What is the object equivalent of _.pluck

I've re-implemented my own version of what I need but I suspect this is already included in underscore since it's so simple and so closely related to many other functions. But I can't think of what it should be called. Basically, what I want is a version of _.pluck that works with objects and returns an object instead of an array (with its associated keys). So, for instance, if I had an object like this: ``` elements: { steam: { temperature: 100, color: 'orange', state: 'gas' }, water: { temperature: 50, color: 'blue', state: 'liquid' }, ice: { temperature: 0, color: 'white', state: 'solid' } } ``` I'd want to call `_.something(elements, 'temperature')` And have it return ``` { steam: 100, water: 50, ice: 0 } ``` Instead of `_.pluck(elements, 'temperature')` which returns ``` [100, 50, 0] ``` What is this transformation called and is it already included in underscore? I've written a quick version myself with jQuery's each loop since I'm more familiar with jQuery than underscore (included below) but would prefer to use one from the library if possible. ``` $.objPluck = function(obj, key) { var ret = {}; $.each(obj, function(k, value) { ret[k] = value[key]; }); return ret; } ```