output to csv in a similar manner 'print' outputs to terminal? - ruby

Question

the logic included in my ruby code is a little difficult to translate into a csv output, is there a way to append each value in a similar manner that print works when outputting to the terminal?
cop_log is a hash of thousands of records
cop_log = { 'A1' => 'val1', 'B1' => 'val2', 'C1' => 'val3', 'D1' => 'val4, 'E1' => 'val5', 'F1' => 'val6', 'G1' => 'val7', 'H1' => 'val8', 'I1' => 'val9', 'J1' => 'val10, 'K1' => 'val11', 'A2' => 'val12', 'B2' => 'val13', 'C2' => 'val14', 'D2' => 'val15, 'E2' => 'val16', 'F2' => 'val17', 'G2' => 'val18', 'H2' => 'val19', 'I2' => 'val20', 'J2' => 'val21, 'K2' => 'val22'}
cop_log.each do |key, value|
if key.include?('K')
print "#{value}\n"
elsif key.include?('A')
print "#{job_number},#{pm_lookup[job_number]},#{value},"
elsif key.include?('B') || key.include?('C') || key.include?('D') ||
key.include?('E') || key.include?('F') || key.include?('G') ||
key.include?('H') || key.include?('I') || key.include?('J')
print "#{value},"
end
end
currently outputs in the terminal like this, i want it to print to a csv in the same way:
val1, val2, val3, val4, val5, val6, val7, val8, val9, val10, val11
val12, val13, val14, val15, val16, val17, val18, val19, val10, val21, val22
reading the documentation it looks like the common route is to do the following,
CSV.open("path/to/file.csv", "wb") do |csv|
csv << ["row", "of", "CSV", "data"]
csv << ["another", "row"]
# ...
end
unfortunately the structure of my code is going to make that a little difficult....

Answer 1

This is very confusing and, if cleaned up, would help make your code much more readable and maintainable:
if key.include?('K')
print "#{value}\n"
elsif key.include?('A')
print "#{job_number},#{pm_lookup[job_number]},#{value},"
elsif key.include?('B') || key.include?('C') || key.include?('D') ||
key.include?('E') || key.include?('F') || key.include?('G') ||
key.include?('H') || key.include?('I') || key.include?('J')
print "#{value},"
end
What is key? A string of characters or a single character? If you're matching single characters you could do something like:
if key == 'K'
print "#{value}\n"
elsif key == 'A'
print "#{job_number},#{pm_lookup[job_number]},#{value},"
elsif ('B'.. 'J').include?(key)
elsif
print "#{value},"
end
and even convert:
elsif ('B'.. 'J').include?(key)
to:
elsif ('B'..'J') === key
If you're searching for a character match inside strings:
if key['K']
print "#{value}\n"
elsif key['A']
print "#{job_number},#{pm_lookup[job_number]},#{value},"
elsif key[/[B-J]/]
print "#{value},"
end
At this point you're ready to tackle cleaning up the CSV output. I'd recommend starting over using one of the basic examples of CSV output in the class documentation. I'd also recommend carefully reading "Comma-separated values" so you're more familiar with the expectations of a CSV formatted file.
(Note: At this point the input sample hash was added to the question showing the actual format of the keys.)
I'll let you figure out how to incorporate CSV, but meditate on this:
cop_log = { 'A1' => 'val1', 'B1' => 'val2', 'C1' => 'val3', 'D1' => 'val4', 'E1' => 'val5', 'F1' => 'val6', 'G1' => 'val7', 'H1' => 'val8', 'I1' => 'val9', 'J1' => 'val10', 'K1' => 'val11', 'A2' => 'val12', 'B2' => 'val13', 'C2' => 'val14', 'D2' => 'val15', 'E2' => 'val16', 'F2' => 'val17', 'G2' => 'val18', 'H2' => 'val19', 'I2' => 'val20', 'J2' => 'val21', 'K2' => 'val22'}
cop_log.values.each_slice(11) do |slice|
puts slice.join(',')
end
# >> val1,val2,val3,val4,val5,val6,val7,val8,val9,val10,val11
# >> val12,val13,val14,val15,val16,val17,val18,val19,val20,val21,val22
You need to rely on the CSV class to create CSV files; The format isn't as simple as it seems.
Here's a first pass of how I'd write the code:
require 'csv'
cop_log = { 'A1' => 'val1', 'B1' => 'val2', 'C1' => 'val3', 'D1' => 'val4', 'E1' => 'val5', 'F1' => 'val6', 'G1' => 'val7', 'H1' => 'val8', 'I1' => 'val9', 'J1' => 'val10', 'K1' => 'val11', 'A2' => 'val12', 'B2' => 'val13', 'C2' => 'val14', 'D2' => 'val15', 'E2' => 'val16', 'F2' => 'val17', 'G2' => 'val18', 'H2' => 'val19', 'I2' => 'val20', 'J2' => 'val21', 'K2' => 'val22'}
job_number = 1
pm_lookup = [0, 1]
CSV.open('./foo.csv', 'w') do |csv|
cop_log.group_by{ |k, v| k[1] }.values.each do |row|
csv << [ job_number, pm_lookup[job_number], *row.map{ |k, v| v } ]
end
end
After running, foo.csv contains:
1,1,val1,val2,val3,val4,val5,val6,val7,val8,val9,val10,val11
1,1,val12,val13,val14,val15,val16,val17,val18,val19,val20,val21,val22
We don't know what your expected output is, since you didn't tell us, but you could work from that code and figure it out.
Here's a break-down of the preprocessing of the data:
cop_log.group_by{ |k, v| k[1] } # => {"1"=>[["A1", "val1"], ["B1", "val2"], ["C1", "val3"], ["D1", "val4"], ["E1", "val5"], ["F1", "val6"], ["G1", "val7"], ["H1", "val8"], ["I1", "val9"], ["J1", "val10"], ["K1", "val11"]], "2"=>[["A2", "val12"], ["B2", "val13"], ["C2", "val14"], ["D2", "val15"], ["E2", "val16"], ["F2", "val17"], ["G2", "val18"], ["H2", "val19"], ["I2", "val20"], ["J2", "val21"], ["K2", "val22"]]}
.values # => [[["A1", "val1"], ["B1", "val2"], ["C1", "val3"], ["D1", "val4"], ["E1", "val5"], ["F1", "val6"], ["G1", "val7"], ["H1", "val8"], ["I1", "val9"], ["J1", "val10"], ["K1", "val11"]], [["A2", "val12"], ["B2", "val13"], ["C2", "val14"], ["D2", "val15"], ["E2", "val16"], ["F2", "val17"], ["G2", "val18"], ["H2", "val19"], ["I2", "val20"], ["J2", "val21"], ["K2", "val22"]]]
In the code above I'm making sure the input is in an expected order, in this case I'm grouping by single-digit rows. More robust code would use \d+ instead of 1 and would also sort to force the appropriate order.
This is really important any time you're massaging data from one format into another for later reuse. While current Rubies guarantee that a hash will maintain its insertion order, it's not a good practice to assume since old versions of Ruby didn't do that, and other languages you port the code to might not maintain order. Instead always program defensively, making sure you're going to return consistent results. To what extent you do that is something you'll learn when you find out a previous attempt wasn't enough. Programming is fun that way.
Finally, any time your code feels awkward or isn't flowing it's time to back up and look at what you're doing.

