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It's old question. However, I could not find satisfactory answer. Decided to post this question. I have a .csv file with column heading. How can I import this .csv file into Mathematica assigning column names as list names in short and sweet way. For example, I can use the following codes.

mydata = Import[file, Path -> path];
names = Flatten[mydata[[;; 1]]]; 
Do[listnames[names[[i]]] = 
                     mydata[[2 ;;]][[All, i]], {i, 1, Dimensions[mydata[[2 ;;]]][[2]]}];

But I need to write listnames["Col names in .csv file"] to refer to each list. I can not refer .csv column names as list names. I need to figure out this because I have over 1000 column headings in my .csv data. Please help me to figure out his without long codes.

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1 Answer 1

Reset to default
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Update

Inspired by Andy Ross

header = First @ iris;

header = StringReplace[header,"."->""](Because Dot is protected in Mathematica)

data = Rest @ iris;

assign[name_, value_] := Evaluate[ToExpression[name]] = value;

Thread[ assign[header, Transpose@data] ]

====================================================================

If you are using Mathematica 10, there is a new data type called Dataset. Take the iris data for example. Suppose the iris.csv is in d:\.

iris = Import["d:/iris.csv","CSV"];

header = iris[[1]];

data = iris[[2;;]];

irisDataset = Thread[header -> #]& /@ data // Map[Association] // Dataset

and it will display like this:

enter image description here

Please refer to Dataset reference for more information.

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  • $\begingroup$ Thank you for your time. Yes, I am using Mathematica 10. I tried your codes but it does not give me the results I desire. I want the column names of .csv file as list names so that I can refer each .csv column data by their column name as list name in Mathematica. In your example, I should be able to refer each column as a separate list with its name being column heading. I should be able to refer first column as a list as Sepal.Length, second column as another list as Sepal.Width and so on.... $\endgroup$
    – ramesh
    Commented Aug 12, 2014 at 0:54
  • $\begingroup$ @rkadhikari I advise reading the documentation page for Dataset -- it's pretty trivial to take a dataset and extract the raw columns from it, but you might find the Dataset itself much easier to work with for some kinds of things. $\endgroup$
    – Taliesin Beynon
    Commented Aug 12, 2014 at 2:33
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    $\begingroup$ @PhilChang SemanticImport makes it really easy to import a tabular file as a Dataset if they have a reasonable structure -- no need to parse it to and format it yourself. So for example your code could just be replaced with SemanticImport["https://raw.githubusercontent.com/pydata/pandas/master/pandas/tests/data/iris.csv"] $\endgroup$
    – Taliesin Beynon
    Commented Aug 12, 2014 at 2:36
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    $\begingroup$ An alternative way to create a Dataset is irisDataset = Dataset[Inner[Rule, header, Transpose[data], Association]]. $\endgroup$
    – Ernst Stelzer
    Commented Aug 12, 2014 at 7:38
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    $\begingroup$ @PhilChang You can achieve the same result as in your answer with just Import with the Dataset representation and the HeaderLines option: Import["d:/iris.csv", {"CSV", "Dataset"}, "HeaderLines" -> 1] $\endgroup$
    – barrywardell
    Commented Nov 24, 2017 at 0:42

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