*
* str_missing.F
*
* Ansley Manke
* 8-Feb-2011
*
* This function replaces the strings in argument 2 with the string in argument 3
* according to a mask, arg 1.
* STR_MISSING(mask, default_string, replacement_string)
*
* In this subroutine we provide information about
* the function.  The user configurable information 
* consists of the following:
*
* descr              Text description of the function
*
* num_args           Required number of arguments
*
* axis_inheritance   Type of axis for the result
*                       ( CUSTOM, IMPLIED_BY_ARGS, NORMAL, ABSTRACT )
*                       CUSTOM          - user defined axis
*                       IMPLIED_BY_ARGS - same axis as the incoming argument
*                       NORMAL          - the result is normal to this axis
*                       ABSTRACT        - an axis which only has index values
*
* piecemeal_ok       For memory optimization:
*                       axes where calculation may be performed piecemeal
*                       ( YES, NO )
* 
*
* For each argument we provide the following information:
*
* name               Text name for an argument
*
* unit               Text units for an argument
*
* desc               Text description of an argument
*
* axis_influence     Are this argument's axes the same as the result grid?
*                       ( YES, NO )
*
* axis_extend       How much does Ferret need to extend arg limits relative to result 
*


      SUBROUTINE str_missing_init(id)

      INCLUDE 'ferret_cmn/EF_Util.cmn'

      INTEGER id, arg

* **********************************************************************
*                                            USER CONFIGURABLE PORTION |
*                                                                      |
*                                                                      V

      CHARACTER*100 fcn_desc

 10   FORMAT ('Replace the strings in arg2 with the string in arg3 ',
     .       'according to a mask, arg1.')

      WRITE (fcn_desc, 10) 
      CALL ef_set_desc(id, fcn_desc)


      CALL ef_set_num_args(id, 3)
      CALL ef_set_axis_inheritance(id, IMPLIED_BY_ARGS, 
     . IMPLIED_BY_ARGS, IMPLIED_BY_ARGS, IMPLIED_BY_ARGS)
      CALL ef_set_result_type(id, STRING_RETURN)

      arg = 1
      CALL ef_set_arg_name(id, arg, 'MASK')
      CALL ef_set_arg_unit(id, arg, ' ')
      CALL ef_set_arg_desc(id, arg, 
     .  'mask: substitute arg3 in arg2 where mask=1')
      CALL ef_set_axis_influence(id, arg, YES, YES, YES, YES)
      CALL ef_set_arg_type (id, arg, FLOAT_ARG)

      arg = 2
      CALL ef_set_arg_name(id, arg, 'STR')
      CALL ef_set_arg_unit(id, arg, ' ')
      CALL ef_set_arg_desc(id, arg, 'string array')
      CALL ef_set_axis_influence(id, arg, YES, YES, YES, YES)
      CALL ef_set_arg_type (id, arg, STRING_ARG)

      arg = 3
      CALL ef_set_arg_name(id, arg, 'REPL')
      CALL ef_set_arg_unit(id, arg, ' ')
      CALL ef_set_arg_desc(id, arg, 'Scalar string to substitute')
      CALL ef_set_axis_influence(id, arg, NO, NO, NO, NO)
      CALL ef_set_arg_type (id, arg, STRING_ARG)

*                                                                      ^
*                                                                      |
*                                            USER CONFIGURABLE PORTION |
* **********************************************************************

      RETURN 
      END


*
* In this subroutine we compute the result
*
      SUBROUTINE str_missing_compute(id, arg_1, arg_2, 
     .                                   arg_3, result)

      INCLUDE 'ferret_cmn/EF_Util.cmn'
      INCLUDE 'ferret_cmn/EF_mem_subsc.cmn'

      INTEGER id

      REAL bad_flag(1:EF_MAX_ARGS), bad_flag_result

*  ! string arg and result need to be twice the length.

