r - How to use the list feature in ffload to selectively load an ffdf? -


how use list feature in ffloadproperly selectively load part of ffdf?

i have read numerous times possible selectively load parts of ff dataframe, can't seem working myself.

my issue i'm trying perform merge vector has list of unique ids ffdf file large computer handle merge.

so far have been trying use ffinfo list of different parts making ffdf.

for instance, following list of "file parts" ffdf in question:

ffinfo(file=paste(imp_tables_root_loc,table_name,sep=""))

where paste(imp_tables_root_loc,table_name,sep="") specifies ffdf table , location

[1] "ffdf1590409e251b.ff" "ffdf159047426082.ff" "ffdf159058a426ab.ff" "ffdf1590410708c.ff"  "ffdf159022b49bf.ff"   [6] "ffdf1590174e5dec.ff" "ffdf159045d93226.ff" "ffdf159037f87280.ff" "ffdf159044ad3d39.ff" "ffdf15905224601a.ff" [11] "ffdf159027936205.ff" "ffdf1590133841c8.ff" "ffdf15902d365cac.ff" "ffdf159065b4259.ff"  "ffdf15904a162908.ff" [16] "ffdf15905529c1c.ff"  "ffdf1590eda1092.ff"  "ffdf1590ab65eb.ff"   "ffdf159048e74f82.ff"

i try ffload calling:

ffload(file=paste(imp_tables_root_loc,table_name,sep=""),list="ffdf1590409e251b.ff")

but results in error:

error in ffload(file = paste(imp_tables_root_loc, table_name, sep = ""), : not in ffarchive: " ffdf1590409e251b.ff",

list: optional vector of names selecting objects restored (default null restores all)

so lets load specific object when ffsave'd multiple. i.e.

r> = as.ffdf(data.frame(x = rnorm(10), y = rbinom(10, 5, .2))) r> b = as.ffdf(data.frame(g = 1:15, h = rpois(15, 5))) r> ffsave(a, b, file = "foo") r> rm(list = ls()) r> ffload("foo", list = "a") r> ls() [1] "a" r> rm(list = ls()) r> ffload("foo", list = "b") r> ls() [1] "b"

i don't think allows load 1 column of ffdf


Comments

Post a Comment

Popular posts from this blog

basic authentication with http post params android -

i doing basic authentication passing username , password , using basicnamevaluepair sending post params response service. my method: public stringbuilder callservicehttppost(string username, string password, string type) { // create new httpclient , post header httpclient httpclient = new defaulthttpclient(); httppost httppost = new httppost(webservice + type); httpresponse response = null; stringbuilder total = new stringbuilder(); try { url url = new url(webservice + type); /*string base64encodedcredentials = base64.encodetostring((username + ":" + password).getbytes(), base64.url_safe | base64.no_wrap);*/ string base64encodedcredentials = "basic " + base64.encodetostring( (username + ":" + password).getbytes(), base64.no_wrap); httppost.setheader("auth...
Read more

vb.net - Virtual Keyboard commands -

i wondering difference between virtual these keyboard commands is: keyeventf_extendedkey , keyeventf_keyup is. everywhere have looked gives me description based off integers , not want know each of them does. you've tagged question vb.net, these have nothing @ vb.net. they're constants defined in windows header files, use win32 api functions. as far difference, can't tell looking @ values. individual values not particularly important, that's why named identifiers used. what's important used , documentation functions tells mean. the first one, keyeventf_extendedkey , used keybdinput structure (which used along e.g. sendinput function) pass information synthesized keyboard input. if flag used, means scan code should interpreted extended key. technically, means scan code preceded prefix byte value 224 (&he0 in hexadecimal notation). the second one, keyeventf_keyup , 1 of flags available use structure. means key being released (going up)...
Read more

css - Firefox for ubuntu renders wrong colors -

Image
i've got following problem: i'm developing website, while testing around i've noticed firefox , chromium display css bar in different colors. when switched between several machine come conclusion firefox ubuntu problem. on other devices i've tested website. it's fine. the differences between chrome , firefox rendering: firefox: chromium: note: firefox ubuntu problem. does knows why , came solution? https://bugzilla.mozilla.org/show_bug.cgi?id=655637 bug 629312 - firefox displays wrong colors on image (only linux) open about:config , rechange gfx.color_management.mode 2 0.
Read more