--- capa/capa51/pProj/capaCommon.c	2002/09/20 21:27:49	1.22
+++ capa/capa51/pProj/capaCommon.c	2004/06/01 19:57:18	1.24
@@ -2638,7 +2638,7 @@ answers_string(mode, p)int mode;Problem_
              if(len_dd == 0 ) {  /* no unit_str */
                sprintf(ans_str," %s [%s,%s]\n\n", str_aa,str_bb,str_cc);
              } else {
-               sprintf(ans_str," %s [%s,%s] $%s$\n\n", str_aa,str_bb,str_cc,p->unit_str);
+               sprintf(ans_str," %s [%s,%s] $\\mathrm{%s}$\n\n", str_aa,str_bb,str_cc,p->unit_str);
              }
              capa_mfree((char *)str_aa); 
 	     capa_mfree((char *)str_bb); 
@@ -2660,7 +2660,7 @@ answers_string(mode, p)int mode;Problem_
              if(len_dd == 0 ) {  /* no unit_str */
                sprintf(ans_str," %s\n", str_bb);
              } else {
-               sprintf(ans_str," %s $%s$\n", str_bb,p->unit_str);
+               sprintf(ans_str," %s $\\mathrm{%s}$\n", str_bb,p->unit_str);
              }
              capa_mfree((char *)str_bb);
            }
@@ -2897,6 +2897,16 @@ answers_string(mode, p)int mode;Problem_
 }
 
 
+int check_for_unit_fail(int result)
+{
+  int ret;
+  ret = (result == UNIT_FAIL ||
+	 result == UNIT_IRRECONCIBLE ||
+	 result == UNIT_INVALID_STUDENT3 ||
+	 result == UNIT_INVALID_STUDENT2 ||
+	 result == UNIT_INVALID_STUDENT1);
+  return ret;
+}
 
 /* ------------------------------ called from capalogin */
 /*  impose stronger checking on the user input string *answer   */
@@ -2947,7 +2957,8 @@ capa_check_ans(ai,ans, error) AnswerInfo
               outcome = split_num_unit(ans,&n_part,num_str,unit_str);
               if( outcome > 1 ) { /* with both num and unit parts or only unit part */
                 if( u_p != NULL ) {
-		  if (UNIT_FAIL == (result = check_correct_unit(unit_str,u_p,&scale))) {
+		  result = check_correct_unit(unit_str,u_p,&scale);
+		  if (check_for_unit_fail(result)) {
 		    *error=strsave(unit_str);
 		  }
                 } else { /* what to do when no unit is specified but student entered a unit? */
@@ -2959,7 +2970,7 @@ capa_check_ans(ai,ans, error) AnswerInfo
                   result = NO_UNIT;
                 }
               }
-              if( (result != NO_UNIT) && (result != UNIT_FAIL) && ( result != UNIT_NOTNEEDED) ) {
+              if( (result != NO_UNIT) && (!check_for_unit_fail(result)) && ( result != UNIT_NOTNEEDED) ) {
                 if( t == ANSWER_IS_FLOAT ) {
                   target = (double)atof(s); /* real number */
                 } else {
@@ -3097,7 +3108,7 @@ capa_check_answer(p, answer, error) Prob
   fmt      = p->ans_fmt;
   calc_type = p->calc;
   unit_str[0]=0;
-  
+
   switch(type) {
     case ANSWER_IS_INTEGER:
     case ANSWER_IS_FLOAT:
@@ -3113,7 +3124,8 @@ capa_check_answer(p, answer, error) Prob
               outcome = split_num_unit(answer,&n_part,input,unit_str);
               if( outcome > 1 ) { /* with both num and unit parts or only unit part */
                 if( p->ans_unit != NULL ) {
-		  if ( UNIT_FAIL == ( result = check_correct_unit(unit_str,p->ans_unit,&scale) ) ) {
+		  result = check_correct_unit(unit_str,p->ans_unit,&scale);
+		  if (check_for_unit_fail(result)) {
 		    *error=strsave(unit_str);
 		  }
                 } else { /* what to do when no unit is specified but student entered a unit? */
@@ -3125,7 +3137,7 @@ capa_check_answer(p, answer, error) Prob
                   result = NO_UNIT;
                 }
               }
-              if( (result != NO_UNIT) && (result != UNIT_FAIL) && ( result != UNIT_NOTNEEDED) ) {
+              if( (result != NO_UNIT) && (!check_for_unit_fail(result)) && ( result != UNIT_NOTNEEDED) ) {
                 if( type == ANSWER_IS_FLOAT ) {
                   target = (double)atof(correct); /* real number */
                 } else {
@@ -3400,7 +3412,7 @@ Problem_t *p; char **answers; int cnt; c
     done = ii = 0;
     result = 0;
     while( !done ) { /* check if any of the outcome has failed on units */
-      if( (outcomes[ii] == UNIT_FAIL) ||
+      if( (check_for_unit_fail(outcomes[ii])) ||
           (outcomes[ii] == NO_UNIT)   ||
           (outcomes[ii] == UNIT_NOTNEEDED) ) {
          result = outcomes[ii];
@@ -3447,7 +3459,7 @@ Problem_t *p; char **answers; int cnt; c
       }
     }
     for (ii=0;ii<cnt;ii++) {
-      if( (outcomes[ii] == UNIT_FAIL) ||
+      if( (check_for_unit_fail(outcomes[ii])) ||
           (outcomes[ii] == SIG_FAIL)   ||
           (outcomes[ii] == UNIT_NOTNEEDED) ) {
 	capa_mfree(errormsg[ii]);
@@ -3465,7 +3477,7 @@ Problem_t *p; char **answers; int cnt; c
      result = capa_check_answer(p, answers[0], error);
      ii = 1;  ai = p->ans_list;
      while( (ii<p->ans_cnt) && ( (result != EXACT_ANS) && (result != APPROX_ANS) ) ) {
-       if((ii!=1)&&((result==UNIT_FAIL)||(result==SIG_FAIL)||(result==UNIT_NOTNEEDED))) {
+       if((ii!=1)&&((check_for_unit_fail(result))||(result==SIG_FAIL)||(result==UNIT_NOTNEEDED))) {
 	 capa_mfree((char*)error);
        }
        result =  capa_check_ans(ai,answers[0],error);