Double normal curve

Calculate a double normal ogive (selectivity or maturity curve).

Usage

double_normal_ogive(x, x50, xl, xr)

Arguments

x

a numeric vector of length bin midpoints (mm).

x50

the size at 50% of the peak value (mm).

xl

the left-hand standard deviation parameter (mm).

xr

the right-hand standard deviation parameter (mm).

Value

a numeric vector of ogive values between 0 and 1.

Examples

double_normal_ogive(x = seq(31, 91, 2), x50 = 50, xl = 5, xr = 5)
#>  [1] 4.499113e-05 3.312022e-04 1.953125e-03 9.226505e-03 3.491522e-02
#>  [6] 1.058432e-01 2.570285e-01 5.000000e-01 7.791646e-01 9.726549e-01
#> [11] 9.726549e-01 7.791646e-01 5.000000e-01 2.570285e-01 1.058432e-01
#> [16] 3.491522e-02 9.226505e-03 1.953125e-03 3.312022e-04 4.499113e-05
#> [21] 4.895881e-06 4.267812e-07 2.980232e-08 1.667114e-09 7.470522e-11
#> [26] 2.681680e-12 7.711403e-14 1.776357e-15 3.277913e-17 4.845461e-19
#> [31] 5.737769e-21