Displaying 4 results from an estimated 4 matches for "nistradiantodeg".
2018 Jan 30
2
Calculating angle of a polyline
...)) && (length(xV) >= 3))
v <- function(i) { c( xV[i]-xV[i-1], yV[i]-yV[i-1])}
vlen <- function(v) { sqrt(sum(v*v)) }
lV <- rep(NA_real_,length(xV))
for ( i in 2:(length(xV)-1) )
lV[i] <- acos( sum(v(i)*v(i+1))/(vlen(v(i))*vlen(v(i+1))) )
angleV <- NISTunits::NISTradianTOdeg(lV)
angleV
}
# example
x <- c(0:3)
y <- c(0,0,1,1)
polyangles( x, y )
# NA 45.0 45.0 NA
Note, I have included the NA's at the beginning and end of the polyline as
a reminder that there is no angle defined there.
HTH,
Eric
On Tue, Jan 30, 2018 at 4:34 PM, Jeff Newmiller <jdnewmi...
2018 Jan 30
0
Calculating angle of a polyline
...)
> v <- function(i) { c( xV[i]-xV[i-1], yV[i]-yV[i-1])}
> vlen <- function(v) { sqrt(sum(v*v)) }
>
> lV <- rep(NA_real_,length(xV))
> for ( i in 2:(length(xV)-1) )
> lV[i] <- acos( sum(v(i)*v(i+1))/(vlen(v(i))*vlen(v(i+1))) )
> angleV <- NISTunits::NISTradianTOdeg(lV)
> angleV
> }
>
> # example
> x <- c(0:3)
> y <- c(0,0,1,1)
> polyangles( x, y )
>
> # NA 45.0 45.0 NA
>
> Note, I have included the NA's at the beginning and end of the polyline as
> a reminder that there is no angle defined there.
>
> HTH,...
2018 Jan 30
2
Calculating angle of a polyline
Dear R users
I am trying to find a formula to calculate the angle of a polyline. Is
there a way to do this?
Many thanks.
--
Best Regards
Javad Bayat
M.Sc. Environment Engineering
Alternative Mail: bayat194 at yahoo.com
[[alternative HTML version deleted]]
2018 Jan 30
0
Calculating angle of a polyline
A polyline by definition has many angles, so your question is ill-formed. And this is a question about math, not R, so is off topic here. I suggest reading Wikipedia.
--
Sent from my phone. Please excuse my brevity.
On January 29, 2018 11:10:02 PM PST, javad bayat <j.bayat194 at gmail.com> wrote:
>Dear R users
>I am trying to find a formula to calculate the angle of a polyline. Is