Public
Edited
Jun 9, 2023
// Add your code here to do the wrangling steps above!
penguinData.map(d => ({
species: d.species,
massKg: d.body_mass_g / 1000,
billRatio: (d.culmen_length_mm / d.culmen_depth_mm).toFixed(2)
}))
.filter(d => d.billRatio > 3.5)
// Find the minimum culmen length in penguinData:
d3.min(penguinData, d => d.culmen_length_mm)
// Find the range of culmen lengths in penguinData: d3.min(penguinData, d => d.culmen_length_mm)
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)
d3.mean(penguinData.map(d => d.body_mass_g))
// Alternatively:
// Standard deviation of culmen depth:
d3.deviation(penguinData, d => d.culmen_depth_mm)
// Count of flipper length values:
d3.count(penguinData, d => d.flipper_length_mm)
penguinData
Type Table, then Shift-Enter. Ctrl-space for more options.
penguinData
Type Table, then Shift-Enter. Ctrl-space for more options.
groupSpecies = d3.group(penguinData, d => d.species)
groupSpecies.get("Adelie")
// Group penguinData by species (store Map as groupSpecies):
map1 = new Map()
map1.set(d => 2 * d, "hello")
// Then get just the Adelies:
// Group penguinData by species and island (store as groupSpeciesIslgroupand):
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:
// 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(([firstNum, secondNum]) => ({
firstNum,
secondNum
}))
// Use flatRollup to find mean body mass by penguin species, then map to get an array of objects:
d3.rollup(penguinData,
v => d3.mean(v, d => d.body_mass_g), // reducer function - gets a group of data (v) passed to it
d => d.species) // grouping function
d3.flatRollup(penguinData,
// summarising function
v => d3.mean(v, d => d.body_mass_g),
// grouping functions
d => d.species,
d => d.sex)
.map(([species, sex, meanMass]) => ({ species, sex, 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
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
