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README.md

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-# pert
-A simple utility to estimate tasks using PERT
+### Bash PERT Calculator
+
+A simple utility to estimate tasks using PERT (Program evaluation and review technique)
+
+### Usage
+<pre>
+A command line PERT calculator for quick estimates.
+
+Comma separated task list in the form "1,2,12 4,5,9 2,3,6", where whitespace separates tasks.
+
+Usage:
+	pert [optimistic,realistic,pessimistic]
+
+Example:
+	pert 1,3,4
+	pert 10,15,20 5,7,10
+	pert "1,2,3" "15,17,20"
+</pre>
+
+### Example
+
+Command:
+
+`$ ./pert.sh 5,7,10 2,3,4 10,12,14`
+
+Output:
+<pre>
+Tasks
+
+ +--------------------------------------------------------------------------------------+
+ | #            | optimistic | realistic | pessimistic | duration |     risk | variance |
+ +--------------------------------------------------------------------------------------+
+ | 1. task      |          5 |         7 |          10 |     7.16 |     0.83 |     0.68 |
+ | 2. task      |          2 |         3 |           4 |     3.00 |     0.33 |     0.10 |
+ | 3. task      |         10 |        12 |          14 |    12.00 |     0.66 |     0.43 |
+ +--------------------------------------------------------------------------------------+
+ | summary      |          - |         - |           - |    22.16 |     1.82 |     1.21 |
+ +--------------------------------------------------------------------------------------+
+
+Three point estimates
+
+ +----------------------------------------+
+ | confidence    |            |           |
+ +----------------------------------------+
+ | 1 Sigma - 68% |      20.95 |     23.37 |
+ | 1 Sigma - 95% |      19.74 |     24.58 |
+ | 1 Sigma - 99% |      18.53 |     25.79 |
+ +----------------------------------------+
+ </pre>