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HP 48gII User Manual

Page 279

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Page 9-4

Vectors vs. matrices
To see the

@VEC@ key in action, try the following exercises:

(1) Launch the Matrix Writer (

„²). With @VEC and @GO

selected,

enter

3`5`2``. This produces [3. 5. 2.]. (In RPN

mode, you can use the following keystroke sequence to produce the
same result:

3#5#2``).

(2) With

@VEC

@@

deselected and

@GO

selected,, enter

3#5#2``. This produces [[3. 5. 2.]].


Although these two results differ only in the number of brackets used, for the
calculator they represent different mathematical objects. The first one is a
vector with three elements, and the second one a matrix with one row and
three columns. There are differences in the way that mathematical operations
take place on a vector as opposite to a matrix. Therefore, for the time being,
keep the soft menu key

@VEC

selected while using the Matrix Writer.


The

WID key is used to decrease the width of the columns in the

spreadsheet. Press this key a couple of times to see the column width
decrease in your Matrix Writer.
The

@WID

key is used to increase the width of the columns in the

spreadsheet. Press this key a couple of times to see the column width
increase in your Matrix Writer.
The

@GO

key, when selected, automatically selects the next cell to

the right of the current cell when you press

`. This option is

selected by default.
The

@GO

key, when selected, automatically selects the next cell below

the current cell when you press

`.


Moving to the right vs. moving down in the Matrix Writer
Activate the Matrix Writer and enter

3`5`2`` with the

@GO

key selected (default). Next, enter the same sequence of numbers with

the

@GO

key selected to see the difference. In the first case you entered a

vector of three elements. In the second case you entered a matrix of three
rows and one column.

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