Maths (Arithmetic): log

       Name: log                                                     [Show more]
       Type: Variable
   Category: Maths (Arithmetic)
    Summary: Binary logarithm table (high byte)
    Context: See this variable in context in the source code
 References: This variable is used as follows:
             * DVID4 uses log
             * FMLTU uses log
             * LL28 uses log
             * LOIN (Part 2 of 7) uses log
             * LOIN (Part 5 of 7) uses log


 At byte n, the table contains the high byte of:

   $2000 * log10(n) / log10(2) = 32 * 256 * log10(n) / log10(2)

 where log10 is the logarithm to base 10. The change-of-base formula says that:

   log2(n) = log10(n) / log10(2)

 so byte n contains the high byte of:

   32 * log2(n) * 256


.log

 SKIP 1

 FOR I%, 1, 255

  EQUB HI(INT($2000 * LOG(I%) / LOG(2) + 0.5))

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