It looks like you're new here. If you want to get involved, click one of these buttons!

- 140.9K All Categories
- 103.7K Programming Languages
- 6.5K Assembler Developer
- 1.9K Basic
- 40K C and C++
- 2.9K C#
- 7.9K Delphi and Kylix
- 4 Haskell
- 9.7K Java
- 4.1K Pascal
- 1.3K Perl
- 2K PHP
- 550 Python
- 37 Ruby
- 4.4K VB.NET
- 1.6K VBA
- 20.9K Visual Basic
- 2.6K Game programming
- 317 Console programming
- 92 DirectX Game dev
- 1 Minecraft
- 112 Newbie Game Programmers
- 2 Oculus Rift
- 9K Applications
- 1.8K Computer Graphics
- 742 Computer Hardware
- 3.4K Database & SQL
- 535 Electronics development
- 1.6K Matlab
- 628 Sound & Music
- 258 XML Development
- 3.3K Classifieds
- 199 Co-operative Projects
- 198 For sale
- 190 FreeLance Software City
- 1.9K Jobs Available
- 603 Jobs Wanted
- 209 Wanted
- 2.9K Microsoft .NET
- 1.8K ASP.NET
- 1.1K .NET General
- 3.4K Miscellaneous
- 8 Join the Team
- 355 Comments on this site
- 70 Computer Emulators
- 2.1K General programming
- 187 New programming languages
- 627 Off topic board
- 207 Mobile & Wireless
- 79 Android
- 126 Palm Pilot
- 338 Multimedia
- 154 Demo programming
- 184 MP3 programming
- Bash scripts
- 27 Cloud Computing
- 53 FreeBSD
- 1.7K LINUX programming
- 370 MS-DOS
- Shell scripting
- 321 Windows CE & Pocket PC
- 4.1K Windows programming
- 942 Software Development
- 417 Algorithms
- 68 Object Orientation
- 92 Project Management
- 95 Quality & Testing
- 269 Security
- 7.7K WEB-Development
- 1.8K Active Server Pages
- 62 AJAX
- 4 Bootstrap Themes
- 55 CGI Development
- 28 ColdFusion
- 224 Flash development
- 1.4K HTML & WEB-Design
- 1.4K Internet Development
- 2.2K JavaScript
- 37 JQuery
- 307 WEB Servers
- 150 WEB-Services / SOAP

James S
Member Posts: **14**

in Algorithms

If I have x & y coordinates to 2 points,

point 1 would serve to be the center of an imaginary circle.

point 2 could be any point in relation to point 1.

I want to know the degree of an angle that would be created with the 2 points (assuming the 1st line of the angle is straight up from point 1, the 2nd line is the line connecting point 1 with point 2)

Example.

Point 1 = 50,100

Point 2 = 52,100 or 354,100

Degree would be 90 (a perfect right angle)

I'm sure there's a mathematical formula for this but I don't know it... can anyone help?

point 1 would serve to be the center of an imaginary circle.

point 2 could be any point in relation to point 1.

I want to know the degree of an angle that would be created with the 2 points (assuming the 1st line of the angle is straight up from point 1, the 2nd line is the line connecting point 1 with point 2)

Example.

Point 1 = 50,100

Point 2 = 52,100 or 354,100

Degree would be 90 (a perfect right angle)

I'm sure there's a mathematical formula for this but I don't know it... can anyone help?

Terms of use / Privacy statement / Publisher: Lars Hagelin

Programmers Heaven articles / Programmers Heaven files / Programmers Heaven uploaded content / Programmers Heaven C Sharp ebook / Operated by CommunityHeaven

© 1997-2015 Programmersheaven.com - All rights reserved.

## Comments

272most languages have them

13360*(1 - cos'(h/w)/pi)

where

cos'() is inverse cos()

h = |y2-y1|

w = |x2-x1|

pi = 3.1415

if you're after speed or your software does not support trig functions you can easily formulate a polynomial to approximate for quandrant 1 using series and mirror|translate for all other angles.

21: 360*(1 - cos'(h/w)/pi)

: where

: cos'() is inverse cos()

: h = |y2-y1|

: w = |x2-x1|

: pi = 3.1415

:

: if you're after speed or your software does not support trig functions you can easily formulate a polynomial to approximate for quandrant 1 using series and mirror|translate for all other angles.

:

If you aren't satified with this or you can't use the trig functions for some reason I will supply you with them (the real onece)in a few days when I get home (I'm at my sisters place.. no notes filling my desk). They are not easy to understand mind you and they certainly are not easy to use either.

1David

21: David

:

:

let me see if I got this right:

you got degree a and degree b and you need to find (a+b)/2?

it's quite simple if that's what you need. If not I'm not understanding this correctly

3: David

:

:

Good question Dave, easy answer

((argument1 + argument2) % 360) / 2

the % is for modulus.

3: : David

: :

: :

: Good question Dave, easy answer

:

: ((argument1 + argument2) % 360) / 2

:

: the % is for modulus.

:

sorry, that is not right answer, let me check some notes when i get home tonight, i solved this before.

3: : : David

: : :

: : :

: : Good question Dave, easy answer

: :

: : ((argument1 + argument2) % 360) / 2

: :

: : the % is for modulus.

: :

:

: sorry, that is not right answer, let me check some notes when i get home tonight, i solved this before.

:

~~~~~~~~~~~~~~

One way to solve problem is break into two parts.

Trouble comes when the numerical difference between arguments is greater than 180. Also, an exact difference of 180 can go either direction.

INPUT ARG1, ARG2

IF ABS(ARG1 - ARG2) <= 180

ANSWER = (ARG1 + ARG2) / 2

ELSE

ANSWER = ???

ENDIF

The else clause is harder to work out. But the IFTHENELSE construct will at least identify the 'situation' where special processing is needed.

Hope that helps.

I haven't taken any trigonometry, but i'll bet there is a formula which can work in all situtations.