Difference between revisions of "First Command"
From GeoGebra Manual
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{{command|list}} | {{command|list}} | ||
;First[ <List L> ] | ;First[ <List L> ] | ||
− | :Gives | + | :Gives the first element of the list ''L''. |
− | :{{example|1=<div><code><nowiki>First[{1, 4, 3}]</nowiki></code> | + | :{{example|1=<div><code><nowiki>First[{1, 4, 3}]</nowiki></code> yields ''1''.</div>}} |
− | :{{note| 1=To get the first element | + | :{{note| 1=To get the list containing only the first element use <code><nowiki>First[{1, 4, 3}, 1]</nowiki></code>.}} |
;First[ <List L>, <Number n of elements> ] | ;First[ <List L>, <Number n of elements> ] | ||
:Gives a new list that contains just the first ''n'' elements of the list ''L''. | :Gives a new list that contains just the first ''n'' elements of the list ''L''. | ||
Line 19: | Line 19: | ||
==CAS Syntax== | ==CAS Syntax== | ||
;First[ <List L> ] | ;First[ <List L> ] | ||
− | :Gives | + | :Gives the first element of the list ''L''. |
− | :{{example|1=<div><code><nowiki>First[{1, 4, 3}]</nowiki></code> | + | :{{example|1=<div><code><nowiki>First[{1, 4, 3}]</nowiki></code> yields ''1''.</div>}} |
− | :{{note| 1=To get the first element | + | :{{note| 1=To get the list containing only the first element use <code><nowiki>First[{1, 4, 3}, 1]</nowiki></code>.}} |
;First[ <List L>, <Number n of elements> ] | ;First[ <List L>, <Number n of elements> ] | ||
:Gives a new list that contains just the first ''n'' elements of the list ''L''. | :Gives a new list that contains just the first ''n'' elements of the list ''L''. | ||
:{{example|1=<div><code><nowiki>First[{1, 4, 3}, 2]</nowiki></code> returns ''{1, 4}''.</div>}} | :{{example|1=<div><code><nowiki>First[{1, 4, 3}, 2]</nowiki></code> returns ''{1, 4}''.</div>}} |
Revision as of 15:14, 5 August 2011
- First[ <List L> ]
- Gives the first element of the list L.
- Example:
First[{1, 4, 3}]
yields 1.
- Note: To get the list containing only the first element use
First[{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]
returns {1, 4}.
- First[ <Text> ]
- Gives first character of the text.
- First[ <Text> , <Number n of elements> ]
- Gives the first n characters of the text.
- Example:
First["Hello",2]
returns "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 the first element of the list L.
- Example:
First[{1, 4, 3}]
yields 1.
- Note: To get the list containing only the first element use
First[{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]
returns {1, 4}.