[R] Executing a script "hand-made" and time

jim holtman jholtman at gmail.com
Thu Jun 30 01:51:33 CEST 2011


What type of computer do you have now: operating system, memory.

Here is how long it took for me to read in a file with 4M lines and 13
columns of numerics on each line:

> system.time(x <- scan('/temp/large.txt', what = 0))
Read 52614432 items
   user  system elapsed
  23.67    0.67   24.39
> str(x)
 num [1:52614432] 1 1 1 1 1 1 1 1 1 1 ...
>
> object.size(x)
420915496 bytes

So how are you reading it in?  Is your system paging?  It should not
take 2 hours.

On Wed, Jun 29, 2011 at 4:43 PM, Trying To learn again
<tryingtolearnagain at gmail.com> wrote:
> Hi all,
>
> I have a function written by me that read a  matrix (data frame) from a txt
> with 4 million of rows and 13 columns.
>
> The think is my function works with an input matrix of 100x13 and now I
> tried to execute my function with the big "input file" and it is running
> form the moment two hours...
>
> There is a way to know (how much time could it cost?)
>
> The second question is...
>
> I want to buy a new computer...to threat files like this (and make on the
> if....for....loops and so on)... I need a computer with high RAM or to
> "speed" this executing time I need other "technical hardware items"....
>
> I´m sure my programmation can be simplied but anyway I hope someone can give
> me his/her opinion.
>
> Many Thaks in advance.
>
>        [[alternative HTML version deleted]]
>
>
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>
>



-- 
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?



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