MR8740T_user_manual_eng_20191016H.pdf - 第172页

167 Conguring W aveform Calculation Settings When an expression includes an operator MOV , SLI , DIF , DIF2 , PLEVEL , or ATA N 2 (about second parameter) The operators above require a comma and second parameter to foll…

166

Conguring Waveform Calculation Settings

(To manually specify the scale setting for the calculation result)

(1)

(2)

(1) Click the arrow buttons to choose a calculation channel.

(2) Click [Upper and lower limit value] to specify the upper and lower limit values of the

calculation result.

(To making calculations using measured data)

Click [Execute].

(To make calculations during measurement)

Click the start icon.

Once the instrument has acquired waveforms, it displays waveforms calculated.

Entering arithmetic expressions

• The length of each arithmetic expression is limited to 80 characters.

• You can enter a 30-digit numbers or less in arithmetic expressions (for constants, 5-digit number

or less ).

• Use an asterisk (

) and slash (/) for multiplication and division, respectively.

• If an expression you enter includes an error (its frame is lled with red), all calculation results

become zero.

• Entering a complex, long arithmetic expression causes the frame of the entry box to become red.

Divide an expression into two or more.

ABS(CH(1,1)) + CH(1,2)

CH(1,3) − (CH(2,1) + CH(2,2))

ABS(CH(2,1))/DIF(CH(1,1),1)

1 2 3

• Making division by zero results in an output of an overowed value.

(for a positive divisor, +9.9999E+29; for a negative divisor, −99.9999E+29)

• You can use calculation result Zi in other calculations. Expression Zn, however, can include only

result Zn-1 or earlier.

Example: You can use results Z1, Z2, and Z3 for expression Z4)

167

Conguring Waveform Calculation Settings

When an expression includes an operator MOV, SLI, DIF, DIF2, PLEVEL, or ATAN2 (about second

parameter)

The operators above require a comma and second parameter to follow the rst parameter, which is

enclosed in parentheses.

Examples of operators and settings

Operator Setting Setting example

MOV (moving average)

SLI (parallel move)

Specify the number of moving

points.

Setting range

MOV (moving average): 1 to 5000

SLI: −5000 to 5000

If you omit the second parameter,

the instrument species [1] to make

calculations.

To calculate a 10-point moving

average of the CH1 waveform

MOV(CH1,10)

DIF (differential)

DIF2 (2nd-order differential)

Specify a sampling interval for

differentials Normally specify “1.”

Specify a larger number, however,

to monitor the variation in a slowly

changing waveform.

Setting range for DIF and DIF2: 1

to 5000

If you omit the second parameter,

the instrument species [1] to make

calculations.

To calculate differentials of data

acquired across CH2 at intervals

of 20 sampled points.

MOV(CH2,20)

PLEVEL (level at time) Specify a time from a trigger point.

If you omit the second parameter,

the instrument species [0] to make

calculations.

Obtains the level a signal reaches

1 ms after the trigger point

generated from a signal acquired

across CH1-3.

PLEVEL(CH(1,3),0.001)

ATAN2 (2-argument arc tangent) When you type “ATAN2(y,x),”

the instrument calculates the

expression ATAN(y/x). (p. 170)

If you omit “x,” the instrument

makes calculations supposing

that x equals 1.0. You can specify

“CH,” “Z,” or a constant only at “x.”

No function or expression can be

specied. Not available

To calculate 2-argument arc

tangent of CH1-1 / CH1-2

ATAN2(CH(1,1),CH(1,2))

If a calculation result is overowing (OVER)

• The instrument regards a calculation result that falls within the following range as an overow.

1. Greater than +9.9999E+29

2. Less than −9.9999E+29

• The instrument assigns +9.9999E+29 to positive overows, and −9.9999E+29 to negative

overows.

• Trace cursors (A through H) read +9.9999E+29 at a positively overowing point, and

−9.9999E+29 at a negatively overowing point.

Waveform Calculation Function

168

Conguring Waveform Calculation Settings

Calculation result

Example: To display the waveform processed through the absolute value calculation using a

waveform acquired across CH1_1

Arithmetic expression Z1= ABS(CH(1,1))

Waveform acquired across CH1-1

Calculated absolute value Z1