Next: Language Modes, Previous: Declarations, Up: Mode Settings

### 7.7 Display Modes

The commands in this section are two-key sequences beginning with the `d` prefix. The `d l` (`calc-line-numbering`) and `d b` (`calc-line-breaking`) commands are described elsewhere; see Stack Basics and see Normal Language Modes, respectively. Display formats for vectors and matrices are also covered elsewhere; see Vector and Matrix Formats.

One thing all display modes have in common is their treatment of the `H` prefix. This prefix causes any mode command that would normally refresh the stack to leave the stack display alone. The word “Dirty” will appear in the mode line when Calc thinks the stack display may not reflect the latest mode settings.

The `d <RET>` (`calc-refresh-top`) command reformats the top stack entry according to all the current modes. Positive prefix arguments reformat the top n entries; negative prefix arguments reformat the specified entry, and a prefix of zero is equivalent to `d <SPC>` (`calc-refresh`), which reformats the entire stack. For example, `H d s M-2 d <RET>` changes to scientific notation but reformats only the top two stack entries in the new mode.

The `I` prefix has another effect on the display modes. The mode is set only temporarily; the top stack entry is reformatted according to that mode, then the original mode setting is restored. In other words, `I d s` is equivalent to `H d s d <RET> H d (`old mode`)`.