br />FIELDNAME for each 'color'. The comm_dly.dbf historical data table lists diversion amount by <br />'color'. The PFM adds the two 'colors' (direct flow + reservoir flow) to obtain the total diversion <br />value. <br />An example of deciphering a FIELDNAME field is as follows: The field RIVRSIDDCV can be <br />found on the first page of cntrltbl.dbf (see Appendix II). The first seven characters of <br />RIVRSIDDCV (RIVRSID) identify it with its full river structure name - Riverside Canal. The <br />next character, D, defines the structure as being a point of diversion. The last two characters, C <br />and V, denote that RIVRSIDDCV is being located in the comm_dly.dbf table and that the value of <br />this particular field refers to water diverted under a direct river decree. Note that the horizontal <br />lines shown in cntrltbl.dbf groups the FIELDNAME fields by STRUCTNAME. This illustrates that <br />many FIELDNAME fields can be associated with one specific river structure. <br />There are instances where the FIELDNAME field does not correspond to a specific river <br />structure but rather holds more generalized information. A case in point is a FIELDNAME field <br />that contains information that pertains to the entire river (as opposed to a river structure). River <br />'calling' values, for example, are considered river specific (or District specific) rather than <br />structural specific. All such river specific FIELDNAME fields are listed at the bottom (end) of <br />cntrltbl.dbf. They can be identified as having 'N /A' stored in the STRUCTNAME field. <br />The logical information (.T. or .F.) located in the UTILIZE field of cntritbl.dbf is what allows for <br />the flexibility of including or excluding certain river structures from being considered in the point <br />flow calculations. Furthermore, it allows for the disregarding of fields not necessary to perform <br />point flow calculations. Examples of fields not required in the point flow calculations include the <br />fields that are river specific (see above paragraph). Also, if identical information exists in more <br />than one Historical Data Table, the UTILIZE field signals which information source is to be used. <br />10 <br />ptflguid wpd <br />I � <br />F1 <br />F� <br />I I <br />I I <br />I I <br />u <br />I I <br />n <br />I I <br />I I <br />I I <br />I I <br />