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**SDEVIATIONS**(//dataset //[,//meanofset//])

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| **SDEVIATIONS** | Returns the standard deviation of a sample of a numeric set. |
| //dataset// | The label of a QUEUE with its first component field defined as a REAL. |
| //meanofset// | A numeric constant or variable representing the average of the data set's values. |

**SDEVIATIONP **computes the standard deviation of a given population data set. SDEVIATIONS computes the standard deviation of a given sample data set. The 'Sample' function call should be used only if the data set contains less than all of a population's values. The function operates on the numeric set defined by all the entries in the first component of the designated QUEUE (//dataset//).

The optional parameter helps to optimize the function. If not provided, the value is computed internally by the function.

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The passed data set does not have to be sorted. The function copies the passed set. The passed data set is unchanged.

**Return DataType:**     REAL

**Example:**

**StatSetXY  QUEUE,PRE()**

**X            REAL**

**           END**

**StandardDeviation    REAL**

** CODE                                  !free the QUEUE**

**  CLEAR(STADAT:RECORD)               !clear the record buffer**

**  STADAT:Id = STA:Id                 !prime the record buffer**

**  STADAT:ItemNumber = 1**

**  SET(STADAT:KeyIdItemNumber,STADAT:KeyIdItemNumber !position file pointer**

**  LOOP                               !load the QUEUE**

**    NEXT(StatisticsData)             !read next record**

**    IF ERRORCODE() OR STADAT:Id NOT = STA:Id**

**      BREAK**

**    ELSE**

**      StatSetX:X = STADAT:X          !load the QUEUE buffer**

**      ADD(StatSetX)                  !add to the QUEUE**

**    END**

**  END**

**  StandardDeviation = SDEVIATIONS(StatSetX)     !call SDEVIATIONS**