text: /*  D8FLowPathExtremeUpmn 
    Main program for function that evaluates the extreme (either maximum or minimum) upslope value 
    from an input grid based on the D8 flow directions.  It is similar to the minimum upslope function 
    used Tarolli and Tarboton (2006).  Numerically the extreme upslope value is computed recursively 
    as the extreme of the cell value itself and the result from the function applied at grid cells 
    immediately upslope, using D8 flow directions (Tarolli and Tarboton used Dinfinity).  This is 
    intended initially for use in stream raster generation to identify a threshold of slope x area 
    product that results in an optimum (according to drop analysis) stream network.  If an outlets 
    shapefile is provided the function should only output results for the area upslope of the outlets.
  
    David G Tarboton, Teklu K Tesfa
    Utah State University     
    May 23, 2010   
    
  */
  
  /*  Copyright (C) 2010  David Tarboton, Utah State University
  
  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License 
  version 2, 1991 as published by the Free Software Foundation.
  
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
  
  A copy of the full GNU General Public License is included in file 
  gpl.html. This is also available at:
  http://www.gnu.org/copyleft/gpl.html
  or from:
  The Free Software Foundation, Inc., 59 Temple Place - Suite 330, 
  Boston, MA  02111-1307, USA.
  
  If you wish to use or incorporate this program (or parts of it) into 
  other software that does not meet the GNU General Public License 
  conditions contact the author to request permission.
  David G. Tarboton  
  Utah State University 
  8200 Old Main Hill 
  Logan, UT 84322-8200 
  USA 
  http://www.engineering.usu.edu/dtarb/ 
  email:  dtarb@usu.edu 
  */
  
  //  This software is distributed from http://hydrology.usu.edu/taudem/
  
  #include <time.h>
  #include <string.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include "commonLib.h"
  #include "shape/shapefile.h"
  
  int d8flowpathextremeup(char *pfile, char*safile, char *ssafile, int usemax, char *outletfile, int useoutlets, int contcheck, int prow, int pcol);
  
  int main(int argc,char **argv)  
  {
     char pfile[MAXLN],safile[MAXLN], ssafile[MAXLN], outletfile[MAXLN];
     int err, useoutlets,contcheck,usemax, prow=0,pcol = 0;
        
     if(argc < 2) goto errexit;
     usemax=1;  // Set defaults
     useoutlets=0;
     contcheck=1;
     if(argc == 2)
  	{
  //		printf("You are running %s with the simple use option.\n", argv[0]);
  		nameadd(pfile,argv[1],"p");
  		nameadd(safile,argv[1],"sa");
  		nameadd(ssafile,argv[1],"ssa");
      }
     if(argc > 2)
     {
  //		printf("You are running %s with the specific file names option.\n", argv[0]);
          int i=1;	
  		while(argc > i)
  		{
  			if(strcmp(argv[i],"-p")==0)
  			{
  				i++;
  				if(argc > i)
  				{
  					strcpy(pfile,argv[i]);
  					i++;
  				}
  				else goto errexit;
  			}
  			else if(strcmp(argv[i],"-sa")==0)
  			{
  				i++;
  				if(argc > i)
  				{
  					strcpy(safile,argv[i]);
  					i++;
  				}
  				else goto errexit;
  			}
                  	else if(strcmp(argv[i],"-mf")==0)
                  	{
                          	i++;
                        	  	if(argc > i)
                          	{
                                  	prow = atoi(argv[i]);
                                  	i++;
                                  	if(argc > i)
                                  	{
                                          	pcol = atoi(argv[i]);
                                          	i++;
                                  	}
                                  	else goto errexit;
                          	}
                          	else goto errexit;
                          	if(prow <=0 || pcol <=0)
                                  	goto errexit;
                  	}
  			else if(strcmp(argv[i],"-ssa")==0)
  			{
  				i++;
  				if(argc > i)
  				{
  					strcpy(ssafile,argv[i]);
  					i++;
  				}
  				else goto errexit;
  			}
  			else if(strcmp(argv[i],"-o")==0)
  			{
  				i++;
  				if(argc > i)
  				{
  					strcpy(outletfile,argv[i]);
  					i++;
  					useoutlets=1;
  				}
  				else goto errexit;
  			}
  		   else if(strcmp(argv[i],"-min")==0)
  			{
  				i++;
  				usemax=0;
  			}
  			else if(strcmp(argv[i],"-nc")==0)
  			{
  				i++;
  				contcheck=0;
  			}
  		   else goto errexit;
  		}
     }
      if((err=d8flowpathextremeup(pfile, safile, ssafile, usemax, outletfile, useoutlets, contcheck,prow,pcol)) != 0)
          printf("Flow Path Extreme Up Error %d\n",err);
  
  	return 0;
  errexit:
     printf("Simple Use:\n %s <basefilename>\n",argv[0]);
     printf("Use with specific file names:\n %s -p <pfile>\n",argv[0]);
     printf("-sa <safile> -ssa <ssafile> [-min] [-nc] [-o <outletsfile>]\n");
     printf("<basefilename> is the name of the base digital elevation model without suffixes for simple input. Suffixes 'p', 'sa' and 'ssa' will be appended. \n");
     printf("<pfile> is the name of D8 flow directions file.\n");
     printf("<safile> is the name of input file with values from which extreme upslope is to be found.\n");
     printf("<ssa> is the name of the output file with extreme upslope values.\n");
     printf("-min indicates to search for a minimum (default is max)\n");
     printf("-nc indicates to override edge contamination checking (checking is on by default)\n");
     return 0; 
  } 
     
  