A gaussian filter is fit to the surface measurements and residuals are calculated. The most extreme 0.25\ The result is called the raw signature of the bullet land.
Arguments
- ccdata
The crosscut as returned from x3p_to_df
- span
The size, in microns, of the smoothing window. Defaults to 600, which is 24\ 9mm land.
Value
a list of a data frame of the original bullet measurements extended by gaussian filtration, residuals, and two plots: a plot of the fit, and a plot of the bullet's land signature.
Examples
library(dplyr)
#>
#> Attaching package: ‘dplyr’
#> The following objects are masked from ‘package:stats’:
#>
#> filter, lag
#> The following objects are masked from ‘package:base’:
#>
#> intersect, setdiff, setequal, union
ccdata <- data_frame(
x = seq(0, 6000, 1),
value = 10 - (3 - x / 1000)^2 + rnorm(length(x), sd = .25)
)
#> Warning: `data_frame()` was deprecated in tibble 1.1.0.
#> ℹ Please use `tibble()` instead.
cc_fit_gaussian(ccdata = ccdata)
#> # A tibble: 6,001 × 7
#> x value fitted raw_sig se abs_resid chop
#> <dbl> <dbl> <dbl> <dbl> <lgl> <dbl> <lgl>
#> 1 0 0.650 1.55 -0.901 NA 0.901 TRUE
#> 2 1 1.07 1.55 -0.483 NA 0.483 FALSE
#> 3 2 0.403 1.56 -1.15 NA 1.15 TRUE
#> 4 3 1.02 1.56 -0.541 NA 0.541 FALSE
#> 5 4 1.18 1.56 -0.381 NA 0.381 FALSE
#> 6 5 1.32 1.56 -0.245 NA 0.245 FALSE
#> 7 6 0.581 1.56 -0.984 NA 0.984 TRUE
#> 8 7 0.980 1.57 -0.587 NA 0.587 FALSE
#> 9 8 0.987 1.57 -0.583 NA 0.583 FALSE
#> 10 9 0.983 1.57 -0.589 NA 0.589 FALSE
#> # ℹ 5,991 more rows