Syntax:        TXGRAYBAR(<expN1>,<expN2>,<expN3>,<expN4>,
                    <expN5>)

     Purpose:       Draws an area at the column and row coordinates
                    shaded by the degree indicated by <expN5>. See
                    Shading printout included in Demo.

     Arguments:     <expN1> is the column coordinate of bar to be
                    drawn.

                    <expN2> is the row coordinate of bar to be drawn.

                    <expN3> is the width of your bar in columns.

                    <expN4> is the height of the bar.

                    <expN5> is the percentage of shading.

     Returns:        0  Successful
                     1  Invalid number of parameters
                     2  <expN1> column parameter not numeric
                     3  <expN2> row parameter not numeric
                     4  <expN3> column width parameter not numeric
                     5  <expN4> row height parameter not numeric
                     6  <expN5> degree of shading

     Usage:         TXGRAYBAR() is useful anytime you need to draw a
                    shaded area. Particularly useful for emulating the
                    "greenbar" paper that distinguishes printed lines.

     Example:       * To draw gray bars to emulate "greenbar"

                    for i = 1 to 60
                       TXGRAYBAR( i, 01, 80, 04, 5)
                    next

     See Also:      TXPATTERNBAR(), TXCOLBOX(), TXDOTBOX()