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+Scripts that Generate Graphs
+============================
+
+This directory contains scripts that generate graphs. Each script is run with
+bash and may require additional tools. All of the scripts require gnuplot.
+
+All scripts produce a PNG graph on stdout and the data on stderr.
+
+Test Runs by category
+---------------------
+
+The script `categorize-tests.bash`, and its associated awk and plot scripts,
+generate a stacked bar chart with bars representing groups of tests (l1 l2,
+etc.) and segments of the bars representing types. `categorize-tests.bash`
+accepts an argument to filter the tests included with grep.
+
+For example, the following will produce a graph of the juno-specific tests:
+
+    bash categorize-tests.bash juno > juno-tests.png 2> juno-tests.txt
+
+*Copyright (c) 2021, Arm Limited. All rights reserved.*