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XNÉIO 0 1 ° XNÉCT 0 1.000000000000011E²13 ° XCÉFC 1 6 .,*0_² ° XNÉRL 0 16807 ° XCÉPR 0 ° XCÉLX 1 5 TEACH ° NATTS 2 3 9 1 1001 1996 6 3 14 23 23 81 1 1001 1996 6 3 14 23 3 22 1 ° X 1001 1996 6 3 14 23 17 78 ° XNC210 0 0 ° XND210 1 0 ° XAD211╜('DROP')('FUNCTION') ° XNDAT 2 3 3 1 2 3 4 5 6 7 8 9 ° *(1991 11 11 8 26 35 408) ° FDISPLAY ÉFX 'D╜S DISPLAY A;ÉIO;R;C;HL;HC;HT;HB;VL;VB;V;W;N;B' ° 'Σ DISPLAY A GENERAL ARRAY IN PICTORIAL FORM' ° 'Σ NORMAL CALL IS MONADIC. DYADIC CALL USED ONLY IN' ° 'Σ RECURSION TO SPECIFY DISPLAY RANK, SHAPE, AND DEPTH.' 'ÉIO╜0' ° '»(0=ÉNC ''S'')/''S╜µA''' 'R╜╞µ,S Σ PSEUDO RANK.' ° 'C╜''┐┌└┘'' Σ UR, UL, LL, AND LR CORNERS.' ° 'HL╜''─'' Σ HORIZONTAL LINE.' ° 'HC╜HL,''Θ╕'',HL,''~+ε'' Σ HORIZONTAL BORDERS.' ° 'HT╜HC[(0<R)⌡1+0<╞²1╞,S]' 'ΣW╜,0╧■╞0µΓ(1⌐µA)╞A' ° 'HB╜HC[3+3╛(''2⌡~A╧«A'' ÉEA ''1+╞ε0⌡(1⌐⌡/µA)╞,A'')+3⌡1<µµS]' ° 'VL╜''│'' Σ VERTICAL LINE.' ° 'VB╜VL,''Φ╟'' Σ VERTICAL BORDER.' ° 'V╜VB[(1<R)⌡1+0<²1╞²1╟,S]' ° '»(0εµA)/''A╜(1⌐µA)µΓ╞A'' Σ SHOW PROTOTYPE OF EMPTIES.' ° '╕(1<╧A)/GEN' '╕(2<µµA)/D3' ° 'D╜«A Σ SIMPLE ARRAYS.' 'W╜1╞µD╜(²2╞1 1,µD)µD' ° 'N╜²1+1╟µD' '╕(0=µµA)/SS' ° 'D╜(C[1],V,((W-1)µVL),C[2]),((HT,NµHL),[0]D,[0]HB,NµHL),C[0],(WµVL),C[ ° 3]' '╕0' 'SS:HB╜((0 '' '')=╞0µΓA)/'' -''' ° 'D╜'' '',('' '',[0]D,[0]HB,Nµ'' ''),'' ''' '╕0' ° 'GEN:D╜«DISPLAY■A Σ ENCLOSED ...' 'N╜Dδ.⌠'' ''' ° 'D╜(Nδ~1ΦN)≡D' 'D╜(δ≡~'' ''╤D)/D' 'D╜((1,µS)µS)DISPLAY D' ° '╕(2≥µ,S)╟D3E,0' 'D3:D╜0 ²1╟0 1╟«ΓA Σ MULT-DIMENSIONAL ...' ° 'W╜1╞µD' 'N╜²1+1╟µD' ° 'D╜(C[1],V,((W-1)µVL),C[2]),((HT,NµHL),[0]D,[0]HB,NµHL),C[0],(WµVL),C[ ° 3]' 'D3E:N╜²2+µ,S' ° X 'V╜C[Nµ1],[0]VB[1+0<²2╟,S],[0](((²3+╞µD),N)µVL),[0]C[Nµ2]' 'D╜V,D' ° *(1991 11 11 8 26 36 412) ° FGO ÉFX 'GO;b;e;t' 'Σ Expression driver' 'L0:b╜e╜''''' 'æ╜'' ''' ° 't╜æ' '╕(^/'' ''=t)/L0' '╕((^/'')OFF ''=5╞6╟t)doif ''exit'')/0' ° '╕(('':''εt)doif ''b╜evaldd (+/^\'''' ''''=t)╟t'')/L0' ° '''e╜ÉEM'' ÉEA t' '╕(0=µ,e)/L0' '╕b/L0' ° '''This is not a valid APL2 expression''' 'æ╜''*''' ° X '╕(''?''⌠╞1╟æ)/L0' 'e' '╕L0' ° CLIST 2 3 31 ONE TWO ° X THREE ° XCONE 1 16 CHARACTER STRING ° XNRC 0 0 ° *(1995 4 23 14 14 6 304) ° FSVOFFER ÉFX 'DC╜PID SVOFFER SV' 'SV╜(²2╞1 1,µSV)µSV╜πSV' ° '╕(2=ÉNC ''PID'')/DYADIC' 'DC╜ÉSVO SV ╪ ╕0' ° 'DYADIC:╕(1^.⌠DC╜PID ÉSVO SV)/END' 'ÉSVE╜15' ° 'CHECK:╕(1^.⌠DC╜ÉSVO SV)/END' '╕(0⌠ÉSVE)/CHECK' ° X 'END:SV╜1 0 1 0 ÉSVC SV' ° *(1995 9 25 14 7 42 448) ° FSVOPAIR ÉFX '≈_DC╜≈_PID SVOPAIR ≈_SV;≈_CV' ° '≈_SV╜(²2╞1 1,µ≈_SV)µ≈_SV╜π≈_SV' '╕(2=ÉNC ''≈_PID'')/≈_DYADIC' ° '≈_DC╜ÉSVO ≈_SV' '╕0' '≈_DYADIC:' '≈_CV╜(-+/^\Φ≈_SV='' '')Φ≈_SV' ° '≈_CV╜(-+/^\Φ≈_CV⌠'' '')Φ≈_CV' '≈_CV╜≈_CV[;ÉIO]=''C''' ° '╕(1^.⌠≈_CV/≈_DC╜≈_PID ÉSVO ≈_SV)/≈_END' 'ÉSVE╜15' '≈_CHECK:' ° '╕(1^.⌠≈_CV/≈_DC╜ÉSVO ≈_SV)/≈_END' '╕(0⌠ÉSVE)/≈_CHECK' '≈_END:' ° X '≈_CV╜1 0 1 0 ÉSVC ≈_CV≡≈_SV' ° *(1996 5 30 14 16 50 524) ° FTEACH ÉFX 'TEACH;B' 'Σ Copyright Z V Jizba 1991; all rights reserved' ° 'copyright' 'initialize' 'TEACH1 Σ Dealing with (external) files' ° '''There are two AP''''s that deal with files. AP210 allows you to''' ° '''process any file that you can access. Learning how to use this''' ° '''AP is somewhat involved.'',r' ° '''AP211 is designed to store and retrieve named APL2 objects. The''' ° '''use of this AP is easy to learn. If you wish to skip the portion''' ° 'B╜3⌠''yY''∞╞get ''dealing with AP210, enter Yes here: ''' 'do' ° '╕B/L1' 'TEACH2 Σ Auxilliary Processo 210 -- External files' ° 'TEACH3 Σ AP210 Control variable' 'TEACH4 Σ AP210 Command mode' ° 'TEACH5 Σ Sample file TEST210' 'TEACH6 Σ AP210 Control Subcommands' ° 'TEACH7 Σ AP210 Control Subcommands (continued)' ° 'TEACH8 Σ AP210 Return Codes' ° 'L1:TEACH9 Σ AP211 Storing and retrieving APL2 objects' ° 'TEACH10 Σ Reading and accessing AP211 data' ° X 'TEACH11 Σ Final comments on AP211' ° *(1996 6 3 14 27 41 428) ° FTEACH1 ÉFX 'TEACH1' 'Σ File auxilliary processor (AP210)' ° '''In the previous lesson we described a simple Auxilliary Processor, ° the''' ° '''AP100. It''''s purpose is to be able to enter OS2/DOS commands from ° within''' ° '''APL2. We also studied AP101, the Stack Processor. Using AP 101 we c ° an''' ° '''issue System Commands from within APL2. In this lesson we will''' ° '''describe Auxilliary Processors 210 and 211. These processors provid ° e''' '''the tools for communicating with the OS@ (DOS) file system.''' ° 'do' ° '''When dealing with files, one has to be able to specify one of sever ° al''' '''functions:'',r' ''' a. define a new file''' ° ''' b. write a record into the file''' ° ''' c. read a record from a file''' ° ''' d. remove a record from a file''' ''' e. rename a file''' ° ''' f. erase a file'',r' ° '''The information about what specific function is to be performed is' ° '' ° '''not always sufficient. To deal with items b. c. and d., it is also' ° '' ° '''necessary to specify a location for data to be stored or retrieved. ° '',r' ° '''If we think of the process of dealing with external files as if it' ° '' ° '''were a function, then it would be an ambivalent one. The right''' ° '''argument