I found multiple similar questions, but cannot get how to do the following: 

I get this type of data from server:

```
test_data = {
        '222': {
            joy: 66.5057373046875,
            fear: 1.0003513832343742,
            anger: 2.000018799044483,
            disgust: 3.004251452162862,
            sadness: 4.0001135088386945,
            contempt: 5.001299204188399,
            surprise: 6.203749045729637
        },
        '238': {
            joy: 97.06363677978516,
            fear: 17.500137131541123,
            anger: 27.00000593749519,
            disgust: 6.001324078417383,
            sadness: 21.000043172625737,
            contempt: 21.00033742573578,
            surprise: 32.62530106306076
        },
        '722': {
            joy: 66.5057373046875,
            fear: 60.000351383234374,
            anger: 70.00001879904448,
            disgust: 10.004251452162862,
            sadness: 92.0001135088387,
            contempt: 40.0012992041884,
            surprise: 50.20374904572964
        }
    }

```

What I need is to create an array for every object inside the `test_data` object, for example, `joyArray` to hold all `joy` values, `fearArray` all `fear` values, etc.. Example:

```
joyArray = [66.5057373046875, 97.06363677978516, 66.5057373046875]

```

I am not sure how to do this, I tried to play around with `Object.keys` but didn't manage to do it. Any advice?