I have answered 1 and 2 by myself, it should be doable with !: verb - foreigns.
Best regards, MG pon., 16 sie 2021 o 22:22 Mariusz Grasko <[email protected]> napisał(a): > Thank you for some ideas on using external parser. > Okay now I have 3 questions: > 1. Is it possible to read CSV file streaming-style (for example record by > record) without loading everything in memory ? Even if I use some external > parsing solution like XSLT or just write something myself in some other > language than J, I will end up with large CSV instead of large XML. It > makes no difference. The reason that I need to parse it like this, is that > there are some rows that I won't need, those would be discarded depending > on their field values. > If it is not possible I would do more work outside of J in this first > parser XML -> CSV. > 2. Is there a way to call external program for J script ? If it is > possible to wait for it to finish ? > If it is not possible, there are definiately ways to run J from other > programs. > 3. Can someone give a little bit of pointer or on how to use api/expat > library ? Do I need to familiarize myself with expat (C library) or just > good understanding of J and reading small test in package directory should > be enough ? > I could send some example file like Devon McCormick suggested. > > Right now I am working through book "J:The natural language for analytic > computing" and playing around with problems like Project Euler, but I could > really see myself using J in serious work. > > Best regards, > MG > > > śr., 11 sie 2021 o 09:51 <[email protected]> napisał(a): > >> In similar situations -but my files are not huge- I extract what I want >> into flattened CSV using one or more XQuery scripts, and then load the CSV >> files with J. The code is clean, compact and easy to maintain. For >> recurrent XQuery patterns, m4 occasionally comes to the rescue. Expect >> minor portability issues when using different XQuery processors >> (extensions, language level...). >> >> >> >> Never got round to SAX parsing beyond tutorials, so I cannot compare. >> >> >> De : Mariusz Grasko <[email protected]> >> À : [email protected] >> Sujet : [Jprogramming] Is is good idea to use J for reading large XML >> files ? >> Date : 10/08/2021 18:05:45 Europe/Paris >> >> Hi, >> >> We are ecommerce company and have a lot of integrations with suppliers, >> products info is nearly always in XML files. I am thinking about using J >> as >> an analysis tool, do you think that working with large files that need to >> be parsed SAX- style without reading everything at once is good idea in J >> ? >> Also is this even advantageous (as in, would code be terse). Right now XML >> parsing is done in Golang, so if parsing in J is not very good we could >> try >> to rely more on CSV exports. CSV is definiately very good in J. >> I am hoping that maybe XML parsing is very good in J and the code would >> become much smaller, if this is the case, then I would think about using J >> for XMLs with new suppliers. >> >> Best Regards >> M.G. >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm >> >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm >> > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
