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

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| **SDEVIATIONP** | Returns the standard deviation of the entire population 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 (optional). |

**SDEVIATIONP **computes the standard deviation of a given population data set. SDEVIATIONS computes the standard deviation of a given sample data set. The 'Population' function call should be used only if the data set contains 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(StatSetX)                     !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 = SDEVIATIONP(StatSetX)     !call SDEVIATIONP**