would contain the file process to be implemented, and the' ° '' ° '''left optional argument would specify the data to be stored, or the' ° '' ° '''name of a variable to contain the data to be retrieved. The functio ° n''' ° '''would return a code giving the success or failure of the operation. ° X''' 'end' ° *(1996 4 23 13 23 59 552) ° FTEACH10 ÉFX 'TEACH10;D211;T' 'Σ Reading and accessing AP211 data' ° 'T╜211 SVOFFER ''D211''' 'D211╜''DROP'' ''FUNCTION''' ° 'D211╜''CREATE'' ''FUNCTION'' ╪ T╜D211' ° '''Before data can be entered to (or read from) the file, it has to be ° ''' '''opened with the USE command'',r' ° 'show ''D211╜''''USE'''' ''''FUNCTION'''''' ''D211''' ° '''Note that in addition to the Return Code, we also get a second''' ° '''element, namely the record length assigned to the file.'',r' ° '''Once a 211 type file has been opened, there are four types of''' ° '''operations that make sense. These are'',r' ° ''' GET get an APL2 object from the file''' ° ''' SET place an APL2 object into the file''' ° ''' ERASE erase an APL2 object from the file''' ° ''' LIST list the names of APL2 objects in the file'',r' 'do' ° '''The SET command is of the form'',r' ° ''' D211╜''''SET'''' ''''name'''' APL2-object'',r' ° '''Note that the third element must be a scalar element of the three'' ° ' ° '''element vector. That means that normally, the APL2 object must be'' ° ' '''enclosed.'',r' ° '''The following example shows a valid entry because the right argumen ° t is''' '''a valid three element nested vector'',r' ° 'show ''D211╜''''SET'''' ''''ONE'''' ''''TEST DATA'''''' ''D211''' ° '''Again, the return code of 0 means that the SET process was successf ° ul.''' 'do' ° '''In the next example we wish to store an array containing the canoni ° cal''' ° '''representation of function "date". This array must be enclosed so t ° hat the''' ° '''argument to be assigned to D211 is a three element vector.'',r' ° 'show ''D211╜''''SET'''' ''''TWO'''',ΓÉCR ''''date'''''' ''D211''' ° '''Here is another APL2 data type to be stored'',r' ° 'show ''D211╜''''SET'''' ''''THREE'''',Γ3 3µ∞9'' ''D211''' ° '''We have now stored three APL2 objects, namely ONE, TWO, and THREE.' ° '' ° '''Suppose we find that object ONE is no longer valid, and we wish to' ° '' ° '''replace it by another object, say the string ''''ANOTHER TEST VECTO ° R''''''' '''This can be done simply by entering'',r' ° 'show ''D211╜''''SET'''' ''''ONE'''' ''''ANOTHER TEST VECTOR'''''' ''D ° 211''' ° '''To retrieve an APL2 object previously stored, we use command GET'', ° r' ° 'show ''D211╜''''GET'''' ''''THREE'''''' ''THREE╜2πÉ╜D211'' ''DISPLAY ° THREE''' ° '''Since D211 can be referenced only once, it is a good idea to assign ° ''' ° '''it immediately to a normal APL2 variable. Note also that the conten ° ts''' ° '''of D211 is a two element vector. The first element of that vector i ° s''' ° '''the Return Code, and the second element is the APL2 object that has ° ''' '''been retrieved.''' 'do' ° '''To see what named objects reside in the file, we use command LIST'' ° ,r' 'show ''D211╜''''LIST'''' ''''NAMES'''''' ''DISPLAY LIST╜D211''' ° '''It is also possible to obtain a table listing three numeric items'' ° ,r' ° ''' The number of fixed length records needed to store the APL2 obj ° ect''' ''' The user ID (default is 1001)''' ° ''' The time stamp of the last update of the APL2 object'',r' ° 'show ''D211╜''''LIST'''' ''''ATTS'''''' ''DISPLAY ATTS╜D211''' ° '''Command LIST NAMES tells the contents of an AP211 file. What happen ° s''' ° '''when command GET is issued for an entry not on that list. Recall th ° at''' '''for a valid entry, D211 contains a two element vector'',r' ° 'show ''D211╜''''GET'''' ''''ONE'''''' ''DISPLAY D211''' ° '''For an invalid entry, the result is numeric return code'',r' ° 'show ''D211╜''''GET'''' ''''FOUR'''''' ''DISPLAY D211''' ° '''When using the GET command it may be generally useful to take advan ° tage''' '''of the multiple specification feature of APL2'',r' ° 'show ''D211╜''''GET'''' ''''THREE'''''' ''(RC DAT)╜D211'' ''RC'' ''DI ° SPLAY DAT''' ° '''Finally, one may require the removal of specific objects from the'' ° ' '''file. The command ERASE will do that'',r' ° 'show ''D211╜''''LIST'''' ''''NAMES'''''' ''D211'' ''D211╜''''ERASE''' ° ' ''''ONE''''''' ° 'show ''D211'' ''D211╜''''LIST'''' ''''NAMES'''''' ''D211''' ° '''Although Shared Variable 211 can be retracted with the ÉSVR Command ° ,''' ° '''one need not take that step. If more than one file is to be process ° ed,''' ° '''the command RELEASE has the effect of closing a file that has been' ° '' '''previously opened with the USE command'',r' ° X 'show ''D211╜''''RELEASE'''''' ''D211''' 'end' ° *(1996 4 23 13 24 24 416) ° FTEACH11 ÉFX 'TEACH11' 'Σ Final comments on AP211' ° '''In summary, AP211 is APL-like, is simple to use, and provides a fas ° t''' ° '''and efficient way to store APL2 objects. As the limitations on the' ° '' ° '''size of APL2 workspaces are gradually removed, one may question the ° ''' ° '''desirability of having a second level of storage for APL2 data. It ° is''' ° '''possible that for many if not most applications one can get along w ° ith''' ° '''a single workspace holding every APL2 object. Nevertheless there wi ° ll''' ° '''invariably arise situations where this strategy is not the best.''' ° 'do' ° '''There are many such possible applications of AP211. Here are some o ° f''' '''the more obvious ones:'',r' ° ''' Seldom used APL2 utilities can be stored in file UTILITY''' ° ''' Documentation or HELP files can be stored in file HELP''' ° ''' Documentation can be placed in file BLUEPRINT''' ° ''' Seldom used subroutines of complex applications''' ° ''' Semantic nets or other AI structures''' ° ''' Data bases of all kinds requiring access by name'',r' 'do' ° '''In a later lesson we will show some specific examples of the usage ° of''' '''AP211.''' ° '''Before we leave this lesson, we should discard file FUNCTION'',r' ° X 'show ''D211╜''''DROP'''' ''''FUNCTION''''''' 'end' ° *(1996 5 30 14 19 47 524) ° FTEACH2 ÉFX 'TEACH2;C210;D210;T' 'Σ Control and data variables' ° '''AUXILLIARY PROCESSOR 210'',r' ° '''In the previous lesson we invoked function SVOFFER to activate the' ° '' ° '''shared variable named in its right argument. For Auxilliary Process ° or''' ° '''210, one shared variable is insufficient to deal with the requireme ° nts''' ° '''associated with processing of external files. To deal with this, we ° ''' ° '''will use the IBM supplied function SVOPAIR. At this point it might' ° '' '''be useful to review the use of the ÉSVO System Function.''' 'do' ° '''When the ÉSVO command is given, the right argument allows not one, ° but''' ° '''two or more names to be associated with a specific AP. If more than ° ''' ° '''one such variable is needed, the names must in some way be similar, ° so''' ° '''that the AP will be able to recognize the existence of the close ti ° es''' '''connecting these labels.'',r' ° '''Typically one of the variables is used to control the process, and' ° '' ° '''another one is used to contain the data. Therefore, the first varia ° ble''' ° '''must begin with the letter C (for CONTROL). Not surprisingly, the'' ° ' ° '''second variable must begin with the letter D (for DATA). The remain ° der''' ° '''of the label is arbitrary (subject to APL2 naming conventions),''' ° '''provided the subscript is identical for both.''' 'do' ° '''So if we name the control variable C210, then the data variable has ° to''' '''have the name D210.'',r' 'T╜210 SVOPAIR ''C210'' ''D210''' ° ''' 210 ÉSVO■ ''''C210'''' ''''D210'''''',r,''1 1''' ° 'show ''ÉSVO■ ''''C210'''' ''''D210''''''' ° '''Just as in AP100 and AP101, the full COUPLING requires a second iss ° ue''' ° '''of ÉSVO. Note, however, that D210 (the varable associated with data ° )''' ° '''retains its coupling of one. Why? Because no data transfer is possi ° Xble''' '''until a suitable CONTROL command has been set.''' 'TEACH2A' ° *(1996 4 25 14 1 16 304) ° FTEACH2A ÉFX 'TEACH2A;T' 'Σ C210 and D210 as variables' '''''' 'do' ° '''Although C210 and D210 are known to APL2 as "variables"'',r' ° 'show ''ÉNC■ ''''C210'''' ''''D210''''''' ° '''at this point they are still undefined. Any reference to them will' ° '' '''return a VALUE ERROR.'',r' 'T╜0 0 0 0 ÉSVC ''C210''' ° '''(if your screen FREEZES at the next example, do an INTERRUPT, becau ° se''' '''your Shared Variable Control has been set to 1.)''' ° '0 show ''C210''' ° '''In general, shared variables MUST be assigned (or referenced) in a' ° '' ° '''specific sequence. Before we can discuss that sequence, it will be' ° '' '''useful to discuss the scope of Auxilliary Processor 210.''' 'do' ° '''However, before we get into details on the use of AP210, you may''' ° '''wish to study function SVOPAIR. If you do, enter YES at the next''' ° '''prompt.''' ° '╕(~(╞ans ''Do you wish to study function SVOPAIR?'')ε''Yy'')/0' ° '''Function "svopair" is a copy of function SVOPAIR, where all comment ° s''' ° '''have been removed and the prefix "≈_" --which is used to reduce the ° ''' '''chance of name conflicts-- has also been removed.)''' 'do' ° '0 0 1 2 3 4 showfn ''svopair''' ° '''Just as in SVOFFER, the function is ambivalent. If the left argumen ° t''' ° '''(PID) is missing, the branch to DYADIC on line [2] fails, and lines ° ''' ° '''[3-4] are evaluated. Line [1] converts the right argument to an''' ° '''array with at least one row and one column. Line [3] returns the''' ° '''degree of coupling of the right arguments.''' 'do' ° '0 5 6 7 8 9 showfn ''svopair''' ° '''The objective of lines [6-8] is to identify the row of SV that''' ° '''contains the name of the control variable. Line [6] shifts the''' ° '''rows of SV to the right so that there are no trailing blanks.''' ° '''Line [7] shifts the first letter of the last word on each line''' ° '''to the first row. (The function allows for the presence of''' ° '''"surrogates" in front of the shared variable names.) Line [8] final ° ly''' '''identifies the row containing a "C" in the first column.''' ° 'do' ° '''A first invocation of ÉSVO on the array SV should return the vector ° ''' ° '''1 1 on line [9]. If it does not, a branch to END (line [14]) ends'' ° ' '''the function.''' '0 10 11 12 13 showfn ''svopair''' ° '''Line [10] starts the EVENT clock. Line [12] tests for a change in'' ° ' ° '''the value of vector CV. A change causes exit to line [14]. Line [15 ° ]''' '''loops to line [11] until the event clock runs out.''' 