Texas Instruments TI-86 - Page 286

274
Chapter 20: A to Z Function and Instruction Reference
20ATOZ.DOC TI-86, Chap 20, US English Bob Fedorisko Revised: 02/13/01 2:42 PM Printed: 02/13/01 3:05 PM Page 274 of 118
cnorm vector
Returns the sum of the absolute values of the real or
complex elements in
vector
.
[
L
1,2,
L
3]
¶
VEC
b
[
L
1 2
L
3]
cnorm VEC
b
6
Concatenation:
+
\
stringA + stringB
Returns a string consisting of
stringB
appended
(concatenated) to the end of
stringA
.
"your name:"
¶
STR
b
your name:
"Enter "+STR
b
Enter your name:
cond
MATRX MATH menu
cond squareMatrix
Returns the condition number of a real or complex
squareMatrix
, which is calculated as:
cnorm squareMatrix
¹
cnorm squareMatrix
L
1
The condition number indicates how well-behaved
squareMatrix
is expected to be for certain matrix
functions, particularly inverse. For a well-behaved
matrix, the condition number is close to 1.
log(cond squareMatrix)
indicates the number of digits
that may be lost due to round-off errors in computing
the inverse.
For a matrix with no inverse,
cond
returns an error.
[[1,0,0][0,1,0][0,0,1]]
¶
MAT1
b
[[1 0 0]
[0 1 0]
[0 0 1]]
cond MAT1
b
1
log (Ans)
b
0
[[1,2,3][4,5,6][7,8,9]]
¶
MAT2
b
[[1 2 3]
[4 5 6]
[7 8 9]]
cond MAT2
b
1.8
E
14
log (Ans)
b
14.2552725051