Problems with the variables in VB

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Permalink Reply by David Rutten on September 18, 2013 at 1:16pm

Hi Jose,

you're using Array as a parameter type*, your functions don't have a return type code** and your variables have really awkward names such as n_row, aux_1, iai, iai1, Dp, pDp, b_x, b_y, c, x_rel, x_sol etc. You'll have to clean up your code until the function and variables names are either self-documenting or have documentation comments associated with them. My brain refuses to parse code like this.

* Don't use Array as a function argument unless you absolutely have to. Double() or Int32() is to be preferred.

** Your functions should always include an As clause with return type code.

--

David Rutten

david@mcneel.com

Tirol, Austria

Permalink Reply by Jose M. Ortolano on September 18, 2013 at 2:15pm

Hi David,

thank you for your advices. It is a really awkward code, I know. I just try to prove that the method works and I have a lot of work to do cleaning it. I will try to follow your indications. I am very new on coding, so I expect to improve it.

Thank you again.

Permalink Reply by Jose M. Ortolano on September 19, 2013 at 12:39am

Hi David,

I just realized that I have some problems to deal qith the variables of VB. Can you recommend me a manual to learn the basics? I would really appreciate that. I don´t really understand why it is prefereable not to use Arrays. My program deals with some vectors and matrices and I thought that was the proper way to store the information, but surely I am wrong.

Thank you again for the tips!

Regards.

Permalink Reply by David Rutten on September 19, 2013 at 3:41am

While in RhinoCommon, there are specific types for points and vectors and they are not based on arrays. Matrices often are, and of course you can represent points and vectors as arrays, but it is not a good idea to use the Array type directly. It's not type-safe. Use Double() instead since it specifically represents an Array of Doubles.

Here are my rules for declaring and using variables in VB.NET. Some of them are personal preference, others are widely accepted standards:

• Declare variables as late as possible. Don't put all of them at the top of a function, but rather declare them just before you use them for the first time.
• Declare iteration directly in the loop if possible. I.e. instead of:
    Dim i As Int32
    For i = 0 To N
  Do this:
    For i As Int32 = 0 To N
• Give your variables descriptive names. Sometimes it's ok to use names like i, k, c or r, but by and large it's better to use iteration, kConstant, colour and radius.
• Local and argument variables should be camel cased, starting with a lower case letter. Thus iterationCount and curveOffset rather than Iteration_Count and crvoffset.
• Don't use abbreviations or acronyms like arr, crv, srf when you could just as well use array, curve and surface.
• Declare your variable types as loosely as possible, but no looser. Always keep them type-safe whenever possible. If a function iterates over a list of doubles using the For Each loop, don't ask for an Array, Double(), List<Double>, IList<Double>, ..., but ask for IEnumerable<Double>.
• I prefer to use the m_ prefix for declaring class level variables, but note that this is discouraged in the .NET naming conventions. It's a left-over from hungarian notation that I've stuck with. You're probably better off using pascal casing to differentiate them from method level variables.

There's probably more but I can't think of any right now.

--

David Rutten

david@mcneel.com

Tirol, Austria

Permalink Reply by Benjamin Felbrich on November 27, 2013 at 5:12pm

Hi Jose,

how did your work go further? I am actually trying the same thing as you did. But I wanted to use an already existing library in C# (like alglib). It turns out to be quite tricky to implement these libraries and I hope to be able to do it in time. How long did it take you to get the script working?

Cheers
Benjamin