General--Difficulties in Understanding Mathematica Syntax

• To: mathgroup at smc.vnet.net
• Subject: [mg68908] General--Difficulties in Understanding Mathematica Syntax
• Date: Wed, 23 Aug 2006 07:15:21 -0400 (EDT)
• Sender: owner-wri-mathgroup at wolfram.com

```Hi Mathematica Experts,

Sorry for a lengthy query.

I am new to Mathematica. The syntax of mathematica is quite different from other programming languages.
I am confused how to use loops like "If",FOR;DO;...

Here i am giving details of a problem i want to solve. I made an attempt to solve this. Please go thru it and give me necessary corrections.

Here i am giving the details:
P = 10.3;l = 0.45mm;T = 0.9;r0 = 0.025mm;d = 0.1643mm;
r[xk_, yk_] := (Sqrt[(x - xk)^2 + (y - yk)^2]);
Intensity[xk_, yk_] := (P/(2*Pi*r[xk, yk]*l))*T^(r[xk, yk] - r0);
Imoy=[Integrate[Intensity[xk, yk]],{xk, 0.1, -0.1}, {yk, 0.1, -0.1}] ;
Print[Imoy]

Then i am getting some value, which is not the correct one.
How to check the output for each step in Mathematica(for example: if i want to find out the values of "r", In C language i can use Printf statement to print the values of "r" for each xk,yk)

And if i want to evaluate the "Intensity[xk_, yk_] " depending on a condition (say: r[xk,yk]<d) [I think it can be done by using IF statement, but i have no clue how to use the IF statement in MATHEMATICA].

It would be better if one can provide me some examples., or documentation which contains some solved examples in Mathematica.