diff --git a/doc/content-for-cookbook.html b/doc/content-for-cookbook.html
index c0adbda49..85962db0c 100644
--- a/doc/content-for-cookbook.html
+++ b/doc/content-for-cookbook.html
@@ -49,8 +49,33 @@ POKI_RUN_COMMAND{{mlr --csv --irs lf --opprint rename -r -g ' ,_' data/spaces.c
You can also do this with a for-loop but it puts the modified fields after the unmodified fields:
+POKI_RUN_COMMAND{{cat data/bulk-rename-for-loop.mlr}}HERE
+
POKI_RUN_COMMAND{{mlr --icsv --irs lf --opprint put -f data/bulk-rename-for-loop.mlr data/spaces.csv}}HERE
+Headerless CSV on input or output
+
+Sometimes we get CSV files which lack a header. For example:
+
+POKI_RUN_COMMAND{{cat data/headerless.csv}}HERE
+
+ You can use Miller to add a header: the --implicit-csv-header applies positionally indexed labels:
+
+POKI_RUN_COMMAND{{mlr --csv --rs lf --implicit-csv-header cat data/headerless.csv}}HERE
+POKI_RUN_COMMAND{{mlr --icsv --irs lf --implicit-csv-header --opprint cat data/headerless.csv}}HERE
+
+ Following that, you can rename the positionally indexed labels to names with meaning for your context.
+For example:
+
+POKI_RUN_COMMAND{{mlr --csv --rs lf --implicit-csv-header label name,age,status data/headerless.csv}}HERE
+POKI_RUN_COMMAND{{mlr --icsv --rs lf --implicit-csv-header --opprint label name,age,status data/headerless.csv}}HERE
+
+ Likewise, if you need to produce CSV which is lacking its header, you can pipe Miller’s output
+to the system command sed 1d, or you can use Miller’s --headerless-csv-output option:
+
+POKI_RUN_COMMAND{{head -5 data/colored-shapes.dkvp | mlr --ocsv cat}}HERE
+POKI_RUN_COMMAND{{head -5 data/colored-shapes.dkvp | mlr --ocsv --headerless-csv-output cat}}HERE
+
Regularizing ragged CSV
Miller handles compliant CSV: in particular, it’s an error if the
@@ -65,8 +90,6 @@ POKI_INCLUDE_AND_RUN_ESCAPED(data/ragged-csv.sh)HERE
or, more simply,
-POKI_RUN_COMMAND{{cat data/small}}HERE
-
POKI_INCLUDE_AND_RUN_ESCAPED(data/ragged-csv-2.sh)HERE
Two-pass algorithms
@@ -77,7 +100,8 @@ allowing many of its verbs to process files that are (much) larger than the
amount of RAM present in your system. (Of course, Miller verbs such as
sort, tac, etc. all must ingest and retain all input records
before emitting any output records.) You can also use out-of-stream variables
-to perform multi-pass computations.
+to perform multi-pass computations, at the price of retaining all input records
+in memory.
Two-pass algorithms: computation of percentages
diff --git a/doc/cookbook.html b/doc/cookbook.html
index 1c83b2ef5..aa2c180f4 100644
--- a/doc/cookbook.html
+++ b/doc/cookbook.html
@@ -142,6 +142,7 @@ Miller commands were run with pretty-print-tabular output format.
• Parsing log-file output
• Rectangularizing data
• Bulk rename of field names
+• Headerless CSV on input or output
• Regularizing ragged CSV
• Two-pass algorithms
• Two-pass algorithms: computation of percentages
@@ -329,6 +330,21 @@ a_b_c def g_h_i
You can also do this with a for-loop but it puts the modified fields after the unmodified fields:
+
+
+
+$ cat data/bulk-rename-for-loop.mlr
+for (oldk,v in $*) {
+ @newk = gsub(oldk, " ", "_");
+ if (@newk != oldk) {
+ unset $[oldk];
+ $[@newk] = v
+ }
+}
+
+
@@ -341,6 +357,106 @@ def a_b_c g_h_i
+Headerless CSV on input or output
+
+Sometimes we get CSV files which lack a header. For example:
+
+
+
+
+$ cat data/headerless.csv
+John,23,present
+Fred,34,present
+Alice,56,missing
+Carol,45,present
+
+
+
+$ mlr --csv --rs lf --implicit-csv-header cat data/headerless.csv
+1,2,3
+John,23,present
+Fred,34,present
+Alice,56,missing
+Carol,45,present
+
+
+
+$ mlr --icsv --irs lf --implicit-csv-header --opprint cat data/headerless.csv
+1 2 3
+John 23 present
+Fred 34 present
+Alice 56 missing
+Carol 45 present
+
+
+
+$ mlr --csv --rs lf --implicit-csv-header label name,age,status data/headerless.csv
+name,age,status
+John,23,present
+Fred,34,present
+Alice,56,missing
+Carol,45,present
+
+
+
+$ mlr --icsv --rs lf --implicit-csv-header --opprint label name,age,status data/headerless.csv
+name age status
+John 23 present
+Fred 34 present
+Alice 56 missing
+Carol 45 present
+
+
+
+$ head -5 data/colored-shapes.dkvp | mlr --ocsv cat
+color,shape,flag,i,u,v,w,x
+yellow,triangle,1,11,0.6321695890307647,0.9887207810889004,0.4364983936735774,5.7981881667050565
+red,square,1,15,0.21966833570651523,0.001257332190235938,0.7927778364718627,2.944117399716207
+red,circle,1,16,0.20901671281497636,0.29005231936593445,0.13810280912907674,5.065034003400998
+red,square,0,48,0.9562743938458542,0.7467203085342884,0.7755423050923582,7.117831369597269
+purple,triangle,0,51,0.4355354501763202,0.8591292672156728,0.8122903963006748,5.753094629505863
+
+
+
+$ head -5 data/colored-shapes.dkvp | mlr --ocsv --headerless-csv-output cat
+yellow,triangle,1,11,0.6321695890307647,0.9887207810889004,0.4364983936735774,5.7981881667050565
+red,square,1,15,0.21966833570651523,0.001257332190235938,0.7927778364718627,2.944117399716207
+red,circle,1,16,0.20901671281497636,0.29005231936593445,0.13810280912907674,5.065034003400998
+red,square,0,48,0.9562743938458542,0.7467203085342884,0.7755423050923582,7.117831369597269
+purple,triangle,0,51,0.4355354501763202,0.8591292672156728,0.8122903963006748,5.753094629505863
+
+
Regularizing ragged CSV
Miller handles compliant CSV: in particular, it’s an error if the
@@ -384,19 +500,6 @@ a,b,c
or, more simply,
-
-
-
-$ cat data/small
-a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
-a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
-a=wye,b=wye,i=3,x=0.20460330576630303,y=0.33831852551664776
-a=eks,b=wye,i=4,x=0.38139939387114097,y=0.13418874328430463
-a=wye,b=pan,i=5,x=0.5732889198020006,y=0.8636244699032729
-
-
@@ -423,7 +526,8 @@ allowing many of its verbs to process files that are (much) larger than the
amount of RAM present in your system. (Of course, Miller verbs such as
sort, tac, etc. all must ingest and retain all input records
before emitting any output records.) You can also use out-of-stream variables
-to perform multi-pass computations.
+to perform multi-pass computations, at the price of retaining all input records
+in memory.
Two-pass algorithms: computation of percentages