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Unread 12-07-2011, 15:40
davidthefat davidthefat is offline
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Re: Cartesian to angle

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Originally Posted by AdamHeard View Post
Why? That's terribly cumbersome compared to the methods already posted.
Well, it takes less clock cycles to just retrieve data from an array compared to calculating the angle on the fly. Even though a look up table does take up considerable amount of space in the RAM (Not really since we are dealing with 64 MB of RAM...) Also given the level of accuracy we only really need, about ± pi/180 radian. I think it should be fine.
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Unread 12-07-2011, 16:04
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Re: Cartesian to angle

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Originally Posted by davidthefat View Post
Well, it takes less clock cycles to just retrieve data from an array compared to calculating the angle on the fly. Even though a look up table does take up considerable amount of space in the RAM (Not really since we are dealing with 64 MB of RAM...) Also given the level of accuracy we only really need, about ± pi/180 radian. I think it should be fine.
The cycles are a nonissue on the cRIO, and using the function is substantially less code/setup time.
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Unread 12-07-2011, 16:11
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Re: Cartesian to angle

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Originally Posted by davidthefat View Post
Well, it takes less clock cycles to just retrieve data from an array compared to calculating the angle on the fly.
Where do you get your information ?


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Unread 12-07-2011, 16:27
EricVanWyk EricVanWyk is offline
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Re: Cartesian to angle

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Originally Posted by Ether View Post

Where do you get your information ?

You must spread some Reputation around before giving it to Ether again.
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Unread 14-07-2011, 12:05
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Re: Cartesian to angle

Quote:
Originally Posted by davidthefat View Post
Well, it takes less clock cycles to just retrieve data from an array compared to calculating the angle on the fly. Even though a look up table does take up considerable amount of space in the RAM (Not really since we are dealing with 64 MB of RAM...) Also given the level of accuracy we only really need, about ± pi/180 radian. I think it should be fine.
Wait, the crio only has 64 MB of ram? Yes, it does indeed. You learn something new every day I guess.
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Unread 14-07-2011, 14:18
jhersh jhersh is offline
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Re: Cartesian to angle

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Originally Posted by PAR_WIG1350 View Post
Wait, the crio only has 64 MB of ram? Yes, it does indeed. You learn something new every day I guess.
... and the new cRIO-FRC2 has 128 MB of RAM.
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