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<p><b>New page</b></p><div>= Lab 5 =<br />
<br />
== Task 1 ==<br />
<br />
After fiddling around, I managed to get it to compile using MinGW on windows.<br />
What does the results mean? Who knows? LOL<br />
<br />
<pre><br />
gcc -o lab5 arraylist.c buzhash.c randtest.c lab-5.c<br />
</pre><br />
<br />
=== Results ===<br />
<br />
This is the first output I got.<br />
<pre><br />
Testing Buzhash low on 1000 samples<br />
Entropy = 7.843786 bits per byte.<br />
<br />
Optimum compression would reduce the size<br />
of this 1000 byte file by 1 percent.<br />
<br />
Chi square distribution for 1000 samples is 214.46, and randomly<br />
would exceed this value 95.00 percent of the times.<br />
<br />
Arithmetic mean value of data bytes is 128.0860 (127.5 = random).<br />
Monte Carlo value for Pi is 3.132530120 (error 0.29 percent).<br />
Serial correlation coefficient is -0.017268 (totally uncorrelated = 0.0).<br />
<br />
Buzhash low 50/1000: llps = 1, expecting 1.72187<br />
</pre><br />
<br />
Full Results (After removing verbose)<br />
<pre><br />
Test Name Entropy Chi Square Mean Monte Carlo Serial correlation coefficient<br />
----------------------------------------------------------------------------------------------------------------------------<br />
Low Entropies<br />
<br />
Buzhash low 7.98550 99.00% 125.825 1.26% -0.000047<br />
Buzhash N 7.98214 50.00% 127.589 2.10% 0.000600<br />
rt_add_hash_CRC 4.85247 0.01% 99.261 26.10% -0.285059<br />
rt_add_base256, 0.00000 0.01% 97.000 27.32% undefined<br />
rt_add_Java_Integer 4.11606 0.01% 32.385 27.32% -0.217081<br />
rt_add_Java_Object 2.00000 0.01% 77.000 27.32% -0.521556<br />
rt_add_Java_String 7.99463 99.99% 127.867 1.95% 0.009136<br />
rt_add_rand 4.86063 0.01% 47.740 27.32% -0.053147<br />
rt_add_high_rand 0.00000 0.01% 0.000 27.32% undefined<br />
<br />
<br />
Typical Entropies<br />
<br />
Buzhash low 7.97970 25.00% 127.177 1.95% -0.007153<br />
Buzhash N 7.98214 50.00% 127.589 2.10% 0.000600<br />
rt_add_hash_CRC 7.77880 0.01% 123.087 1.11% -0.002250<br />
rt_add_base256, 3.90309 0.01% 107.987 27.32% 0.079032<br />
rt_add_Java_Integer 4.11606 0.01% 2.385 27.32% -0.217081<br />
rt_add_Java_Object 5.18390 0.01% 107.202 9.67% -0.182027<br />
rt_add_Java_String 7.89301 0.01% 126.009 1.42% -0.021360<br />
rt_add_rand 4.86621 0.01% 48.035 27.32% -0.055499<br />
rt_add_high_rand 0.00000 0.01% 0.000 27.32% undefined<br />
</pre></div>
Mark