This topic describes the syntax of mathematical statistics functions. This topic also provides examples on how to use the functions.

Function Syntax Description
corr function corr(x,y) Returns the coefficient of correlation between x and y. The return value is in the range of [0,1].
covar_pop function covar_pop(x,y) Returns the population covariance of x and y.
covar_samp function covar_samp(x,y) Returns the sample covariance of x and y.
regr_intercept function regr_intercept(y,x) Returns the y-intercept of the line for the linear equation that is determined by the (x,y) pair.
regr_slope function regr_slope(y,x) Returns the slope of the line for the linear equation that is determined by the (x,y) pair.
stddev function stddev(x) Returns the sample standard deviation of x. This function is equivalent to the stddev_samp function.
stddev_samp function stddev_samp(x) Returns the sample standard deviation of x.
stddev_pop function stddev_pop(x) Returns the population standard deviation of x.
variance function variance(x) Returns the sample variance of x. This function is equivalent to the var_samp function.
var_samp function var_samp(x) Returns the sample variance of x.
var_pop function var_pop(x) Returns the population variance of x.

corr function

The corr function returns the coefficient of correlation between x and y. A larger return value indicates a higher correlation.

Syntax

corr(x,y)

Parameters

Parameter Description
x The value of this parameter is of the double type.
y The value of this parameter is of the double type.

Return value type

The double type. The return value is in the range of [0,1].

Examples

Calculate the coefficient of correlation between the values of the request_length and request_time fields.

  • Query statement
    * | SELECT corr(request_length,request_time)
  • Query and analysis resultscorr function

covar_pop function

The covar_pop function returns the population covariance of x and y.

Syntax

covar_pop(x,y)

Parameters

Parameter Description
x The value of this parameter is of the double type.
y The value of this parameter is of the double type.

Return value type

The double type.

Examples

Calculate the population covariance of pretax profits and pretax turnovers in each minute.

  • Query statement
    *|
    SELECT
      covar_pop(PretaxGrossAmount, PretaxAmount) AS "Population covariance",
      time_series(__time__, '1m', '%H:%i:%s', '0') AS time
    GROUP BY
      time
  • Query and analysis resultscovar_pop

covar_samp function

The covar_samp function returns the sample covariance of x and y.

Syntax

covar_samp(x,y)

Parameters

Parameter Description
x The value of this parameter is of the double type.
y The value of this parameter is of the double type.

Return value type

The double type.

Examples

Calculate the sample covariance of pretax profits and pretax turnovers in each minute.

  • Query statement
    *|
    SELECT
      covar_samp(PretaxGrossAmount, PretaxAmount) AS "Sample covariance",
      time_series(__time__, '1m', '%H:%i:%s', '0') AS time
    GROUP BY
      time
  • Query and analysis resultscovar_samp

regr_intercept function

The regr_intercept function returns the y-intercept of the line for the linear equation that is determined by the (x,y) pair. x is the dependent value. y is the independent value.

Syntax

regr_intercept(y,x)

Parameters

Parameter Description
y The value of this parameter is of the double type.
x The value of this parameter is of the double type.

Return value type

The double type.

Examples

Calculate the y-intercept of the line for the linear equation that is determined by the values of the request_time and request_length fields.

  • Query statement
    * | SELECT regr_intercept(request_length,request_time)
  • Query and analysis resultsregr_slope

regr_slope function

The regr_slope function returns the slope of the line for the linear equation that is determined by the (x,y) pair. x is the dependent value. y is the independent value.

Syntax

regr_slope(y,x)

Parameters

Parameter Description
y The value of this parameter is of the double type.
x The value of this parameter is of the double type.

Return value type

The double type.

Examples

Calculate the slope of the line for the linear equation that is determined by the values of the request_time and request_length fields.

  • Query statement
    * | SELECT regr_slope(request_length,request_time)
  • Query and analysis resultsregr_slope

stddev function

The stddev function returns the sample standard deviation of x. This function is equivalent to the stddev_samp function.

Syntax

stddev(x)

Parameters

Parameter Description
x The value of this parameter is of the double or bigint type.

Return value type

The double type.

Examples

Calculate the sample standard deviation and population standard deviation of pretax incomes and display the calculated values in a line chart.

  • Query statement
    * |
    SELECT
      stddev(PretaxGrossAmount) as "Sample standard deviation",
      stddev_pop(PretaxGrossAmount) as "Population standard deviation",
      time_series(__time__, '1m', '%H:%i:%s', '0') AS time
    GROUP BY
      time
  • Query and analysis resultsstddev_pop function

stddev_samp function

The stddev_samp function returns the sample standard deviation of x.

Syntax

stddev_samp(x)

Parameters

Parameter Description
x The value of this parameter is of the double or bigint type.

Return value type

The double type.

Examples

Calculate the sample standard deviation and population standard deviation of pretax incomes and display the calculated values in a line chart.

  • Query statement
    * |
    SELECT
      stddev_samp(PretaxGrossAmount) as "Sample standard deviation",
      stddev_pop(PretaxGrossAmount) as "Population standard deviation",
      time_series(__time__, '1m', '%H:%i:%s', '0') AS time
    GROUP BY
      time
  • Query and analysis resultsstddev_pop function

stddev_pop function

The stddev_pop function returns the population standard deviation of x.

Syntax

stddev_pop(x)

Parameters

Parameter Description
x The value of this parameter is of the double or bigint type.

Return value type

The double type.

Examples

Calculate the sample standard deviation and population standard deviation of pretax incomes and display the calculated values in a line chart.

  • Query statement
    * |
    SELECT
      stddev(PretaxGrossAmount) as "Sample standard deviation",
      stddev_pop(PretaxGrossAmount) as "Population standard deviation",
      time_series(__time__, '1m', '%H:%i:%s', '0') AS time
    GROUP BY
      time
  • Query and analysis resultsstddev_pop function

variance function

The variance function returns the sample variance of x. This function is equivalent to the var_samp function.

Syntax

variance(x)

Parameters

Parameter Description
x The value of this parameter is of the double or bigint type.

Return value type

The double type.

Examples

Calculate the sample variance and population variance of pretax incomes and display the calculated values in a line chart.

  • Query statement
    * |
    SELECT
      variance(PretaxGrossAmount) as "Sample variance",
      var_pop(PretaxGrossAmount) as "Population variance",
      time_series(__time__, '1m', '%H:%i:%s', '0') as time
    GROUP BY
      time
  • Query and analysis resultsvariance

var_samp function

The var_samp function returns the sample variance of x.

Syntax

var_samp(x)

Parameters

Parameter Description
x The value of this parameter is of the double or bigint type.

Return value type

The double type.

Examples

Calculate the sample variance and population variance of pretax incomes and display the calculated values in a line chart.

  • Query statement
    * |
    SELECT
      var_samp(PretaxGrossAmount) as "Sample variance",
      var_pop(PretaxGrossAmount) as "Population variance",
      time_series(__time__, '1m', '%H:%i:%s', '0') as time
    GROUP BY
      time
  • Query and analysis resultsvariance

var_pop function

The var_pop function returns the population variance of x.

Syntax

var_pop(x)

Parameters

Parameter Description
x The value of this parameter is of the double or bigint type.

Return value type

The double type.

Examples

Calculate the sample variance and population variance of pretax incomes and display the calculated values in a line chart.

  • Query statement
    * |
    SELECT
      variance(PretaxGrossAmount) as "Sample variance",
      var_pop(PretaxGrossAmount) as "Population variance",
      time_series(__time__, '1m', '%H:%i:%s', '0') as time
    GROUP BY
      time
  • Query and analysis resultsvariance