# is_SOS_var Returns if the variable is SOS (Special Ordered Set) or not. unsigned char is_SOS_var(lprec *lp, int column); Return Value is_SOS_var returns TRUE (1) if the variable is a SOS var, FALSE (0) if not. Parameters lp Pointer to previously created lp model. See return value of make_lp, copy_lp, read_lp, read_LP, read_mps, read_freemps, read_MPS, read_freeMPS, read_XLI column The column number of the variable that must be checked. It must be between 1 and the number of columns in the lp. Remarks The is_SOS_var function returns if a variable is a SOS variable or not. Default a variable is not SOS. A variable becomes a SOS variable via add_SOS. See Special Ordered Sets for a description about SOS variables. Example
    #include <stdio.h>
    #include <stdlib.h>
    #include "lp_lib.h"

    int main(void)
    {
      lprec *lp;
      int isSOS;

      /* Create a new LP model */
      lp = make_lp(0, 1);
      if(lp == NULL) {
        fprintf(stderr, "Unable to create new LP model\n");
        return(1);
      }

      isSOS = is_SOS_var(lp, 1); /* will return 0 since the variable is not an SOS var at this point */

      delete_lp(lp);
      return(0);
    }
lp_solve API reference See Also make_lp, copy_lp, read_lp, read_LP, read_mps, read_freemps, read_MPS, read_freeMPS, read_XLI, add_SOS