randomness concept

concepts/randomness/.meta/config.json

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+{
+  "authors": ["colinleach"],
+  "contributors": [],
+  "blurb": "R offers a rich variety of ways to generate random values, for many statistical distributions."
+}

concepts/randomness/about.md

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+# About
+
+R was derived from a statistics package and is often used for simulations, so it offers a rich variety of ways to generate random values.
+These are a few common ones.
+
+## Discrete values with `sample`
+
+To pick from a limited number of discrete values, `sample()` can be used with or without replacement (i.e. is it permitted to get repeated values?).
+This is useful for integers, strings, etc.
+
+```R
+> sample(1:10, 5) # no repeats
+[1] 8 3 4 2 6
+
+> sample(1:10, 5, replace = TRUE) # repeats are OK
+[1] 10 10  7 10  9
+
+> languages <- c("Fortran", "R", "Python", "Julia")
+> sample(languages, 1)
+[1] "Python"
+
+> sample(c(TRUE, FALSE), 5, replace = TRUE) # coin flips
+[1] FALSE  TRUE FALSE  TRUE  TRUE
+```
+
+## Floating-point numbers
+
+For a random-uniform distribution use `runif()`.
+Both `min` and `max` can be specified but default to 0 and 1.
+
+```R
+> runif(5)
+[1] 0.3038506 0.3527959 0.3319309 0.4846354 0.4386279
+
+> runif(5, max = 100)
+[1] 79.70762 51.62232 52.85281 71.08571 63.94380
+```
+
+Other common distributions include `rnorm()` for Gaussian, `rbinom()` for binomial, `rpois()` for Poisson, etc.

concepts/randomness/introduction.md

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+# Introduction
+
+There are many options for generating random values, and these are a few common ones.
+
+## Discrete values with `sample`
+
+To pick from a limited number of discrete values, `sample()` can be used with or without replacement (i.e. is it permitted to get repeated values?).
+This is useful for integers, strings, etc.
+
+```R
+> sample(1:10, 5) # no repeats
+[1] 8 3 4 2 6
+
+> sample(1:10, 5, replace = TRUE) # repeats are OK
+[1] 10 10  7 10  9
+
+> languages <- c("Fortran", "R", "Python", "Julia")
+> sample(languages, 1)
+[1] "Python"
+
+> sample(c(TRUE, FALSE), 5, replace = TRUE) # coin flips
+[1] FALSE  TRUE FALSE  TRUE  TRUE
+```
+
+## Floating-point numbers
+
+For a random-uniform distribution use `runif()`.
+Both `min` and `max` can be specified but default to 0 and 1.
+
+```R
+> runif(5)
+[1] 0.3038506 0.3527959 0.3319309 0.4846354 0.4386279
+
+> runif(5, max = 100)
+[1] 79.70762 51.62232 52.85281 71.08571 63.94380
+```

concepts/randomness/links.json

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+[
+  {
+    "url": "http://www.cookbook-r.com/Numbers/Generating_random_numbers/",
+    "description": "Cookbook for R"
+  },
+  {
+    "url": "https://www.educba.com/random-number-generator-in-r/",
+    "description": "EDUCBA"
+  },
+  {
+    "url": "https://www.statology.org/r-random-number/",
+    "description": "Statology"
+  }
+]

config.json

@@ -569,6 +569,11 @@
       "uuid": "2751b6f2-7d71-4397-b063-9bf927a57756",
       "slug": "booleans",
       "name": "Booleans"
+    },
+    {
+      "uuid": "9de56486-6c39-4c08-9d5a-db78a524b0b1",
+      "slug": "randomness",
+      "name": "Randomness"
     }
   ],
   "key_features": [