add C implementation to @stdlib/math/base/special/ldexp

[Pranavchiku]

Resolves #638

Checklist

• update readme.md
• include.gypi
• binding.gyp
• include/stdlib/math/base/special/
• src
• manifest.json
• lib
• examples
• benchmark
• test

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@kgryte

[Pranavchiku]

I am not much confident about the implementation of addon.c if you can check that would be of great help.

[kgryte]

@Pranavchiku You need to refactor the addon.c file to handle two input arguments, not just one.

[Pranavchiku]

@Pranavchiku You need to refactor the addon.c file to handle two input arguments, not just one.

I was thinking to wrap the frac and exp in <Float64Array>[frac, exp] and then pass it as a single argument.
Or should I go with passing 2 arguments separately?

[kgryte]

Pass both separately. No need to pass as a separate array. We only pass arrays for base functions operating on numbers when we have multiple output arguments.

[Pranavchiku]

I guess, we returned to original place !

The frexp updates were merged a couple of days ago (#651), so no need to merge from your local frexp2 branch.

It shows me lots of conflicts in different files, hence I chose to merge the existing frexp2 branch, but I didn't pull latest changes from upstream hence it had conflicts.

[kgryte]

The examples still need to be updated, but I can do this on my end.