Using MapReduce with german CSV format

1 次查看（过去 30 天）
Thomas
Thomas 2015-12-11
评论： Thomas 2015-12-11
I try to use the MapReduce function to handel CSV files. My cells are seperated with ";" and are written in german format. e.g. header and 3 meassurements "k;temperature 0;20,4 1;20,8 2;21,1" not the englisch format "k,temperature 0,20.4 1,20.8 2,21.1" I found the option to use a ";" insted a "," for cell seperating by using mapreduce. But how to change the "." into "," for the numbers? I use Matlab 2015b. Thanks, TF

请先登录，再回答此问题。

采纳的回答

Kirby Fears
Kirby Fears 2015-12-11

更多回答（1 个）

Thomas
Thomas 2015-12-11
Thank you for the answer. Now I can read the numerical data as a string and convert it to a number. It works well for small amount of data. But I work with huge amount of Data (some GB „Big Data“). I compare it for a 25MB file. The computation time for a file with conversion (string too number) is 65 seconds and for a file without conversion (string to number) it is 1.5 seconds. Is there no other way to read my data directly as numbers? Thanks, TF
  2 个评论
Kirby Fears
Kirby Fears 2015-12-11
Are you first setting up your input with the datastore() command?
http://www.mathworks.com/help/matlab/ref/datastore.html
Unfortunately datastore properties do not allow you to set the decimal character.
Thomas
Thomas 2015-12-11
Yes. I use datastore to read my data. Thanks for help.
So it has to be a task for Mathworks to add these option.

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 MapReduce 的更多信息

标签

产品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by