console 命令行工具 X clear
console
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Title</title>
</head>
<body>
<script>
  var json = {
    'a': {
      "f1": 1,
      "f2": 4,
      "f3": 7
    },
    'b': {
      "f1": 22,
      "f2": 5,
    },
    'c': {
      "f1": 3,
      "f2": 666,
      "f3": 9
    }
  }
  document.writeln ( '<pre>' + JSON.stringify(json, null, 2) + '</pre>' )
  document.writeln ( '<pre>' + JSON.stringify(transformRowColumn(json), null, 2) + '</pre>' )

  function transformRowColumn( json ) {
    var result     = {}
    Object.keys(json).forEach(function (rowName) {
      var row = json[rowName]
      Object.keys(row).forEach(function (columnName) {
        result[columnName] = result[columnName] || {}
        var column = row[columnName]
        result[columnName][rowName] = column
      })
    })
    return result
  }
  
</script>
</body>
</html>