How to delete and keep some columns for a txt file in R? -



How to delete and keep some columns for a txt file in R? -

i have file in txt format , delimited tabs, here extract:

id 1 2 4 15 18 20 1_at 100 200 89 189 299 788 2_at 8 78 33 89 90 99 3_xt 300 45 53 234 89 34 4_dx 49 34 88 8 9 15

now have file, in txt format, , separated commas next data:

18,1,4,20

so based on file, read , extract columns first tabulated info can store in file this:

(important: need maintain order of info stored according csv file)

id 18 1 4 20 1_at 299 100 89 788 2_at 90 8 33 99 3_xt 89 300 53 34 4_dx 9 49 88 15

if info want extract rows easier because read row row , comparing txt file (i have done that), stuck column stuff.

i wonder if there way extract straight columns using subindex function?

any help appreciated.

this 1 way of doing want if don't want read whole file , filter. way work if don't know classes of each column before hand. this illustration assumes input file has column names not starting digits not allowed in r. work digits column name well, cautious may fail in other operations.

> txt = 'id 1 2 4 15 18 20 + 1_at 100 200 89 189 299 788 + 2_at 8 78 33 89 90 99 + 3_xt 300 45 53 234 89 34 + 4_dx 49 34 88 8 9 15' > > df <- read.table(textconnection(txt), header=t, nrows=1, check.names=f) > > df id 1 2 4 15 18 20 1 1_at 100 200 89 189 299 788 > > #lets f column filter read other file > f <- c("id", "18", "1", "4", "20") > > f [1] "id" "18" "1" "4" "20" > > #get column classes > cc <- sapply(df, class) > cc id 1 2 4 15 18 20 "factor" "integer" "integer" "integer" "integer" "integer" "integer" > #specify columns don't want read "null" > cc[!names(cc) %in% f] <- "null" > cc id 1 2 4 15 18 20 "factor" "integer" "null" "integer" "null" "integer" "integer" > > #read whole info frame 1 time again > df <- read.table(textconnection(txt), header=t, colclasses=cc, check.names=f) > > #get columns in desired order > df[,f] id 18 1 4 20 1 1_at 299 100 89 788 2 2_at 90 8 33 99 3 3_xt 89 300 53 34 4 4_dx 9 49 88 15

r file calculated-columns

Comments

Post a Comment

Popular posts from this blog

web services - java.lang.NoClassDefFoundError: Could not initialize class net.sf.cglib.proxy.Enhancer -

web services - java.lang.NoClassDefFoundError: Could not initialize class net.sf.cglib.proxy.Enhancer - when trying request rest service @ time of response getting exception.. feb 21, 2013 2:34:49 pm com.sun.jersey.spi.container.containerresponse mapmappablecontainerexception severe: exception contained within mappablecontainerexception not mapped response, re-throwing http container java.lang.noclassdeffounderror: not initialize class net.sf.cglib.proxy.enhancer @ org.hibernate.proxy.pojo.cglib.cgliblazyinitializer.getproxyfactory(cgliblazyinitializer.java:117) @ org.hibernate.proxy.pojo.cglib.cglibproxyfactory.postinstantiate(cglibproxyfactory.java:43) @ org.hibernate.tuple.entity.pojoentitytuplizer.buildproxyfactory(pojoentitytuplizer.java:162) @ org.hibernate.tuple.entity.abstractentitytuplizer.<init>(abstractentitytuplizer.java:135) @ org.hibernate.tuple.entity.pojoentitytuplizer.<init>(pojoentitytuplizer.java:55) @ org.hibernate.tuple.e...
Read more

Accessing MATLAB's unicode strings from C -

Accessing MATLAB's unicode strings from C - how can access underlying unicode info of matlab strings through matlab engine or mex c interfaces? here's example. let's set unicode characters in utf-8 encoded file test.txt, read as fid=fopen('test.txt','r','l','utf-8'); s=fscanf(fid, '%s') in matlab. now if first feature('defaultcharacterset', 'utf-8') , c engevalstring(ep, "s") , output text file utf-8. proves matlab stores unicode internally. if mxarraytostring(enggetvariable(ep, "s")) , unicode2native(s, 'latin-1') give me in matlab: non-latin-1 characters replaced character code 26. need getting access underlying unicode info c string in unicode format (utf-8, utf-16, etc.), , preserving non-latin-1 characters. is possible? my platform os x, matlab r2012b. addendum: documentation explicitly states "[mxarraytostring()] supports multibyte encoded characters...
Read more

javascript - mongodb won't find my schema method in nested container -

javascript - mongodb won't find my schema method in nested container - i trying access method of schema stored within mixed container. here situation : have cases model can many different things, have schema each of these things stored in "casecontent" mixed property. var caseschema = mongoose.schema({ casecontent : {}, object : {type:string, default : "null"}, collision : {type : boolean, default : false} }); the casecontent property filled model of 1 of schemas, 1 exemple : var treeschema = new mongoose.schema({ applecount : {type : number, default : 3} }); treeschema.methods.dostuff = function (data) { console.log('hey, listen'); homecoming true; }; then, want utilize method of schema original container : caseschema.methods.dostuff = function (data) { if (this.casecontent.dostuff !== undefined) { this.casecontent.dostuff(); console.log('it worked'); } else { ...
Read more