Created SC2072 (markdown)

SC2072.md

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+## Decimals are not supported. Either use integers only, or use bc or awk to compare.
+
+### Problematic code:
+
+    [[ 2 -lt 3.14 ]]
+
+### Correct code:
+
+    [[ 200 -lt 314 ]]                   # Use fixed point math
+    [[ $(echo "2 < 3.14" | bc) == 1 ]]  # Use bc
+
+### Rationale:
+
+Bash and Posix sh does not support decimals in numbers. Decimals should either be avoided, or compared using a tool that does support them.
+
+### Contraindications
+
+If the strings happen to be version numbers and you're using `<`, or `>` to compare them as strings, and you consider this an acceptable thing to do, then you can ignore this warning.