.. _analyze-line-label:

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Analyzing Linear Transects
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If the :ref:`quant-analysis-label` software is installed, selecting a line with the :ref:`line-inspector-label` activated will open the ``Line Inspector`` panel.  You will see a plot the amplitude and phase the intermodulation product corresponding to the image showing when the line was selected.  All data in each pixel along the transect line is selected for analysis with the :ref:`model-fit-label` method of force reconstruction.    

* The ``Line Inspector`` panel gives a list of all selected lines in the left column.  The color of the word ``line`` in the list corresponds to the color of the linear transect in the ``Amplitude`` and ``Phase`` images.

* Right-click on the word ``line`` and choose ``Fit model`` from the menue.  The currently active model will be fit to the intermodulation spectral data along the transect line, and a plot will be generated showing how each parameter of the model changes along the transect.  Depending on the length of the line and the speed of your computer, there may be some delay while the fitting is being performed at each pixel.

* You can automatically perform the fitting directly after the line is selected by checking the ``Fit model`` check box at the bottom of the list of lines.

* ``Settings`` will open the ``Line Inspector Settings`` panel where you can activated different force models, specify which parameters to adjust, and set the intial values of all parameters, as described in the :ref:`model-fit-label` section.

* You can test different models along the same linear transect:  Simply change the model in the ``Line Inspector Settings`` panel, then right-click on the word ``line`` and choose ``Fit Model``.  A fresh plot of the parameters of the new force model will be made along this line.  A new item is added to the list with each fit that your perform.   You can always go back to your previous plots by **double-clicking** on that item in the list.

* Right-click on any an item in the list and chose ``Save``  to export the results of that fit to a text file.  You can also save the plot image by clicking the save icon in the :ref:`image-toolbar-label`.  

* Right-click on any item and select ``Remove`` to take it away from the list.

* Click on the small triangles to expand and contract the list of fits for each line.

* Right-click on either the ``Amplitude`` or ``Phase`` image with the :ref:`line-inspector-label` activated to **remove** the line nearest to the right-click.