home *** CD-ROM | disk | FTP | other *** search
/ Celestin Apprentice 4 / Apprentice-Release4.iso / Languages / RLaB 1.18c / manual / exist.tex < prev    next >
LaTeX Document  |  1994-05-01  |  1.2 KB  |  [TEXT/ttxt]

open in: MacOS 8.1     |     Win98     |     DOS

view JSON data     |     view as text

This file was processed as: LaTeX Document (document/latex).

You can browse this item here: exist.tex

ConfidenceProgramDetectionMatch TypeSupport
100% dexvert LaTeX Document (document/latex) magic Supported
1% dexvert Text File (text/txt) fallback Supported
100% file LaTeX document text default
99% file LaTeX document, ASCII text, with CR line terminators default
100% checkBytes Printable ASCII default
100% perlTextCheck Likely Text (Perl) default
100% siegfried fmt/281 LaTeX (Subdocument) default
100% detectItEasy Format: plain text[CR] default (weak)


id metadata
keyvalue
macFileType[TEXT]
macFileCreator[ttxt]



hex view
+--------+-------------------------+-------------------------+--------+--------+
|00000000| 5c 73 65 63 74 69 6f 6e | 7b 65 78 69 73 74 20 2d |\section|{exist -|
|00000010| 2d 2d 20 54 65 73 74 20 | 66 6f 72 20 61 6e 20 61 |-- Test |for an a|
|00000020| 72 67 75 6d 65 6e 74 7d | 0d 5c 6c 61 62 65 6c 7b |rgument}|.\label{|
|00000030| 66 6e 3a 65 78 69 73 74 | 7d 0d 5c 69 6e 64 65 78 |fn:exist|}.\index|
|00000040| 7b 65 78 69 73 74 28 29 | 7d 0d 5c 69 6e 64 65 78 |{exist()|}.\index|
|00000050| 7b 74 65 73 74 69 6e 67 | 20 66 6f 72 20 61 6e 20 |{testing| for an |
|00000060| 61 72 67 75 6d 65 6e 74 | 7d 0d 5c 69 6e 64 65 78 |argument|}.\index|
|00000070| 7b 61 72 67 75 6d 65 6e | 74 21 74 65 73 74 69 6e |{argumen|t!testin|
|00000080| 67 20 66 6f 72 7d 0d 5c | 62 65 67 69 6e 7b 72 61 |g for}.\|begin{ra|
|00000090| 69 6c 7d 0d 45 78 69 73 | 74 20 3a 20 27 65 78 69 |il}.Exis|t : 'exi|
|000000a0| 73 74 27 20 27 28 27 20 | 28 20 53 63 61 6c 61 72 |st' '(' |( Scalar|
|000000b0| 20 7c 20 4d 61 74 72 69 | 78 20 7c 20 4c 69 73 74 | | Matri|x | List|
|000000c0| 20 7c 20 53 74 72 69 6e | 67 29 20 27 29 27 20 3b | | Strin|g) ')' ;|
|000000d0| 0d 5c 65 6e 64 7b 72 61 | 69 6c 7d 0d 0d 5c 76 65 |.\end{ra|il}..\ve|
|000000e0| 72 62 2b 65 78 69 73 74 | 2b 20 69 73 20 61 20 66 |rb+exist|+ is a f|
|000000f0| 75 6e 63 74 69 6f 6e 20 | 74 68 61 74 20 74 65 73 |unction |that tes|
|00000100| 74 73 20 77 68 65 74 68 | 65 72 20 69 74 73 20 61 |ts wheth|er its a|
|00000110| 72 67 75 6d 65 6e 74 20 | 69 73 20 61 63 74 75 61 |rgument |is actua|
