Perhaps, I should explain that certain terms in the
C version of transposeSquare are really constants. For
example, if the argument is i. 9, then
%:@# is width or 3
# is width*height or 9
I hope that helps.
On Mon, 28 Jan 2013, Brian Schott wrote:
I am trying to use objective C and am using j to develop some pieces. I
have the verb `transposeSquare` which transposes a square matrix's indices using
indices and reproduces j's Transpose. In C code the indices are named ii and are
being generated in a for loop as follows, where width and height are actually
both 13 but my j examples use 3 instead of 13.
for (int ii = 0 ; ii < width * height ; ++ii)
transposeSquare =: (] <.@% %:@#)+#| %:@# *]
transposeSquare i. 9
0 3 6 1 4 7 2 5 8
,|:i. 3 3 NB. this is the "J way"
0 3 6 1 4 7 2 5 8
Now with C code for loop in mind I need a verb which first does what
transposeSquare does and then reverses the indices using the operators available
to C so that the result of the verb would be as follows.
,|.|:i. 3 3 NB. this is the "J way"
2 5 8 1 4 7 0 3 6
That is, I need a verb (say, reverseOfTranspose, rOT), which gives the
same result as ,|.|:i. 3 3 but with the scalar argument 3 and is limited to C
operators.
(B=)
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