IQUAD The area in x,y space of each grid quadrangle is sub- 



and divided into IQUAD intervals between E, lines and 

 JQUAD JQUAD intervals between n lines. 



8. Input and Output. 



The first card input to Program GRID gives the number of conformal 

 transformation coefficients NMAX , the number of ? lines NUMXI, 

 the number of n lines NUMETA, AS* in nautical miles DELSS, the 

 first value of S* in nautical miles SSSTRT, AT* in minutes DELTT, 

 the number of water depths ND , and the number of points US used to 

 establish n = n(S ) . 



The second card gives g and Bq and the next 150 cards give the 

 mapping coefficients Bj^ and Cj^ . These 151 cards are the punched 

 output from Program CONFORM. 



The remaining 31 cards are the depths picked off a bathymetric 

 chart of the northwestern Gulf of Mexico. These depths are on a 

 constant ^-line selected by the user. 



Expansion coefficients, provided by the user, appear as statements 

 within the program after format 135. 



The reader must refer to Section III of Volume I of this report 

 for an explanation of the parameters associated with the stretched 

 shelf coordinate system for the Hurricane Carla surge simulation. 



Output from GRID consists of the transform- generated coastline and 

 seaward boundary coordinates, the transform-generated arclengths along 

 the coastline and seaward boundary, and for each of the five sections, 

 9Sp/3S* , S* , Sp , and C are listed. Additionally, the 

 trans form- generated arclengths at values of n for evenly spaced 

 increments of T* and at n values for constant increments of T 

 along the chosen g-line, the ri values along the specified 5-line 

 such that AT* is constant, and the traveltime and depths along the 

 constant C-line are printed. 



The following output is required by Program SSURGE for simulating 

 the Hurricane Carla surge. This includes the x,y coordinates of the 

 grid intersections, the scale factors y and v related to the trans- 

 formation of E, to S* and n to T* , respectively, the scale fac- 

 tor F , and the sines and cosines of theta giving the orientation of 

 the 5-axis to the x-axis. The program listing indicates when these 

 may be punched or written on tape or disk for convenient input to 

 SSURGE . 



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