% Control System Toolbox -- Linear models.
%
% Model objects.
%   InputOutputModel - Overview of input/output model objects.
%   DynamicSystem    - Overview of dynamic system objects.
%   lti              - Overview of linear time-invariant system objects.
%   <a href="matlab:help InputOutputModel/get">get</a>              - Access properties of model object.
%   <a href="matlab:help InputOutputModel/set">set</a>              - Set/modify properties of model object.
%
% Numeric LTI models.
%   numlti           - Overview of numeric LTI models.
%   tf               - Create or convert to transfer function model.
%   filt             - Create digital filter.
%   zpk              - Create or convert to zero/pole/gain model.
%   ss               - Create or convert to state-space model.
%   dss              - Create descriptor state-space model.
%   rss              - Create random continuous-time state-space model.
%   drss             - Create random discrete-time state-space model.
%   sparss           - Sparse descriptor state-space model.
%   mechss           - Sparse second-order model.
%   pid              - Create 1-DOF PID controller in parallel form.
%   pid2             - Create 2-DOF PID controller in parallel form.
%   pidstd           - Create 1-DOF PID controller in standard form.
%   pidstd2          - Create 2-DOF PID controller in standard form.
%   frd              - Create or convert to frequency-response-data model.
%   chgFreqUnit      - Change frequency vector units in FRD model.
%
% Generalized LTI models.
%   genlti           - Overview of generalized LTI models.
%   ControlDesignBlock - Overview of special blocks for analysis/tuning.
%   AnalysisPoint    - Point of interest for analysis/tuning.
%   genmat           - Generalized matrix.
%   genss            - Generalized state-space model.
%   genfrd           - Generalized FRD model.
%   getValue         - Evaluate generalized model.
%   getBlockValue    - Get value of Control Design Block.
%   setBlockValue    - Modify value of Control Design Block.
%   showBlockValue   - Display Control Design Block values.
%   getPoints        - Get analysis point locations.
%   getLoopTransfer  - Compute open-loop transfer function.
%   getIOTransfer    - Compute closed-loop transfer function.
%   getSensitivity   - Compute sensitivity function.
%   getCompSensitivity - Compute complementary sensitivity function.
%   replaceBlock     - Replace block by value or by another block. 
%   sampleBlock      - Sample Control Design Blocks.
%   rsampleBlock     - Randomly sample Control Design Blocks.
%   
% Time delays.
%   tf/exp           - Create pure continuous-time delays.
%   delayss          - Create state-space models with delayed terms.
%   setDelayModel    - Specify internal delay model (state space only).
%   getDelayModel    - Access internal delay model (state space only).
%   <a href="matlab:help InputOutputModel/hasdelay">hasdelay</a>         - True for models with time delays.
%   totaldelay       - Total delay between each input/output pair.
%   absorbDelay      - Replace delays by poles at z=0 or phase shift.
%   pade             - Pade approximation of continuous-time delays.
%   thiran           - Thiran approximation of fractional delays.
%
% Arrays of models.
%   stack            - Stack models along some array dimension.
%   <a href="matlab:help InputOutputModel/nmodels">nmodels</a>          - Number of models in model array.
%   <a href="matlab:help InputOutputModel/nmodels">reshape</a>          - Reshape model array.
%   <a href="matlab:help InputOutputModel/nmodels">permute</a>          - Permute model array dimensions.
%   voidModel        - Mark missing or irrelevant models in model array.
%
% Data extraction.
%   tfdata           - Extract numerators and denominators.
%   zpkdata          - Extract zero/pole/gain data.
%   ssdata           - Extract state-space matrices.
%   dssdata          - Extract matrices of descriptor state-space model.
%   frdata           - Extract frequency response data.
%   piddata, piddata2        - Extract PID gains in parallel form.
%   pidstddata, pidstddata2  - Extract PID gains in standard form.
%
% Block diagram modeling.
%   append           - Aggregate models by appending inputs and outputs.
%   parallel         - Connect models in parallel.
%   series           - Connect models in series.
%   feedback         - Connect models with a feedback loop.
%   lft              - Generalized feedback interconnection.
%   connect          - Arbitrary block-diagram interconnection.
%   sumblk           - Specify summing junction (for use with CONNECT).
%   strseq           - Builds sequence of indexed strings (for I/O naming).
%
% Model transformation.
%   c2d              - Continuous to discrete conversion.
%   d2c              - Discrete to continuous conversion.
%   d2d              - Resample discrete-time model.
%   upsample         - Upsample discrete-time systems.
%   chgTimeUnit      - Change time units.
%   imp2exp          - Implicit to explicit conversion.
%   augstate         - Augment output by appending states.
%   ss2ss            - State coordinate transformation.
%   canon            - Canonical forms of state-space model.
%   prescale         - Optimal scaling of state-space model.
%   <a href="matlab:help ss/xperm">xperm</a>            - Reorder states in state-space model.
%
% Model simplification.
%   minreal          - Minimal realization and pole/zero cancellation.
%   sminreal         - Structurally minimal state-space realization.
%   balred           - Model order reduction via balanced truncation.
%   balreal          - Gramian-based balanced realization.
%   modred           - State elimination in balanced realization.
%   modelReducer     - Model reduction app.
%
% Model algebra.
%   <a href="matlab:help InputOutputModel/plus">+</a>, <a href="matlab:help InputOutputModel/minus">-</a>             - Add and subtract models (parallel connection).
%   <a href="matlab:help InputOutputModel/mtimes">*</a>                - Multiply models (series connection).
%   <a href="matlab:help InputOutputModel/mldivide">\</a>                - Left divide -- sys1\sys2 means inv(sys1)*sys2.
%   <a href="matlab:help InputOutputModel/mrdivide">/</a>                - Right divide -- sys1/sys2 means sys1*inv(sys2).
%   <a href="matlab:help InputOutputModel/mpower">^</a>                - Powers of a model.
%   <a href="matlab:help InputOutputModel/transpose">.'</a>               - Transposition of input/output map.
%   <a href="matlab:help InputOutputModel/ctranspose">'</a>                - Pertranspose H(s) to H(-s).' or H(z) to H(1/z).'
%   <a href="matlab:help DynamicSystem/times">.*</a>               - Element-by-element multiplication.
%   <a href="matlab:help InputOutputModel/horzcat">[,]</a>, <a href="matlab:help InputOutputModel/vertcat">[;]</a>         - Concatenate models along inputs or outputs.
%   <a href="matlab:help InputOutputModel/inv">inv</a>              - Inverse of input/output model.
%   <a href="matlab:help InputOutputModel/conj">conj</a>             - Complex conjugation of model coefficients.
%   frd/fcat         - Merge frequency responses.
%   frd/fselect      - Select frequency range or frequency points.
%   frd/abs          - Entrywise magnitude of the frequency response.
%   frd/real         - Real part of the frequency response.
%   frd/imag         - Imaginary part of the frequency response.
%   frd/interp       - Interpolate frequency response data.

%   Copyright 1986-2015 The MathWorks, Inc.




