Re: How do you get Mathematica to evaluate "Floor" to give a number?
- To: mathgroup at smc.vnet.net
- Subject: [mg109063] Re: How do you get Mathematica to evaluate "Floor" to give a number?
- From: David Bailey <dave at removedbailey.co.uk>
- Date: Mon, 12 Apr 2010 06:53:37 -0400 (EDT)
- References: <hpplek$m7n$1@smc.vnet.net>
John Ertle Jr. wrote: > In[1]:= J = 367*y + Floor (7*(y + Floor ((m + 9)/12))/4) + Floor (275*m/9) + > da + 1721013.5 > > Out[1]:= 2.44254*10^6 + (2200 Floor)/9 + 7/4 Floor (1966 + (17 Floor)/12) > > How do you get Mathematica to evaluate "Floor" to give a number? > Every Mathematica function - including Floor - uses square brackets to denote the argument list. This is because ordinary algebraic notation is ambiguous: f(a+b) can mean f*a + f*b, or it can refer to the function f. Clearly this ambiguity must be resolved for computer algebra, and in Mathematica, the above expression would mean f*a+f*b, and to refer to a function f, one must write f[a+b]. If you write your expressions that way, AND provide values for the various variables in your expression, you will get a numeric answer. If I have difficulty with a built in function - such as Floor - my first approach is to click on the name of the function, and press F1 to get the help for that function. This will give you examples of actual use, that you can paste into your notebook and change progressively into whatever you require. David Bailey http://www.dbaileyconsultancy.co.uk