Tagged Questions

Questions about the Text based file format CSV (Comma Seperated Values). Questions include, but are not restricted to, importing from and exporting to this file format.

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1
vote
0answers
30 views

Import csv file and missing “” when importing [closed]

I am importing a csv file. When it imports and shows the import there are no quotes around the alpha characters or the date. Like this: {32856, 1, A, 10/1/2001, 1, 1, -54.4, , 4, 1, 1, 1, , , , \ ...
3
votes
1answer
97 views

Efficiently reading CSV with ReadList

I have a large CSV file (~1gb) with mixed data. Basically with strings and integers. It takes very long to import this whole dataset with Import[] so I would like ...
1
vote
3answers
142 views

How to import files with headers?

R has excellent header supports such as read.table with header options. I don't want to mess up with text-processing or stream-processing. I am looking for a similar tool as in R because it saves a ...
1
vote
0answers
34 views

Exposing .csv via Wolfram Cloud API

I'm sure there's a better way to accomplish this, but my goal is to generate a .csv file from a running notebook, and have it accessible by API. In the main program, I'm exporting the data like so: ...
1
vote
2answers
65 views

How do you (sanely) fix up data in a csv/table?

I have data in a CSV file I've Import[]ed. Some of the data needs fixing up - date formats changed, data normalized, etc. After fixing up I'll insert it into an SQL database. My CSV file has ...
6
votes
1answer
172 views

Incorrect result while using SemanticImport for CSV file import

I might use this incorrectly. I want to use a .csv file that (as list) looks like: ...
3
votes
2answers
238 views

Why does a certain CSV file import properly into LibreOffice but not into Mathematica 10.0?

I'm working on a project involving data manipulation and it involves working with CSV files. I know that the files are properly formatted as when I import them into LibreOffice, all of the columns ...
3
votes
1answer
406 views

Reading csv/xlsx data into Mathematica with column headings as list names

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 ...
11
votes
2answers
475 views

Parsing a CSV file using Interpreter

The new Interpreter functionality in version 10 looks like it has the potential to make parsing custom data formats very easy. I'm trying to create a CSV parser. ...
7
votes
2answers
184 views

Export a simple DataSet with key-value associations to CSV in Mathematica 10

I'm trying to Export a simple dataset with key-value pairs to a CSV Export["n.csv", MyDataset, "CSV"] This results in a single-line serialization: ...
1
vote
1answer
96 views

ListPlot[] code for CSV file not working

I have a CSV file with $9$ columns. I want to plot them in the following way. Column $1$ will be along the $X$-axis. Any point $(x_i, y_i)$ of $i$-th curve in the plot will have the $x$ value from the ...
6
votes
1answer
138 views

Reading specific entries from a CSV file

This question is related to the following: Speeding up Import and Export in CSV format Stream CSV files Reading periodic elements from a large file I have a set of very large CSV files (a few ...
1
vote
1answer
137 views

Import CSV with “Numeric”->True and “DateStringFormat” problem

The CSV file linked below has 3 columns: "PT_ID" (char 4), "PHYS_ID" (char 2) and "VISIT_START_TIME" (varchar eg "0:00:15" hours minutes seconds) ...
2
votes
1answer
106 views

Export CSV from tables

I am reading my csv which looks like: float,float,float,integer,boolean I read it with: ...
0
votes
0answers
140 views

Savitzky-golay filter

How to use Savitzky-golay filter on csv file? I have file.csv in this format: 0.1,1.6,2.8,0 0.2,1.2,2.3,1 0.7,1.5,2.4,2 0.6,1.2,2.7,3 0.4,1.4,2.9,4 0.3,1.3,2.5,5 ...
4
votes
2answers
224 views

Exporting strings without the quotes

I'm trying to export the following string "sep = ," to a CSV-file, as to be able to define the separation symbol. However, when using the following command: ...
8
votes
2answers
1k views

Speeding up Import and Export in CSV format

I am handling large numerical data in Mathematica. In smaller problems everything worked fine using Export and Import with the ...
1
vote
1answer
194 views

Export list as a .csv file, but not seeing the commas

My goal is to export a list of numbers into a file, with a comma between each value. Executing the following commands seems to produce a file with a new line between each entry. ...
2
votes
1answer
174 views

Writing CSV or alternative

I've tried to export a list to a CSV file. I shut it down after about 20 minutes of processing. The list has 261,000 rows and 30 columns. I finally exported it to a txt file and its size was 111 ...
4
votes
2answers
277 views

Can Mathematica understand Excel dates when in number format?

I have a very large Excel file with dates in the format 2013/01/17 08:02:00 PM which is a custom date format. I have to convert this file to CSV in order to import it into Mathematica because I can't ...
3
votes
1answer
699 views

How do I read a CSV file and remove comments from it

I have very recently started using Mathematica 9.0 Home Edition and am trying to understand it as best I can so please be tolerant ;). I have a file of data (sugar.csv) which contains blood sugar ...
0
votes
1answer
221 views

Mathematica: how to make Z transformation of data from CSV File

I have a discrete Signal in my CSV File and I want to transform it in Z. I import the data with Data=Import["T:/data.csv","CSV"] and I try to transform it ...
2
votes
1answer
682 views

How to export CSV from Mathematica?

I have previously been using logf[x_, y_] := f[x, y] /. v_ :>(PutAppend[Unevaluated[f[x, y] = v;], "out.txt"];); which produces output like ...
11
votes
4answers
1k views

Import[ ] drops leading zeros from data when importing a CSV file

I need to load data from the CSV file shown below. Import[ ] drops the leading zeros in column 3 when it imports the CSV file, but they are security identifiers, and I need them. ReadList[ ] ...
2
votes
2answers
779 views

Interpreting the interpolating function and saving data to plot with external program

So far I have been solving non-linear pdes with NDSolve and then plotting the result with the in-built Plot3D and ...
0
votes
2answers
569 views

How can I plot Intensity values(Z) based on X and Y position. Data stored as 3 columns in CSV file

I have a CSV data file with X position, Y position and corresponding intensity as Z. I ...
4
votes
2answers
2k views

Plot CSV-data; make statistical statements in Mathematica / WA

First, I'm quite new to Mathematica so sorry in advance if some questions seem to be trivial. I have a CSV-file which looks like this: ...
6
votes
1answer
691 views

Stream CSV files

Ram limitations make import impractical for large CSV files. Is it possible to Stream CSV correctly? ...