'do' ° '0 14 15 showfn ''svopair''' ° '''Lines [14-15] end by seting the control shared variable.'',r' ° X '''NOW BACK TO THE SCOPE OF AP 210''' 'end' ° *(1996 4 14 12 10 16 288) ° FTEACH3 ÉFX 'TEACH3' 'Σ Control variable' '''THE CONTROL VARIABLE'',r' ° '''Now that both variables are active we can proceed with issuing''' ° '''commands to process DOS files. When dealing with files, we must''' ° '''recognize that there are three types of information that are needed ° :'',r' ° ''' A. The name (including the path name) of the file to be process ° ed''' ° ''' B. The type of operation to be performed (read, write, delete)' ° '' ''' C. The specific record to be processed''' 'do' ° '''In addition, in general, there are different types of files. For''' ° '''example, there are files that'',r' ° ''' a. can be read only, or can be read and writen into''' ° ''' b. fixed length files, or variable length files''' ° ''' c. direct access files or sequential files''' ° ''' d. ASCII files, Character files, boolean, and APL2 data files'', ° r' ° '''To handle this great diversity, the AP210 control variable operates ° ''' '''in two modes: COMMAND mode, and SUBCOMMAND mode.''' 'do' ° '''The command mode must be issued first. It specifies the general nat ° ure''' ° '''of the operation, the file name, and the type of data to be process ° ed.''' ° '''The subcommand mode specifies the type of file, whether the operati ° on''' ° '''is to be read or write, and the record number and possibly the''' ° X '''starting position of the read process.''' 'end' ° *(1996 4 14 12 10 27 332) ° FTEACH4 ÉFX 'TEACH4' 'Σ Command mode of control variable' ° '''COMMAND MODE'',r' ° '''In the command mode, the right argument is a character string.''' ° '''It has the following format:'',r' ° ''' command,filespec[,code]'',r' 'do' ° '''The command is a two letter abbreviation giving the type of action' ° '' '''that is to be performed:'',r' ° ''' IR open file for reading only''' ° ''' IW open file for read or/and write''' ° ''' DL delete file''' ''' RN rename file'',r' 'do' ° '''The command is followed by a comma, and then by a file specificatio ° n'',r' ° '''A third argument, the file code, is optional. It specifies the natu ° re''' ° '''of the data type. Four data types are supported by AP210:'',r' ° ''' A APL2 objects (This is the default)''' ° ''' B Bit strings packed 8 bits per byte without headers''' ° ''' C Character strings in APL2 internal (ASCII) code''' ° ''' D ASCII strings of characters'',r' ° '''Codes B and C require the file records to be of fixed length. Code' ° '' '''D may be used with variable record lengths, as can code A.''' ° 'do' ° '''There is one more code, T for "Translate". This indicates that the' ° '' ° '''record is a string of characters, without any header, to be transla ° Xted''' '''according to the AP 210 translate table.''' 'end' ° *(1996 4 14 12 10 44 400) ° FTEACH5 ÉFX 'TEACH5;T' 'Σ Subcommand mode' ° 'T╜210 SVOPAIR ''C210'' ''D210''' ° '''As an example, let us assume we wish to store some APL2 arrays in'' ° ' ° '''a file. The file is to be called "TEST210", and is to be placed in' ° '' '''the current directory (which is the default).'',r' ° 'show ''C210╜''''IW,TEST210''''''' ° '''Note that we did not use the file code, since APL2 type file is the ° ''' '''default.''' 'do' ° '''At this point we do not know whether our command was succesfully''' ° '''completed. However, since variable C210 has been assigned a value'' ° ' '''(the character string IW,TEST210), it can be referenced.''' ° '''It''''s contents is not the character string, but a numeric integer ° ''' ° '''value that identifies the "completion code". We can find out what'' ° ' '''this code is, merely by referencing C210'',r' 'show ''C210''' ° '''A code of 0 means that the control command has successfully opened' ° '' '''file TEST210.'',r' ° '''We may at this point wish to determine if a file by that name alrea ° dy''' ° '''exists. To do that, we merely would read a record from the file. We ° ''' ° '''could also just write a new record into the file. In either case, w ° Xe''' '''must issue a CONTROL SUBCOMMAND.''' 