2d histogram making - linux

Question

I have a data file containing two columns, like
1.1 2.2
3.1 4.5
1.2 4.5
3.2 4.6
1.1 2.3
4.2 4.9
4.2 1.1
I would like to make a histogram from the two columns, i.e. to get this output (if the step size (or bin size, as we talking about histogramming) equals to 0.1 in this case)
1.0 1.0 0
1.0 1.1 0
1.0 1.2 0
...
1.1 1.0 0
1.1 1.1 0
1.1 1.2 0
...
1.1 2.0 0
1.1 2.1 0
1.1 2.2 1
...
...
Can anybody suggest me something? It would be nice, if I can set the the range of values of the colmuns. In the above case the 1st column values goes from 1 to 4, and the same as for the second column.
EDITED: updated in order to handle more general data input, e.g. float numbers. The step size in the above case is 0.1, but it would be nice if it can be tunable for other settings, i.e. if step range (bin size) is for example 0.2, or 1.0.
If the step size is for example 1.0, then if I have 1.1 and 1.8 they have the same bin, we have to handle them together, for example (the range in this case let us say 4 for both of the two columns 0.0 ... 4.0)
1.1 1.8
2.5 2.6
1.4 2.1
1.3 1.5
3.3 4.0
3.8 3.9
4.0 3.2
4.0 4.0
output (if the bin size = 1.0)
1 1 2
1 2 1
1 3 0
1 4 0
2 1 0
2 2 1
2 3 0
2 4 0
3 1 0
3 2 0
3 3 1
3 4 1
4 1 0
4 2 0
4 3 1
4 4 1

Answer 1

awk 'END {
for (i = 0; ++i <= l;) {
for (j = 0; ++j <= l;)
printf "%d %d %d %s\n", i, j, \
b[i, j], (j < l ? x : ORS)
}
}
{
f[NR] = $1; s[NR] = $2
b[$1, $2]++
}' l=4 infile
You may try this (not thoroughly tested):
awk -v l=4 -v bs=0.1 'BEGIN {
if (!bs) {
print "invalid bin size" > "/dev/stderr"
exit
}
split(bs, t, ".")
t[2] || fl++
m = "%." length(t[2]) "f"
}
{
fk = fl ? int($1) : sprintf(m, $1)
sk = fl ? int($2) : sprintf(m, $2)
f[fk]; s[sk]; b[fk, sk]++
}
END {
if (!bs) exit 1
for (i = 1; int(i) <= l; i += bs) {
for (j = 1; int(j) <= l; j += bs) {
if (fl) {
fk = int(i); sk = int(j); m = "%d"
}
else {
fk = sprintf(m, i); sk = sprintf(m, j)
}
printf "%s" m OFS m OFS "%d\n", (i > 1 && fk != p ? ORS : x), fk, sk, b[fk, sk]
p = fk
}
}
}' infile

Answer 2

You can try this in bash:
for x in {1..4} ; do
for y in {1..4} ; do
echo $x%$y 0
done
done \
| join -1 1 -2 2 - -a1 <(sed 's/ /%/' FILE \
| sort \
| uniq -c \
| sort -k2 ) \
| sed 's/ 0 / /;s/%/ /'
It creates the table with all zeros in the last column, joins it with the real results (classic frequency table sort | uniq -c) and removes the zeros from the lines where a different number should be shown.

Answer 3

One solution in perl (sample output and usage to follow):
#!/usr/bin/perl -W
use strict;
my ($min, $step, $max, $file) = #ARGV
or die "Syntax: $0 <min> <step> <max> <file>\n";
my %seen;
open F, "$file"
or die "Cannot open file $file: $!\n";
my #l = map { chomp; $_} qx/seq $min $step $max/;
foreach my $first (#l) {
foreach my $second (#l) {
$seen{"$first $second"} = 0;
}
}
foreach my $line (<F>) {
chomp $line;
$line or next;
$seen{$line}++;
}
my $len = #l; # size of list
my $i = 0;
foreach my $key (sort keys %seen) {
printf("%s %d\n", $key, $seen{$key});
$i++;
print "\n" unless $i % $len;
}
exit(0);