The goal of rando is to provide easier generating of random numbers in a manner that is context aware, and reproducible.
You can install the released version of rando from CRAN with:
You can install the development version of rando from Github with:
Once installed, to load rando
, use
With rando, generating random numbers becomes incredibly easy, as we do not need to define how many random numbers we need. rando
will figure out how many you need based on where the number generator is being used.
This works for tibble()
declarations
df <- tibble(id = 1:10,
x = r_norm())
df
#> # A tibble: 10 x 2
#> id x
#> <int> <dbl>
#> 1 1 -0.365
#> 2 2 0.173
#> 3 3 -0.294
#> 4 4 0.576
#> 5 5 0.875
#> 6 6 0.359
#> 7 7 -0.527
#> 8 8 -0.819
#> 9 9 -0.990
#> 10 10 0.518
and inside of dplyr
verbs
mutate(df, y = r_unif())
#> # A tibble: 10 x 3
#> id x y
#> <int> <dbl> <dbl>
#> 1 1 -0.365 0.210
#> 2 2 0.173 0.354
#> 3 3 -0.294 0.317
#> 4 4 0.576 0.0695
#> 5 5 0.875 0.125
#> 6 6 0.359 0.169
#> 7 7 -0.527 0.305
#> 8 8 -0.819 0.601
#> 9 9 -0.990 0.483
#> 10 10 0.518 0.300
Parameters can also be used to define the number of values to return. If parameters are longer than 1, rando
will try to return the same number of random values, unless there is a clash between two of the parameters
r_norm(mean = 1:10)
#> [1] 0.4088105 2.2987041 2.2807546 3.9659070 4.5111552 5.4712253 6.5461452
#> [8] 6.3708207 7.7550056 8.7627581
r_norm(mean=1:10,sd=1:2)
#> Error: Inconsistent parameter lengths supplied to r_norm()
If you want to manually define the number of random numbers to be generated, there are two ways to do it. The old fashioned way: providing the n
argument (this must be named)
r_unif(n=20)
#> [1] 0.75427791 0.97153547 0.06031924 0.43098427 0.45223070 0.54105261
#> [7] 0.13882213 0.86252549 0.31421104 0.97247948 0.29288323 0.03809931
#> [13] 0.55187415 0.51237188 0.45841500 0.12699633 0.15236584 0.08755528
#> [19] 0.78088410 0.83223010
Or, if we are generating many random numbers, we can set a default n
value to be used globally
The rando
functions also check if parameters being supplied are viable and throws an informative error if not. This is different to the default stats
random number generating functions, which may return a lot of NaN
values with only a vague warning.
rnorm(n=10,sd=-1)
#> Warning in rnorm(n = 10, sd = -1): NAs produced
#> [1] NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN
r_norm(sd=-1)
#> Error: sd provided to r_norm() must be strictly positive
All rando
functions can also take a .seed
argument which does one of two things:
rando
will set this as the random seed before generating the valuesrando
will randomly generate a numeric value to be used.If .seed
is not NULL
(the default), then this seed
value (supplied or generated) will be attached to the output, and can be extracted with pull_seed()
This allows for greater replicability in results.
r_norm(.seed = 42)
#> [1] 1.37095845 -0.56469817 0.36312841 0.63286260 0.40426832 -0.10612452
#> [7] 1.51152200 -0.09465904 2.01842371 -0.06271410 1.30486965 2.28664539
#> [13] -1.38886070 -0.27878877 -0.13332134
#> attr(,"seed")
#> [1] 42
r_norm(.seed = 42)
#> [1] 1.37095845 -0.56469817 0.36312841 0.63286260 0.40426832 -0.10612452
#> [7] 1.51152200 -0.09465904 2.01842371 -0.06271410 1.30486965 2.28664539
#> [13] -1.38886070 -0.27878877 -0.13332134
#> attr(,"seed")
#> [1] 42
x <- r_norm(.seed=TRUE)
x
#> [1] -1.0515017 2.8143380 1.1880200 -1.2010801 -1.1589546 -0.1876997
#> [7] -0.1515049 0.7168907 -0.2086623 -1.0248107 0.7394365 -0.5944315
#> [13] -1.9588881 0.5869532 0.6124257
#> attr(,"seed")
#> [1] 1020465408
r_norm(.seed=pull_seed(x))
#> [1] -1.0515017 2.8143380 1.1880200 -1.2010801 -1.1589546 -0.1876997
#> [7] -0.1515049 0.7168907 -0.2086623 -1.0248107 0.7394365 -0.5944315
#> [13] -1.9588881 0.5869532 0.6124257
#> attr(,"seed")
#> [1] 1020465408
In order to make simulations easier, rando
provides the blueprint()
function. This function creates a plan for a simulated dataset using rando
functions.
