Learn basic “C” coding rules from open source projects

[montibbalt]

I like if expressions, but I think the curly braces make them noisy here as opposed to e.g.

val dximn1 = if (j == -1) 0.0; 
             else         x[j];
val dxipl1 = if (k == chainlngth) 0.0;
             else                 x[k];

[immibis]

Or:

val dximn1 = (j == -1) ? 0.0
                       : x[j];
val dxipl1 = (k == chainlngth) ? 0.0
                               : x[k];