Difference between revisions of "First Command"
From GeoGebra Manual
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<noinclude>{{Manual Page|version=4.0}}[[Category:Manual (official)|{{PAGENAME}}]]</noinclude> | <noinclude>{{Manual Page|version=4.0}}[[Category:Manual (official)|{{PAGENAME}}]]</noinclude> | ||
{{command|list}} | {{command|list}} | ||
| − | ;First[List L]: Returns a list containing the first element of the list ''L''. | + | ;First[ <List L> ] |
| + | :Returns a list containing the first element of the list ''L''. | ||
{{example|1=<div><code><nowiki>First[{1,2,3}]</nowiki></code> returns ''{1}''.</div>}} | {{example|1=<div><code><nowiki>First[{1,2,3}]</nowiki></code> returns ''{1}''.</div>}} | ||
To get the first element itself use e.g. [[Element Command]]. | To get the first element itself use e.g. [[Element Command]]. | ||
| − | ;First[List L, Number n of elements]: Returns a new list that contains just the first ''n'' elements of the list ''L''. | + | ;First[ <List L>, <Number n of elements> ] |
| − | ;First[Text]:Returns first character of the text. | + | :Returns a new list that contains just the first ''n'' elements of the list ''L''. |
| − | ;First[Text, Number n of elements]: Returns the first ''n'' characters of the text. | + | ;First[ <Text> ] |
| + | :Returns first character of the text. | ||
| + | ;First[ <Text> , <Number n of elements> ] | ||
| + | :Returns the first ''n'' characters of the text. | ||
{{example|1=<div><code><nowiki>First["Hello",2]</nowiki></code> returns "He".</div>}} | {{example|1=<div><code><nowiki>First["Hello",2]</nowiki></code> returns "He".</div>}} | ||
| − | ;First[Locus, Number n of elements]: This command is useful for | + | ;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 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 | :*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== | ==CAS Syntax== | ||
| − | ;First[List L]: Returns a list containing the first element of the list ''L''. | + | ;First[ <List L> ] |
| + | :Returns a list containing the first element of the list ''L''. | ||
{{example|1=<div><code><nowiki>First[{1,2,3}]</nowiki></code> returns ''{1}''.</div>}} | {{example|1=<div><code><nowiki>First[{1,2,3}]</nowiki></code> returns ''{1}''.</div>}} | ||
To get the first element itself use e.g. [[Element Command]]. | To get the first element itself use e.g. [[Element Command]]. | ||
| − | ;First[List L, Number n of elements]: Returns a new list that contains just the first ''n'' elements of the list ''L''. | + | ;First[ <List L>, <Number n of elements> ] |
| − | + | :Returns a new list that contains just the first ''n'' elements of the list ''L''. | |
| − | |||
| − | |||
Revision as of 11:51, 5 August 2011
- First[ <List L> ]
- Returns a list containing the first element of the list L.
Example:
First[{1,2,3}] returns {1}.To get the first element itself use e.g. Element Command.
- First[ <List L>, <Number n of elements> ]
- Returns a new list that contains just the first n elements of the list L.
- First[ <Text> ]
- Returns first character of the text.
- First[ <Text> , <Number n of elements> ]
- Returns 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> ]
- Returns a list containing the first element of the list L.
Example:
First[{1,2,3}] returns {1}.To get the first element itself use e.g. Element Command.
- First[ <List L>, <Number n of elements> ]
- Returns a new list that contains just the first n elements of the list L.
