Description of the illustration linear_regr.eps
{ REGR_SLOPE | REGR_INTERCEPT | REGR_COUNT | REGR_R2 | REGR_AVGX | REGR_AVGY | REGR_SXX | REGR_SYY | REGR_SXY } (expr1 , expr2) [ OVER (analytic_clause) ]
{ REGR_SLOPE | REGR_INTERCEPT | REGR_COUNT | REGR_R2 | REGR_AVGX | REGR_AVGY | REGR_SXX | REGR_SYY | REGR_SXY } (expr1 , expr2) [ OVER (analytic_clause) ]