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<div>Apologies if this is a naive question - I'm a beginner with Rcpp. I did see some earlier discussion on similar topic, but I don't think it answered my questions. </div>
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<div>I am trying (on Windows) to speed up a function currently written in R. This works very well for real-valued arguments of the function. But it needs to work for complex arguments as well. Here is a stripped down (but still non-working) example of what I
am trying to do <br>
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<div>cppFunction('</div>
<div> ComplexVector test(ComplexVector s, ComplexVector lambda) {</div>
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<div> int n = s.size();<br>
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<div> int m = lambda.size();</div>
<div> ComplexVector out(n);<br>
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<div> for (int i=0; i < n; ++i) {<br>
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<div> for (int j=0; j < m; ++j) {<br>
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out[i] = out[i] - log(s[i] + 1/lambda[j]) / 2; </div>
<div><span style="font-size: 12pt;"> }</span><br>
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<div> }<br>
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<div> return out;</div>
<div> }<br>
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<div>')</div>
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<div><span style="font-size: 12pt;">I have (at least) 2 problems</span><br>
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<div>i) Are the logarithm and exponential functions implemented for complex arguments? If not is there a work-around?<br>
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<div>ii) What is the best way to specify constants like 1 and 2 as complex constants? This must be easy, but everything I tried so far gives an error (except passing them into the function via an extra ComplexVector argument, but there must be a better way). </div>
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<div>Many thanks for any help,</div>
<div>Martin Ridout<br>
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