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#76 2010-06-24 12:07:42

Sperry
Scratcher
Registered: 2010-03-09
Posts: 500+

Re: Trigonometry Help

Rather off-topic here, but since this is a trig thread, I'd just like to ask if anyone could teach me or find me a good tutorial about trig. I think it is soo useful and brilliant but I just cant find anywhere to learn it from. Also, I'm not going to learn it at school for another year, and I dont want to wait that long.


http://img709.imageshack.us/img709/3252/gobanim2.gifhttp://ls.gd/bo

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#77 2010-06-25 09:04:05

1stCorinthians
Scratcher
Registered: 2009-06-14
Posts: 52

Re: Trigonometry Help

Alrighty.

Um, It's gonna be very hard to explain. Why dont i put it in a project for you so you can see it and confirm if I did the correct thing?

Oh geez this is hard

Last edited by 1stCorinthians (2010-06-25 10:21:41)

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#78 2010-06-25 13:13:01

Sperry
Scratcher
Registered: 2010-03-09
Posts: 500+

Re: Trigonometry Help

1stCorinthians wrote:

Alrighty.

Um, It's gonna be very hard to explain. Why dont i put it in a project for you so you can see it and confirm if I did the correct thing?

Oh geez this is hard

Sure! Any help would be great, I really appreciate it.


http://img709.imageshack.us/img709/3252/gobanim2.gifhttp://ls.gd/bo

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#79 2010-06-25 16:33:30

billyedward
Scratcher
Registered: 2008-01-03
Posts: 500+

Re: Trigonometry Help

nXIII wrote:

billyedward wrote:

Ok, I fixed it.
Here is the XML code for the working block:

Code:

<?xml version="1.0" encoding="UTF-8" ?><scratchScript><block selector="-"><argument><block selector="+"><argument>-90</argument><argument><block selector="*"><argument>90</argument><argument><block selector="*"><argument><block selector="-"><argument><block selector="computeFunction:of:"><argument>abs</argument><argument><block selector="-"><argument><block selector="\\"><argument><block selector="+"><argument><block selector="rounded"><argument><block selector="computeFunction:of:"><argument>10 ^</argument><argument><block selector="+"><argument><block selector="-"><argument><block selector="mouseX"/></argument><argument><block selector="xpos"/></argument></block></argument><argument>15</argument></block></argument></block></argument></block></argument><argument>0.5</argument></block></argument><argument>2</argument></block></argument><argument>1</argument></block></argument></block></argument><argument>0.5</argument></block></argument><argument>4</argument></block></argument></block></argument></block></argument><argument><block selector="computeFunction:of:"><argument>atan</argument><argument><block selector="dividedBy"><argument><block selector="-"><argument><block selector="ypos"/></argument><argument><block selector="mouseY"/></argument></block></argument><argument><block selector="+"><argument><block selector="-"><argument><block selector="xpos"/></argument><argument><block selector="mouseX"/></argument></block></argument><argument>1.0e-14</argument></block></argument></block></argument></block></argument></block></scratchScript>

It is a MASSIVE binomial.
The second term is basically the above, with 0.0000000000001 added to the denominator to avoid division by zero.

The first is a LONG, but foolproof mathematical way of taking any number, and returning it's sign. I need this, as TAN cannot distinguish between positive and negative angles, as all slopes (the argument) are bidirectional. So I need to do that conversion myself, via this first term. I just came up with this now, but if anyone else has a simpler mathematical way of deducing the sign of a number, please tell me.

I don't really know what this looks like, but you should probably look at my five-ish-line approach. It's simple, but 100% effective (or is it affective? Ugh, I always remember these things, but now I forget!).

I just remember that effect is a noun, and affect is a verb.
So effective means 'causes desired effects.'
As the root of the word is the noun form, it is spelled with an e.


"I'd love to change the world, but they haven't released the source code yet."
Check out the latest version of Streak --> http://billy.scienceontheweb.net/Streak

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#80 2010-06-25 16:47:55

billyedward
Scratcher
Registered: 2008-01-03
Posts: 500+

Re: Trigonometry Help

Sperry wrote:

1stCorinthians wrote:

Alrighty.

Um, It's gonna be very hard to explain. Why dont i put it in a project for you so you can see it and confirm if I did the correct thing?

Oh geez this is hard

Sure! Any help would be great, I really appreciate it.

Just wondering...
Do you or your username have any affiliation to the Sperry computer company?


