Mastering Dyalog APL Errata
No book is entirely free of errors; the ones that we know about are listed below. If you find a new item of interest and would like to report it, then e-mail us.
| Chapter | Page | Type | Comment |
|---|---|---|---|
| Intro | 3 | Typo |
Utilities and Data "WorkSpace" should be "workspace" |
| Intro | 3 | Suggestion |
Utilities and Data DyalogTutor_EN should be in the index. |
| Intro | 4 | Typo |
Penultimate paragraph "justifyable" should be "justifiable". |
| Intro | 10 | Suggestion |
2nd paragraph Alter to read "..the other symbols (...) we have discussed so far are called.." |
| Intro | 16 | Typo |
First line Remove extraneous "that" in first line. |
| Intro | 29 | Typo |
2nd bullet point, last line Add "is" in "there __ no need .." |
| A | 36 | Typo |
1.3.1 end of 1st paragraph Add "," in "in the same way as__ for .." |
| A | 36 | Content | The workspace DyalogTutor_EN.dws can no longer be reached by following the link to http://www.dyalog.com/intro. Instead,go to http://www.dyalog.com/mastering-dyalog-apl.htm – there's a link to "companion files" in the second paragraph that allows you to download a zip file containing the DyalogTutor_EN.dws and other files. |
| A | 46 | Suggestion |
End of 1.3 : Clarity in the last paragraph: It should be pointed out that clarity is an issue as well: with a b←1 2 one cannot say what is going to happen. a and b may be variables holding a 1 and a 2, but the expression might also create a variable b which holds 1 and 2 because a is a monadic function that does not return an argument. a←{} For that reason the () in the assignment statement are strongly recommended. |
| B | 51 | Debate |
3.2 "A single number has no dimensions" .. what about ⍴,1 ?
|
| B | 56 | Typo |
Display of MonVec There should be two spaces between "March" and "April", as between the other months. |
| B | 61 | Suggestion |
5.5.2 Quicker than Text[;1]←0 would be Text←(⍴Text)⍴0 and similarly for Vector.
|
| B | 62 | Typo |
5.6 4 2 ⌷ Tests returns 40, not 78.
|
| B | 65 | Suggestion |
penultimate paragraph Suggest "but it will not be long before you understand immediately what it means." |
| B | 71 | Suggestion |
Remark Consider adding a reference to G-1.1.5 or I.7 which explain the difference between empty numeric and character vectors. |
| B | 71 | Typo |
Penultimate bullet point "which is equivalent to ""Save As""". |
| B | 71 | Typo |
last bullet point remove "," after "APL". |
| B | 75 | Typo |
8.4 First sentence dws, which stands for Dyalog WorkSpace. |
| B | 87 | Suggestion |
SPE-6 Explain further the uses of Monadic Index. |
| B | 87 | Typo |
Penultimate paragraph Extra "a" in the sentence "Applied to a an Enumerable .." |
| C | 96 | Typo |
Last paragraph of Warning! Should read "why we recommend that you do all .." (remove "to"). |
| C | 110 | Typo |
Row-wise multiplication Second example should read " Tam×[1]5 2 7" - not 5 2 10
|
| C | 121 | Typo |
12.1 Example Font wrong in comment "We ask for the positions of 5"; "ask" and "the positions of" too big. |
| D | 152 | Content |
Sesction 2.1 The statement "The arguments ⍵ and ⍺ are read-only" is not precise. Assignment to ⍺ occurs if the dfn which contains the assignment is called monadically; it is the syntax used to define an ambivalent dfn.
|
| D | 156 | Content |
Section 3.2 This section is written with the assumption that the variable res, which was created when you ran Meanval before adding res← to the function header, has been deleted. When you first ran the function, since res did not appear in the header, it was created as a global variable. You haven't been asked to delete it so far, so it still exists. To make this section more understandable, type )erase res before trying the code ! |
| D | 166 | Typo |
1/2 way down page "all we need do is replace..". Add "to". |
| D | 171 | Content |
If condition 1 The comment to the right of "Block 1" should read: "Executed if Condition 1 is satisfied" |
| D | 181 | Typo |
First line of 4.6.1 and 4.6.2 "In any kind of loop" is in too-small a font. |
| D | 190 | Content |
Jump if true.. The expression →Destination×⍳Condition works only if ⎕io is 1.