'end' ° *(1996 4 14 12 11 10 268) ° FTEACH6 ÉFX 'TEACH6' 'Σ Control subcommands' ° '''CONTROL SUBCOMMANDS'',r' ° '''Whenever the Control Command is IR or IW, it must be followed by on ° e''' '''or more subcommands. These are of the form'',r' ° ''' C210╜operation [,record number [,scan distance]]'',r' ° ''' or using IBM abbreviations: C210╜op[,rn[,rs]]'',r' ° '''Unlike the control command, this assignment is numeric, and the val ° ues''' ° '''are positive integers. Here is a listing of available "operation"'' ° ' '''codes:'',r' ''' OP MEANING DEFAULTS''' ° ''' 0 Read fixed length record rn╜0 rs╜128 sequential read''' ° ''' 1 Write fixed length record rn╜0 rs╜128 sequential write'' ° ' ''' 2 Read direct record rn╜starting byte rs╜128''' ° ''' 3 Write direct record rn╜starting byte rs╜128''' ° ''' 4 Read variable length record (Depends on codes A or D)''' ° ''' 5 Write variable length record " " " "'',r' ° 'do' ° '''Let us assume that we have two APL2 variables we wish to store''' ° '''in file TEST210:'',r' ° 'show ''ONE╜''''CHARACTER STRING'''''' ''TWO╜∞20''' ° '''Each step requires the following sequence:'',r' ° 'show ''D210╜ONE'' ''C210╜5'' ''C210'' ''D210╜TWO'' ''C210╜5'' ''C210' ° X'' 'end' ° *(1996 4 14 12 11 22 316) ° FTEACH7 ÉFX 'TEACH7' 'Σ Control subcommand continued' ° '''Notice that each assignment to D210 must be followed by two control ° ''' ° '''subcommands, one to specify the nature of the operation, and one to ° ''' '''test the Return Code.''' 'do' ° '''At this point we can continue by verifying whether the information' ° '' ° '''been stored properly. Note that record numbers are in 0 index origi ° n.'',r' ° 'show ''C210╜4 0'' ''C210'' ''D210'' ''C210╜4 1'' ''C210'' ''D210''' ° '''When reading a file, each reference to D210 must be preceeded by tw ° o''' ° '''control commands; one to specify the nature of the read operation, ° and''' '''one to test the Return Code.'',r' ° '''When a file is no longer to be used, it has to be closed. This is'' ° ' ° '''done simply by assigning a null string to the control variable'',r' ° 'show ''C210╜''''''''''' ° '''Once a a file has been closed, it is permissible to issue another'' ° ' '''Control Command'',r' ° 'show ''C210╜''''IR,C:\APL2\testXXX'''''' ''C210''' ° '''The Return Code 2 means that the named file does not exist. Had the ° ''' ° '''Control Command started with IW, instead with IR, a new file named' ° X'' '''''''testXXX'''' would have been defined.''' 'end' ° *(1996 4 14 11 55 55 620) ° FTEACH8 ÉFX 'TEACH8' 'Σ Return Codes' '''RETURN CODES'',r' ° '''You are encouraged to practice different combinations of Control''' ° '''Commands and Subcommands. As you do, you will invariably get any on ° e''' ° '''of several non-zero Return Codes. You can find the meanings of thes ° e''' '''on page 216 of your APL2 USER''''S GUIDE.'',r' ° '''Once you become familiar with the usage of AP210, you may wish to'' ° ' ° '''define your own functions to read and write specific file applicati ° ons.''' 'do' ° '''IBM supplies two workspaces named APLFILE and FILE. These invoke th ° e''' ° '''AP210 and support functions to OPEN, CLOSE, READ and WRITE records. ° ''' ° '''It is entirely possible that these workspaces will satisfy many of' ° '' ° '''your requirements. In any case, you can use these workspaces (or''' ° '''functions within) as a basis for your own applications.'',r' ° '''Before we leave AP210, we should delete file TEST210. This can be'' ° ' '''done with Control Command'',r' ° 'show ''C210╜''''DL,TEST210'''''' ''C210''' ° '''and let us not forget to release the Shared Variable'',r' ° X 'show ''ÉSVR■ ''''C210'''' ''''D210''''''' 'TEACH8A' ° *(1996 4 14 12 11 53 440) ° FTEACH8A ÉFX 'TEACH8A;D;CMD' 'Σ Read the ASCII file APL2.CMD' ° '''You do not need to define your APL2 functions to access non-APL''' ° '''external files. IBM supplies workspace FILE in library 2, that''' ° '''contains just about any functionality that you are likely to need.' ° '' '''The workspace 2 FILES contains four groups of functions:'',r' ° ''' AP 210 group''' ''' AP 211 group''' ''' Delta group''' ° ''' Transfer group''' 'do' ° '''The AP 210 group contains functions that allow you to open, close a ° ''' ° '''file, to read or write bytes or records, find file size, to compare ° ''' ° '''two files, to display the contents of a file, to delete a file, and ° ''' '''to rename a file.'',r' ° '''The AP 211 group deals with functions useful with AP 211, which wil ° l''' '''be discussed later.'',r' ° '''Right now it is the "Delta Group" that is of interest''' 'do' ° '''This group contains only two functions: ╢FM and ╢FV. Both functions ° ''' ° '''are ambivalent. If the left argument is absent, these functions wil ° l''' ° '''read the contents of a file (specified in the right argument). If t ° he''' ° '''left argument is present, it must be a rank 2 character array. This ° ''' ° '''array will be written to the file specified in the right argument.' ° '' 'do' ° '''As an example, consider loading into this workspace the APL2.CMD fi ° le''' ° '''listed on page 11 of the User''''s Guide. Your APL2OS2 may not resi ° de''' ° '''on drive C. Therefore, before proceeding with this exercise, you mu ° st''' '''specify this drive:'',r' ° 'D╜╞(1 get '' ATTENTION! Enter the APL2OS2 drive (default is C:)'') ° ,''C''' ° '''On the assumption that this file has the following address:'',r' ° 'D,'':\APL2OS2\BIN\APL2.CMD'',r' ° '''its contents can be read into variable CMD'',r' ° 