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### 4.4.3.3 Cartesian log axes

Due to the logarithmic nature of annotation spacings, the stride parameter takes on specific meanings. The following concerns are specific to log axes:

1. stride must be 1, 2, or 3. Annotations/ticks will then occur at 1, 1-2-5, or 1,2,3,4,...,9, respectively, for each magnitude range.

2. Append l to stride. Then, log of the annotation is plotted at every integer log value (e.g., will be annotated as ``2'') [Default annotates as is].

3. Append p to stride. Then, annotations appear as 10 raised to log of the value (e.g., ).

Figure 4.9: Logarithmic projection axis using separate values for annotation, frame, and grid intervals. (top) Here, we have chosen to annotate the actual values. Interval = 1 means every whole power of 10, 2 means 1, 2, 5 times powers of 10, and 3 means every 0.1 times powers of 10. We used -R1/1000/0/1 -JX3l/0.4 -Ba1f2g3. (middle) Here, we have chosen to annotate log of the actual values, with -Ba1f2g3l. (bottom) We annotate every power of 10 using log of the actual values as exponents, with -Ba1f2g3p.

Next: 4.4.3.4 Cartesian exponential axes Up: 4.4.3 Map frame and Previous: 4.4.3.2 Cartesian linear axes Contents Index