Re: Multiple Constants

*To*: mathgroup at smc.vnet.net*Subject*: [mg83262] Re: Multiple Constants*From*: Steven Siew <siewsk at bp.com>*Date*: Fri, 16 Nov 2007 05:32:40 -0500 (EST)*References*: <fhh80l$946$1@smc.vnet.net>

The following sequence of mathematica script will set the variables to have the attribute Constant. First we show that the variables b and c are just normal variables. Then we set their attributes to Constant. And lastly we show that their attributes has changed. Steven Siew Attributes[b] Attributes[c] listofconstants = {b, c, d, A, f, g, h, Q} Map[SetAttributes[#, Constant] &, listofconstants] Attributes[b] Attributes[c] On Nov 15, 9:45 pm, thehammers... at gmail.com wrote: > Hi, > I'm new to Mathematica and I feel like this is a stupid question but I > can't seem to define more than one constant > > If I type > SetAttributes[a,b,c,Contstant] > I get > SetAttributes::argrx: SetAttributes called with 4 arguments; 2 > arguments are \expected. > > I have three equations and three variables I want to solve for and I > have 8 constants. > > x+y+z=1 > b*x+c*y+d*z=A > f*x+g*y+h*z=Q > > b,c,d,A,f,g,h,Q are constants and I want a generic equations that I > can use for many different variations of these constants. > > I've done the calculation by hand but fear I have made a mistake and > would like to double check my calculation, and then use the equation > to propagate my errors, as each constant has an associated standard > error of the mean. Propagation of my error will give me an error on my > model calculation, which is really important. > > Thanks