|
| D | 203 | Suggestion |
1/2 way down page Should Prompt1[1] be ⎕←'What are the limits' ?
|
| D | 204 | Suggestion |
Hint Another alternative is to type →
|
| D | 216 | Content |
At end of section Note that with a dfn the assignment does not create a synonym, but rather creates a new independent dfn which can be edited using the function editor. |
| D | 222 | Suggestion |
Throughout page Rather than Activating a menu option, it should be selected. This may occur elsewhere in the book. |
| D | 236 | Typo |
First paragraph or Spe-7 Remove "," immediately before last ;InEach. |
| E | 239 | Typo |
4th paragraph "he may be able to restart the program" .. better to say "he may be able to resume or continue .." |
| E | 241 | Suggestion |
last line of 1.1.2 "or until we explicitly clear it by using )reset".
|
| E | 244 | Suggestion |
the word obtuse might be considered obtuse 🙂 |
| E | 249 | Suggestion |
×/ ⍳Max If Max is too big, the result would be larger than the largest number that Dyalog APL can hold.
|
| E | 249 | Typo |
1.3 )SI Formatting wrong for )SI
|
| E | 262 | Typo |
First paragraph, last line "sometimes names Stops" should be "sometimes named Stops". |
| F | 286 | Typo |
4G⊂ ZZZ9' ⎕FMT MN Comma unnecessary in commentary, which itself is incorrectly formatted. |
| F | 288 | Typo |
3.2.8 penultimate example Commentary incorrectly formatted. |
| F | 289 | Typo |
3.3.2 first example Commentary incorrectly formatted. |
| G | 302 | Debate |
1.2.1 first paragraph last line "dynamic function" .. dfn or what ?? |
| G | 308 | Typo |
2.2.1 second paragraph "Take a look to" s/b "Take a look at". |
| I | 335 | Typo |
2nd bullet point Remove first "one" from "items one from one another" |
| I | 344 | Content |
Penultimate paragraph "more workspace than we have room for." Better "more workspace than is available." |
| I | 359 | Typo |
After definitions First occurrence of hogwash is spelled hoqwash(sic). |
| I | 369 | Typo |
Penultimate paragraph, last line One too many "then"s at the start of the line. |
| J | 390 | Typo |
2 -/ Cum should return one fewer element than Cum-1↓Cum,0 So 2 -/ Cum 2 -/ +/ Limits ∘.< Ages
|
| I | 418 | Content |
8.5 title What is a fixpoint ? |
| J | 422 | Suggestion |
10.1.2 1. Replace "function editor" with "editor" .. it's the same editor, no matter what's being edited. 2. Would the word "Signature" be better than "possible header structures" ? |
| K | 443 | Content |
Calculating Positions in a Matrix In the first block of text on p443 the text reads "we can employ Decode ..". That is incorrect - the text should read "we can employ Encode ..". |
| P | 629 | Content |
GUI_List function For the example and the text to work, GUI_List[5] should read [5] ⍝ 'Win.show'⎕WS 'Event' 'Select' 'ShowSel' although the parentheses are superfluous. |
| X | 758 | Content |
Solution to C-1 The result of the second expression of C-1 is incorrect: 12 6 27 ⌊ 11 + ⍳3
|
| X | 772 | Content |
Solution to K-11 The algorithms used for matrix division and inverse have been improved in Version 13.0 onwards. As a result of these improvements, the values of abc are closer to 2 ¯0.5 3.5 and therefore 3 5 ¯1+.×abc returns 0 in 13.0 onwards. |
| Appendix 8 | 783 | Typo |
First sentence .. are not developed .. |
