Cursor Shapes

Math Cursor

When you start a new equation, the cursor automatically starts as a blinking vertical red line. When the Editor window loses focus, the cursor changes to gray and stops blinking. The vertical line is the normal cursor in MathFlow editor.

As you type, the editor will begin inserting the characters into the equation, and the cursor will move to show the insertion point. Also, a faint gray box will appear, outlining the template in which the cursor is currently located. As you move around in an equation, the gray outline shifts, giving you a visual cue about the nesting structure of the underlying MathML, as illustrated below.

In the first two illustrations, the cursor is located in the numerator and denominator of a fraction, and the outlined parent is the row template containing the entire numerator and denominator respectively. In the third illustration, the cursor is on the left edge of the fraction itself, and the outlined parent is a "wrapper" row containing the fraction itself.

Token Cursor

The Editor will automatically put characters into special MathML templates called tokens. There are tokens for variables (called an <mi> template in MathML for math identifier), numbers (<mn>), operators (<mo>), and so on.

The right and left arrow keys generally move the cursor between the tokens in the row. However, when you move the cursor over a token that contains several characters together, the cursor will take an upside down T-shape to show the extent of the grouped items by underlining them, as shown here.

Within a token, the arrow keys will move the cursor between the individual characters in the token. You can also position the cursor within a multi-character token with the mouse.

In MathML, identifier tokens with more than one character, e.g. "sin", are rendered in an upright font by default, while single character tokens are rendered in italics. If you move two alphabetic tokens together, say by deleting an intervening space, the editor will automatically merge the characters together into a single token. A similar behavior applies to numbers. By noticing the cursor shape, you can easily keep track of what characters are being grouped into tokens.

Text Cursor

The MathFlow editor also supports the MathML text template. Within a text template, characters appear in an upright font by default, and the spacebar always inserts a space. Outside a text template, the spacebar may not insert a space. See Keyboard Input for details.

When the cursor is in a text template, it changes to an "I-beam" shape.

You can insert a text template either from the layout templates palette on the toolbar (it looks like a T in a dashed box) or from the Insert menu or by using the keyboard shortcut Ctrl+T.

Cursor Embellishment for Non-MathML Elements

As the cursor moves through the equation, a small triangle may appear below the cursor, as seen in this image:

This triangle is used to indicate the presence of non-MathML markup somewhere within a given element. The example image above was created with the following MathML:

<math>
   <mrow>
      <mfrac>
         <mrow>
            <mi>a</mi>
         </mrow>
         <?foo?>
         <!--comment--!>
         <atag/>
         <mrow>
            <mi>b</mi>
         </mrow>
      </mfrac>
   </mrow>
</math>

Notice the non-MathML elements between the numerator and denominator elements of the mfrac. Technically, these non-MathML elements should be displayed in Design View in the same location as the fraction bar, which would be very confusing. Since there are many situations where this kind of problem can occur, all such situations will be displayed with the upward facing triangle below the text cursor, whenever the text cursor is "on" an element with non-MathML elements inside. If you place your mouse cursor over the triangle, the status bar will show you the name of the element that contains the non-MathML markup.

Note that you cannot edit the MathML code directly with the MathML Style Editor, but you may from time to time see the non-MathML Element cursor in documents you receive from colleagues using another type of editor, such as the MathML Structure Editor.