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MacBinary  |  1993-03-23  |  916.4 KB  |  [ONLN/HLX2]
open in: MacOS 8.1     |     Win98     |     DOS

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This file was processed as: MacBinary (archive/macBinary).

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10% dexvert MacBinary (archive/macBinary) fallback Supported
100% file MacBinary II, inited, Mon Mar 22 23:14:58 1993, modified Mon Mar 22 23:15:12 1993, creator 'HLX2', type 'ONLN', 932451 bytes "Color on 1-bit Devices" , at 0xe3ae3 5658 bytes resource default (weak)
99% file data default
100% TrID MacBinary 2 default (weak)
100% siegfried fmt/1762 MacBinary (II) default
100% lsar MacBinary default


id metadata
keyvalue
macFileType[ONLN]
macFileCreator[HLX2]


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|000061d0| 6f 66 20 34 35 fb 2e 20 | 41 74 20 30 fb 2c 20 74 |of 45.. |At 0., t|
|000061e0| 68 65 20 64 69 74 68 65 | 72 20 6d 61 74 72 69 78 |he dithe|r matrix|
|000061f0| 20 77 6f 75 6c 64 20 62 | 65 20 35 78 35 20 28 33 | would b|e 5x5 (3|
|00006200| 30 30 2f 36 30 29 2c 20 | 79 69 65 6c 64 69 6e 67 |00/60), |yielding|
|00006210| 20 32 36 20 70 6f 73 73 | 69 62 6c 65 20 73 68 61 | 26 poss|ible sha|
|00006220| 64 65 73 20 6f 66 20 67 | 72 61 79 2e 20 48 6f 77 |des of g|ray. How|
|00006230| 65 76 65 72 2c 20 61 73 | 20 46 69 67 75 72 65 20 |ever, as| Figure |
|00006240| 35 20 69 6c 6c 75 73 74 | 72 61 74 65 73 2c 20 77 |5 illust|rates, w|
|00006250| 65 20 6e 65 65 64 20 61 | 6e 20 38 78 38 20 6d 61 |e need a|n 8x8 ma|
|00006260| 74 72 69 78 20 74 6f 20 | 61 70 70 72 6f 78 69 6d |trix to |approxim|
|00006270| 61 74 65 20 74 68 65 20 | 64 65 73 69 72 65 64 20 |ate the |desired |
|00006280| 61 6e 67 6c 65 2e 20 54 | 68 65 73 65 20 64 69 6d |angle. T|hese dim|
|00006290| 65 6e 73 69 6f 6e 73 20 | 61 72 65 20 66 6f 75 6e |ensions |are foun|
|000062a0| 64 20 62 79 20 72 6f 74 | 61 74 69 6e 67 20 74 68 |d by rot|ating th|
|000062b0| 65 20 76 65 63 74 6f 72 | 73 20 28 30 2c 20 35 29 |e vector|s (0, 5)|
|000062c0| 20 61 6e 64 20 28 35 2c | 20 30 29 20 62 79 20 34 | and (5,| 0) by 4|
|000062d0| 35 fb 20 61 6e 64 20 70 | 69 6e 6e 69 6e 67 20 74 |5. and p|inning t|
|000062e0| 68 65 6d 20 74 6f 20 69 | 6e 74 65 67 65 72 73 2c |hem to i|ntegers,|
|000062f0| 20 79 69 65 6c 64 69 6e | 67 20 74 68 65 20 76 65 | yieldin|g the ve|
|00006300| 63 74 6f 72 73 20 28 34 | 2c 20 34 29 20 61 6e 64 |ctors (4|, 4) and|
|00006310| 20 0d 28 2d 34 2c 20 34 | 29 2e 20 53 69 6e 63 65 | .(-4, 4|). Since|
|00006320| 20 74 68 65 20 6d 61 67 | 6e 69 74 75 64 65 20 6f | the mag|nitude o|
|00006330| 66 20 74 68 65 20 76 65 | 63 74 6f 72 20 28 34 2c |f the ve|ctor (4,|
|00006340| 20 34 29 20 69 73 20 34 | 2a 73 71 72 74 28 32 29 | 4) is 4|*sqrt(2)|
|00006350| 2c 20 74 68 65 20 61 63 | 74 75 61 6c 20 68 61 6c |, the ac|tual hal|
|00006360| 66 74 6f 6e 65 20 66 72 | 65 71 75 65 6e 63 79 20 |ftone fr|equency |
|00006370| 61 63 68 69 65 76 65 64 | 20 77 69 6c 6c 20 62 65 |achieved| will be|
|00006380| 20 33 30 30 2f 28 34 2a | 73 71 72 74 28 32 29 29 | 300/(4*|sqrt(2))|
|00006390| 2c 20 61 72 6f 75 6e 64 | 20 35 33 2e 20 54 68 65 |, around| 53. The|
|000063a0| 20 65 72 72 6f 72 20 69 | 6e 20 66 72 65 71 75 65 | error i|n freque|
|000063b0| 6e 63 79 20 61 6e 64 20 | 61 6e 67 6c 65 20 69 73 |ncy and |angle is|
|000063c0| 20 64 75 65 20 74 6f 20 | 74 68 65 20 6e 65 65 64 | due to |the need|
|000063d0| 20 74 6f 20 70 69 6e 20 | 74 68 65 20 76 65 63 74 | to pin |the vect|
|000063e0| 6f 72 73 20 74 6f 20 69 | 6e 74 65 67 65 72 20 73 |ors to i|nteger s|
|000063f0| 70 61 63 65 2e 0d 48 65 | 72 65 d5 73 20 74 68 65 |pace..He|re.s the|
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