Re: Export with append??

*To*: mathgroup at smc.vnet.net*Subject*: [mg129494] Re: Export with append??*From*: Szabolcs HorvÃt <szhorvat at gmail.com>*Date*: Fri, 18 Jan 2013 00:51:13 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net*References*: <kd5hu2$jjp$1@smc.vnet.net> <20130117041653.995FF6882@smc.vnet.net>

As I understood, this is what the OP was asking for. It will work with any export format, but of course it is true that with some formats it doesn't make sense. Appending two PDFs will just breaks them. With some formats, e.g. CSV, it can be useful. On 17 January 2013 10:14, Murray Eisenberg <murray at math.umass.edu> wrote: > But surely appending like that won't work for many export formats. E.g., I > hesitate to think what it might do to a PDF export. > > On Jan 16, 2013, at 11:16 PM, Szabolcs <szhorvat at gmail.com> wrote: > > > Hello Maarten, > > > > In fact there is a simple way to make Export append rather than > overwrite. Please see here: > > > > http://mathematica.stackexchange.com/a/2228/12 > > > > You just need to use a stream in place of the file name: > > > > file = OpenAppend["out.txt"] > > > > Export[file, data, "CSV"]; > > WriteString[file, "\n"]; > > > > Close[file] > > > > On Wednesday, 16 January 2013 01:38:58 UTC-5, Maarten van der Burgt > wrote: > >> Dear Alexei, > >> > >> > >> > >> Thanks for your help. Hope the Wolfram folks are reading this as well. > >> > >> Something simple like this should really be an option in the function > >> > >> Export. > >> > >> > >> > >> Meanwhile I found back something similar for XLS files in my knowledge > >> > >> base: > >> > >> > >> > >> XLAppend[oldfile_, newfile_, newdata_] := Module[ > >> > >> > >> > >> {sheets, olddata, completedata}, > >> > >> > >> > >> sheets = Import[oldfile, "Sheets"]; > >> > >> > >> > >> olddata = {#, Import[oldfile, {"Sheets", #}]} & /@ sheets; > >> > >> > >> > >> completedata = Join[olddata, newdata]; > >> > >> > >> > >> Export[newfile, Rule @@@ completedata] > >> > >> > >> > >> ] > >> > >> > >> > >> > >> > >> > >> > >> Best regards, > >> > >> > >> > >> > >> > >> > >> > >> Maarten > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> Maarten van der Burgt > >> > >> > >> > >> Product Engineering - ICOS Division > >> > >> > >> > >> ________________________________ > >> > >> > >> > >> KLA-Tencor | ICOS Division > >> > >> Tel: +32 16 398220 | Direct: +32 16 398263 | Fax: +32 16 400067 > >> > >> > >> > >> KLA-TENCOR (Belgium) - Haasrode Research Park 1112 - Esperantolaan 8 - > >> > >> B-3001 Leuven - BELGIUM > >> > >> > >> > >> Mail: maarten.vanderburgt at kla-tencor.com > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> From: Alexei Boulbitch [mailto:Alexei.Boulbitch at iee.lu] > >> > >> Sent: maandag 14 januari 2013 10:22 > >> > >> Cc: Maarten van der Burgt > >> > >> Subject: Re: Export with append?? > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> Hallo, > >> > >> > >> > >> > >> > >> > >> > >> With a command like > >> > >> > >> > >> > >> > >> > >> > >> Export["myfile.dat", results, "List" ] > >> > >> > >> > >> > >> > >> > >> > >> is there a way to append the results to an existing myfile.dat, rather > >> > >> > >> > >> than creating or overwriting an existing file? > >> > >> > >> > >> > >> > >> > >> > >> thanks for your help, > >> > >> > >> > >> > >> > >> > >> > >> Maarten > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> Hi, Maarten, > >> > >> > >> > >> A simple workaround is to import your file, append a new file to it and > >> > >> then - to export the combined list. Assume that your mathematica > >> > >> notebook entitled "trialImportExport.nb" is situated in the same folder > >> > >> as the already existing list entitled "myfile.dat". > >> > >> > >> > >> To be precise I generated the file myfile.dat with the list: > >> > >> > >> > >> {25, 36, 49} > >> > >> > >> > >> in it. Assume further that I want to append the list > >> > >> > >> > >> {a,b,c} > >> > >> > >> > >> to it. Then the code > >> > >> > >> > >> > >> > >> > >> > >> lst1=Import[NotebookDirectory[]<>"myfile.dat"]//Flatten; > >> > >> > >> > >> lst2={a,b,c}; > >> > >> > >> > >> lst3=Append[lst1,lst2]//Flatten; > >> > >> > >> > >> Export[NotebookDirectory[]<>"myfileNew.dat",lst3] > >> > >> > >> > >> > >> > >> > >> > >> Does the job. The output cell below: > >> > >> > >> > >> > >> > >> > >> > >> D:\Documents and Settings\ABo\My > >> > >> Documents\Works\Mathematica_works\Examples\TrialFiles\myfileNew.dat > >> > >> > >> > >> > >> > >> > >> > >> shows that the file has been successfully exported. > >> > >> > >> > >> I intentionally gave the resulting file a new name, "myfileNew.dat", to > >> > >> check the result, but the old name can also be given to it. > >> > >> > >> > >> > >> > >> > >> > >> Have fun, Alexei > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> Alexei BOULBITCH, Dr., habil. > >> > >> > >> > >> IEE S.A. > >> > >> > >> > >> ZAE Weiergewan, > >> > >> > >> > >> 11, rue Edmond Reuter, > >> > >> > >> > >> L-5326 Contern, LUXEMBOURG > >> > >> > >> > >> > >> > >> > >> > >> Office phone : +352-2454-2566 > >> > >> > >> > >> Office fax: +352-2454-3566 > >> > >> > >> > >> mobile phone: +49 151 52 40 66 44 > >> > >> > >> > >> > >> > >> > >> > >> e-mail: alexei.boulbitch at iee.lu > > --- > Murray Eisenberg murray at math.umass.edu > Mathematics & Statistics Dept. > Lederle Graduate Research Tower phone 413 549-1020 (H) > University of Massachusetts 413 545-2838 (W) > 710 North Pleasant Street fax 413 545-1801 > Amherst, MA 01003-9305 > > > > > >

**References**:**Re: Export with append??***From:*Szabolcs <szhorvat@gmail.com>