/ Celestin Apprentice 4 / Apprentice-Release4.iso / Languages / RLaB 1.18c / manual / read.tex

< prev

next >

MacOS 8.1

Win98

DOS

view JSON data

view as text

+--------+-------------------------+-------------------------+--------+--------+
|00000000| 5c 73 65 63 74 69 6f 6e | 7b 72 65 61 64 20 2d 2d |\section|{read --|
|00000010| 2d 20 46 69 6c 65 20 52 | 65 61 64 7d 0d 5c 6c 61 |- File R|ead}.\la|
|00000020| 62 65 6c 7b 66 6e 3a 72 | 65 61 64 7d 0d 5c 69 6e |bel{fn:r|ead}.\in|
|00000030| 64 65 78 7b 72 65 61 64 | 28 29 7d 0d 5c 69 6e 64 |dex{read|()}.\ind|
|00000040| 65 78 7b 66 69 6c 65 20 | 72 65 61 64 7d 0d 5c 69 |ex{file |read}.\i|
|00000050| 6e 64 65 78 7b 76 61 72 | 69 61 62 6c 65 73 21 72 |ndex{var|iables!r|
|00000060| 65 61 64 69 6e 67 20 66 | 72 6f 6d 20 61 20 66 69 |eading f|rom a fi|
|00000070| 6c 65 7d 0d 5c 62 65 67 | 69 6e 7b 72 61 69 6c 7d |le}.\beg|in{rail}|
|00000080| 0d 52 65 61 64 20 3a 20 | 27 72 65 61 64 27 20 27 |.Read : |'read' '|
|00000090| 28 27 20 53 74 72 69 6e | 67 20 27 29 27 20 3b 0d |(' Strin|g ')' ;.|
|000000a0| 5c 65 6e 64 7b 72 61 69 | 6c 7d 0d 0d 5c 76 65 72 |\end{rai|l}..\ver|
|000000b0| 62 2b 72 65 61 64 2b 20 | 69 73 20 61 20 66 75 6e |b+read+ |is a fun|
|000000c0| 63 74 69 6f 6e 20 74 68 | 61 74 20 61 6c 6c 6f 77 |ction th|at allow|
|000000d0| 73 20 79 6f 75 20 74 6f | 20 72 65 61 64 20 69 6e |s you to| read in|
|000000e0| 20 76 61 72 69 61 62 6c | 65 73 20 66 72 6f 6d 20 | variabl|es from |
|000000f0| 61 0d 66 69 6c 65 2e 20 | 20 54 68 65 20 73 74 72 |a.file. | The str|
|00000100| 69 6e 67 20 61 72 67 75 | 6d 65 6e 74 20 73 70 65 |ing argu|ment spe|
|00000110| 63 69 66 69 65 73 20 74 | 68 65 20 66 69 6c 65 20 |cifies t|he file |
|00000120| 74 6f 20 72 65 61 64 20 | 66 72 6f 6d 2e 20 20 41 |to read |from.  A|
|00000130| 6c 6c 20 74 68 65 0d 76 | 61 72 69 61 62 6c 65 73 |ll the.v|ariables|
|00000140| 20 74 68 61 74 20 61 72 | 65 20 73 74 6f 72 65 64 | that ar|e stored|
|00000150| 20 69 6e 20 74 68 65 20 | 66 69 6c 65 20 61 72 65 | in the |file are|
|00000160| 20 72 65 61 64 20 69 6e | 2c 20 6f 76 65 72 77 72 | read in|, overwr|
|00000170| 69 74 69 6e 67 20 61 6e | 79 0d 65 78 69 73 74 69 |iting an|y.existi|
|00000180| 6e 67 20 76 61 72 69 61 | 62 6c 65 73 20 77 69 74 |ng varia|bles wit|
|00000190| 68 20 74 68 65 20 73 61 | 6d 65 20 6e 61 6d 65 2e |h the sa|me name.|
|000001a0| 20 20 54 68 65 20 66 69 | 6c 65 20 69 73 20 63 6c |  The fi|le is cl|
|000001b0| 6f 73 65 64 20 61 66 74 | 65 72 20 69 74 0d 68 61 |osed aft|er it.ha|
|000001c0| 73 20 62 65 65 6e 20 72 | 65 61 64 20 66 72 6f 6d |s been r|ead from|
|000001d0| 2e 20 20 54 68 69 73 20 | 66 75 6e 63 74 69 6f 6e |.  This |function|
|000001e0| 20 72 65 74 75 72 6e 73 | 20 24 31 24 20 69 73 20 | returns| $1$ is |
|000001f0| 74 68 65 20 72 65 61 64 | 20 73 75 63 63 65 65 64 |the read| succeed|
|00000200| 73 2e 0d 0d 54 68 65 20 | 66 6f 72 6d 61 74 20 6f |s...The |format o|
|00000210| 66 20 74 68 65 20 66 69 | 6c 65 20 69 73 20 71 75 |f the fi|le is qu|
