提取列名(这是这里的棘手部分，因为它无法在闭包中计算):

Extract columns names (this is the tricky part here because it cannot be evaluated in the closure):

val names = df.columns

和 map 条目:

simsPerfect.entries.map {
  case MatrixEntry(i, j, v)  => (names(i.toInt),  names(j.toInt), v)
}