|00000120| 6c 6c 79 0d 61 20 6c 65 | 67 69 74 69 6d 61 74 65 |lly.a le|gitimate|
|00000130| 20 76 61 72 69 61 62 6c | 65 20 6f 72 20 66 75 6e | variabl|e or fun|
|00000140| 63 74 69 6f 6e 2e 20 49 | 66 20 74 68 65 20 61 72 |ction. I|f the ar|
|00000150| 67 75 6d 65 6e 74 20 65 | 78 69 73 74 73 2c 20 74 |gument e|xists, t|
|00000160| 68 65 6e 20 5c 76 65 72 | 62 2b 65 78 69 73 74 2b |hen \ver|b+exist+|
|00000170| 0d 72 65 74 75 72 6e 73 | 20 24 31 24 2c 20 6f 72 |.returns| $1$, or|
|00000180| 20 74 72 75 65 20 69 66 | 20 79 6f 75 20 70 72 65 | true if| you pre|
|00000190| 66 65 72 2c 20 61 6e 64 | 20 72 65 74 75 72 6e 73 |fer, and| returns|
|000001a0| 20 24 30 24 2c 20 6f 72 | 20 66 61 6c 73 65 2c 20 | $0$, or| false, |
|000001b0| 69 66 20 74 68 65 0d 61 | 72 67 75 6d 65 6e 74 20 |if the.a|rgument |
|000001c0| 64 6f 65 73 6e 27 74 20 | 65 78 69 73 74 2e 0d 0d |doesn't |exist...|
|000001d0| 4e 6f 74 65 20 74 68 61 | 74 20 79 6f 75 20 63 61 |Note tha|t you ca|
|000001e0| 6e 27 74 20 70 61 73 73 | 20 61 20 63 6f 6e 73 74 |n't pass| a const|
|000001f0| 61 6e 74 20 76 61 6c 75 | 65 20 61 73 20 61 6e 20 |ant valu|e as an |
|00000200| 61 72 67 75 6d 65 6e 74 | 2c 20 61 6e 64 20 70 61 |argument|, and pa|
|00000210| 73 73 69 6e 67 0d 61 6e | 20 61 72 67 75 6d 65 6e |ssing.an| argumen|
|00000220| 74 20 74 68 61 74 20 68 | 61 73 20 65 6e 6f 75 67 |t that h|as enoug|
|00000230| 68 20 62 72 61 63 6b 65 | 74 73 20 74 6f 20 6c 6f |h bracke|ts to lo|
|00000240| 6f 6b 20 6c 69 6b 65 20 | 61 20 66 75 6e 63 74 69 |ok like |a functi|
|00000250| 6f 6e 2c 20 62 75 74 0d | 69 73 6e 27 74 20 72 65 |on, but.|isn't re|
|00000260| 61 6c 6c 79 20 61 20 66 | 75 6e 63 74 69 6f 6e 2c |ally a f|unction,|
|00000270| 20 67 69 76 65 73 20 61 | 6e 20 65 72 72 6f 72 20 | gives a|n error |
|00000280| 6d 65 73 73 61 67 65 2e | 20 20 54 68 69 73 20 69 |message.| This i|
|00000290| 73 20 63 61 75 73 65 64 | 20 62 79 0d 5c 52 4c 61 |s caused| by.\RLa|
|000002a0| 42 5c 20 6e 6f 74 20 62 | 65 69 6e 67 20 61 62 6c |B\ not b|eing abl|
|000002b0| 65 20 74 6f 20 65 76 61 | 6c 75 61 74 65 20 74 68 |e to eva|luate th|
|000002c0| 65 20 66 75 6e 63 74 69 | 6f 6e 2e 0d 0d 49 6e 20 |e functi|on...In |
|000002d0| 67 65 6e 65 72 61 6c 2c | 20 79 6f 75 20 73 68 6f |general,| you sho|
|000002e0| 75 6c 64 20 62 65 20 75 | 73 69 6e 67 20 74 68 69 |uld be u|sing thi|
|000002f0| 73 20 66 75 6e 63 74 69 | 6f 6e 20 69 6e 20 67 65 |s functi|on in ge|
|00000300| 6e 65 72 61 6c 20 70 75 | 72 70 6f 73 65 0d 75 73 |neral pu|rpose.us|
