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    <p>The simplest would be to just manually use symbols <code>cow</code> and <code>monkey</code> rather than strings:</p> <pre><code>In[309]:= cow = 1; monkey = 2; {cow, monkey} Out[311]= {1, 2} </code></pre> <p>But this is probably not what you asked. If you want to automatically convert strings to variables, then what you have to do (if I understood the question correctly) is to first convert your strings to symbols, since symbols can be assigned values and used as variables:</p> <pre><code>Remove[cow,monkey]; str = {"cow", "monkey"}; str1 = ToExpression /@ str {cow, monkey} </code></pre> <p>(I assume that symbols <code>cow</code> and <code>monkey</code> have not been used/defined). After that, you can use the answer for <a href="https://stackoverflow.com/questions/5708142/how-to-set-values-to-symbols/5708395">this</a> question to assign to the variables based on their positions in <code>str1</code>. However, the usefulness of this approach is also questionable.</p> <p>What I think makes the most sense is to create so called <a href="http://reference.wolfram.com/mathematica/tutorial/MakingDefinitionsForIndexedObjects.html" rel="nofollow noreferrer">indexed variables</a>, such as </p> <pre><code>myIndexedVar["cow"] = 1; myIndexedVar["monkey"] = 2; </code></pre> <p>where <code>myIndexedVar</code> is essentially a hash-table of key-value pairs, with keys being your strings and values being whatever you want to assign to them. The process can be automated if needed.</p> <p><strong>EDIT</strong></p> <p>To illustrate assignments to such variables, here is a function which automates that:</p> <pre><code>assignVariables[varNames_List, values_List, hashName_Symbol ] /; Length[varNames] == Length[values] := MapThread[(hashName[#1] = #2) &amp;, {varNames, values}]; </code></pre> <p>Here is how you can use it:</p> <pre><code>In[316]:= assignVariables[str,{{4,2,3},{}},myIndexedVar] Out[316]= {{4,2,3},{}} In[317]:= myIndexedVar["cow"] Out[317]= {4,2,3} In[318]:= myIndexedVar["monkey"] Out[318]= {} </code></pre> <p>But again, this really is a hash-table, so your question makes most sense to me when reformulated as: "I want to make a hash-table with string keys. What's the easiest way to do that in Mathematica, add key-value pairs and access them". The answer seems to be - indexed variables, as illustrated above. You may also find it useful to read on <a href="http://reference.wolfram.com/mathematica/ref/DownValues.html" rel="nofollow noreferrer">DownValues</a>, since these provide the mechanism for indexed variables.</p>
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    1. USLeonid Shifrin
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    1. COYou can also use `Symbol[]` as in `Symbol /@ {"cow", "monkey"}`. I also suggest using indexed variables though. Or possible a replacement list or dispatch table: `values = Dispatch[{"cow" -> {4,2,3},"monkey" -> {}}]` and `"cow" /. values`. This ensures that there won't be any accidental conflict with already existing symbols.
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      1. USSzabolcs
    2. CO@Szabolcs One problem with `Dispatch` is that you can not easily add new key-value pairs once the `Dispatch`-ed rules are formed, without making a new `Dispatch`-ed rules and associated with that performance hit (don't get me wrong - I am a big fan of `Dispatch` :)). Also, I think that indexed variables must be more intuitive to users coming from other languages, who may understand hash tables but who have not seen replacement rules before.
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      1. USLeonid Shifrin
    3. COThis was also in my answer: Your use of `myIndexedVar["cow"]` implies knowledge of the fact that "cow" is in the list. If you know this, why not use the _symbol_ cow instead? If you don't know it's in the list, you can't use the string "cow" as a reference either.
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      1. USSjoerd C. de Vries
 

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