Answer 2

Couldn't you do this?
CSV.open("path/to/file.csv", "wb") do |csv|
cop_log.each do |key, value|
if key.include?('A')
csv << [ job_number, pm_lookup[job_number], value ]
elsif key.include?('K') || key.include?('B') || key.include?('C') || key.include?('D') ||
key.include?('E') || key.include?('F') || key.include?('G') ||
key.include?('H') || key.include?('I') || key.include?('J')
csv << [ value ]
end
end
end

Answer 3

def write_csv(cop_log, io = $stdout)
cop_log.each do |key, value|
if key.include?('K')
io.print "#{value}\n"
elsif key.include?('A')
io.print "#{job_number},#{pm_lookup[job_number]},#{value},"
elsif key.include?('B') || key.include?('C') || key.include?('D') ||
key.include?('E') || key.include?('F') || key.include?('G') ||
key.include?('H') || key.include?('I') || key.include?('J')
io.print "#{value},"
end
end
end
Then
File.open('path/to/file.csv', 'w') do |f|
write_csv(cop_log, f)
end

Answer 4

re fector the code
CSV.open("test.csv", "ab") do |csv|
b = {}
check_num = 0
cop_log.each do |key, value|
num = key.gsub(/[^\d]/, '').to_i
next if num < 8 ||
key.include?('L') || key.include?('M') || key.include?('N') ||
key.include?('O') || key.include?('P') || key.include?('Q') ||
key.include?('R') || key.include?('S') || key.include?('T') ||
key.include?('U') || key.include?('V')
a = { key => value }
b.merge!(a)
end # end of each loop
i = 8
while ((b.length / 9) - 7) > i do
csv << [ job_number, pm_lookup[job_number], b["A#{i}"], b["B#{i}"],
b["C#{i}"], b["D#{i}"], b["E#{i}"], b["F#{i}"], b["G#{i}"],
b["H#{i}"], b["I#{i}"], b["J#{i}"], b["K#{i}"] ]
i += 1
end
end # end of CSV.open