Burrows–Wheeler transform: Difference between revisions
→{{header|Sidef}}
Line 918:
***error*** BWT: The input string contains an invalid character at position 15.
</pre>
=={{header|Scala}}==
{{trans|Kotlin}}
<lang scala>import scala.collection.mutable.ArrayBuffer
object BWT {
val STX = '\u0002'
val ETX = '\u0003'
def bwt(s: String): String = {
if (s.contains(STX) || s.contains(ETX)) {
throw new RuntimeException("String can't contain STX or ETX")
}
var ss = STX + s + ETX
// val table = Array<String>(ss.length) { ss.substring(it) + ss.substring(0, it) }
var table = new ArrayBuffer[String]()
(0 until ss.length).foreach(_ => {
table += ss
ss = ss.substring(1) + ss.charAt(0)
})
// return String(table.map { it[it.lastIndex] }.toCharArray())
table.sorted.map(a => a.last).mkString
}
def ibwt(r: String): String = {
var table = Array.fill(r.length)("")
(0 until r.length).foreach(_ => {
(0 until r.length).foreach(i => {
table(i) = r.charAt(i) + table(i)
})
table = table.sorted
})
table.indices.foreach(i => {
val row = table(i)
if (row.last == ETX) {
return row.substring(1, row.length - 1)
}
})
""
}
def makePrintable(s: String): String = {
s.replace(STX, '^').replace(ETX, '|')
}
def main(args: Array[String]): Unit = {
val tests = Array("banana",
"appellee",
"dogwood",
"TO BE OR NOT TO BE OR WANT TO BE OR NOT?",
"SIX.MIXED.PIXIES.SIFT.SIXTY.PIXIE.DUST.BOXES",
"\u0002ABC\u0003"
)
tests.foreach(test => {
println(makePrintable(test))
print(" --> ")
try {
val t = bwt(test)
println(makePrintable(t))
val r = ibwt(t)
printf(" --> %s\n", r)
} catch {
case e: Exception => printf("ERROR: %s\n", e.getMessage)
}
println()
})
}
}</lang>
{{out}}
<pre>banana
--> |annb^aa
--> banana
appellee
--> |e^elplepa
--> appellee
dogwood
--> |do^oodwg
--> dogwood
TO BE OR NOT TO BE OR WANT TO BE OR NOT?
--> |?OOORREEETTRTW BBB ATTT NNOOONOO^
--> TO BE OR NOT TO BE OR WANT TO BE OR NOT?
SIX.MIXED.PIXIES.SIFT.SIXTY.PIXIE.DUST.BOXES
--> |STEXYDST.E.IXXIIXXSSMPPS.B..EE.^.USFXDIIOIIIT
--> SIX.MIXED.PIXIES.SIFT.SIXTY.PIXIE.DUST.BOXES
^ABC|
--> ERROR: String can't contain STX or ETX</pre>
=={{header|Sidef}}==
| |||