|00000310| 65 72 2d 64 65 66 69 6e | 65 64 20 66 75 6e 63 74 |er-defin|ed funct|
|00000320| 69 6f 6e 73 20 74 6f 20 | 6d 61 6b 65 20 73 75 72 |ions to |make sur|
|00000330| 65 20 61 6c 6c 20 74 68 | 65 20 6e 65 63 63 65 73 |e all th|e necces|
|00000340| 73 61 72 79 20 61 72 67 | 75 6d 65 6e 74 73 20 61 |sary arg|uments a|
|00000350| 72 65 0d 70 72 65 73 65 | 6e 74 2c 20 61 6e 64 20 |re.prese|nt, and |
|00000360| 74 6f 20 70 72 6f 76 69 | 64 65 20 64 65 66 61 75 |to provi|de defau|
|00000370| 6c 74 73 20 61 73 20 61 | 70 70 72 6f 70 72 69 61 |lts as a|ppropria|
|00000380| 74 65 2e 0d 0d 0d 5c 70 | 61 72 61 67 72 61 70 68 |te....\p|aragraph|
|00000390| 7b 45 78 61 6d 70 6c 65 | 7d 0d 5c 69 6e 64 65 78 |{Example|}.\index|
|000003a0| 7b 65 78 61 6d 70 6c 65 | 20 6f 66 20 65 78 69 73 |{example| of exis|
|000003b0| 74 28 29 7d 0d 5c 69 6e | 64 65 78 7b 65 78 69 73 |t()}.\in|dex{exis|
|000003c0| 74 28 29 21 65 78 61 6d | 70 6c 65 7d 0d 5c 62 65 |t()!exam|ple}.\be|
|000003d0| 67 69 6e 7b 76 65 72 62 | 61 74 69 6d 7d 0d 3e 20 |gin{verb|atim}.> |
|000003e0| 77 68 6f 28 29 0d 65 70 | 73 20 20 70 69 20 20 20 |who().ep|s pi |
|000003f0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 0d | | .|
|00000400| 3e 20 65 78 69 73 74 28 | 65 70 73 29 0d 20 20 20 |> exist(|eps). |
|00000410| 20 20 20 20 20 31 0d 3e | 20 65 78 69 73 74 28 73 | 1.>| exist(s|
|00000420| 69 6e 29 0d 20 20 20 20 | 20 20 20 20 31 0d 3e 20 |in). | 1.> |
|00000430| 65 78 69 73 74 28 73 69 | 6e 28 32 29 29 0d 20 20 |exist(si|n(2)). |
|00000440| 20 20 20 20 20 20 31 0d | 3e 20 65 78 69 73 74 28 | 1.|> exist(|
|00000450| 32 29 0d 72 6c 61 62 3a | 20 69 6e 76 61 6c 69 64 |2).rlab:| invalid|
|00000460| 20 61 72 67 75 6d 65 6e | 74 20 74 6f 20 65 78 69 | argumen|t to exi|
|00000470| 73 74 2c 0d 5c 65 6e 64 | 7b 76 65 72 62 61 74 69 |st,.\end|{verbati|
|00000480| 6d 7d 0d 0d 53 65 65 20 | 61 6c 73 6f 3a 20 50 61 |m}..See |also: Pa|
|00000490| 67 65 7e 5c 70 61 67 65 | 72 65 66 7b 66 6e 3a 77 |ge~\page|ref{fn:w|
|000004a0| 68 61 74 7d 20 5c 76 65 | 72 62 2b 77 68 61 74 28 |hat} \ve|rb+what(|
|000004b0| 29 2b 2c 0d 50 61 67 65 | 7e 5c 70 61 67 65 72 65 |)+,.Page|~\pagere|
|000004c0| 66 7b 66 6e 3a 77 68 6f | 7d 20 5c 76 65 72 62 2b |f{fn:who|} \verb+|
|000004d0| 77 68 6f 28 29 2b 2e 0d | 0d 5c 6e 65 77 70 61 67 |who()+..|.\newpag|
|000004e0| 65 0d 0d 0d 0d 0d 0d 0d | |e.......| |
+--------+-------------------------+-------------------------+--------+--------+