solve_theta_from_spiral_length: Get theta from given spiral lengths
In spiralize: Visualize Data on Spirals

Description Usage Arguments Details Value Examples

Get theta from given spiral lengths

1	solve_theta_from_spiral_length(len, interval = NULL, offset = 0)

`len`	A vector of spiral lengths.
`interval`	Interval to search for the solution.
`offset`	Offset of the spiral. In the general form: `r = a + r*theta`, offset is the value of `a`.

The length of the spiral has a complicated form, see https://downloads.imagej.net/fiji/snapshots/arc_length.pdf . Let's say the form is l = f(theta), solve_theta_from_spiral_length tries to find theta by a known l. It uses uniroot to search solutions.

The theta value.

spiral_initialize()
s = current_spiral()
theta = pi*seq(2, 3, length = 10)
len = s$spiral_length(theta)
solve_theta_from_spiral_length(len) # should be very similar as theta