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docs/lib2-rand.md

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+# rand
+
+Random number generator. Generates a pseudo random number.
+
+## Parameters
+
+- `min_value` : Minimum value of random number range.
+- `max_value` : Maximum value of random number range.
+- `seed_value` : Optional. Seed value for random number generator for repeatable results. 
+
+## Examples
+
+    include <util/rand.scad>;
+    
+    echo(rand());              
+    echo(rand(1, 10));
+    echo(rand(seed_value = 4));    
+
+