Where is the Basic of Math? ArcCos, Exponent and else? Can you give me some Link ? :alright: Thanks
Posted on 2003-08-27 09:13:42 by realvampire

Where is the Basic of Math? ArcCos, Exponent and else? Can you give me some Link ? :alright: Thanks

School is one place, Dr.Math (google for it) is another (I think thay have some inbfo about it and much more advanced math).
Posted on 2003-08-27 09:44:41 by scientica
But I hate School. I more like study at home.
Posted on 2003-08-27 09:52:31 by realvampire

But I hate School.

I did hate school Posted on 2003-08-27 10:11:22 by scientica
Yes, some times the school isnot a good place to study :), but some times is, that 'depend' on a lot of factors, like the teachers, the 'carrera', the friends and suchs things.


Sure the house is a good place to study, there you have normally all what you need, except for the 'biblioteca', and there you dont have the social interaction with the friend or teachers.


I think that you can make a place confortable to study if you want, only watch what do you want in a place to study and try adapt, in the case that you cant adapt that place.... try to be ok whit what is there.

I remember some time a go that dosent matter where you go to study, the matter is that you go for study. And you can study elsewhere. Including imagination for have a pencil, or have 'artifacts' like a sphere a triangle and a plane intersecting in a specific point moving trought a parabolic path. :D



I recomend that try do a (i dont know how to say) large scratch page "pizarr?n"->blackboard, with erasable pencils and do some work there like you are the teacher for your self ;).



For where to find books on math, you can search for free books, or e-books or handbooks on math, also you can find some ones in programms that normally are used for download music :P

The other good option are the "bibliotecas".





I think you need that some subjects like... if the teacher dont make how you can see the good things in a subject, then search yourself wht you like of the subject, ie, in the past course the teacher of 'discrete maths' only show to us like 50% or less of the total course and the major part of the group only take that i later need see what was all the course and I see that the complete course was a very good thing, but the teacher dont show all... then I have 2 choices: read a complete book on discrete maths or reenter (like a listener) to a class on discrete math, and the choice was the third.... the third??.. not was only 2???... yes the third, the mix of the first two, reenter to the class and read a complete book... maybe more than one ;).

Now with that posibility of teachers... I am trying to see for my part the complete course, and in this way dosent matter that the teacher dont show all the course, I can now all the course by my self, I only need the tools ans a little interaction with the others ideas.

Nice day.
Posted on 2003-08-27 10:33:29 by rea
Anyone know how to made and use ArcCos ?:confused:




SlowGetDegree proc ; x,y,x2,y2
; Brute Forcing the Degree

pop [ebp+#16] ; EIP

pop [ebp+#12] ; y2
pop [ebp+#8] ; x2
pop [ebp+#4] ; y
pop [ebp] ; x

push [ebp+#16] ; EIP

push ebp
push [ebp]
push [ebp+#4]
push [ebp+#8]
push [ebp+#12]
add ebp,#128
call getDeltaXY
pop ebp

mov [ebp+#16],edx
mov [ebp+#20],eax

push ebp
push [ebp+#16]
push [ebp+#20]
add ebp,#128
call GetHypotenusa
pop ebp

mov [ebp+#24],eax ; Hypotenusa

mov ecx,#900
@@f
push ecx

push ebp
push ecx
push [ebp] ; x
push [ebp+#24] ; Hyp
push ecx ; Rotation
add ebp,#100 ;
call HitX ;
pop ecx
pop ebp
;add eax,[ebp] ;
mov [ebp+#28],eax
mov [ebp+#32],edx

push ebp
push ecx
push [ebp+#4] ; y
push [ebp+#24] ; HYp
push ecx ; Rotation
add ebp,#100 ;
call HitY ;
pop ecx
pop ebp
mov [ebp+#36],eax
mov [ebp+#40],edx

mov eax,[ebp+#8] ; x2
cmp eax,[ebp+#28] ; compare with +X
jnz SGD_quad_2 ;
mov eax,[ebp+#12] ; y2
cmp eax,[ebp+#36] ; Compare with +Y
jnz SGD_quad_2 ;
pop ecx
mov eax,ecx ; Degree
ret
SGD_quad_2 data
mov eax,[ebp+#8] ; x2
cmp eax,[ebp+#28] ; compare with +X
jnz SGD_quad_3 ;
mov eax,[ebp+#12] ; y2
cmp eax,[ebp+#40] ; Compare with -Y
jnz SGD_quad_3 ;
pop ecx
mov eax,ecx ; Degree
add eax,#900 ; add with 90.0 degrees
ret
SGD_quad_3 data
mov eax,[ebp+#8] ; x2
cmp eax,[ebp+#32] ; compare with -X
jnz SGD_quad_4 ;
mov eax,[ebp+#12] ; y2
cmp eax,[ebp+#40] ; Compare with -Y
jnz SGD_quad_4 ;
pop ecx
mov eax,ecx ; Degree
add eax,#1800 ; add with 180.0 degrees
ret
SGD_quad_4 data
mov eax,[ebp+#8] ; x2
cmp eax,[ebp+#32] ; compare with -X
jnz SGD_quad_brs ;
mov eax,[ebp+#12] ; y2
cmp eax,[ebp+#40] ; Compare with -Y
jnz SGD_quad_brs ;
pop ecx
mov eax,ecx ; Degree
add eax,#2700 ; add with 270.0 degrees
ret
SGD_quad_brs data
pop ecx
dec ecx
jnz @@f

