base:ax_tinyrand8
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| Both sides previous revisionPrevious revision | Last revisionBoth sides next revision | ||
| base:ax_tinyrand8 [2021-11-28 00:00] – added plot wil | base:ax_tinyrand8 [2021-11-28 03:25] – seeding function further explained wil | ||
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| This version stores the seed as arguments and uses self-modifying code and requires only 15 bytes for the random function. The execution time is constant at 18 cycles and much faster than for example a 789-Xorshift. | This version stores the seed as arguments and uses self-modifying code and requires only 15 bytes for the random function. The execution time is constant at 18 cycles and much faster than for example a 789-Xorshift. | ||
| - | The seeding function was tricky, since putting any two values into b1 and c1 comes with a 10% risk of ending up in a cycle with shorter period. Therefore, a seeding function is provided that takes an 8 bit values and generates a seed that is guaranteed to be in cycle with a period of 59748. | + | The seeding function was tricky, since putting any two values into b1 and c1 comes with a 10% risk of ending up in a cycle with shorter period. Therefore, a seeding function is provided that takes an 8 bit values and generates a seed that is guaranteed to be in cycle with a period of 59748. However, there are only 64 different states reachable after seeding. |
| In a test, I plotted the output of 51200 random values, which don't seem to reveal any visible patterns: | In a test, I plotted the output of 51200 random values, which don't seem to reveal any visible patterns: | ||
base/ax_tinyrand8.txt · Last modified: 2021-11-29 00:12 by wil