Campbell Scientific CR9000X Measurement and Control System - Manual (Page 217)

Section 6. Data Table Declarations and Output Processing Instructions
Parameter
& Data Type Enter SAMPLEMAXMIN PARAMETERS
Reps
Constant The number of values to sample. When repetitions are greater than 1, the source
must be an array.
Source
Variable The Source is the name of the variable or variable array that is sampled when a
new maximum or minimum occurs for the preceding Maximum or Minimum
instruction.
DataType A code to select the data storage format. Read More: See Section 4.2.4.4 Data Types
Entry Description
IEEE4 IEEE four-byte floating point
FP2 Campbell Scientific two-byte floating point
UINT2 2 Byte unsigned integer
Constant
Long 32 bit long integer
DisableVar
Constant,
Variable or The DisableVar is a Constant, Variable, or Expression that is used to determine
whether the current measurement is included in the values to evaluate for a
maximum or minimum
Value Result
0 Process current input
Expression
≠0 Do not process current input
StdDev (Reps, Source, DataType, DisableVar)
StdDev calculates the standard deviation of the Source(s) over the output
interval.
δ( ) / / x x x N N
i i
i
i N
i
i N
= −
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟
⎛
⎝
⎜
⎜
⎞
⎠
⎟
⎟
⎛
⎝
⎜
⎜⎜
⎞
⎠
⎟
⎟⎟
=
=
=
=
∑ ∑
2
1
2
1
1
2
( )
δ where x is the standard deviation of x, and N is the number of samples
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