magnetic tape may be used for further processing such as drawing contour 

 maps. No provision is made for outputting the processed data in RAPLOT 

 III because no further processing was planned for any of the field test 

 sites. Also deletion of the output statements reduces the running time 

 of the program. 



Call NTRAN statements are also used in RAPLOT II to position the 

 input tape by end of file marks. 



Section D. PROGRAM INPUT 



1. Card Input 



Input for the RAPLOT II program comes from punched cards and 

 from magnetic tape. Three program control cards are read in for each 

 file of survey data processed. Formats, and descriptions of the vari- 

 ables written onto the cards are given in Table I; names given to the 

 variables in this table are the ones employed by the program. Figure 3 

 shows a data sheet that is used for filling out the control cards. It is 

 useful not only for filling in the parameters on the cards, but also for 

 keeping track of the data files when large numbers of files are being 

 processed. 



The last 12 characters of the legend (Card 3, spaces 66-78) are used 

 for file identification. Before a file of survey data is read in, a 7- 

 word identification array called SENTNL is read in from the beginning of 

 the tape file. The first two words in SENTNL are compared with the last 

 two words in LEGEND. If a match is not found, the tape is positioned at 

 the beginning of the next file and a new SENTNL array is read in. This 

 procedure is in lines 48 through 52 of the source language listing of 

 RAPLOT II in Appendix A. It has been deleted from RAPLOT III. 



2. Tape Input 



When a RIST survey is underway in the field, data from various 

 sensors are assembled by the onboard detector system, and punched on 8- 

 channel paper tape in American Standard Code for Information Interchange 

 (ASCII) code. At present, there are seven data fields for each line of 

 record. A brief description of the variables and the tape record format 

 is given in Table II; Figure 4 is a sample listing from a paper-tape 

 data file. 



In the actual processing of the RIST data files, it has been found 

 necessary to edit the data files prior to putting them through the RAPLOT 

 II program. The edited data are written out in unformatted magnetic tape 

 files. This is why the READ statement in line 58 of the listing in 

 Appendix A is an unformatted FORTRAN READ statement. Unformatted (or 

 binary) input-output statements are much more efficient for the computer 

 to execute than formatted statements. For that reason, they are employed 

 wherever possible. RAPLOT III employs a formatted READ statement (line 

 51, Appendix B) for inputting a data file, since the need for short turn- 

 around time is greater than the need to edit data files when supporting a 

 field test. 



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