In August I wrote, 'One problem I have encountered is "invisible" leading unit axes.' Raul Miller responded with, '... Here's a cruder mechanism, which borrows from the apl2 display mechanism -- stuffing the shape of each array into its formatted representation.' Bob Therriault then suggested his addon 'jig' and Henry Rich's 'dissect', which display structural information when operating in the JQT environment.
Not wishing to spend a lot of time learning another layer of environment, I spent a lot of time instead on embellishing Raul's "mechanism", while gaining experience in the use of recursion--and noting the often disruptive prevalence of "invisible" leading unit axes, frequently encountered after opening boxed values. My script now resides in File:CTScan.ijs, offering a computerized tomographic scan of all the internal components of a J data value. It reports atop each subarray its depth, level, shape, and datatype. It offers options to constrain analysis to limited portions of the components, and to vary the format of the display. Additionally, the content-formatting routine, which performs some modest compaction in the display of certain types of higher-rank or nested arrays, can be called independently by other applications. Here are two brief examples; a greater variety will be found in the script's 'help' note: NB. Much of this structure is unclear in the default display, unlike the scan-- ] samp=: ((< (^ 1) , o. 1) ; 0 3 $ 'abc') ,: a: ; (<< i. 1 1 1 2) ┌─────────────────┬─────┐ │┌───────────────┐│ │ ││2.71828 3.14159││ │ │└───────────────┘│ │ ├─────────────────┼─────┤ │┌┐ │┌───┐│ │││ ││0 1││ │└┘ │└───┘│ └─────────────────┴─────┘ 1 1 1 CTScan samp ┌0\2: 2 2bx────────────────────────────┐ │┌1\1: bx──────────┐ ┌1\0: 0 3ch┐ │ ││┌2\0: 2fl───────┐│ └──────────┘ │ │││2.71828 3.14159││ │ ││└───────────────┘│ │ │└─────────────────┘ │ │┌1\1: bx───┐ ┌1\1: bx─────────┐│ ││┌2\0: 0bl┐│ │┌2\0: 1 1 1 2in┐││ │││ ││ ││0 1 │││ ││└────────┘│ │└──────────────┘││ │└──────────┘ └────────────────┘│ └──────────────────────────────────────┘ 0 0 0 CTScan samp ┌0\2: 2 2bx──────────────────── ┌1\1: bx────────┌1\0: 0 3ch ┌2\0: 2fl───────└────────── │2.71828 3.14159 └─────────────── ┌1\1: bx─ ┌1\1: bx─────── ┌2\0: 0bl ┌2\0: 1 1 1 2in │ │0 1 └──────── └────────────── Please send bug reports directly to an...@mit.edu. Complaints and suggestions for possible improvements, however, may deserve wider discussion. Thanks. --Art ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
