Rijy=RijCos theta if i<j and -RijCos theta if i>j
Thanks buddies!
More directly, something like
In[9]:= f[i_, j_, \[Theta]_] := R[i, j] Cos[\[Theta]] Sign[j - i] In[10]:= f[1, 2, \[Theta]] Out[10]= Cos[\[Theta]] R[1, 2] In[11]:= f[2, 1, \[Theta]] Out[11]= -Cos[\[Theta]] R[2, 1]
Thanks buddy!
I like to do it this way:
In[1]:= func[i_, j_] := If[i < j, 2 i + j, i + 3 j] In[2]:= func[1, 2] Out[2]= 4 In[3]:= func[2, 1] Out[3]= 5
Erivaldo, look at the documentation for Condition (usually written "/;"). Not sure what your experience with Mathematica is, so I'll also mention that functions are typically defined using SetDelayed (":=").
A conditional function definition might look like this:
In[1]:= func[i_, j_] := 2 i + j /; i < j In[2]:= func[i_, j_] := i + 3 j In[3]:= func[1, 2] Out[3]= 4 In[4]:= func[2, 1] Out[4]= 5
thanks buddy!
