## Documentation Center |

You can use the **Continuous Wavelet 1-D (Using FFT)** tool
to analyze the same signals examined in DFT-Based Continuous Wavelet Analysis — Command Line.

At the MATLAB

^{®}command prompt, enterwavemenu

Click the

**Continuous Wavelet 1-D (Using FFT)**menu item.Choose the

**File > Load Data**option. When the**Pick a file**dialog appears, select`noisdopp.mat`from the`toolbox/wavelet/wavedemo`folder.Using the menu default parameters, click

**Analyze**.Reconstruct the signal based on all the default dyadic scales. Click

**Scales Selection**.Select all scales by clicking

**All**. Click**Synthesize**.In the top left, the synthesized signal plot is superimposed on the original signal. The relative maximum and L2 errors are displayed under the plot.

The single integral CWT inversion does not produce perfect reconstruction, but the relative errors using the default logarithmically–spaced scales are small.

Obtain a signal approximation from selected scales.

Click

**None**in the**Selection of Scales**panel to undo the scale selection. Then, select only scale indices greater than 10 and reconstruct an approximation to the original signal. Hold the`Ctrl`key while selecting scale indices 11–21. The scale indices correspond to the following physical scales.dt = 1; s0 = 2*dt; ds = 0.4875; nb = 21; physical_scales = s0*pow.^((0:nb-1)*ds);

Click

**Synthesize**.The reconstructed signal from scale indices 11–21 is a lowpass approximation to the noisy Doppler signal.

Analyze using linear scales. In the

**Scales**drop-down menu in the upper right, select`Linear default`and click**Analyze**.

Select coefficients manually by graphically selecting the CWT
coefficients. Reconstruct the signal from the selected coefficients.
Click **Manual Selection of Coefficients**. The **Select
the Coefficients Manually** panel appears with a single box
containing all the CWT coefficient moduli.

You can change the CWT coefficient view to `Angle`, `Real`,
or `Imaginary`.

To select a subset of coefficients, draw a box by left-clicking and dragging the mouse. When you release the mouse button, a semi-transparent box with a green border is superimposed on the plot.

You can place multiple boxes on the same plot. To synthesize
a signal based on the selected coefficients, click **Synthesize**.

To select, unselect, or delete a box, right-click in the box.
A context menu appears that allows you to **select**, **unselect**,
or **delete** the box. After you select the
coefficients within the box, the border of the box displays in green.
When the coefficients within the box are not selected, the border
of the box displays in red.

imYou can move a box by clicking the left mouse button inside
the box while simultaneously pressing the `Shift` key.
The border of the box changes to yellow, and you can drag the box
to the desired location. You must keep the `Shift` key
pressed while you are moving the box.

Quit the manual selection mode by clicking the **Close** button.

In the **Show synthesized signals from** panel
on the right, you can turn the plot of your synthesized signal on
and off by checking and unchecking **Manual selection**.

Using the **File > Save > Synthesized signal** menu,
you can save the available synthesized signals.

Using the **File > Save > Decomposition** menu,
you can save the wavelet analysis as a `MAT` file.

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