make_tbl <- blueprint(
x = r_norm(),
y = r_norm()
)
make_tbl(n=2)
#> # A tibble: 2 x 2
#> x y
#> <dbl> <dbl>
#> 1 -1.89 1.34
#> 2 -2.28 0.913
make_tbl(n=5)
#> # A tibble: 5 x 2
#> x y
#> <dbl> <dbl>
#> 1 0.316 -0.154
#> 2 1.86 1.46
#> 3 -0.396 -1.42
#> 4 -1.08 0.481
#> 5 1.75 0.323
These blueprints can accept additional arguments and will be generated based on these arguments
make_tbl2 <- blueprint(
x = r_norm(mean=x_mu),
y = r_unif(min=y_min,max=y_max)
)
set_n(10000)
make_tbl2(x_mu = 10, y_min = -10, y_max=-5) %>%
summarise(n = n(), mean_x = mean(x), min_y = min(y), max_y = max(y))
#> # A tibble: 1 x 4
#> n mean_x min_y max_y
#> <int> <dbl> <dbl> <dbl>
#> 1 10000 10.0 -10.0 -5.00
This then allows for quick generation of simulation data using pmap()
and analysis using map()
make_sim <- blueprint(
x = r_norm(mean = x_mu),
y = r_norm(mean = 2*x+10, sd = 2)
)
tibble(x_mu = r_unif(n = 5, -10, 10)) %>%
pmap(make_sim, n = 100) %>%
map(lm, formula = y ~ x) %>%
map_dfr(broom::tidy)
#> # A tibble: 10 x 5
#> term estimate std.error statistic p.value
#> <chr> <dbl> <dbl> <dbl> <dbl>
#> 1 (Intercept) 9.29 1.35 6.89 5.45e-10
#> 2 x 1.92 0.202 9.48 1.60e-15
#> 3 (Intercept) 8.69 0.723 12.0 5.58e-21
#> 4 x 2.38 0.193 12.3 1.32e-21
#> 5 (Intercept) 10.6 0.726 14.6 2.91e-26
#> 6 x 1.82 0.252 7.20 1.22e-10
#> 7 (Intercept) 10.1 0.770 13.1 3.20e-23
#> 8 x 2.06 0.202 10.2 4.72e-17
#> 9 (Intercept) 9.78 0.426 22.9 3.54e-41
#> 10 x 1.68 0.218 7.72 1.02e-11
The majority of random number generating functions from the stats
package have been translated into rando
functions. Be sure to look into the documentation for the rando
functions you use, as some have re-parametrised. Functions names for transitioning from stats
to rando
generally follow the same naming convention, that is r*()
becomes r_*()
, e.g. r_norm()
replaces rnorm()
. The only exceptions are r_tdist()
and r_fdist()
to take over the roles of rt()
and rf()
, respectively. rando
also includes several new distributions such as r_bern()
and r_letters()
.
The r_cdf()
function is a dynamic random number generator. It can take any cdf as an argument and produce random numbers with the associated distribution.
my_fun <- function(x,beta=1){
if_else(x < 0, 0, 1-exp(-beta*x))
}
set_n(1000)
x_data <- r_cdf(my_fun)
hist(x_data,breaks=seq(0,10,0.1))
Any additional arguments used by the function, can be passed to r_cdf()
, and will be used in determining the number of values to generate (just as in the other distribution functions above)
r_cdf(my_fun,beta=1:10)
#> [1] 1.59363151 0.01710057 0.51777959 0.10563731 0.15656352 0.04890561
#> [7] 0.05313754 0.10311007 0.01916289 0.09977221
Finally, purrr
-style functions can be used for r_cdf()
to allow for even briefer function definitions. These have been extended to allow for the use of additional named arguments to be passed to these <lambda>
functions. Either .x
or .t
can be used for the random variable.
set_n(20)
r_cdf(~1-exp(-.x),min=0)
#> [1] 1.00280643 0.51202178 3.15050483 0.38757920 0.16273856 1.37652755
#> [7] 0.41813254 1.14622712 1.26543641 0.01011491 0.65036416 1.35177970
#> [13] 1.25859380 0.30105710 1.45331025 0.22260547 1.71133876 0.12983680
#> [19] 0.41169524 0.26691556
r_cdf(~1-exp(-beta*.x),beta=1:10,min=0,n=10)
#> [1] 0.892275572 0.172501802 0.160342455 0.432735682 0.299936533 0.004011393
#> [7] 0.133234262 0.150531530 0.004047155 0.426167250
Please note that the rando project is released with a Contributor Code of Conduct. By contributing to this project, you agree to abide by its terms.