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Possible Duplicate:
How do I use Map for a function with two arguments?

If I have a function:

F[x_,y_,z_]:=x*y*z

and I want to call it with several different x values using Map (and y and z fixed), is there a way to do that with a one-liner?

That is, for these x values

xVals = {1,2,3,4}

I want to somehow get:

{F[1,10,100], F[2,10,100], F[3,10,100],F[4,10,100]}

If I can do it with Map, it would be great, because I have many cores and want to speed this up with the parallelized Map.

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    $\begingroup$ You may use map with a pure function, f[#,10,100]&/@ xvals. (I renamed your function to lowercase to keep with conventions.) $\endgroup$ Commented Oct 9, 2012 at 19:56
  • $\begingroup$ +1 Thanks! Is there a way to do it in a grid (i.e. vary xvals and yvals)? $\endgroup$ Commented Oct 9, 2012 at 19:58
  • $\begingroup$ I want to essentially do a nested for loop to return a nested list: { forall yvals {forall xvals f[xval, yval,100]} } $\endgroup$ Commented Oct 9, 2012 at 20:02
  • $\begingroup$ I'm fairly certain this is a duplicate but I cannot find it. Anyone? $\endgroup$ Commented Oct 9, 2012 at 20:26
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    $\begingroup$ @Mr.Wizard yes, in this case. Don't delete, though: the answers are good $\endgroup$ Commented Oct 9, 2012 at 21:40

3 Answers 3

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You may use map with a pure function:

f[#,10,100]& /@ xVals 
{f[1, 10, 100], f[2, 10, 100], f[3, 10, 100], f[4, 10, 100]}

Table will also work:

Table[f[x, 10, 100], {x, xVals}] 
{f[1, 10, 100], f[2, 10, 100], f[3, 10, 100], f[4, 10, 100]}

Multiple iterator form:

Table[f[x, y, 100], {x, {1, 2, 3, 4}}, {y, {5, 6, 7, 8}}]
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  • $\begingroup$ +1 I can also use parallel table to get an 8x speedup! $\endgroup$ Commented Oct 9, 2012 at 20:30
  • $\begingroup$ Thanks, Mr. Wizard, for the edits. $\endgroup$ Commented Oct 9, 2012 at 22:04
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F[x_, y_, z_] := x*y*z; xVals = {1, 2, 3, 4}; yVals = {5, 6, 7, 8};

You could use thread for this:

Thread[d[xVals, yVals, 100]] (* yields *) {d[1, 5, 100], d[2, 6, 100], d[3, 7, 100], d[4, 8, 100]}
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    $\begingroup$ Does not work well with tensors, but MapThread does! $\endgroup$ Commented Mar 4, 2018 at 2:43
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You can use Outer to get a nested output list :

Outer[f[#1, #2, 100] &, {1, 2, 3, 4}, {5, 6, 7, 8}] (* {{500, 600, 700, 800}, {1000, 1200, 1400, 1600}, {1500, 1800, 2100, 2400}, {2000, 2400, 2800, 3200}} *)

However I'm not sure you can take advantage of Parallelize.

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