'show ''CMD╜╢FM D,'''':\APL2OS2\BIN\APL2.CMD'''''' ''µCMD'' ''DISPLAY ° CMD''' ° '''Function ╢FM retrieved this file as a rank 2 character array.''' ° '''Function ╢FV will retrieve the same data as a nested vector of''' ° '''individual records from that file'',r' ° 'show ''CMD╜╢FV D,'''':\APL2OS2\BIN\APL2.CMD'''''' ''µ■CMD'' ''DISPLAY ° 2╞CMD''' 'do' ° '''NOTE: If you merely desire to edit an ASCII text file, you may do s ° o''' '''using the ")HOST" command. Enter'',r' ° ''' )HOST apledit filename'',r' ° '''(replace the word "filename" by the address of the file to be edite ° Xd)''' 'end' ° *(1996 4 14 12 12 13 284) ° FTEACH9 ÉFX 'TEACH9;D211' 'Σ Auxilliary processor 211' ° '''AUXILLIARY PROCESSOR 211'',r' ° '''There are several features of AP210 that are inconvenient for certa ° in''' ° '''APL2 applications. For one, it may be necessary to know the content ° s''' ° '''of a file by record numbers. In APL, we are used to accessing data ° by''' ° '''name. With AP210, one has to know the file characteristics, while'' ° ' ° '''in APL we are used to let the system do such book-keeping. For thos ° e''' ° '''of us who prefer to deal with files as if these were merely extensi ° ons''' '''of APL, there is AP211.''' 'do' ° '''Auxilliary Processor 211 supports ONLY one Shared Variable.'',r' ° 'show ''211 SVOFFER ''''D211''''''' 'D211╜''DROP'' ''FUNCTION''' ° '''We can create a file, say FUNCTION with the following command'',r' ° 'show ''D211╜''''CREATE'''' ''''FUNCTION'''''' ''D211''' ° '''Referencing D211 after making an assignment to it is ALWAYS a good' ° '' ° '''idea. The Return Codes can be found on p 220 of the USER''''S MANUA ° L.''' 'do' ° '''If you were to repeat this command, the return code would be a ²17' ° '' ° '''indicating that the file is already in use. The file created by''' ° '''CREATE will have fixed lenth records of 1024 bytes. (This can be''' ° '''changed by inserting an alternate value as a third element of the'' ° ' '''CREATE assignment.)'',r' ° X ''' D211╜''''CREATE'''' filename record-size'',r' 'end' ° XNTHREE 2 3 3 1 2 3 4 5 6 7 8 9 ° XATWO╜1-ÉIO-∞20 ° XCa 0 % ° *(1991 11 11 8 26 35 408) ° Faddquote ÉFX 'u╜addquote w' ° 'Σ Put quotes around a string, and double existing quotes' ° X 'u╜ÉAV[40],((1+w=ÉAV[40])/w),ÉAV[40]' ° *(1992 5 6 8 49 44 496) ° Fans ÉFX 'U╜V ans W;A;R;T' 'Σ Respond to an inquiry' ° 'T╜(0=ÉNC ''V'')doif ''V╜'''' ''''''' '╕(0⌠1╞0╞εV)/L0' ''' '',W' ° 'U╜É' '╕(0╧V)/0' 'U╜VµU' '╕0' 'L0:T╜(1<╧V)doif ''R╜1╟V'' ''V╜╞V''' ° 'æ╜A╜'' '',W,V' 'U╜(µA)╟æ' '╕(~T)/0' ° X '╕((0=╞0╞R)doif ''U╜RµU,'''' '''''')/0' 'U╜π(U⌠R)ΓU' ° *(1991 11 11 8 26 35 408) ° XFaq ÉFX 'u╜aq w' 'Σ Enclose quoted string' 'u╜Γaddquote w' ° *(1991 11 11 8 26 35 408) ° Fav ÉFX 'av;a;n;i;ÉIO' 'Σ Display characters in the Atomic vector' ° 'ÉIO╜0' 'a╜22 78µ'' ''' 'n╜3 0«φ12 22µ1+∞256' ° 'a[;,(6⌡∞12)°.+2 3 4]╜n' 'a[;6+6⌡∞12]╜φ12 22µÉAV' ° X 'a[7 8 10 13;6]╜'' ''' 'a[14+∞8;68 69 70 72]╜'' ''' 'a' ° *(1996 4 7 14 15 40 384) ° Fcopyright ÉFX 'copyright' 'Σ Copyright statement' ° '(10µ'' ''),''Copyright, Z. V. Jizba, 1995'',r' ° '''To see disclaimers, enter ÉCR ''''copyright''''''' 'do' '╕0' ° '''This and subsequent workspaces labelled TEACHxx are made available' ° '' ° '''at no cost to anyone who desires to learn how to use effectively''' ° '''the IBM/OS2 version of APL2.'',r' ° '''This software is provided "AS IS" with no WARRANTY of any kind, eit ° her''' ° '''express or implied. Any risk in its use resides with you, the user ° Xof''' '''these tutorials.''' '''(PRESS ENTER to continue)''' ° XCd 0 " ° *(1991 11 11 8 26 37 416) ° Fdate ÉFX 'u╜date w' 'Σ Format date and time of day' 'u╜«6╞w' ° X 'u╜('' ''⌠u)Γu' 'u╜εu,■''-- .. ''' ° XCdig 1 10 1234567890 ° *(1991 11 11 8 26 34 404) ° Fdo ÉFX 'do;t;e;b' 'Σ Expression driver' 'e╜''''' 'æ╜'' ''' 't╜æ' ° '╕(^/'' ''=t)/0' ° '╕(('':''εt)doif ''b╜evaldd (+/^\'''' ''''=t)╟t'')/2' ° '''e╜ÉEM'' ÉEA t' '╕(0=µ,e)/2' ° '''This is not a valid APL2 expression''' 'æ╜''*''' '╕(''?''⌠╞1╟æ)/2' ° X 'e' '╕2' ° *(1991 11 11 8 26 34 404) ° Fdoif ÉFX 'U╢╜V╢ doif W╢;t╢' 'Σ Rule' '╕(^/~U╢╜V╢)/0' ° X '''U╢╜V╢ doif■ W╢'' ÉEA ''»V╢/W╢''' ° XNdos 0 ²26 ° XCe 1 0 ° *(1996 3 31 14 34 39 548) ° Fend ÉFX 'end' '''²²''' 'e╜''''' 'æ╜'' ''' 't╜æ' '╕(^/'' ''=t)/0' ° '╕(('':''εt)doif ''b╜evaldd (+/^\'''' ''''=t)╟t'')/3' ° '''e╜ÉEM'' ÉEA t' '╕(0=µ,e)/0' ° '''This is not a valid APL2 expression''' 'æ╜''*''' '╕(''?''⌠╞1╟æ)/0' ° X 'e' ° *(1991 11 11 8 26 35 408) ° XFendd ÉFX 'endd' 'Σ End of document' '20µ''²''' 'do' ° *(1995 10 8 13 54 41 564) ° Ferase ÉFX 'erase;t;DISPLAY;OS2;GO;PROFILE;SVOFFER;SVOPAIR;╢FM;╢FV' ° 't╜ÉNL 3' 't╜(~t^.εlc,'' '')≡t' 't╜ÉEX(~t[;∞5]^.=''TEACH'')≡t' ° X 't╜ÉNL 2' 't╜ÉEX(~t^.εlc,'' '')≡t' 't╜ÉNL 4' 't╜ÉEX(~t^.εlc,'' '')≡t' ° *(1991 11 11 8 26 36 412) ° Fevaldd ÉFX 'u╜evaldd w;c;n' ° 'Σ Evaluate a direct definition expression' 'u╜0' 'n╜(w∞''Σ'')-1' ° 'c╜(((n╞w)⌠'':'')Γn╞w),Γ''ΣDD '',(n+1)╟w' '╕(label╞c)/0' ° '╕((2=µc)doif ''u╜showdd 1╙c'')/0' ° '╕((3=ÉNC╞c)doif ''u╜⌡µÉ╜(╞c),'''' is already defined.'''''')