The Rounding Environment Variable - Maple Programming Help

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The Rounding Environment Variable

 

Calling Sequence

Parameters

Description

Examples

Calling Sequence

Rounding := x

Parameters

x

-

one of 0, nearest, infinity, -infinity, simple

Description

• 

The Rounding environment variable controls the rounding of floating-point results.

• 

There are five rounding modes available in Maple.

  

 

Rounding Mode

Meaning

 

 

nearest

round to the nearest possible value,

 

with ties resolved by rounding to the nearest even

0

round towards zero

infinity

round towards positive infinity

-infinity

round towards negative infinity

simple

round to the nearest possible value,

 

with ties resolved by rounding up

 

 

• 

The value of Rounding is changed by using the assignment operator.  The default value of Rounding is nearest.

• 

To determine the current value of Rounding during a Maple session, enter the command Rounding;.

• 

The rounding mode determines the sign of 0 when it cannot be obtained otherwise.

• 

Infinities always round to themselves, independent of the rounding value.

• 

Maple fully evaluates environment variables such as Rounding. Because Rounding is an environment variable, any assignments to it inside a procedure body are undone upon exit from the procedure.

Examples

Rounding

nearest

(1)

f := proc()
    print( "Entering f. Rounding is", Rounding );
    Rounding := -infinity;
    print( "The current value of Rounding is", Rounding );
end proc:

f

Entering f. Rounding is,nearest

The current value of Rounding is,

(2)

Rounding

nearest

(3)

When returning from f in the procedure above, Maple resets Rounding to its value on entry to f.

1.410

28.92546550

(4)

Rounding0

Rounding0

(5)

1.410

28.92546549

(6)

Roundingnearest

Roundingnearest

(7)

2.2.

0.

(8)

Rounding

Rounding

(9)

2.2.

−0.

(10)

See Also

assignment

Default0

environment

float

infinity

last_name_eval

round

type/infinity

type[float]