More than one join and stdin

[aborruso]

Hi I have these 3 CSV

cat join_01.csv
id,name
1,andy
2,anna

cat join_02.csv
id,surname
1,torn
2,montana

cat join_03.csv
id,city
1,Paris
2,London

I would like to join 1 & 2, and then (1 & 2) with 3.

I start with

mlr --csv join -j id -f join_01.csv join_02.csv

But how to join the result of it with 3, without producing an output file?

Is there something like

mlr --csv join -j id -f join_01.csv join_02.csv then join -j id -f /stdin/ join_03.csv

Or something like

mlr --csv join -j id -f join_01.csv join_02.csv | mlr --csv join -j id -f /stdin/ join_03.csv

Or

mlr --csv join -j id -f *.csv

I know that probably the reply is always "no", but I think it would be very useful to have something like these and to have in output something like

id,name,surname,city
1,andy,torn,Paris
2,anna,montana,London

Thank you

[johnkerl]

@aborruso

$ mlr --csv join -j id -f join_01.csv then join -j id -f join_02.csv join_03.csv
id,surname,name,city
1,torn,andy,Paris
2,montana,anna,London

?

[johnkerl]

I'll type this up as an FAQ entry.

[aborruso]

Great, thank you

[aborruso]

I'm reopening it. Then you could close it once the FAQ will be ready

[johnkerl]

http://johnkerl.org/miller-releases/miller-head/doc/cookbook.html#Doing_multiple_joins

Will be in 5.6.0

Thank you! :)

[NikosAlexandris]

I have multiple files with the same structure (== same header), i.e. one of the files looks like:

→ mlr --csv cat input_1.csv
zone,label,mean,stddev
1,Barren,0.985039418507162,0.00327046755267665
2,Permanent Snow and Ice,0.990449367088603,0.00347695390530483
3,Water Bodies,0.989689587426295,0.00283130417558745
9,Urban and Built-up Lands,0.975935137657604,0.00444728462815199
10,Dense Forests,0.982209571011,0.00151525916704626
20,Open Forests,0.982498749692162,0.00156407685057156
25,Forest/Cropland Mosaics,0.983158952435782,0.00119917817740868
30,Natural Herbaceous,0.982886083655933,0.00172176084515656
35,Natural Herbaceous/Croplands Mosaics,0.983636363636364,0.000771389215405308
36,Herbaceous Croplands,0.983256814928586,0.00116699486215588
40,Shrublands,0.977095890410958,0.00439150607284168

I can repeat the above example for up to 3 inputs files:

→ mlr --csv join --ul --ur --lp l --rp r -j zone,label -f input_1.csv then join -j zone,label -f input_2.csv input_3.csv
zone,label,mean,stddev,lmean,lstddev,rmean,rstddev
1,Barren,0.985141452451229,0.00296063409807811,0.985039418507162,0.00327046755267665,0.984987557668154,0.00294390190031405
2,Permanent Snow and Ice,0.990172413793102,0.003303950103698,0.990449367088603,0.00347695390530483,0.989895569620253,0.0036093031143493
3,Water Bodies,0.988460091843363,0.00249696810252014,0.989689587426295,0.00283130417558745,0.988820568927725,0.00259939680954198
9,Urban and Built-up Lands,0.976210534599518,0.00436170313798978,0.975935137657604,0.00444728462815199,0.976246019422661,0.00448461857275749
10,Dense Forests,0.982076308739861,0.00148154340071296,0.982209571011,0.00151525916704626,0.982190048828062,0.00146571376545496
20,Open Forests,0.982497740034809,0.00153034810204273,0.982498749692162,0.00156407685057156,0.982466195761245,0.00150786476199308
25,Forest/Cropland Mosaics,0.983225779156313,0.00117294632959691,0.983158952435782,0.00119917817740868,0.983067448680308,0.00118920277246029
30,Natural Herbaceous,0.982983720528064,0.00166879860717559,0.982886083655933,0.00172176084515656,0.982925841727431,0.00165974257213183
35,Natural Herbaceous/Croplands Mosaics,0.983354838709678,0.00106402725807591,0.983636363636364,0.000771389215405308,0.983575757575758,0.000817620458171498
36,Herbaceous Croplands,0.983352463549144,0.00113906386917183,0.983256814928586,0.00116699486215588,0.983220069731363,0.00116521692353466
40,Shrublands,0.977145547945205,0.00442587899140026,0.977095890410958,0.00439150607284168,0.977166380789022,0.00444267104546084

How about doing this for many more input files?

[johnkerl]

Hi @NikosAlexandris I split this out as #403