# Converting a quantity to a decimal form [closed]

I have a function giving me this:

(5 Coulomb)/(6 Second)


as output. I want this in decimal form and would like to have the variables taken off the end for unit analysis. How would I do this? I have tried NumberForm, but I think that the unassigned variables I am using for units are throwing it off.

EDIT: Here is what I have for code

In[1]: f[P_, V_] := P/V
In[2]: f[100 W, 120 V]
Out[2]:(5 Coulomb)/(6 Second)


In[1]: f[P_, V_] := P/V
In[2]: f[100 W, 120 V]//N[#]&


And got:

Out[2]:(0.833333 Coulomb)/(Second)

• N[(5 coulomb)/(6 second)] gives me (0.833333 coulomb)/second. You could add /. {coulomb -> 1, second -> 1} at the end to get rid of the coulomb and second. – user484 Jul 6 '15 at 19:49
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• When I do Quantity[5, "Coulombs"]/Quantity[6, "Seconds"], then I don't get what you have. Could you make a small example and include code? More importantly, can you say what you mean by variables? I only see numbers and units.. – halirutan Jul 6 '15 at 19:50
• You have asked the same exact question again only 8 min after this one: How do I extract variables from an expression. You should not spam the site with duplicate questions. – MarcoB Jul 6 '15 at 20:08
• @MarcoB, read what I said in my post. I asked two separate questions, one per post, which is what you are supposed to do on StackExchange sites. One was about converting a number to decimal form and the other was about extracting units from an expression. – user3014065 Jul 6 '15 at 20:13

To be a bit more systematic, I would suggest declaring the units you want to work with in a global variable, and then defining a function unitsToUnity that sets all of those units to unity as follows:
$myUnits = {Coulomb, Second}; unitsToUnity[expression_] := expression /. Thread[$myUnits -> 1]