Re: Can you tell me what is wrong with this program

*To*: mathgroup at smc.vnet.net*Subject*: [mg110347] Re: Can you tell me what is wrong with this program*From*: Bill Rowe <readnews at sbcglobal.net>*Date*: Tue, 15 Jun 2010 02:27:05 -0400 (EDT)

>c = 0; >m = 0; >z = 0; >count = 0; >for [lc = 0, lc < 8, lc++] >{ >lc = lc + 1; >for[lm = -4, lm < 8, lm++] >{ >lm = lm + 1; >for [lz = -4, lz < 8, lz++] >{ >lz = lz + 1; >A = (2*(lc - lm)*(lc - lm)) + 4*lz*lz; >B = -2*(lc + lm)*lz; >C = 4*lc*lm; >if [A > 0] >if[(B*B - A*C) > 0] >{ >K1 = (B + sqrt (B*B - A*E))/A; >K2 = (B - sqrt (B*B - A*E))/A; >e = abs (lc); >m = abs (lm); >z = abs (lz); >L = c + m + z; >if [K1 <= 0.707 && K1 > 0 , print[n, L, lc, lm , lz, K1]] >if [K2 <= 0.707 && K1 > 0 , print[n, L, lc, lm , lz, K2]] > >} > > >} >} >} >I get the following error >Out[5]= for[0, True, 0] >During evaluation of In[1]:= Set::wrsym: Symbol C is Protected. >> Let's start with *all* built-in Mathematica functions start with an uppercase letter. No exceptions. Next, arguments to all functions are delimited with *square* brackets "[" and "]" not parentheses. So your abs(lc) needs to be Abs[lc] etc. And since there are several built-in things named with a single uppercase letter such as C,D and E, you would be well advised to not use a single upper case letter as a variable name.