INTEGER FUNCTION CTYPE (ICHAR)
      INTEGER ICHAR 
      IF (.NOT. (ICHAR .GE. CHAR0 .AND. ICHAR .LE. CHAR9))GO TO 13000   
    
      CTYPE = DIGIT 
      GO TO 13001   
13000 CONTINUE  
    
      IF (.NOT. (ICHAR .GE. CHARA .AND. ICHAR .LE. CHARZ))GO TO 13002   
    
      CTYPE = LETTER
      GO TO 13003   
13002 CONTINUE  
    
      CTYPE = ICHAR 
13003 CONTINUE  
    
13001 CONTINUE  
    
      RETURN
      END