Home - News ( United States | United Kingdom | Italy | Germany ) - Football scores

Showing content from http://reference.wolfram.com/language/ref/SelectFirst.html below:

SelectFirst—Wolfram Language Documentation

We deliver solutions for the AI era—combining symbolic computation, data-driven insights and deep technology expertise.

• Data & Computational Intelligence
• Model-Based Design
• Algorithm Development
• Wolfram|Alpha for Business
• Blockchain Technology
• Education Technology
• Quantum Computation

WolframConsulting.com

• See Also
  • Select
  • FirstCase
  • FirstPosition
  • First
  • Take
  • Drop
  • Reap
  • Pick
  • GatherBy
  • GroupBy
  • MatchQ
  • StringMatchQ
  • FreeQ
• Related Guides
  • Elements of Lists
  • Computation with Structured Datasets
  • Function Composition & Operator Forms

SelectFirst[data,crit]

gives the first e_i of data for which crit[e_i] is True, or Missing["NotFound"] if none is found.

SelectFirst[data,critprop]

returns the property prop of the selected elements.

SelectFirst[data,crit,default]

gives default if there is no e_i of data such that crit[e_i] is True.

• SelectFirst keeps the first element for which the given criterion crit is True:
• SelectFirst[data,crit] is equivalent to First[Select[data,crit]].
• The data can have the following additional forms and interpretations:
• The property prop can have the following forms and interpretations:
• "Element" the selected values » "Index" indices of the selected values » "BitVectorMask" Boolean mask returning True for slected values and False otherwise » {prop₁,prop₂,…} a list of multiple forms » All an association giving element, index and bit vector mask »
• In SelectFirst[data,crit,default], default is only evaluated if there is no e_i in data such that crit[e_i] is True.
• SelectFirst[crit][data] is equivalent to SelectFirst[data,crit].

Select the first element that is even:

Return the index of the selected element:

Give the default x when no even numbers are found:

Use the operator form of SelectFirst:

SelectFirst operates on values in an Association:

Use SelectFirst with a Tabular object:

Find the first pair containing x:

Use a pure function to test elements:

Use an operator form as selection criterion:

Use SelectFirst in operator form:

Use a custom default value:

Return the selected element:

Return the index of the selected element:

Return the Boolean mask of the data:

Return two forms:

Return the association with all the properties:

Select the first number between 9 and 99 that equals 1 modulo both 3 and 5:

Select the first 4-tuple that reads the same in reverse:

Find the first 3×3 matrix of 0s and 1s that has determinant 1:

Select an eigenvalue that lies within the unit circle:

Find the first built-in Wolfram Language object whose name is at least 36 characters long:

Select the first numeric quantity from a product:

Find the position of the first prime in a random sample from a PoissonDistribution:

Find the distribution of positions of first primes:

The default value is only evaluated if needed:

SelectFirst returns only the first match:

Select returns all matches:

SelectFirst can be implemented with a combination of Select and Replace:

SelectFirst is similar to FirstCase except that it uses a function instead of a pattern:

Select the first list that has a sum of elements less than 10:

Use FirstCase to get the same result:

The head of the input expression is not preserved:

RetroSearch is an open source project built by @garambo | Open a GitHub Issue

Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo

HTML: 3.2 | Encoding: UTF-8 | Version: 0.7.4