Help > Authoring > Equations > Using the Equation Editor > Equation Editor Components > The Equation Editor Marker
  
The Equation Editor Marker
The marker is a pentagonal box. It points to the place of insertion — either to the right or to the left. The marker also serves as a starting point for selecting parts of an equation by highlighting.
By changing the appearance of its outline, the marker indicates whether the characters it surrounds comprise a complete structure, or if they are a component of a larger mathematical structure. When the markerhas a dotted outline, the characters it contains are a component of a larger construct, for example, the denominator of a fraction, the index of a radical, or an element of a matrix.
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While the marker can encompass all added rows of equations in the Equation Editor window, deleting the equation is the only action you can perform with all rows encompassed. Other actions can only be performed on one row (considered one equation), at a time.
To find the next largest construct:
1. Press f5.
2. Press f5 again to expand the marker to the next larger construct; repeat until it encompasses the entire equation.
To find the next smallest construct:
1. Press SHIFT+f5.
2. Press SHIFT+f5 again to contract to a component of the construct.
These components generally cannot be deleted. After a delete or cut, an input box represents an empty component.
To position the marker:
1. Click on a character in the Equation Editor window.
To move the marker's insertion point:
1. Press the left arrow or the right arrow (whichever points in the desired direction.)
2. Press the key once to reverse the marker's insertion point. Press it again to move the position of the marker one character to the left or right, respectively, until a change in component level or an endpoint of the expression is reached.
The tab key cycles through the various components of a given construct, such as a matrix. The behavior of these keys is best learned by experimentation. Invalid operations produce error messages.