# SQL Sequence Grid Aggregate Var and Dev Functions

> The `seq_grid_agg_var()` and `seq_grid_agg_dev()` functions compute the variance and standard deviation for the sample volume blocks.

> Following is an example script demonstrating the `seq_grid_agg_var()` and `seq_grid_agg_dev()` functions:

>         SELECT symbol, seq_search(day, 20130101, 20130331) as Q1_13,
>             volume@Q1_13 as "Volume_Q1_13",
>             seq_grid_agg_var(volume@Q1_13, 7) as "var_Q1_13",
>             seq_grid_agg_dev(volume@Q1_13, 7) as "dev_Q1_13"
>         FROM Quote WHERE symbol='SYM0';

>         symbol
>         Q1_13{}
>         Volume_Q1_13{}
>         var_Q1_13{}
>         dev_Q1_13{}
>         ------------------------------------------------------------------------------
>         SYM0
>         {20130101, 20130104, 20130106, 20130110, 20130123, 20130125, 20130129,
>           20130213, 20130214, 20130216, 20130311, 20130326}
>         {335, 808, 45, 402, 732, 48, 805,
>           450, 385, 420, 367, 69}
>         {96397.387755, 18935.760000}
>         {310.479287, 137.607267}

> Note that the variance and standard deviation values computed for the sample volume blocks can be verified using the following table (built with Microsoft Excel version 2010):

> ##

> ## Sample script

> A sample script to demonstrate this `select` statement using xSQL can be run from the `samples/xsql/scripts/financial` directory with the following command:

>         g 7