BASE64=: (a.{~ ,(a.i.'Aa') +/i.26),'0123456789+/'
tobase64=: 3 : 0
res=. BASE64 {~ #. _6 [\ , (8#2) #: a. i. y
res, (0 2 1 i. 3 | # y) # '='
)
tob64 =: ('=' #~ 0 2 1 i. 3 | # ) ,~ BASE64 {~ [: #. _6 ]\ (8#2) ,@:#:
a.&i.
tb64 =: 3 : '(''='' #~ 0 2 1 i. 3 | # y) ,~ BASE64 {~ #. _6 ]\ (8#2)
,@:#: a.&i. y'
frombase64=: 3 : 0
pad=. _2 >. (y i. '=') - #y
pad }. a. {~ #. _8 [\ , (6#2) #: BASE64 i. y
)
fb64 =:a. {~ [: #. _8 [\ (6#2) ,@:#: BASE64&i. }.~ _2 >. # -~ i.&'='
tobase64 is original code from addon. It is explicit with a temporary
variable. tb64 is also explicit but without the temp var. tob64 is a tacit
version.
a =. 100000 $ a.
timespacex 'tob64 a'
0.0312112 1.78275e7
timespacex 'tobase64 a'
0.0277369 2.85809e7
timespacex 'tb64 a'
0.0289411 2.04608e7
all are impressively fast, but the 2 explicit functions are faster, and somehow
the one with a temp variable is fastest.
the tacit version does use less space, as well as the one line tacit entry.
Its also faster for array item application
timespacex 'tob64"1 ] 100 1000 $ a'
0.0154246 539264
timespacex 'tobase64"1 ] 100 1000 $ a'
0.016376 628736
Its also surprising though that applying the function to 100 smaller items is
faster than the whole.
Any insights on why this is happening?
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