Toolbox | Microarray Analysis ()| Transformation and Normalization | Transform ()
Select a number of samples ( () or ()) or an experiment () and click Next.
This will display a dialog as shown in figure 31.20.
At the top, you can select which values to transform (see Selecting transformed and normalized values for analysis).
Next, you can choose three kinds of transformation:
- Logarithm transformation. Transformed expression values will be calculated by taking the logarithm (of the specified type) of the values you have chosen to transform.
- Natural logarithm.
- Adding a constant. Transformed expression values will be calculated by adding the specified constant to the values you have chosen to transform.
- Square root transformation.
Click Finish to start the tool.