2002-01-07 15:25:25 +00:00
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#!/bin/bash
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2012-11-27 14:56:18 +00:00
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# random2.sh: Returns a pseudorandom number in the range 0 - 1,
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#+ to 6 decimal places. For example: 0.822725
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# Uses the awk rand() function.
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2002-01-07 15:25:25 +00:00
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AWKSCRIPT=' { srand(); print rand() } '
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2012-11-27 14:56:18 +00:00
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# Command(s)/parameters passed to awk
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2002-01-07 15:25:25 +00:00
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# Note that srand() reseeds awk's random number generator.
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2003-11-03 16:25:16 +00:00
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2002-01-07 15:25:25 +00:00
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echo -n "Random number between 0 and 1 = "
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2003-11-03 16:25:16 +00:00
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2002-01-07 15:25:25 +00:00
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echo | awk "$AWKSCRIPT"
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2003-11-03 16:25:16 +00:00
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# What happens if you leave out the 'echo'?
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2002-01-07 15:25:25 +00:00
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exit 0
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2002-04-01 16:04:17 +00:00
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# Exercises:
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# ---------
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2002-01-07 15:25:25 +00:00
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2002-04-01 16:04:17 +00:00
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# 1) Using a loop construct, print out 10 different random numbers.
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2012-11-27 14:56:18 +00:00
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# (Hint: you must reseed the srand() function with a different seed
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#+ in each pass through the loop. What happens if you omit this?)
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2002-01-07 15:25:25 +00:00
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2002-04-01 16:04:17 +00:00
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# 2) Using an integer multiplier as a scaling factor, generate random numbers
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2012-11-27 14:56:18 +00:00
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#+ in the range of 10 to 100.
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2002-01-07 15:25:25 +00:00
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2002-04-01 16:04:17 +00:00
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# 3) Same as exercise #2, above, but generate random integers this time.
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