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dsp.Minimum

Find minimum values of input or sequence of inputs

Description

The `dsp.Minimum` object finds the minimum value of an input or sequence of inputs.

Note

The `Running` mode in the `dsp.Minimum` System object™ will be removed in a future release. To compute the running minimum in MATLAB®, use the `dsp.MovingMinimum` System object instead.

To compute the minimum value of an input or sequence of inputs:

1. Create the `dsp.Minimum` object and set its properties.

2. Call the object with arguments, as if it were a function.

Creation

Syntax

``min = dsp.Minimum``
``min = dsp.Minimum(Name,Value)``

Description

example

````min = dsp.Minimum` returns an object, `min`, that computes the value and/or index of the minimum elements in an input or a sequence of inputs over the specified `Dimension`.```
````min = dsp.Minimum(Name,Value)` returns a minimum-finding object, `min`, with each specified property set to the specified value.```

Properties

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Unless otherwise indicated, properties are nontunable, which means you cannot change their values after calling the object. Objects lock when you call them, and the `release` function unlocks them.

If a property is tunable, you can change its value at any time.

Set this property to `true` in order to output the minimum value of the input. Set this property to `false` in order to output the index of the minimum value of the input.

Dependencies

This property applies only when you set the `RunningMinimum` property to `false`.

When you set this property to `true`, the object computes the minimum value over successive calls to the object algorithm. When you set this property to `false`, the object computes the minimum value over the current input.

Set this property to `true` to output the index of the minimum value of the input.

Dependencies

This property applies only when you set the `RunningMinimum` property to `false`.

Set this property to `true` to enable resetting of the running minimum. When you set this property to `true`, you must specify a reset input to the `step` method to reset the running minimum. This property applies only when you set the `RunningMinimum` property to `true`.

Specify the event that resets the running minimum. This property applies only when you set the ResetInputPort property to `true`.

Specify the numbering used when computing the index of the minimum value as starting from either `One` or `Zero`.

Dependencies

This property applies only when you set the `IndexOutputPort` property to `true`.

Specify how the minimum calculation is performed over the data.

Dependencies

This property applies when you set the `RunningMinimum` property to `false`.

Specify the integer dimension of the input signal over which the object finds the minimum. The cannot exceed the number of dimensions in the input signal.

Dependencies

This property only applies when you set the Dimension property to `Custom`.

Data Types: `single` | `double` | `int8` | `int16` | `int32` | `int64` | `uint8` | `uint16` | `uint32` | `uint64`

Fixed-Point Properties

Specify the rounding method.

Specify the overflow action.

Specify the product fixed-point data type.

Specify the product fixed-point type as a scaled `numerictype` object with a `Signedness` of `Auto`.

Dependencies

This property applies only when you set the `AccumulatorDataType` property to `Custom`.

Specify the accumulator fixed-point data type as one of | ```Same as product``` | `Same as input` | `Custom` |.

Specify the accumulator fixed-point type as a scaled `numerictype` object with a `Signedness` of `Auto`.

Dependencies

This property applies only when you set the `AccumulatorDataType` property to `Custom`.

Usage

For versions earlier than R2016b, use the `step` function to run the System object algorithm. The arguments to `step` are the object you created, followed by the arguments shown in this section.

For example, `y = step(obj,x)` and `y = obj(x)` perform equivalent operations.

Syntax

``[val,ind] = min(x)``
``val = min(x)``
``ind = min(x)``
``val = min(x,r)``

Description

example

````[val,ind] = min(x)` returns the minimum value, `val`, and the index or position of the minimum value, `ind`, along the specified `Dimension` of `x`.```
````val = min(x)` returns the minimum value, `val`, of the input `x`. When the `RunningMinimum` property is `true`, `val` corresponds to the minimum value over successive calls to the algorithm.```
````ind = min(x)` returns the zero- or one-based index `ind` of the minimum value when the `IndexOutputPort` property is `true` and the `ValueOutputPort` property is `false`. You must set the `RunningMinimum` property to `false` to use this syntax.```
````val = min(x,r)` resets the state of `min` based on the value of reset signal, `r`, and the `ResetCondition` property. To enable this type of processing, set the `RunningMinimum` property to `true` and the `ResetInputPort` property to `true`.```

Input Arguments

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Data input, specified as a vector or a matrix. If `x` is a matrix, each column is treated as an independent channel. The minimum is determined along each channel. The object also accepts variable-size inputs. Once the object is locked, you can change the size of each input channel.

Data Types: `single` | `double` | `int8` | `int16` | `int32` | `int64` | `uint8` | `uint16` | `uint32` | `uint64` | `fi`
Complex Number Support: Yes

Reset signal used to reset the running minimum, specified as a scalar value. The object resets the running minimum if the reset signal satisfies the `ResetCondition`.

Dependencies

To enable this signal, set the `RunningMinimum` property to `true` and the `ResetInputPort` property to `true`.

Data Types: `single` | `double` | `int8` | `int16` | `int32` | `uint8` | `uint16` | `uint32` | `logical`

Output Arguments

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Minimum value of the input, returned as a scalar or a vector. The object determines the minimum value of the input along each channel. If the input is a column vector, the output is a scalar. If the input is a multichannel signal, the output signal is a 1-by-N vector, where N is the number of input channels.

Data Types: `single` | `double` | `int8` | `int16` | `int32` | `int64` | `uint8` | `uint16` | `uint32` | `uint64` | `fi`
Complex Number Support: Yes

Indices of the minimum values of the input, returned as a scalar or a vector. The object determines the indices of the minimum values of the input along each channel. If the input is a column vector, the output is a scalar. If the input is a multichannel signal, the output signal is a 1-by-N vector, where N is the number of input channels.

Data Types: `double` | `uint32`

Object Functions

To use an object function, specify the System object as the first input argument. For example, to release system resources of a System object named `obj`, use this syntax:

`release(obj)`

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 `step` Run System object algorithm `release` Release resources and allow changes to System object property values and input characteristics `reset` Reset internal states of System object

Examples

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Note: This example runs only in R2016b or later. If you are using an earlier release, replace each call to the function with the equivalent `step` syntax. For example, myObject(x) becomes step(myObject,x).

Find a minimum value and its index.

``` min1 = dsp.Minimum; x = randn(100,1); [y, I] = min1(x) %#ok```
```y = -2.9443 ```
```I = 35 ```

Compute a running minimum.

``` min2 = dsp.Minimum; min2.RunningMinimum = true; x = randn(100,1); y = min2(x); plot(y);``` y(i) is the minimum of all values in the vector x(1:i).

Algorithms

This object implements the algorithm, inputs, and outputs described on the Minimum block reference page. The object properties correspond to the block parameters.