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 | erratum_type | Comment |
|---|---|---|---|
| Intro | 3 | 1 | Utilities and Data "WorkSpace" should be "workspace" |
| Intro | 3 | 2 | Utilities and Data DyalogTutor_EN should be in the index. |
| Intro | 4 | 1 | Penultimate paragraph "justifyable" should be "justifiable". |
| Intro | 10 | 2 | 2nd paragraph Alter to read "..the other symbols (...) we have discussed so far are called.." |
| Intro | 16 | 1 | First line Remove extraneous "that" in first line. |
| Intro | 29 | 1 | 2nd bullet point, last line Add "is" in "there __ no need .." |
| A | 36 | 1 | 1.3.1 end of 1st paragraph
Add "," in "in the same way as__ for .." |
| A | 36 | 4 | 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 | 2 | 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←{} a b←1 2 b 1 2 For that reason the () in the assignment statement are strongly recommended. |
| B | 51 | 3 | 3.2
"A single number has no dimensions" .. what about ⍴,1 ? |
| B | 56 | 1 | Display of MonVec
There should be two spaces between "March" and "April", as between the other months. |
| B | 61 | 2 | 5.5.2
Quicker than Text[;1]←0 would be Text←(⍴Text)⍴0 and similarly for Vector. |
| B | 62 | 1 | 5.6
4 2 ⌷ Tests returns 40, not 78. |
| B | 65 | 2 | penultimate paragraph
Suggest "but it will not be long before you understand immediately what it means." |
| B | 71 | 2 | 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 | 1 | Penultimate bullet point
"which is equivalent to ""Save As""". |
| B | 71 | 1 | last bullet point remove "," after "APL". |
| B | 75 | 1 | 8.4 First sentence
dws, which stands for Dyalog WorkSpace. |
| B | 87 | 2 | SPE-6
Explain further the uses of Monadic Index. |
| B | 87 | 1 | Penultimate paragraph
Extra "a" in the sentence "Applied to a an Enumerable .." |
| C | 96 | 1 | Last paragraph of Warning!
Should read "why we recommend that you do all .." (remove "to"). |
| C | 110 | 1 | Row-wise multiplication
Second example should read "Tam×[1]5 2 7" - not 5 2 10 |
| C | 121 | 1 | 12.1 Example
Font wrong in comment "We ask for the positions of 5"; "ask" and "the positions of" too big. |
| D | 152 | 4 | 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 | 4 | 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 | 1 | 1/2 way down page
"all we need do is replace..". Add "to". |
| D | 171 | 4 | If condition 1
The comment to the right of "Block 1" should read: "Executed if Condition 1 is satisfied" |
| D | 181 | 1 | First line of 4.6.1 and 4.6.2
"In any kind of loop" is in too-small a font. |
| D | 190 | 4 | Jump if true..
The expression →Destination×⍳Condition works only if ⎕io is 1. |
| D | 203 | 2 | 1/2 way down page
Should Prompt1[1] be ⎕←'What are the limits' ? |
| D | 204 | 2 | Hint
Another alternative is to type → |
| D | 216 | 4 | 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 | 2 | Throughout page
Rather than Activating a menu option, it should be selected. This may occur elsewhere in the book. |
| D | 236 | 1 | First paragraph or Spe-7
Remove "," immediately before last ;InEach. |
| E | 239 | 1 | 4th paragraph
"he may be able to restart the program" .. better to say "he may be able to resume or continue .." |
| E | 241 | 2 | last line of 1.1.2
"or until we explicitly clear it by using )reset". |
| E | 244 | 2 | the word obtuse
might be considered obtuse :-) |
| E | 249 | 2 | ×/ ⍳Max
If Max is too big, the result would be larger than the largest number that Dyalog APL can hold. |
| E | 249 | 1 | 1.3 )SI
Formatting wrong for )SI |
| E | 262 | 1 | First paragraph, last line
"sometimes names Stops" should be "sometimes named Stops". |
| F | 286 | 1 | 4G⊂ ZZZ9' ⎕FMT MN
Comma unnecessary in commentary, which itself is incorrectly formatted. |
| F | 288 | 1 | 3.2.8 penultimate example
Commentary incorrectly formatted. |
| F | 289 | 1 | 3.3.2 first example
Commentary incorrectly formatted. |
| G | 302 | 3 | 1.2.1 first paragraph last line
"dynamic function" .. dfn or what ?? |
| G | 308 | 1 | 2.2.1 second paragraph
"Take a look to" s/b "Take a look at". |
| I | 335 | 1 | 2nd bullet point
Remove first "one" from "items one from one another" |
| I | 344 | 4 | Penultimate paragraph
"more workspace than we have room for." Better "more workspace than is available." |
| I | 359 | 1 | After definitions
First occurrence of hogwash is spelled hoqwash(sic). |
| I | 369 | 1 | Penultimate paragraph, last line
One too many "then"s at the start of the line. |
| J | 390 | 1 | 2 -/ Cum
should return one fewer element than Cum-1↓Cum,0 So 2 -/ Cum 56 32 56 104 63 38 37 2 -/ +/ Limits ∘.< Ages 56 32 56 104 63 38 37 |
| I | 418 | 4 | 8.5 title
What is a fixpoint ? |
| J | 422 | 2 | 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 | 4 | 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 | 4 | 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 | 4 | Solution to C-1
The result of the second expression of C-1 is incorrect: 12 6 27 ⌊ 11 + ⍳3 12 6 14 |
| X | 772 | 4 | 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 | 1 | First sentence
.. are not developed .. |