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## #1 2006-04-25 08:12:41

david_d
Guest

### calculating line angle

is there a way to calculate the angle of a line in a grid based system?

## #2 2006-04-25 08:31:44

Patrick
Real Member
Registered: 2006-02-24
Posts: 1,005

### Re: calculating line angle

I think trig is the tool you'll be needing here... This is, however, not a branch of mathematics I'm very familiar with.

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## #3 2006-04-25 10:08:26

david_d
Guest

### Re: calculating line angle

ok appraently u take the arc tangent of the slope to calculat the angle does any 1 know how to calculate the arc tangent?

## #4 2006-04-25 16:11:39

ganesh
Moderator
Registered: 2005-06-28
Posts: 21,812

### Re: calculating line angle

david_d,

If the equation of the straight line is
ax+by+c=0, then the slope is given by the formula

But the slope of the line is tan of the angle made with the x-axis.

Therefore,

The angle is the arctan of the slope m.

The arctan can be known by referring to tables or by using a calculator (scientific mode).

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david_d
Guest

thanks alot