**Note:**

The clues for the new crossword contain some APL characters. These are coded as APL2741 (available as a 45K download), and also with <CODE> tags. The mapping is compatible with both the APL2000 font and the current Dyalog font.

## Solution to APL Crossword from 15.1

## Crossword from 15.2

**Across**

1. Reverse the elements in the vector `L`

4. Delete from the vector `N`

the even numbers 2 to 100

9. Scale up the numbers in the matrix `M`

by 100000, and return as a vector

12. Fifty-five fives

13. The sum of the absolute value of the vector `NV`

summed with the magnitudes of the first `R`

elements of `V`

16. The `N`

by `N`

identity matrix (1s on the diagonal)

17. Get outta here!

18. Flag the rows of the 15-column character matrix `CMI`

that match the first fifteen elements of `CV`

20. A random positive integer no more than 20 bigger than `A`

21. The amount to subtract from `T`

to make it the next higher integer

23. Given `N`

, a vector of integers, map all values from 1 to 7 to the numbers 0 to 6

26. Find the first four in `F`

fast

27. What’s currently localized?

28. Transform the matrix of scores `S`

from students by exams, to exams by students and cap the scores at 100

30. `(N+1)-¼N`

, without using `²`

31. Squeeze all 0s from the vector `V`

34. `(½M)½(1‡½M)/V`

for the matrix `M`

and the vector `V`

37. `E`

(bits) if the vector `N`

is empty, otherwise `(½E)½1`

38. Divide each row of `NM`

by the vector `E`

, where `S„½NM`

39. Repeat each column of `M`

, `C`

times

40. `(½M)½(0)`

, for character `M`

41. `3²2/2½'ICE CREAM'`

**Down**

1. `2-(½VEC¼n[²¼C]`

in origin 1

2. Convert the bit vector `LE`

, having length `M`

, to the designated indices

3. Flag those values of `A`

that are contained in the matrix `NT`

and for which the corresponding values in the non-negative integer array `N`

are nonzero

4. How many 27s are there in each row of the matrix `NM`

?

5. `1 2 3 4 5`

, five times

6. From the first `N`

values in `T`

, flag those that aren’t multiples of five

7. The indices of the vector `V`

8. `1ƒ¼10`

10. Generate `NI`

( a multiple of 5) random numbers between 0 and 4, having the same frequency of each value

11. `(V[1]+¼L),(V[2]+¼L),(V[3]+¼L), ...`

14. Which elements in `R`

are 10s?

15. `+/¼4`

17. Branch to the line labelled `V`

if `I`

is a scalar

19. `-F1-C`

22. `–�„'T',0½T„40`

24. Change the sign of `S`

25. A random index into the vector `S`

, up to the index at which the shape of `M`

is found

28. Transpose the matrix `NM`

along the MINOR diagonal

29. The number of whole multiples of `C`

in `NM`

32. None

33. `(½M)½0`

, for numeric `M`

34. Transform `NM`

from shape (6 3 4) to shape (4 3 6)

35. Unfinished business

36. If `MAT`

were demoted

Reprinted with kind permission from Zark APL Tutor News, a quarterly publication of Zark Incorporated, 23 Ketchbrook Lane, Ellington, CT06029, USA