      REAL arg_1(mem1lox:mem1hix, mem1loy:mem1hiy, 
     .           mem1loz:mem1hiz, mem1lot:mem1hit)
      REAL arg_2(2,mem2lox:mem2hix, mem2loy:mem2hiy, 
     .           mem2loz:mem2hiz, mem2lot:mem2hit)
      REAL arg_3(2,mem3lox:mem3hix, mem3loy:mem3hiy, 
     .     mem3loz:mem3hiz, mem3lot:mem3hit)
      REAL result(memreslox:memreshix, memresloy:memreshiy,
     .            memresloz:memreshiz, memreslot:memreshit)

* After initialization, the 'res_' arrays contain indexing information 
* for the result axes.  The 'arg_' arrays will contain the indexing 
* information for each variable's axes. 

      INTEGER res_lo_ss(4), res_hi_ss(4), res_incr(4)
      INTEGER arg_lo_ss(4,1:EF_MAX_ARGS), arg_hi_ss(4,1:EF_MAX_ARGS),
     .     arg_incr(4,1:EF_MAX_ARGS)

* **********************************************************************
*                                            USER CONFIGURABLE PORTION |
*                                                                      |
*                                                                      V

      INTEGER i,j,k,l
      INTEGER i1, j1, k1, l1
      INTEGER i2, j2, k2, l2
      INTEGER i3, j3, k3, l3
      INTEGER iarg, slen2, slen3
      CHARACTER text2*2048, text3*2048

      CALL ef_get_res_subscripts(id, res_lo_ss, res_hi_ss, res_incr)
      CALL ef_get_arg_subscripts(id, arg_lo_ss, arg_hi_ss, arg_incr)
      CALL ef_get_bad_flags(id, bad_flag, bad_flag_result)

* Get replacement string
      i3=arg_lo_ss(X_AXIS, ARG3)
      j3=arg_lo_ss(Y_AXIS, ARG3)
      k3=arg_lo_ss(Z_AXIS, ARG3)
      l3=arg_lo_ss(T_AXIS, ARG3)

      CALL ef_get_string_arg_element(id, ARG3, arg_3,
     .     i3,j3,k3,l3,slen3,text3)

      i1 = arg_lo_ss(X_AXIS,ARG1)
      i2 = arg_lo_ss(X_AXIS,ARG2)
      DO 400 i=res_lo_ss(X_AXIS), res_hi_ss(X_AXIS)

         j1 = arg_lo_ss(Y_AXIS,ARG1)
         j2 = arg_lo_ss(Y_AXIS,ARG2)
         DO 300 j=res_lo_ss(Y_AXIS), res_hi_ss(Y_AXIS)

            k1 = arg_lo_ss(Z_AXIS,ARG1)
            k2 = arg_lo_ss(Z_AXIS,ARG2)
            DO 200 k=res_lo_ss(Z_AXIS), res_hi_ss(Z_AXIS)

               l1 = arg_lo_ss(T_AXIS,ARG1)
               l2 = arg_lo_ss(T_AXIS,ARG2)
               DO 100 l=res_lo_ss(T_AXIS), res_hi_ss(T_AXIS)
                  iarg = 2
 	          CALL EF_GET_STRING_ARG_ELEMENT (id, iarg, arg_2, 
     .                                      i2,j2,k2,l2, slen2, text2)
                  IF (arg_1(i1,j1,k1,l1) .EQ. 1) THEN
		     text2 = text3
		     slen2 = slen3
		  ENDIF
                  CALL EF_PUT_STRING (text2, slen2, result(i,j,k,l))

                  l1 = l1 + arg_incr(T_AXIS,ARG1)
                  l2 = l2 + arg_incr(T_AXIS,ARG2)
 100           CONTINUE

               k1 = k1 + arg_incr(Z_AXIS,ARG1)
               k2 = k2 + arg_incr(Z_AXIS,ARG2)
 200        CONTINUE

            j1 = j1 + arg_incr(Y_AXIS,ARG1)
            j2 = j2 + arg_incr(Y_AXIS,ARG2)
 300     CONTINUE

         i1 = i1 + arg_incr(X_AXIS,ARG1)
         i2 = i2 + arg_incr(X_AXIS,ARG2)
 400  CONTINUE
 

*                                                                      ^
*                                                                      |
*                                            USER CONFIGURABLE PORTION |
* **********************************************************************

      RETURN 
      END