"I'd love to change the world, but they haven't released the source code yet."
Check out the latest version of Streak --> http://billy.scienceontheweb.net/Streak

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#81 2010-06-26 05:09:42

Sperry
Scratcher
Registered: 2010-03-09
Posts: 500+

Re: Trigonometry Help

billyedward wrote:

Sperry wrote:

1stCorinthians wrote:

Alrighty.

Um, It's gonna be very hard to explain. Why dont i put it in a project for you so you can see it and confirm if I did the correct thing?

Oh geez this is hard

Sure! Any help would be great, I really appreciate it.

Just wondering...
Do you or your username have any affiliation to the Sperry computer company?

No. 0_o Never heard of it. The name is just one of my many nicknames I have.


http://img709.imageshack.us/img709/3252/gobanim2.gifhttp://ls.gd/bo

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#82 2010-06-28 09:41:52

bharvey
Scratcher
Registered: 2008-08-10
Posts: 1000+

Re: Trigonometry Help


http://cs.berkeley.edu/~bh/sig5.png

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#83 2010-06-28 09:49:30

bharvey
Scratcher
Registered: 2008-08-10
Posts: 1000+

Re: Trigonometry Help

billyedward wrote:

I just remember that effect is a noun, and affect is a verb.

It's more complicated than that, actually.

EFFECT (noun): the result of an action or process;
influence on something/someone.  "Scratch has had a large effect on my programming style."

EFFECT (verb): to cause to happen, to bring about.  "We'd like to effect an expansion of the Scratch audience to older learners."

AFFECT (noun): emotion, or a show of emotion.  "The shock victim showed little affect despite the grisly scene."

AFFECT (verb): to change something/someone.  "An overemphasis on testing affects how teachers teach."

It's true that most of the time what people mean is the noun version of "effect" and the verb version of "affect," except for lawyers and politicians, who use "effect" as a verb, and psychotherapists, who use "affect" as a noun.  smile


http://cs.berkeley.edu/~bh/sig5.png

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#84 2011-01-21 15:46:40

legomany3448
Scratcher
Registered: 2010-08-30
Posts: 36

Re: Trigonometry Help

Easy.  Make an invisible (hiding) sprite at the center, and tell it to point to the mouse pointer!  Use the [blocks] <direction> block to get the direction.  wink


¿uʍop-ǝpısdn pɐǝɹ noʎ uɐɔ
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#85 2011-01-21 15:51:22

LS97
Scratcher
Registered: 2009-06-14
Posts: 1000+

Re: Trigonometry Help

legomany3448 wrote:

Easy.  Make an invisible (hiding) sprite at the center, and tell it to point to the mouse pointer!  Use the [blocks] <direction> block to get the direction.  wink

You do realize that this thread is very old and has about 4 pages of answers, and that you just bumped it up by about half a year, don't you?

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#86 2011-01-21 16:14:05

ProgrammingFreak
Scratcher
Registered: 2010-09-04
Posts: 1000+

Re: Trigonometry Help

LS97, check your comments...

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#87 2011-01-21 16:43:37

LS97
Scratcher
Registered: 2009-06-14
Posts: 1000+

Re: Trigonometry Help

ProgrammingFreak wrote:

LS97, check your comments...

Hey, hey, I do!
It's late here though so I'm going to sleep.
And, I don't know how much other people appreciate private conversations on a thread by someone else, very old, lately bumped, and with 4 pages  hmm  Next time, the comment will be more than enough.  wink

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#88 2011-01-21 17:19:32

shadow_7283
Scratcher
Registered: 2007-11-07
Posts: 1000+

Re: Trigonometry Help

Yep, this problem has been resolved (that or I just forgot about it).  tongue  Posting stops now.

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#89 2011-06-22 05:55:03

poemon1
Scratcher
Registered: 2011-01-12
Posts: 500+

Re: Trigonometry Help

can someone please post a tut on how to use the trigonometry functions?


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#90 2011-06-22 11:04:53

shadow_7283
Scratcher
Registered: 2007-11-07
Posts: 1000+

Re: Trigonometry Help

Create your own thread. Please don't bump up this one.  smile

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#91 2011-06-22 15:29:02

14God
Scratcher
Registered: 2008-11-14
Posts: 100+

Re: Trigonometry Help

I believe this is an efficient way to find the direction to an object:
https://sites.google.com/site/byobimages/_/rsrc/1308770842071/helpful/helpful.bmp

Last edited by 14God (2011-06-22 15:29:31)


http://cs.berkeley.edu/~bh/sig4.png
Logic and reason have led me to atheism... but I'm stuck with the name  tongue

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