In this mode, expressions are stored as graph with operator as nodes, and arguments as end vertices. To modify an argument, click on it, modify and type the up arrow or click somewhere else. You can modify an expression by selecting it, this will copy it to the commandline, modify the commandline and type Enter to replace the selection by the commandline. Note that in selection mode, the direction keys change the selection according to the move in the graph of the expression. It is also possible to :
To leave this mode, you can click on ->cmd (copies the whole expression in commandline) or shift ->cmd (copies only the selection). Of course you can also click on a yellow button of the bandeau.
Example : enter eqw, type x
then up arrow, then
^
, then 100
, up arrow, up arrow again to select the whole
expression (x100), then -
then 1, then up arrow
twice to select x100 - 1
(remark : you can also enter directly x^100-1
and up arrow, the method above was shown because for more
complex expressions it is less error prone).
Select factor in the Cas menu, then down arrow,
right arrow, etc. to move the selection.
Select x2 + 1 with the arrow keys or with the mouse,
click on ^
then 2
then up arrow twice.
Remark : you can edit the history entries in the same manner. Note that when you press Enter, all changes are activated and xcas will recompute all answers (starting from the first modification). If you press Esc, all changes are cancelled.