Javascript: enumerate skews and rotations with multiple loop increments -

this question related another question think it's answer doesn't cover problem. have following:

var props = ['skew','rotate'],      axis = ['x','y','z'];  (var p=0, a=0; p<2, a<3; p++, a++){     console.log(props[p]+axis[a]) } 

why logs undefinedx?

update: log should write rotatex rotatey rotatez skewx skewy skewz.

you use inner , outer loop enumerate combinations

var props = ['skew','rotate']  ,   axis = ['x','y','z']  ,   result = '';    for(prop = 0; prop < props.length; prop ++) {      for(dir = 0; dir < axis.length; dir ++) {          result += props[prop] + axis[dir] + '<br/>';      }  }  document.write(result);

the problem using single loop 2 arrays of different sizes both variables incremented long code hasn't reached end of 1 array.

now fixed checking in loop , capping index in array @ length - 1 of array.

however, bigger problem in using approach aren't concatenating each value in first array each variable in second array. concatenating each value first array @ position corresponding value second array @ same position.