Retired Computer Scientist: SRI-ARC (Engelbart),
Xerox PARC, Xerox SDS, Electronic Arts, SGI, Google, Box
Public
Edited
Apr 26, 2023
// Add your code here to do the wrangling steps above!
penguins
.map((d) => ({
species: d.species,
massKilograms: d.body_mass_g / 1000,
billRatio: d.culmen_length_mm / d.culmen_depth_mm
}))
.filter((d) => d.billRatio > 3.5)
penguinData
Type Table, then Shift-Enter. Ctrl-space for more options.
// Find the minimum culmen length in penguinData:
d3.min(penguinData, (d) => d.culmen_length_mm)
// Find the range of culmen lengths in penguinData:
d3.extent(penguinData, (d) => d.culmen_length_mm)
// Mean of all body mass (grams) values in penguinData:
d3.mean(penguinData, (d) => d.body_mass_g)
// Alternatively:
d3.mean(penguinData.map((d) => d.body_mass_g))
// Standard deviation of culmen depth:
d3.deviation(penguinData, (d) => d.body_mass_g)
// Count of flipper length values:
d3.count(penguinData, (d) => d.flipper_length_mm)
// Group penguinData by species (store Map as groupSpecies):
groupSpecies = d3.group(penguinData, (d) => d.species)
// Then get just the Adelies:
groupSpecies.get("Adelie")
// Group penguinData by species and island (store as groupSpeciesIsland):
groupSpeciesIsland = d3.group(
penguinData,
(d) => d.species,
(d) => d.island
)
// Get observations for Adelie penguins on Dream Island:
groupSpeciesIsland.get("Adelie").get("Dream")
// Find the mean body mass by penguin species:
d3.rollup(
penguinData,
(v) => d3.mean(v, (d) => d.body_mass_g),
(d) => d.species
)
// Find the mean flipper length by penguin species and sex:
d3.rollup(
penguinData,
(v) => d3.mean(v, (d) => d.flipper_length_mm),
(d) => d.species,
(d) => d.sex
)
arrayOfArrays = [
[1, 2],
[3, 4]
]
arrayOfArrays.map(([firstNumber, secondNumber]) => ({
firstNumber,
secondNumber
}))
// Use flatRollup to find mean body mass by penguin species, then map to get an array of objects:
d3
.flatRollup(
penguinData,
(v) => d3.mean(v, (d) => d.body_mass_g),
(d) => d.species
)
.map(([species, meanMass]) => ({ species, meanMass }))
// Create a new bar chart with Observable Plot to visualize mean body mass by species:
import { showMe } from "@observablehq/show-me"
Purpose-built for displays of data
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