Re: [Pytables-users] Advice for new user

2012-03-16 Thread Alvaro Tejero Cantero
Thank you for these e-mails with so many useful tips! This is definitely a start. I will report what I find! Cheers, -รก. On Fri, Mar 16, 2012 at 15:00, Francesc Alted wrote: > On Mar 16, 2012, at 1:55 AM, Alvaro Tejero Cantero wrote: > >> Thanks Francesc, we're getting there :). >> >> Some mo

Re: [Pytables-users] Advice for new user

2012-03-16 Thread Anthony Scopatz
Hi Alvaro, I just want to second what Francesc is saying. You do have to get used to the fact that you can't do *everything* that numpy can do inside of PyTables. However, you can do the important stuff which lets you pull out only the data that you are interested in. In fact, PyTables lets you

Re: [Pytables-users] Advice for new user

2012-03-16 Thread Francesc Alted
On Mar 16, 2012, at 1:55 AM, Alvaro Tejero Cantero wrote: > Thanks Francesc, we're getting there :). > > Some more precise questions below. > >> Here it is how you can do that in PyTables: >> >> my_condition = '(col1>0.5) && (col2<24) && (col3 == "novel")' >> mycol4_values = [ r['col4'] for r i

Re: [Pytables-users] Advice for new user

2012-03-15 Thread Alvaro Tejero Cantero
Thanks Francesc, we're getting there :). Some more precise questions below. > Here it is how you can do that in PyTables: > > my_condition = '(col1>0.5) && (col2<24) && (col3 == "novel")' > mycol4_values = [ r['col4'] for r in tbl.where(my_condtion) ] ok, but having data upon which I want to ope

Re: [Pytables-users] Advice for new user

2012-03-15 Thread Francesc Alted
Hola Alvaro, On Mar 15, 2012, at 4:58 PM, Alvaro Tejero Cantero wrote: > Hi Anthony and Francesc, > > please bear with me for one more. > > I was thinking of having this huge array in memory and be able to > write nice indexing expressions, the kind that one writes all the time > with numpy; e.

Re: [Pytables-users] Advice for new user

2012-03-15 Thread Alvaro Tejero Cantero
Hi Anthony and Francesc, please bear with me for one more. I was thinking of having this huge array in memory and be able to write nice indexing expressions, the kind that one writes all the time with numpy; e.g. arr[ fast && novel && checked, 1:4] where fast, novel and checked are boolean arra

Re: [Pytables-users] Advice for new user

2012-03-15 Thread Francesc Alted
On Mar 15, 2012, at 1:43 PM, Anthony Scopatz wrote: > Hello Alvaro > > On Thu, Mar 15, 2012 at 1:20 PM, Alvaro Tejero Cantero > wrote: > Hi! > > Thanks for the prompt answer. Actually I am not clear about switching > from NxM array to N columns (64 in my case). How do I make a > rectangular se

Re: [Pytables-users] Advice for new user

2012-03-15 Thread Anthony Scopatz
Hello Alvaro On Thu, Mar 15, 2012 at 1:20 PM, Alvaro Tejero Cantero wrote: > Hi! > > Thanks for the prompt answer. Actually I am not clear about switching > from NxM array to N columns (64 in my case). How do I make a > rectangular selection with columns? With an NxM array I just have to > do arr

Re: [Pytables-users] Advice for new user

2012-03-15 Thread Alvaro Tejero Cantero
Hi! Thanks for the prompt answer. Actually I am not clear about switching from NxM array to N columns (64 in my case). How do I make a rectangular selection with columns? With an NxM array I just have to do arr[1:2,1:4] to select columns 1,2,3 and time samples 1 to 2.. While it is

Re: [Pytables-users] Advice for new user

2012-03-15 Thread Anthony Scopatz
Hello Alvaro, Thanks for your excitement! On Thu, Mar 15, 2012 at 7:52 AM, Alvaro Tejero Cantero wrote: > Hi everybody! > > I plan to start using PyTables for an application at the University of > Oxford where data is collected in sessions of 2Gb Int16 data organized > as 64 parallel time series

[Pytables-users] Advice for new user

2012-03-15 Thread Alvaro Tejero Cantero
Hi everybody! I plan to start using PyTables for an application at the University of Oxford where data is collected in sessions of 2Gb Int16 data organized as 64 parallel time series (64 detectors), each holding 15 million points (15M). I could handle this sessions separately, but ideally I would