How to write height for row in RxSwift?

I want to convert the below code into RxSwift. And also please help me how to write button Action code in RxSwift.

ReactiveCocoa or RxSwift Which one is better to use in swift3?

func tableView(_ tableView: UITableView, numberOfRowsInSection section: 
Int) -> Int {
    return posts.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: 
IndexPath) -> UITableViewCell {
    let cell: BTSTableViewCell = self.tableView.dequeueReusableCell(withIdentifier: "BTSTableViewCellIdentifier")! as! BTSTableViewCell

    cell.configureWithPost(posts[indexPath.row])
    cell.delegate = self
    return cell

}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {

    // 259.5+ labelHeight+ bigImageHeight

    let postViewModel = posts[indexPath.row]

    //caption height
    var captionHeight = postViewModel.textDetail?.height(withConstrainedWidth: tableView.bounds.size.width - 20, font: UIFont.systemFont(ofSize: 17))

    captionHeight = ceil(captionHeight!)

    var finalCaptionHeight: CGFloat = 0.0;

   if postViewModel.showDetailedCaption {
        finalCaptionHeight = captionHeight!
    }
    else {
        finalCaptionHeight = min(41, captionHeight!)
    }
    return 259.5 + 
 postViewModel.getBigImageHeightFor(tableView.bounds.size.width) + 
 finalCaptionHeight

}

For tableview in RxSwift, take look at : https://github.com/devxoul/help-me-rx-tableview-cell-height/blob/master/SimpleTableViewController/SimpleTableViewController.swift

for the button action check sample code below

button.rx.tap
        .bind { [weak self] in
            //YOUR TAP ACTION CODE LOGIC GOES HERE
        }
        .disposed(by: disposeBag)