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Concatenation, Cond – Texas Instruments TI-86 User Manual

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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

L1

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