ACK has no effect on control alarms. Control alarms that come due are automatically acknowledged and saved in the system alarm list.

Access:

…ÓTOOLS ALRM ACK

(Ó is the right-shift of the 9 key).

Flags:

Repeat Alarms Not Rescheduled (–43), Acknowledged Alarms Saved (–44)

Input/Output:

None

 

See also:

ACKALL

 

 

 

 

 

ACKALL

Command

 

Type:

 

Description:

Acknowledge All Alarms Command: Acknowledges all past-due alarms.

 

ACKALL clears the alert annunciator if there are no other active alert sources (such as a low

 

battery condition).

 

 

ACKALL has no effect on control alarms. Control alarms that come due are automatically

 

acknowledged and saved in the system alarm list.

Access:

…ÓTOOLS ALRM ACKALL

( Óis the right-shift of the 9 key).

Flags:

Repeat Alarms Not Rescheduled (–43), Acknowledged Alarms Saved (–44)

Input/Output:

None

 

See also:

ACK

 

 

 

 

 

ACOS

Analytic Function

 

Type:

 

Description:

Arc Cosine Analytic Function: Returns the value of the angle having the given cosine.

 

For a real argument x in the domain –1 ≤x ≤ 1, the result ranges from 0 to 180 degrees (0 to π

 

radians; 0 to 200 grads).

 

 

A real argument outside of this domain is converted to a complex argument, z = x + 0i, and the

 

result is complex.

 

 

The inverse of COS is a relation, not a function, since COS sends more than one argument to the

 

same result. The inverse relation for COS is expressed by ISOL as the general solution

 

 

s1*ACOS(Z)+2*π*n1

 

The function ACOS is the inverse of a part of COS, a part defined by restricting the domain of

 

COS such that:

 

 

•

each argument is sent to a distinct result, and

 

•

each possible result is achieved.

 

The points in this restricted domain of COS are called the principal values of the inverse relation. ACOS in its entirety is called the principal branch of the inverse relation, and the points sent by ACOS to the boundary of the restricted domain of COS form the branch cuts of ACOS.

The principal branch used by the calculator for ACOS was chosen because it is analytic in the regions where the arguments of the real-valuedinverse function are defined. The branch cut for the complex-valued arc cosine function occurs where the corresponding real-valued function is undefined. The principal branch also preserves most of the important symmetries.

The graphs below show the domain and range of ACOS. The graph of the domain shows where the branch cuts occur: the heavy solid line marks one side of a cut, while the feathered lines mark the other side of a cut. The graph of the range shows where each side of each cut is mapped under the function.

These graphs show the inverse relation s1*ACOS(Z)+2*π*n1 for the case s1=1 and n1 = 0. For other values of s1 and n1, the vertical band in the lower graph is translated to the right or to the left. Taken together, the bands cover the whole complex plane, which is the domain of COS.

3-6 Full Command and Function Reference