- Function File:
`sys`=**ss**(`sys`) - Function File:
`sys`=**ss**(`d, ...`) - Function File:
`sys`=**ss**(`a, b, ...`) - Function File:
`sys`=**ss**(`a, b, c, ...`) - Function File:
`sys`=**ss**(`a, b, c, d, ...`) - Function File:
`sys`=**ss**(`a, b, c, d, tsam, ...`) Create or convert to state-space model.

**Inputs**`sys`- LTI model to be converted to state-space.
`a`- State matrix (n-by-n).
`b`- Input matrix (n-by-m).
`c`- Output matrix (p-by-n).
If
`c`is empty`[]`

or not specified, an identity matrix is assumed. `d`- Feedthrough matrix (p-by-m).
If
`d`is empty`[]`

or not specified, a zero matrix is assumed. `tsam`- Sampling time in seconds. If
`tsam`is not specified, a continuous-time model is assumed. `...`- Optional pairs of properties and values.
Type
`set (ss)`for more information.

**Outputs**`sys`- State-space model.

**Option Keys and Values**`'a', 'b', 'c', 'd', 'e'`- State-space matrices. See 'Inputs' for details.
`'stname'`- The name of the states in
`sys`. Cell vector containing strings for each state. Default names are`{'x1', 'x2', ...}`

`'scaled'`- Logical. If set to true, no automatic scaling is used,
e.g. for frequency response plots.
`'tsam'`- Sampling time. See 'Inputs' for details.
`'inname'`- The name of the input channels in
`sys`. Cell vector of length m containing strings. Default names are`{'u1', 'u2', ...}`

`'outname'`- The name of the output channels in
`sys`. Cell vector of length p containing strings. Default names are`{'y1', 'y2', ...}`

`'ingroup'`- Struct with input group names as field names and
vectors of input indices as field values.
Default is an empty struct.
`'outgroup'`- Struct with output group names as field names and
vectors of output indices as field values.
Default is an empty struct.
`'name'`- String containing the name of the model.
`'notes'`- String or cell of string containing comments.
`'userdata'`- Any data type.

**Equations**. x = A x + B u y = C x + D u

**Example**octave:1> a = [1 2 3; 4 5 6; 7 8 9]; octave:2> b = [10; 11; 12]; octave:3> stname = {'V', 'A', 'kJ'}; octave:4> sys = ss (a, b, 'stname', stname)

sys.a = V A kJ V 1 2 3 A 4 5 6 kJ 7 8 9

sys.b = u1 V 10 A 11 kJ 12

sys.c = V A kJ y1 1 0 0 y2 0 1 0 y3 0 0 1

sys.d = u1 y1 0 y2 0 y3 0 Continuous-time model. octave:5>

**See also:**tf, dss.

Package: control