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Contents Chapter 1: Primitive Functions 1 Scalar Functions 1 Mixed Functions 4 Conformability 7 Fill Elements 7 Axis Operator 8 Functions (A-Z) 8 Abort: 9 Add: 10 And, Lowest Common Multiple: 11 Assignment: 12 Assignment (Indexed): 15 Assignment (Selective): 20 Binomial: 22 Branch: 23 Catenate/Laminate: 25 Catenate First: 27 Ceiling: 27 Circular: 28 Conjugate: 29 Deal: 29 Decode: 30 Depth: 32 Direction (Signum): 33 Disclose: 34 Divide: 35 Drop: 36 Drop with Axes: 37 Enclose: 38 Enclose with Axes: 39 Encode: 40 Enlist: 42 Equal: 43 Excluding: 44 Execute (Monadic): 45 Execute (Dyadic): 45 Expand: 46 Expand First: 47 iv Exponential: 47 Factorial: 47 Find: 48 First: 49 Floor: 49 Format (Monadic): 50 Format (Dyadic): 54 Grade Down (Monadic): 56 Grade Down (Dyadic): 57 Grade Up (Monadic): 59 Grade Up (Dyadic): 61 Greater: 62 Greater Or Equal: 63 Identity: 63 Index: 64 Index with Axes: 67 Index Generator: 68 Index Of: 69 Indexing: 70 Intersection: 74 Left: 75 Less: 76 Less Or Equal: 76 Logarithm: 77 Magnitude: 77 Match: 78 Matrix Divide: 79 Matrix Inverse: 81 Maximum: 82 Membership: 82 Minimum: 82 Minus: 82 Mix: 83 Multiply: 84 Nand: 84 Natural Logarithm: 84 Negative: 85 Nor: 85 Not: 85 Not Equal: 86 Not Match: 86 Or, Greatest Common Divisor: 87 Partition: 88 Partitioned Enclose: 90 Pi Times: 91 v Pick: 91 Plus: 92 Power: 92 Ravel: 93 Ravel with Axes: 93 Reciprocal: 96 Replicate: 96 Reshape: 98 Residue: 98 Reverse: 99 Reverse First: 99 Right: 99 Roll: 100 Rotate: 100 Rotate First: 101 Same: 102 Shape: 102 Split: 103 Subtract: 103 Table: 104 Take: 105 Take with Axes: 106 Times: 107 Transpose (Monadic): 107 Transpose (Dyadic): 107 Type: 108 Union: 109 Unique: 109 Without: 109 Zilde: 109 Chapter 2: Primitive Operators 111 Operator Syntax 111 Axis Specification 112 Operators (A-Z) 113 Assignment (Modified): 113 Assignment (Indexed Modified): 114 Assignment (Selective Modified): 115 Axis (with Monadic Operand): 115 Axis (with Dyadic Operand): 116 Commute: 119 Composition (Form I): 120 Composition (Form II): 121 Composition (Form III): 122 vi Composition (Form IV): 122 Each (with Monadic Operand): 123 Each (with Dyadic Operand): 124 Inner Product: 125 Outer Product: 126 Power Operator: 127 Reduce: 129 Reduce First: 132 Reduce N-Wise: 132 Scan: 133 Scan First: 134 Spawn: 135 Variant: 136 I-Beam: 139 Syntax Colouring: 140 Core to APLCore: (UNIX only) 141 Number of Threads: 142 Parallel Execution Threshold: 142 Memory Manager Statistics: 143 Update DataTable: 146 Read DataTable: 149 Export To Memory: 152 Component Checksum Validation: 152 Fork New Task: (UNIX only) 153 Change User: (UNIX only) 154 Reap Forked Tasks: (UNIX only) 155 Signal Counts: (UNIX only) 157 Thread Synchronisation Mechanism: 157 Random Number Generator: 158 Chapter 3: System Functions & Variables 159 System Variables 161 System Namespaces 162 System Constants 163 System Functions 164 Character Input/Output: 172 Evaluated Input/Output: 174 Underscored Alphabetic Characters: 176 Alphabetic Characters: 176 Account Information: 177 Account Name: 177 Arbitrary Output: 178 Attributes: 179 Atomic Vector: 183 vii Atomic Vector - Unicode: 183 Base Class: 186 Class: 187 Clear Workspace: 189 Execute Windows Command: 190 Start Windows Auxiliary Processor: 193 Canonical Representation: 194 Change Space: 196 Comparison Tolerance: 198 Copy Workspace: 199 Digits: 201 Decimal Comparison Tolerance: 201 Display Form: 202 Division Method: 205 Delay: 205 Diagnostic Message: 206 Extended Diagnostic Message: 207 Dequeue Events: 212 Data Representation (Monadic): 215 Data Representation (Dyadic): 216 Edit Object: 217 Event Message: 217 Exception: 218 Expunge Object: 219 Export Object: 221 File Append Component: 222 File System Available: 222 File Check and Repair: 223 File Copy: 224 File Create: 226 File Drop Component: 228 File Erase: 229 File History: 229 File Hold: 231 Fix Script: 232 Component File Library: 233 Format (Monadic): 234 Format (Dyadic): 235 File Names: 242 File Numbers: 243 File Properties: 244 Floating-Point Representation: 247 File Read Access: 249 File Read Component Information: 250 File Read Component: 251 viii File Rename: 252 File Replace Component: 253 File Resize: 254 File Size: 255 File Set Access: 255 File Share Tie: 256 Exclusive