xor eax,eax ; Failed
dec eax ; Eax =-1
ret
SlowGetDegree endp




Here is my algol. It so Slooow, and sometime Failed.
Posted on 2003-08-29 05:39:05 by realvampire
x1 - x2 = a
y1 - y2 = b

tan angle
= opp/adj
= b/a
basic angle = tan^-1 |b/a|

If b/a = positive, angle = basic angle or 180 degrees + basic angle
If b/a = negative, angle = 180 degrees - basic angle or 360 degrees - basic angle
Posted on 2003-08-29 05:53:10 by roticv

x1 - x2 = a
y1 - y2 = b

tan angle
= opp/adj
= b/a
basic angle = tan^-1 |b/a|

If b/a = positive, angle = basic angle or 180 degrees + basic angle
If b/a = negative, angle = 180 degrees - basic angle or 360 degrees - basic angle


is tan^-1 are aTan?(FPATAN).
Posted on 2003-08-29 05:59:48 by realvampire
*flip flip*

Yes indeed. Arctan = inverse tan
http://functions.wolfram.com/ElementaryFunctions/ArcTan/
Posted on 2003-08-29 06:04:14 by roticv
realvampire

You may get some useful info from the description of the FPTAN instruction in the Simply FPU tutorial. See:

http://www.masmforum.com/website/tutorials/fptute/fpuchap10.htm#fpatan

Just ask if you need more info.

Raymond
Posted on 2003-08-29 10:17:04 by Raymond
Thank you raymond.
I want to know ArcCos, more Completely. Or maybe you have it function to share ?
Posted on 2003-08-29 11:09:33 by realvampire
Arccos is the inverse of the f(x) = cos x.
I suppose you know that cos x = adj/hypo

Maybe this link will interest you.
http://mathforum.org/dr.math/faq/formulas/faq.trig.html
Posted on 2003-08-29 11:18:01 by roticv
I wrote alot of macros you can use them almost as if they were FPU instructions
Posted on 2003-08-29 12:19:19 by Eóin
realvampire

The link I gave you has the code to compute the ArcSin using the FPATAN instruction. It also describes how to modify that code to compute the ArcCos and what you can expect from the result. If there is something you don't understand, I will be glad to provide more info.

Raymond
Posted on 2003-08-29 13:40:06 by Raymond
Yeah, great. I didnot saw it ( I forgot to use my Glass, the letter are so Small. Sorry). I'll study it right now. Thanks:alright:




;ST(0)=sin(x), ST(1)=zzz
fld st ;ST(0)=sin(x), ST(1)=sin(x), ST(2)=zzz
fmul st,st ;ST(0)=sin2(x), ST(1)=sin(x), ST(2)=zzz
fld1 ;ST(0)=1.0, ST(1)=sin2(x), ST(2)=sin(x), ST(3)=zzz
fsubr ;ST(0)=1-sin2(x)=cos2(x), ST(1)=sin(x), ST(2)=zzz
fsqrt ;ST(0)=cos(x), ST(1)=sin(x), ST(2)=zzz
fpatan ;ST(0)=arcsin[sin(x)]=x (in radians), ST(1)=zzz



how to use it?

ArcCos (dy/dx) where dy < dx ? or (dy/hypot) because hypotenusa always big than dx or dy ?

For example:
x=100, x2=200
y=200,y2=700

dx=x2-x, dy=y2-y.
so dx=100, and dy=500. dy/dx= 5. ArcCos(5) are invalid right? (roticv said b/a. Not b/c ).
:confused: :stupid:
Posted on 2003-08-30 00:13:02 by realvampire
realvampire

Trigonometry is a branch of mathematics, the basics of which are usually covered during a full semester in high school.

I'm getting the impression that you have not yet reached that academic level or that you skipped those classes. It would be quite difficult to teach you a full semester course within a few paragraphs such that you would fully understand the entire subject.

AND this board is primarily designed for assembly programming subjects, not math courses. If you need to learn trigonometry, there are numerous sites on the Internet to get you started. One of them is the following:

http://www.sosmath.com/trig/trig.html

Raymond
Posted on 2003-08-30 07:12:07 by Raymond
Hey realvampire,

Why bother to use arccos when arctan could solve your problem?

cos x = adj/hypo
cos^-1 adj/hypo = x
sin x = opp/hypo
sin^-1 opp/hypo = x
tan x = opp/adj
tan^-1 opp/adj = x

cos^-1 = arccos, sin^-1 = arcsin, tan^-1 = arctan

b/a = gradient
gradient = tan x
Posted on 2003-08-30 09:39:06 by roticv