|00000220| 69 74 65 20 73 70 65 63 | 69 66 69 63 2c 20 61 6e |ite spec|ific, an|
|00000230| 64 20 69 74 20 69 73 20 | 69 6e 74 65 6e 64 65 64 |d it is |intended|
|00000240| 20 74 68 61 74 20 74 68 | 69 73 0d 66 75 6e 63 74 | that th|is.funct|
|00000250| 69 6f 6e 20 62 65 20 75 | 73 65 64 20 77 69 74 68 |ion be u|sed with|
|00000260| 20 74 68 65 20 5c 76 65 | 72 62 2b 77 72 69 74 65 | the \ve|rb+write|
|00000270| 2b 20 66 75 6e 63 74 69 | 6f 6e 2e 20 20 54 72 79 |+ functi|on.  Try|
|00000280| 69 6e 67 20 74 6f 20 63 | 72 65 61 74 65 20 61 0d |ing to c|reate a.|
|00000290| 66 69 6c 65 20 74 68 61 | 74 20 63 61 6e 20 62 65 |file tha|t can be|
|000002a0| 20 5c 76 65 72 62 2b 72 | 65 61 64 2b 20 66 72 6f | \verb+r|ead+ fro|
|000002b0| 6d 20 69 73 20 66 72 61 | 75 67 68 74 20 77 69 74 |m is fra|ught wit|
|000002c0| 68 20 64 61 6e 67 65 72 | 2e 20 20 49 66 20 69 74 |h danger|.  If it|
|000002d0| 20 69 73 0d 65 73 73 65 | 6e 74 69 61 6c 2c 20 49 | is.esse|ntial, I|
|000002e0| 20 73 75 67 67 65 73 74 | 20 75 73 69 6e 67 20 5c | suggest| using \|
|000002f0| 76 65 72 62 2b 77 72 69 | 74 65 2b 20 74 6f 20 63 |verb+wri|te+ to c|
|00000300| 72 65 61 74 65 20 6f 6e | 65 20 73 69 6d 69 6c 61 |reate on|e simila|
|00000310| 72 2c 20 61 6e 64 0d 74 | 68 65 6e 20 65 64 69 74 |r, and.t|hen edit|
|00000320| 69 6e 67 20 61 73 20 6c | 69 74 74 6c 65 20 61 73 |ing as l|ittle as|
|00000330| 20 6e 65 63 65 73 73 61 | 72 79 2e 0d 0d 0d 5c 70 | necessa|ry....\p|
|00000340| 61 72 61 67 72 61 70 68 | 7b 45 78 61 6d 70 6c 65 |aragraph|{Example|
|00000350| 7d 0d 5c 69 6e 64 65 78 | 7b 65 78 61 6d 70 6c 65 |}.\index|{example|
|00000360| 20 6f 66 20 72 65 61 64 | 28 29 7d 0d 5c 69 6e 64 | of read|()}.\ind|
|00000370| 65 78 7b 72 65 61 64 28 | 29 21 65 78 61 6d 70 6c |ex{read(|)!exampl|
|00000380| 65 7d 0d 5c 62 65 67 69 | 6e 7b 76 65 72 62 61 74 |e}.\begi|n{verbat|
|00000390| 69 6d 7d 0d 44 75 6d 6d | 79 20 45 78 61 6d 70 6c |im}.Dumm|y Exampl|
|000003a0| 65 0d 5c 65 6e 64 7b 76 | 65 72 62 61 74 69 6d 7d |e.\end{v|erbatim}|
|000003b0| 0d 0d 53 65 65 20 61 6c | 73 6f 3a 20 50 61 67 65 |..See al|so: Page|
|000003c0| 7e 5c 70 61 67 65 72 65 | 66 7b 66 6e 3a 63 6c 6f |~\pagere|f{fn:clo|
|000003d0| 73 65 7d 20 5c 76 65 72 | 62 2b 63 6c 6f 73 65 28 |se} \ver|b+close(|
|000003e0| 29 2b 2c 0d 50 61 67 65 | 7e 5c 70 61 67 65 72 65 |)+,.Page|~\pagere|
|000003f0| 66 7b 66 6e 3a 72 65 61 | 64 6d 7d 20 5c 76 65 72 |f{fn:rea|dm} \ver|
|00000400| 62 2b 72 65 61 64 6d 28 | 29 2b 2c 0d 50 61 67 65 |b+readm(|)+,.Page|
|00000410| 7e 5c 70 61 67 65 72 65 | 66 7b 66 6e 3a 77 72 69 |~\pagere|f{fn:wri|
|00000420| 74 65 7d 20 5c 76 65 72 | 62 2b 77 72 69 74 65 28 |te} \ver|b+write(|
|00000430| 29 2b 2c 0d 50 61 67 65 | 7e 5c 70 61 67 65 72 65 |)+,.Page|~\pagere|
|00000440| 66 7b 66 6e 3a 77 72 69 | 74 65 6d 7d 20 5c 76 65 |f{fn:wri|tem} \ve|
|00000450| 72 62 2b 77 72 69 74 65 | 6d 28 29 2b 2e 0d 0d 5c |rb+write|m()+...\|
|00000460| 6e 65 77 70 61 67 65 0d | 0d                      |newpage.|.       |
+--------+-------------------------+-------------------------+--------+--------+