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POCan someone explain what the ternary operator is doing in this code?
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copied!<p>I found this example C code from <a href="http://mitpress.mit.edu/books/audio-programming-book" rel="nofollow">"The Audio Programming Book"</a>.</p> <p>I understand basically what the code is doing. It takes an array of values that represent the amplitude of series of sine waves and adds them together to create a complex wave.</p> <p>I am OK with everything except the line with reads:</p> <pre><code>a = amps ? amps[i] : 1.f; </code></pre> <p>I know Ternary Operators are basically If/Else statement, but I cannot seem to figure out what this is doing exactly, because 'amps' is not defined earlier in the code. It doesn't make sense that amps is reusing amps[], it seem that would be a no no. I also haven't been able to find an example anywhere that matches up with this anywhere else.</p> <p>But the code compiles, so I am completely baffled by what is it NOT wrong, and just what it is doing exactly.</p> <p>If someone can explain what this is doing [is a traditional If/Else form] I would greatly appreciate it. </p> <pre><code>float* TableGEN::fourier_table(int harms, float *amps, int length, float phase) { float a; float *table = new float[length+2]; double w; phase *= (float)pi*2; memset(table, 0, (length+2)*sizeof(float) ); for(int i=0; i < harms; i++) for(int n=0; n < length+2; n++) { a = amps ? amps[i] : 1.f; w = (i+1)*(n*2*pi/length); table[n] += (float) (a*cos(w+phase)); } normalise_table(table, length , 1.0f ); return table; } </code></pre> <p>Thanks</p> <p>Stan</p>

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