**[P] matrix get** -- Access system matrices

__Syntax__

__mat__**rix** [__def__**ine**] *matname* **=** **get(***systemname***)**

where *systemname* is

**_b** coefficients after any estimation command
**VCE** covariance matrix of estimators after any estimation command
**Rr** constraint matrix after **test**
**Cns** constraint matrix after any estimation command

__Description__

The **get()** matrix function obtains a copy of an internal Stata system
matrix. Some system matrices can also be obtained more easily by
directly referring to the returned result after a command. In
particular, the coefficient vector can be referred to as **e(b)**, the
variance-covariance matrix of estimators as **e(V)**, and the constraints
matrix as **e(Cns)** after an estimation command.

See **mat_put_rr** for a programmer's command to directly post *matname* as the
internal **Rr** matrix.

__Remarks__

**get()** obtains copies of matrices containing coefficients and the
covariance matrix of the estimators after estimation commands (such as
**regress** and **probit**) and obtains copies of matrices left behind by other
Stata commands. The other side of **get()** is **ereturn post**, which allows
ado-file estimation commands to post results to Stata's internal areas;
see **[P] ereturn**.

__Examples__

**. sysuse auto**
**. regress price weight mpg**
**. matrix list e(b)**
**. matrix list e(V)**

**. matrix b = get(_b)**
**. matrix V = get(VCE)**
**. matrix list b**
**. matrix list V**

**. test weight=1, notest**
**. test mpg=40, accum**
**. matrix rxtr=get(Rr)**
**. matrix list rxtr**