# 21.2 NetCDF Manipulating

## Manipulation on Matrix Data

After importing a NetCDF file into matrix stack, you can performmanipulation on matrix data.

The following examples show how to use these tools on NetCDF data.

#### Linear Fit on Matrix Stack

Select Analysis: Linear Fit on Matrix Stack to open the dialog, perform a linear fit on the NetCDF matrix stack. #### Descriptive Statistics on Matrix

Select Analysis: Descriptive Statistics to open the dialog to get the descriptive statistics (Mean, SD, Min, Max, Median and Sum) for the matrix stack. #### Subtraction

Select Analysis: Mathematics: Subtract to open the dialog, perform subtraction between two same-sized matrice stacks to get the difference between them.

In the following illustration, we'll get the mean value of the matrix from and then perform subtraction with two mean value matrices to get the difference of them. #### Pixel Extraction

Select Matrix: Pixel Extraction to open the dialog, extract the Z value for specified XY coordinates for all matrices in the matrix stack.

To specified XY coordinate values, you can:

or

• Manually specify longitude and latitude values in the dialog.

or

• Specify longitude and latitude by reference columns. Then extract z values for multiple XY coordinate pairs all at once.
Note: You can use the longitude and latitude dataset from shapefiles imported by Import Shapefile App ## Profiling Matrix Data on ROI

When a matrix is in Image Mode, you can use first select an area using the Rectangle/ Circle/ Polygon/ Region tool as region-of-interest (ROI), and then extract data from it.

Right-click on the ROI and choose an option from the shortcut menu. To discard the ROI, press Delete. Each ROI is added with a default name (e.g. ROI). You can add multiple ROIs to your matrix image but you need to rename each ROI before you can add another. 1. Double-click on the ROI to open the ROI Position dialog box.
2. Give the ROI a meaningful (unique) name and click OK.

#### Copy and Paste Positions

Copy the position of the selected ROI. Then paste the position of the selected ROI to another ROI (width, height...all). #### Export and Import ROI

Save the ROI object(s).
Replace the object(s) with those in a saved .ROI file (hint: create a "dummy" ROI to import). #### Create ROI from XY

Add ROI on the matrix, right-click on the ROI in the Matrix, select Create ROI from XY, and use xy2roi tool to import the Worksheet XY data for defining the ROI.

For example, there is a dataset from shapefiles, you can import it into the NetCDF matrix. #### Create New

Use the mroi2mat tool to generate a new matrix from the ROI. #### Extract as XYZ

Use the mroi2xyz tool to generate a new worksheet of XYZ values in the ROI.

#### Intensity Profile

Use the mroiprofile tool to generate the descriptive statistics value (Mean, SD, Min, Max, Median and Sum) for the ROI.

For example, after add a shapefiles dataset as the ROI (Create ROI from XY tool), you can use use Intensity Profile tool to analysis the ROI dataset. 