Calculator User Manual

Appendix A: Functions and Instructions 867
rowSwap() MATH/Matrix/Row ops menu
rowSwap( matrix1 , rIndex1 , rIndex2 ) ⇒
⇒⇒
⇒ matrix
Returns matrix1 with rows rIndex1 and rIndex2
exchanged.
[1,2;3,4;5,6]! Mat ¸




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1 2
3 4
5 6
rowSwap(Mat,1,3)
¸
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5 6
3 4
1 2
RplcPic CATALOG
RplcPic picVar [, row ][, column ]
Clears the Graph screen and places picture picVar
at pixel coordinates (
row , column ). If you do not
want to clear the screen, use
RclPic.
picVar must be a picture data type variable. row
and
column , if included, specify the pixel
coordinates of the upper left corner of the picture.
Default coordinates are (0, 0).
Note: For less than full-screen pictures, only the
area affected by the new picture is cleared.
rref() MATH/Matrix menu
rref( matrix1 [, tol ]) ⇒
⇒⇒
⇒ matrix
Returns the reduced row echelon form of matrix1 .
rref([ë2,ë2,0,ë6;1,ë1,9,ë9;
ë5,2,4,ë4]) ¸
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1 0 0 66/71
0 1 0
147
71
0 0 1 ë 62/71
Optionally, any matrix element is treated as zero
if its absolute value is less than
tol . This tolerance
is used only if the matrix has floating-point
entries and does not contain any symbolic
variables that have not been assigned a value.
Otherwise,
tol is ignored.
• If you use ¥¸ or set the mode to
Exact/Approx=APPROXIMATE, computations
are done using floating-point arithmetic.
• If
tol is omitted or not used, the default
tolerance is calculated as:
5Eë 14 ù max(dim( matrix1 ))
ù rowNorm(
matrix1 )
Note: See also ref().
rref([a,b,x;c,d,y]) ¸
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1 0
d
ø x-bø y
a
ø d-bø c
0 1
ë (cø x-aø y)
a
ø d-bø c
sec() MATH/Trig menu
sec( expression1 ) ⇒
⇒⇒
⇒ expression
sec( list1 ) ⇒
⇒⇒
⇒ list
Returns the secant of expression1 or returns a list
containing the secants of all elements in
list1 .
Note: The result is returned as a degree, gradian
or radian angle, according to the current angle
mode setting.
In Degree angle mode:
sec(45) ¸ (2)
sec({1,2.3,4})
¸
{
1
cos(1)
1.000…
1
cos(4)
}