calc: Editing Stack Entries
6.2 Editing Stack Entries
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The ‘`’ (‘calc-edit’) command creates a temporary buffer (‘*Calc Edit*’)
for editing the top-of-stack value using regular Emacs commands. Note
that ‘`’ is a grave accent, not an apostrophe. With a numeric prefix
argument, it edits the specified number of stack entries at once. (An
argument of zero edits the entire stack; a negative argument edits one
specific stack entry.)
When you are done editing, press ‘C-c C-c’ to finish and return to
Calc. The <RET> and <LFD> keys also work to finish most sorts of
editing, though in some cases Calc leaves <RET> with its usual meaning
(“insert a newline”) if it’s a situation where you might want to insert
new lines into the editing buffer.
When you finish editing, the Calculator parses the lines of text in
the ‘*Calc Edit*’ buffer as numbers or formulas, replaces the original
stack elements in the original buffer with these new values, then kills
the ‘*Calc Edit*’ buffer. The original Calculator buffer continues to
exist during editing, but for best results you should be careful not to
change it until you have finished the edit. You can also cancel the
edit by killing the buffer with ‘C-x k’.
The formula is normally reevaluated as it is put onto the stack. For
example, editing ‘a + 2’ to ‘3 + 2’ and pressing ‘C-c C-c’ will push 5
on the stack. If you use <LFD> to finish, Calc will put the result on
the stack without evaluating it.
If you give a prefix argument to ‘C-c C-c’, Calc will not kill the
‘*Calc Edit*’ buffer. You can switch back to that buffer and continue
editing if you wish. However, you should understand that if you
initiated the edit with ‘`’, the ‘C-c C-c’ operation will be programmed
to replace the top of the stack with the new edited value, and it will
do this even if you have rearranged the stack in the meanwhile. This is
not so much of a problem with other editing commands, though, such as ‘s
e’ (‘calc-edit-variable’; 
Operations on Variables).
If the ‘calc-edit’ command involves more than one stack entry, each
line of the ‘*Calc Edit*’ buffer is interpreted as a separate formula.
Otherwise, the entire buffer is interpreted as one formula, with line
breaks ignored. (You can use ‘C-o’ or ‘C-q C-j’ to insert a newline in
the buffer without pressing <RET>.)
The ‘`’ key also works during numeric or algebraic entry. The text
entered so far is moved to the ‘*Calc Edit*’ buffer for more extensive
editing than is convenient in the minibuffer.
Info Catalog
calc: Stack Manipulation
calc: Stack and Trail
calc: Trail Commands