/0' ° '╕((3=µc)doif ''u╜simdd c'')/0' 'c╜(Γ''α∙ aw'')replace■c' ° 'u╜ε''u╜'',((''a''εεc[2 3 4])/''a ''),(╞c),'' w;t;b''' ° 'u╜u(5πc)(''b╜(t╜'',(3πc),'')/'',addquote ''u╜'',4πc)' ° X 'u╜u,''╕(t doif b)/0''(''u╜'',2πc)' 'u╜╧ÉFX u' ° *(1991 11 11 8 26 36 412) ° Fexit ÉFX 'exit w' 'Σ Exit if there are too many suspended functions' ° X '╕((10>µÉLC)doif ''w'')/0' '''Please re-enter '',w' '╕' ° XCf 1 2 { ° XCg 1 2 } ° *(1996 4 18 14 22 21 380) ° Fget ÉFX 'u╜v get w;t' 'Σ Prompt for response from keyboard' ° 't╜(0=ÉNC ''v'')doif ''v╜1''' 'w╜w,(~²1╞v)/'': ''' 'L0:æ╜w' 't╜æ' ° '╕((''╕''=(µw)╟t)doif ''╕'')/0' '╕(^/'' ''=w)/L1' ° 'Σ ╕((~w╧(µw)╞t)doif ''''''PLEASE DO NOT BACKSPACE'''''')/L0' ° 't╜(µw)╟t' 'L1:u╜(²1+(,'' ''⌠t)∞1)╟t' '╕(1╞v)/0' 't╜(u⌠'' '')Γu' ° X 'u╜(µt),(Γu),t' ° *(1991 11 11 8 26 36 412) ° Fglobals ÉFX 'globals' 'Σ Initialize useful global variables' 'r╜2╙ÉTC' ° 'q╜40╙ÉAV' 's╜Φp╜'' '',d╜35╙ÉAV' 'uc╜''ABCDEFGHIJKLMNOPQRSTUVWXYZ''' ° 'lc╜''abcdefghijklmnopqrstuvwxyz''' 'dig╜''1234567890''' ° X 'g╜'' '',h╜126╙ÉAV' 'f╜ÉAV[33 124]' 'a╜38╙ÉAV' ° XCh 0 } ° *(1996 4 9 13 38 53 532) ° Fhelp ÉFX 'help' ° '''If you feel that a single linear reading of these lessons is not th ° e''' ° '''best way to learn about APL2OS2, you may try to do the following.'' ° ,r' '''1. At any pause enter: ÉCR ''''TEACH''''''' ° ''' (a listing of the components of the tutorial workspace will appe ° ar)''' ° '''2. Jot down the names that appear in UPPER CASE --mostly TEACHxx--' ° '' ° '''3. Each of these is a component of the lesson that can be invoked'' ° ' ° ''' at the pause simply by entering its name. This will repeat that' ° '' ° ''' portion of the tutorial. The completion of each portion is marke ° Xd''' ''' by a line containing ²².''' 'end' ° *(1991 11 11 8 26 36 412) ° Finitialize ÉFX 'initialize;t' 'Σ Initialize workspace' 'erase' ° X 'globals' ° *(1991 11 11 8 26 35 408) ° Fkeys ÉFX 'keys' 'Σ Display keyboard' ° ''' 1 2 3 4 5 6 7 8 9 0 + ⌡''' ° '''SHFT ╒ ■ ² < ≤ = ≥ > ⌠ δ ^ - ÷''' ° '''ALT ╘ ƒ · ⁿ √ Φ φ Θ ╡ τ σ ! Æ''' '''''' ° ''' Q W E R T Y U I O P ╜ ╙ ╧''' ° '''SHFT ? ∙ ε µ ~ ╞ ╟ ∞ Ω * ╕ ╨ ╤''' ° '''ALT q w e r t y u i o p æ ≈ ╥''' ° '''CTRL ┌ ┬ ┐ ╔ ╦ ╗''' '''''' ° ''' A S D F G H J K L [ ]''' ° '''SHFT α ⌐ ╛ _ ╖ ╢ ° '''' É ( )''' ° '''ALT a s d f g h j k l » «''' ° '''CTRL ├ ┼ ┤ ─ ═ ╠ ╬ ╣''' '''''' ° ''' Z X C V B N M , . /''' ° '''SHFT Γ π ∩ ¼ ¥ ÿ | ; : \''' ° '''ALT z x c v b n m Σ ± ≡''' ° '''CTRL └ ┴ ┘ │ ║ ╚ ╩ ╝''' '''''' ° X '''Toggle switch to ASCII is CTL-BACKSPACE''' '''CTRL+G gives beep''' ° *(1991 11 11 8 26 36 412) ° Flabel ÉFX 'u╜label w' ° 'Σ Return 1 if w is not a valid character string label (also excludes ° Xl.c.)' '╕(u╜(1<µµw)δ1<╧w)/0' '╕(u╜~^/wεlc,uc,dig)/0' 'u╜w[1]εlc,dig' ° XClc 1 26 abcdefghijklmnopqrstuvwxyz ° *(1991 11 11 8 26 36 412) ° Fnon ÉFX 'non;t;rc;et;r' ° 'Σ Ignore invalid keyboard entries, but evaluate valid APL2 expression ° s' 'æ╜'' ''' 't╜æ' '╕(0=µ(t⌠'' '')/t)/0' '(rc et r)╜ÉEC t' ° X '╕(0=rc)/2' '╕((1=rc)doif ''r'')/2' '╕2' ° *(1991 11 11 8 26 36 412) ° Fnotb ÉFX 'u╜notb w' 'Σ Remove trailing blanks' ° '╕((1<╧w)doif ''u╜notb■ w'')/0' '╕((1<µµw)doif ''u╜πnotb Γ[2]w'')/0' ° X 'u╜(1-(,'' ''⌠Φw)∞1)╟w' ° XCp 1 2 " ° *(1991 11 11 8 26 36 412) ° Fpause ÉFX 'v pause w;t' ° 'Σ Pause, then print w v spaces right and return' ° X 't╜(0=ÉNC ''v'')doif ''v╜6''' 'do' '(vµ'' ''),w' 'do' ° XCq 0 ' ° XCr 0 ° *(1991 11 11 8 26 36 412) ° Freplace ÉFX 'u╜v replace w;i;r;s' 'Σ Replace elements in v in w' ° 'i╜Γ∞µu╜w' 's╜2πv╜(v⌠'' '')Γv' 'i╜⌡r╜i⌡■Γ[1]w°.=╞v' ° X 'u[(εi)/εr]╜s[(εi)/εi⌡■∞µs]' ° *(1991 11 11 8 26 37 416) ° Fround ÉFX 'u╜v round w' 'Σ Half adjust w to vth decimal' ° X 'u╜(╛0.5+w⌡10*v)÷10*v' ° XCs 1 2 " ° *(1991 11 11 8 26 37 416) ° Fshow ÉFX '╢v show ╢w;╢t;╢b' 'Σ Display and execute ╢w' ° '╢t╜(0=ÉNC ''╢v'')doif ''╢v╜0''' ° '╕((0=╧╢w)doif ''show ╢w,'''' '''''')/0' ° '╕((1<╧╢w)doif ''╢v show■ ╢w'')/0' ''' '',╢w' ° X '╕((╢v^'':''ε╢w)doif ''╢t╜evaldd ╢w'')/L0' '''ÉEM'' ÉEA ╢w' 'L0:do' ° *(1991 11 11 8 26 37 416) ° Fshowdd ÉFX 'u╜showdd w;a;b;c;r' ° 'Σ Display a direct definition function' ° '╕((1=╧w)doif ''u╜showdd Γw'')/u╜0' ° '╕((3⌠ÉNC╞w)doif ''(ε╞w),'''' is not a function'''''')/0' ° 'c╜Γ[2]ÉCR╞w' 'c╜notb(2╞c),(Γ''aw α∙'')replace■2╟c' ° '╕((~''ΣDD''╧3╞2πc)doif ''''''Not a direct definition function'''''')/ ° 0' 'u╜1' 'b╜('' ''⌠╞c)Γ╞c' 'a╜'' ''' 'r╜2╟3πc' ° '╕((3=µc)doif ''a,(╞w),'''':'''',r,(3<µ2πc)/'''' Σ'''',3╟2πc'')/0' ° 'a╜a,(╞w),'':'',(2╟5πc),'':''' 'b╜(+\r=''('')-+\r='')''' 'b╜b∞0' ° X 'a╜a,(²3╟(b-1)╞3╟r),'':'',2╟»(b+2)╟r' 'a,(3<µ2πc)/'' Σ'',3╟2πc' ° *(1991 11 11 8 26 37 416) ° Fshowfn ÉFX 'u╜v showfn w;f;n;t;ÉIO' 'Σ Simulate the STSC ÉVR command' ° 't╜(0=ÉNC ''v'')doif ''v╜0''' 'ÉIO╜0' ° 'u╜r,'' '',''╖'',w,''[É]'',(╞v)╞''╖''' 'n╜1╞µf╜ÉCR w' 'n╜«∞n' ° 'n╜(n⌠'' '')Γn' 'f╜(π''['',■n,■Γ''] ''),f' ° 't╜(1<µ,v)doif ''f╜f[1╟v;]'' ''u╜''''''''''' 'u╜²1╟u,r,,f,r' ° X 'u╜((-+/^\'' ''=Φu)╟u),('' ''(r,'' ╖'',date 2 ÉAT w))[╞v],r' ° *(1991 11 11 8 26 37 416) ° Fsimdd ÉFX 'u╜simdd w;e' 'Σ Simple direct definition mode' 'u╜0' ° '╕((0⌠ÉNC╞w)doif ''''''Already defined'''''')/0' 'e╜''α''ε2πw' ° 'w[2]╜Γ''u╜'',''α∙ aw'' replace 2πw' 'w╜w[1 3 2]' ° X 'w[1]╜Γε''u╜'',(e/''a ''),w[1],'' w''' 'u╜╧ÉFX w' ° *(1995 10 2 13 45 46 524) ° Fsvopair ÉFX 'DC╜PID svopair SV;CV' 'SV╜(²2╞1 1,µSV)µSV╜πSV' ° '╕(2=ÉNC ''PID'')/DYADIC' 'DC╜ÉSVO SV' '╕0' 'DYADIC:' ° 'CV╜(-+/^\ΦSV='' '')ΦSV' 'CV╜(-+/^\ΦCV⌠'' '')ΦCV' 'CV╜CV[;ÉIO]=''C''' ° '╕(1^.