Fix labels for mlr histogram --auto (#1089)

internal/pkg/transformers/histogram.go

@@ -367,11 +367,11 @@ func (tr *TransformerHistogram) emitAuto(
 
 		outrec.PutReference(
 			tr.outputPrefix+"bin_lo",
-			mlrval.FromFloat((lo+float64(i))/mul),
+			mlrval.FromFloat(lo+(float64(i)/mul)),
 		)
 		outrec.PutReference(
 			tr.outputPrefix+"bin_hi",
-			mlrval.FromFloat((lo+float64(i+1))/mul),
+			mlrval.FromFloat(lo+(float64(i+1)/mul)),
 		)
 
 		for _, valueFieldName := range tr.valueFieldNames {

test/cases/verb-histogram/0005/cmd

@@ -0,0 +1 @@
+mlr --icsv --opprint histogram --nbins 9 --auto -f x test/input/histo2.csv

test/cases/verb-histogram/0005/expout

@@ -0,0 +1,10 @@
+bin_lo       bin_hi       x_count
+100.00000000 122.22222222 1
+122.22222222 144.44444444 0
+144.44444444 166.66666667 0
+166.66666667 188.88888889 0
+188.88888889 211.11111111 2
+211.11111111 233.33333333 0
+233.33333333 255.55555556 0
+255.55555556 277.77777778 0
+277.77777778 300.00000000 1

test/cases/verb-histogram/0006/cmd

@@ -0,0 +1 @@
+mlr --icsv --opprint histogram --nbins 9 --auto -f y test/input/histo2.csv

test/cases/verb-histogram/0006/expout

@@ -0,0 +1,10 @@
+bin_lo      bin_hi      y_count
+20.00000000 26.66666667 1
+26.66666667 33.33333333 0
+33.33333333 40.00000000 0
+40.00000000 46.66666667 2
+46.66666667 53.33333333 0
+53.33333333 60.00000000 0
+60.00000000 66.66666667 0
+66.66666667 73.33333333 0
+73.33333333 80.00000000 1

test/cases/verb-histogram/0007/cmd

@@ -0,0 +1 @@
+mlr --icsv --opprint histogram --nbins 9 --auto -f x,y test/input/histo2.csv

test/cases/verb-histogram/0007/expout

@@ -0,0 +1,10 @@
+bin_lo       bin_hi       x_count y_count
+20.00000000  51.11111111  0       3
+51.11111111  82.22222222  0       1
+82.22222222  113.33333333 1       0
+113.33333333 144.44444444 0       0
+144.44444444 175.55555556 0       0
+175.55555556 206.66666667 2       0
+206.66666667 237.77777778 0       0
+237.77777778 268.88888889 0       0
+268.88888889 300.00000000 1       0

test/input/histo2.csv

@@ -0,0 +1,5 @@
+x,y
+100,20
+200,40
+300,41
+200,80