Texas Instruments Voyage 200, Руководство пользователя

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Appendix A: Functions and Instructions 819
For the
AUTO
setting of the
Exact/Approx
mode,
including
var
permits approximation with floating-
point coefficients where irrational coefficients
cannot be explicitly expressed concisely in terms
of the built-in functions. Even when there is only
one variable, including
var
might yield more
complete factorization.
Note: See also
comDenom()
for a fast way to
achieve partial factoring when
factor()
is not
fast enough or if it exhausts memory.
Note: See also
cFactor()
for factoring all the
way to complex coefficients in pursuit of linear
factors.
factor(x^5+4x^4+5x^3
ì
6x
ì
3)
¸
x
5
+ 4
ø
x
4
+ 5
ø
x
3
ì
6
ø
x
ì
3
factor(ans(1),x)
¸
(x
ì
.964…)
ø
(x +.611…)
ø
(x + 2.125…)
ø
(x
ñ
+ 2.227…
ø
x + 2.392…)
factor( rationalNumber )
returns the rational
number factored into primes. For composite
numbers, the computing time grows
exponentially with the number of digits in the
second-largest factor. For example, factoring a
30-digit integer could take more than a day, and
factoring a 100-digit number could take more
than a century.
Note: To stop (break) a computation, press ´ .
If you merely want to determine if a number is
prime, use
isPrime()
instead. It is much faster,
particularly if
rationalNumber
is not prime and if
the second-largest factor has more than five
digits.
factor(152417172689)
¸
123457
ø
1234577
isPrime(152417172689)
¸
false
Fill
MATH/Matrix menu
Fill
expression, matrixVar
⇒
matrix
Replaces each element in variable matrixVar with
expression .
matrixVar
must already exist.
[1,2;3,4]
!
amatrx
¸
[
1 2
3 4
]
Fill 1.01,amatrx
¸
Done
amatrx
¸
[
1.01 1.01
1.01 1.01
]
Fill
expression, listVar
⇒
list
Replaces each element in variable listVar with
expression .
listVar
must already exist.
{1,2,3,4,5}
!
alist
¸
{1 2 3 4 5}
Fill 1.01,alist
¸
Done
alist
¸
{1.01 1.01 1.01 1.01 1.01}
floor()
MATH/Number menu
floor(
expression
)
⇒
⇒ ⇒
⇒
integer
Returns the greatest integer that is

the
argument. This function is identical to
int()
.
The argument can be a real or a complex number.
floor(
ë
2.14)
¸ ë
3.
floor(
list1
)
⇒ ⇒ ⇒ ⇒
list
floor(
matrix1
)
⇒ ⇒ ⇒ ⇒
matrix
Returns a list or matrix of the floor of each
element.
Note: See also
ceiling()
and
int()
.
floor({3/2,0,
ë
5.3})
¸
{1 0
ë
6.}
floor([1.2,3.4;2.5,4.8])
¸
[
1. 3.
2. 4.
]