File Tie: 257 File Untie: 258 Fix Definition: 258 Instances: 259 Index Origin: 260 Key Label: 261 Line Count: 261 Load Workspace: 262 Lock Definition: 263 Latent Expression: 264 Map File: 264 Migration Level: 266 Set Monitor: 268 Query Monitor: 269 Name Association: 270 Native File Append: 298 Name Classification: 299 Native File Create: 310 Native File Erase: 310 New Instance: 311 Name List: 312 Native File Lock: 316 Native File Names: 318 Native File Numbers: 318 Enqueue Event: 319 Nested Representation: 321 Native File Read: 322 Native File Rename: 324 Native File Replace: 324 Native File Resize: 326 Create Namespace: 326 Namespace Indicator: 328 Native File Size: 328 Native File Tie: 329 Null Item: 330 Native File Untie: 331 Native File Translate: 331 Sign Off APL: 332 Variant: 332 ix Object Representation: 333 Search Path: 337 Program Function Key: 339 Print Precision: 340 Profile Application: 341 Print Width: 348 Cross References: 349 Replace: 350 Random Link: 369 Space Indicator: 371 Response Time Limit: 372 Search: 372 Save Workspace: 372 Screen Dimensions: 373 Session Namespace: 373 Execute (UNIX) Command: 374 Start UNIX Auxiliary Processor: 375 State Indicator: 376 Shadow Name: 377 Signal Event: 378 Size of Object: 381 Screen Map: 382 Screen Read: 385 Source: 389 State Indicator Stack: 390 State of Object: 391 Set Stop: 393 Query Stop: 394 Set Access Control: 395 Query Access Control: 396 Shared Variable Offer: 397 Query Degree of Coupling: 399 Shared Variable Query: 399 Shared Variable Retract Offer: 400 Shared Variable State: 401 Terminal Control: 402 Thread Child Numbers: 403 Get Tokens: 403 This Space: 405 Current Thread Identity: 406 Kill Thread: 406 Current Thread Name: 407 Thread Numbers: 407 Token Pool: 407 Put Tokens: 408 x Set Trace: 409 Query Trace: 410 Trap Event: 411 Token Requests: 415 Time Stamp: 416 Wait for Threads to Terminate: 417 Unicode Convert: 418 Using (Microsoft .Net Search Path): 421 Vector Representation: 422 Verify & Fix Input: 423 Workspace Available: 424 Windows Create Object: 425 Windows Get Property: 428 Windows Child Names: 429 Windows Set Property: 430 Workspace Identification: 431 Window Expose: 432 XML Convert: 433 Extended State Indicator: 447 Set External Variable: 448 Query External Variable: 450 Chapter 4: System Commands 451 Introduction 451 List Classes: 453 Clear Workspace: 453 Windows Command Processor: 454 Save Continuation: 455 Copy Workspace: 456 Change Space: 458 Drop Workspace: 458 Edit Object: 459 List Events: 460 List Global Defined Functions: 460 Display Held Tokens: 461 List Workspace Library: 462 Load Workspace: 463 List Methods: 464 Create Namespace: 464 List Global Namespaces: 465 List Global Namespaces: 465 Sign Off APL: 465 List Global Defined Operators: 465 Protected Copy: 466 xi List Properties: 467 Reset State Indicator: 467 Save Workspace: 467 Execute (UNIX) Command: 469 State Indicator: 470 Clear State Indicator: 471 State Indicator & Name List: 471 Thread Identity: 472 List Global Defined Variables: 473 Workspace Identification: 473 Load without Latent Expression: 474 Chapter 5: Error Messages 475 Introduction 475 Standard Error Action 476 APL Errors 477 Operating System Error Messages 481 Windows Operating System Error Messages 483 APL Error Messages 484 bad ws 484 cannot create name 484 clear ws 484 copy incomplete 484 DEADLOCK 484 defn error 485 DOMAIN ERROR 486 EOF INTERRUPT 486 EXCEPTION 486 FIELD CONTENTS RANK ERROR 487 FIELD CONTENTS TOO MANY COLUMNS 487 FIELD POSITION ERROR 487 FIELD CONTENTS TYPE MISMATCH 487 FIELD TYPE BEHAVIOUR UNRECOGNISED 487 FIELD ATTRIBUTES RANK ERROR 487 FIELD ATTRIBUTES LENGTH ERROR 487 FULL SCREEN ERROR 487 KEY CODE UNRECOGNISED 488 KEY CODE RANK ERROR 488 KEY CODE TYPE ERROR 488 FORMAT FILE ACCESS ERROR 488 FORMAT FILE ERROR 488 FILE ACCESS ERROR 489 FILE ACCESS ERROR CONVERTING 489 FILE COMPONENT DAMAGED 489 xii FILE DAMAGED 490 FILE FULL 490 FILE INDEX ERROR 490 FILE NAME ERROR 490 FILE NAME QUOTA USED UP 491 FILE SYSTEM ERROR 491 FILE SYSTEM NO SPACE 491 FILE SYSTEM NOT AVAILABLE 491 FILE SYSTEM TIES USED UP 491 FILE TIE ERROR 492 FILE TIED 492 FILE TIED REMOTELY 492 FILE TIE QUOTA USED UP 493 FORMAT ERROR 493 HOLD ERROR 493 incorrect command 494 INDEX ERROR 494 INTERNAL ERROR 495 INTERRUPT 495 is name 495 LENGTH ERROR 496