TakeLargestBy
TakeLargestBy[data,f,n]
gives the n elements ei in data for which f[ei] is largest, sorted in descending order.
TakeLargestBy[dataprop,f,n]
gives the property prop for the n elements in data for which f[ei] is largest.
TakeLargestBy[data,f,n,p]
uses the ordering function p for sorting.
TakeLargestBy[f,n]
represents an operator form of TakeLargestBy that can be applied to an expression.
Details and Options
- TakeLargestBy gives the elements ei in the first level of the input data corresponding to the largest f[ei] values.
- By default, TakeLargestBy uses NumericalOrder to sort f[ei] values that are numeric expressions, Quantity objects and DateObject expressions. For other types of objects, TakeLargestBy sorts the f[ei] values by canonical Order.
- In TakeLargestBy[data,…], the data can have the following forms:
-
{e1,e2,…} list of values, including numbers, quantities, dates, ... Association[…] association of values » QuantityArray[…] quantity array or other structured array Tabular[…] type-consistent tabular data » TabularColumn[…] type-consistent column data » Dataset[…] general hierarchical data » - TakeLargestBy[assoc,f,n] gives an association of length n by taking the values in assoc that are largest according to f, preserving their keys.
- For tabular data tab, TakeLargestBy[tab,f,…] applies the function f to individual rows of tab, with the row being an association <col1val1,… > if tab has column keys or a list {val1,…} if tab does not have column keys.
- In TakeLargestBy[dataprop,f,n], possible forms for prop include:
-
"Element" gives each element itself » "Index" gives the index for each element » "Value" gives the value f[x] for each element x » {prop1,prop2,…} a list of multiple forms » All gives an association with element, index and f value » - TakeLargestBy[data,f,UpTo[n]] takes n elements, or as many as are available. »
- TakeLargestBy[f,n][data] is equivalent to TakeLargestBy[data,f,n].
- TakeLargestBy has option ExcludedForms. With the default setting ExcludedForms->Automatic, TakeLargestBy excludes from its final results elements for which f[ei] is None, Null or Indeterminate or has head Missing. »
- The setting ExcludedForms->{patt1,patt2,…} specifies that expressions for which f[ei] matches any of the patti should be excluded from results generated by TakeLargestBy. »
Examples
open allclose allBasic Examples (5)
Give the four numbers farthest from zero:
Take the two longest strings in a list:
Do the same using the operator form of TakeLargestBy:
Take the three largest Quantity lengths according to their distance to :
Take the three DateObject expressions with the largest day of the month:
Scope (8)
Give the four numbers farthest from zero, or as many as are available if fewer:
The discovery date value for some planets is missing:
By default, Missing[] and several other symbolic expressions are excluded if returned by the selection function:
Get the two largest elements by magnitude in a list:
Get the positions of the two largest elements by magnitude in a list:
Get the two largest magnitudes in a list:
Get the two largest elements by magnitude in a list along with their positions:
Get the two largest elements by magnitude in a list with their positions given first:
Get associations containing the element, position and Abs value of the two largest elements by magnitude in a list:
They can be translated to Spanish with WordTranslation, which gives a list of possibilities:
These are the largest two words according to canonical order:
These are the largest two English words according to canonical order of their Spanish translations:
Use properties to show simultaneously the English word and its translation to Spanish:
Construct a TabularColumn object with 100 words:
Select the five longest words:
Normalize the result to a list:
Find the four rows in a Tabular object with largest values in a given column:
Use general functional notation instead of the column name:
Take a dataset of the solar system planets:
Find the three planets with the largest number of moons:
Take a list of integer 3-vectors:
Select the three vectors with largest norms, by default sorting numerically those norms:
Sorting the norms by canonical order can give a different result:
Options (2)
ExcludedForms (2)
Take the list of all planets in the solar system:
Find the four planets that are currently farthest from your location, with a limit of 15 au in distance:
Plot the evolution of the distances during a two-year period centered at the current moment:
Not all these keys have values in the association:
Find the keys corresponding to the two largest values in the association:
By default, some symbolic objects like Missing[] or None are excluded as results of the selection function, so the previous result is equivalent to this:
Specify that no value should be excluded:
Specify that only values with Missing head should be excluded:
Applications (6)
Find the eight capitals of continental US states that are farthest from Kansas City:
Find the five most recent James Bond movies:
Find the 10 countries with the longest names:
From the BRICS group of countries, give the country that is farthest from your location:
Find the four US states with the largest number of neighboring states, and show them:
Find the five constellations with largest number of bright stars, showing how many each one has:
Properties & Relations (3)
TakeLargestBy[list,f,n,p] is effectively equivalent to Part[list,TakeLargest[Map[f,list]"Index",n,p]]:
TakeLargestBy[{e1,e2,…},f,n] compares values f[ei] using NumericalOrder by default:
MaximalBy[{e1,e2,…},f,n] compares values f[ei] using canonical Order by default:
Both TakeLargestBy and MaximalBy take an ordering function as fourth argument, which makes them effectively equivalent:
When there are common values of f[ei] for different elements ei in TakeLargestBy[{e1,e2,…},f,n], the original order will be kept:
Possible Issues (2)
If fewer than the requested number of elements are present, TakeLargestBy will not evaluate:
Use UpTo to get as many elements as possible:
If the f[ei] are not comparable, TakeLargestBy will not evaluate:
Text
Wolfram Research (2015), TakeLargestBy, Wolfram Language function, https://reference.wolfram.com/language/ref/TakeLargestBy.html (updated 2025).
CMS
Wolfram Language. 2015. "TakeLargestBy." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2025. https://reference.wolfram.com/language/ref/TakeLargestBy.html.
APA
Wolfram Language. (2015). TakeLargestBy. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/TakeLargestBy.html