⌠CV/DC╜PID ÉSVO SV)/END' 'ÉSVE╜15' 'CHECK:' ° '╕(1^.⌠CV/DC╜ÉSVO SV)/END' '╕(0⌠ÉSVE)/CHECK' 'END:' ° X 'CV╜1 0 1 0 ÉSVC CV≡SV' ° XCt 1 7 ° XCuc 1 26 ABCDEFGHIJKLMNOPQRSTUVWXYZ ° *(1995 10 8 14 0 19 264) ° F╢FM ÉFX 'R╜A ╢FM B;E;F;G;H;I;J;TC;ÉIO;C╢F;D╢F' ° 'Σ Emulation of APL2/370 ╢FM built-in function using AP210' ° 'Σ Licensed Materials - Property of IBM' 'ÉIO╜0' ° '(G H)╜210 ÉSVO■''C╢F'' ''D╢F''' 'ÉSVE╜15' 'SVCHECK:' ° '(G H)╜ÉSVO■''C╢F'' ''D╢F''' '╕((G=2)^(H>0))/SVOK' ° '╕(0⌠ÉSVE)/SVCHECK' '╕LB' 'SVOK:' 'G╜1 0 1 0 ÉSVC ''C╢F''' 'G╜0' ° 'H╜32768' '╕(0=ÉNC ''A'')/LA' 'C╢F╜''DL,'',B' '╕(^/0 2⌠╞E╜C╢F)/LC' ° '╕((δ/1 2=µµA)^0=⌡/µA)/LC' 'C╢F╜''IW,'',B,'',D''' '╕(0⌠╞E╜C╢F)/LC' ° 'D╢F╜''A''' 'C╢F╜5' '╕(0⌠╞E╜C╢F)/LC' 'C╢F╜4 0' '╕(0⌠╞E╜C╢F)/LC' ° 'TC╜1╟D╢F' '╕((3≤µE),(2=╧A)^1=µE╜µA)/LJ,LI' 'I╜A,╞TC' ° '»(2=µTC)/''I╜I,╞1╟TC''' 'I╜,I' '╕LO,B╜A╜''''' 'LI:B╜∞µF╜2+╞■µ■A' ° 'LN:E╜1⌐+/H≥+\F' 'I╜εA[E╞B],■ΓTC' 'B╜E╟B' 'F╜E╟F' 'LO:D╢F╜(J╜H╛µI)╞I' ° 'C╢F╜3,G,J' '╕((8=╞E),0⌠╞E╜C╢F)/LG,LC' 'G╜G+J' '╕(H≥µI)/LF' ° '╕LO,µI╜H╟I' 'LF:╕(0⌠µB)/LN' '╕0,R╜C╢F,C╢F╜∞0' ° 'LA:C╢F╜''IR,'',B,'',D''' '╕(0⌠╞E╜C╢F)/LC' '╕(0⌠B╜D╢F)/LMO' ° '╕0,0µR╜0 0µ''''' 'LMO:R╜''''' 'J╜ÉTC[2]' 'LE:C╢F╜2,G,H╛B' ° '╕((8=╞E),0⌠╞E╜C╢F)/LG,LC' 'F╜(+\0+ÉTC[2]=J)ΓJ╜J,D╢F' 'J╜╞²1╞F' ° 'R╜R,1╟■(-B>H)╟F' '╕(0≥B╜B-H)/LX' '╕LE,G╜G+H' ° 'LX:R╜(-(ÉAF 26)=╞╞²1╞R)╟R' 'R╜(-0=µ╞²1╞R)╟R' 'R╜(-ÉTC[1]=²1╞■R)╟■R' ° 'R╜πR' '╕0' 'LG:╕(H=128)/LC' '╕((LO,LE)[0=ÉNC ''A'']),H╜128⌐⌐H÷2' ° X 'LB:ÉES ''AP210 share offer failed''' 'LJ:ÉES 5 2' 'LC:╕0,R╜E' ° *(1994 4 21 21 0 0 240) ° F╢FV ÉFX 'R╜A ╢FV B;E;F;G;H;I;J;TC;ÉIO;C╢F;D╢F' ° 'Σ Emulation of APL2/370 ╢FV built-in function using AP210' 'Σ' ° 'Σ Licensed Materials - Property of IBM' ° 'Σ 5621-430, 5648-065, 5765-012 (c) Copyright IBM Corp. 1983, 1994.' ° 'Σ' 'Σ A is optional and if omitted the file will be read.' ° 'Σ A if included defines the CHARACTER data to be written.' ° 'Σ B has the syntax [/path/]filename' 'ÉIO╜0' ° '(G H)╜210 ÉSVO■''C╢F'' ''D╢F'' Σ Offer a pair of variables' ° 'ÉSVE╜15 Σ Wait up to 15 seconds for accep ° ts' 'SVCHECK:' ° '(G H)╜ÉSVO■''C╢F'' ''D╢F'' Σ Check degree of coupling' ° '╕((G=2)^(H>0))/SVOK Σ Out of loop if shared' ° '╕(0⌠ÉSVE)/SVCHECK Σ Retry if time left' ° '╕LB Σ Out of time, quit' 'SVOK:' ° 'G╜1 0 1 0 ÉSVC ''C╢F'' Σ Set access control' ° 'G╜0 Σ Initialise file pointer' ° 'H╜32768 Σ Record size (may be reduced)' ° '╕(0=ÉNC ''A'')/LA' ° 'C╢F╜''DL,'',B Σ Delete existing file if any' ° '╕(^/0 2⌠╞E╜C╢F)/LC' ° '╕((δ/1 2=µµA)^0=⌡/µA)/LC Σ Check for something to write' ° 'C╢F╜''IW,'',B,'',D'' Σ Open new file' '╕(0⌠╞E╜C╢F)/LC' ° 'D╢F╜''A'' Σ Write a single variable record' 'C╢F╜5' ° '╕(0⌠╞E╜C╢F)/LC' 'C╢F╜4 0 Σ Read it back' ° '╕(0⌠╞E╜C╢F)/LC' ° 'TC╜1╟D╢F Σ Capture the line terminators (CR/LF or LF) ° ' '╕((3≤µE),(2=╧A)^1=µE╜µA)/LJ,LI' ° 'E╜'' ''=,²1╞[1]A╜(²2╞1 1,µA)µA Σ Check for any trailing blanks to rem ° ove' 'I╜A,╞TC Σ Append line terminator to each row' ° '»(2=µTC)/''I╜I,╞1╟TC'' Σ Append another if there are two' ° 'I╜,I Σ Make into a simple vector' '╕(~δ/E)/LH' ° 'I╜(,(~E±Φ^\'' ''=ΦA[E/∞╞µA;]),((╞µA),µTC)µ1)/I Σ Remove trailing blan ° ks' 'LH:╕LO,B╜A╜''''' ° 'LI:╕(~δ/E╜'' ''=ε²1╞■A)/LD Σ Check for any trailing blanks to remove ° ' 'E╜E/∞µE Σ Convert to indices' ° 'LL:A[╞E]╜Γ(-('' ''=ΦF)∞0)╟F╜,(╞E)πA Σ Remove trailing blanks' ° '╕(0⌠µE╜1╟E)/LL' 'LD:B╜∞µF╜2+╞■µ■A' ° 'LN:E╜1⌐+/H≥+\F Σ Number of items that will fit in record (minimum ° of 1)' ° 'I╜εA[E╞B],■ΓTC Σ Append line terminators to each item' ° 'B╜E╟B' 'F╜E╟F' 'LO:D╢F╜(J╜H╛µI)╞I' 'C╢F╜3,G,J' ° '╕((8=╞E),0⌠╞E╜C╢F)/LG,LC' ° 'G╜G+J Σ Increment file pointer' ° '╕(H≥µI)/LF Σ Check if all of this data has been written ° ' '╕LO,µI╜H╟I' 'LF:╕(0⌠µB)/LN' ° '╕0,R╜C╢F,C╢F╜∞0 Σ Close the file and exit' ° 'LA:C╢F╜''IR,'',B,'',D'' Σ Open file for read' '╕(0⌠╞E╜C╢F)/LC' ° '╕(0⌠B╜D╢F)/LMO Σ Is file empty?' ° '╕0,R╜0µΓ'''' Σ File empty return an empty vector' ° 'LMO:R╜''''' 'J╜ÉTC[2]' 'LE:C╢F╜2,G,H╛B' '╕((8=╞E),0⌠╞E╜C╢F)/LG,LC' ° 'F╜(+\0+ÉTC[2]=J)ΓJ╜J,D╢F Σ Split each record into component vectors' ° 'J╜╞²1╞F Σ Store last (incomplete) item' ° 'R╜R,1╟■(-B>H)╟F' '╕(0≥B╜B-H)/LX' ° '╕LE,G╜G+H Σ Increment file pointer' ° 'LX:R╜(-(ÉAF 26)=╞╞²1╞R)╟R Σ Remove EOF record (if there)' ° 'R╜(-0=µ╞²1╞R)╟R Σ Remove last empty record' ° 'R╜(-ÉTC[1]=²1╞■R)╟■R Σ Remove CR''s if present' ° '╕(~δ/E╜'' ''=ε²1╞■R)/0 Σ Check for any trailing blanks to remove' ° 'E╜E/∞µE Σ Convert to indices' ° 'LM:R[╞E]╜Γ(-('' ''=ΦF)∞0)╟F╜,(╞E)πR Σ Remove trailing blanks' ° '╕(0⌠µE╜1╟E)/LM' '╕0' 'LG:╕(H=128)/LC' ° '╕((LO,LE)[0=ÉNC ''A'']),H╜128⌐⌐H÷2 Σ Halve record length' ° 'LB:ÉES ''AP210 share offer failed''' ° X 'LJ:ÉES 5 2 Σ Rank error' 'LC:╕0,R╜E' °