First Command

First[ <List L> ]

Gives a new list that contains the first element of the list L.

Example:

First[{1, 4, 3}] yields {1}.

Note: To get the first element use Element[{1, 4, 3}, 1].

First[ <List L>, <Number n of elements> ]

Gives a new list that contains just the first n elements of the list L.

Example:

First[{1, 4, 3}, 2] yields {1, 4}.

First[ <Text> ]

Gives first character of the text.

Example:

First["Hello"] yields "H".

First[ <Text> , <Number n of elements> ]

Gives the first n characters of the text.

Example:

First["Hello",2] yields "He".

First[ <Locus>, <Number n of elements> ]

This command is useful for

• loci generated by SolveODE Command - It returns list points that were created in the first n steps of the numeric ODE-solving algorithm.
• loci generated using ShortestDistance Command, TravelingSalesman Command, Voronoi Command, MinimumSpanningTree Command, ConvexHull Command and Hull Command Commands - it returns vertices of the graph

CAS Syntax

First[ <List L> ]

Gives a new list that contains the first element of the list L.

Example:

First[{1, 4, 3}] yields {1}.

Note: To get the first element use Element[{1, 4, 3}, 1].

First[ <List L>, <Number n of elements> ]

Gives a new list that contains just the first n elements of the list L.

Example:

First[{1, 4, 3}, 2] yields {1, 4}.