Reputation: 1023
I have a file (InputFile.txt
) containing blocks of integer numbers that each block is split using *
character. Each block contains some rows that each row contains three integers, for example:
4 1233 8
2 55 11
2 4 33
*
3 5 34
2 1 44
6 5 33
*
I want to read each block and put the integers in each block in a 2D array and do some processing on it. I found the following code:
f = File.read 'InputFile.txt'
f.split('*').each do |set|
set.split.map(&:to_i)
This code can read each block, But I don't know how to put each block in 2D array. I tried for example set[0][0]
and it returns 4, but when I tried set[0][1] it returns blank space. Can anyone tell me what should I do? I want to see 1233
as the second number.
Upvotes: 3
Views: 1397
Reputation: 110755
If the file is not overly large you can just "gulp" it into a string, split on the asterisks (along with whitespace on each side), and then break up the pieces.
Let's first write some data to file:
str =<<-BITTER_END
4 1233 8
2 55 11
2 4 33
*
3 5 34
2 1 44
6 5 33
*
5 4 1
22 65 98
13 15 71
BITTER_END
FName = 'temp'
IO.write(FName, str) #=> 75
Now we read and process the file:
IO.read(FName).
split('*').
map { |s| s.strip.split(/\n+/).map { |s| s.strip.split.map(&:to_i) } }
#=> [[[4, 1233, 8], [2, 55, 11], [2, 4, 33]],
# [[3, 5, 34], [2, 1, 44], [6, 5, 33]],
# [[5, 4, 1], [22, 65, 98], [13, 15, 71]]]
Here's another to write that. It's more verbose, but it makes it self-documenting, facilitates debugging and testing, and improves maintainability:
class String
def to_blocks(split_char)
split(split_char)
end
def to_lines
strip.split(/\n+/)
end
def to_arr_of_ints
strip.split.map(&:to_i)
end
end
Then:
IO.read(FName).to_blocks('*').map { |block|
block.to_lines.map { |line|
line.to_arr_of_ints } }
#=> [[[4, 1233, 8], [2, 55, 11], [2, 4, 33]],
# [[3, 5, 34], [2, 1, 44], [6, 5, 33]],
# [[5, 4, 1], [22, 65, 98], [13, 15, 71]]]
If you'd prefer not to monkey-patch String
, you could use Refinements, or just make one argument of each of the three methods a string.
Upvotes: 2
Reputation: 34336
f = File.read 'InputFile.txt'
data_array = f.split('*').map do |block|
block.split(/\n+/)
.map { |e| e.split(/\s+/)
.map(&:to_i) }
.reject { |a| a.empty? }
end
# => [[[4, 1233, 8], [2, 55, 11], [2, 4, 33]],
# [[3, 5, 34], [2, 1, 44], [6, 5, 33]]]
This will work for any number of blocks
separated by *
. And, in each block, rows
are separated by any number of new lines, and in each row, the integer
elements are separated by any number of white spaces.
As, each block is a graph
, and, three elements in each row
represents source_node
, dest_node
and weight
respectively, so, to access these information, you can do the following:
data_array.each_with_index do |row, index|
p "Graph: #{index}"
row.each do |inner_row|
p "source_node: #{inner_row[0]}, dest_node: #{inner_row[1]}, weight: #{inner_row[2]}"
end
p '- - -'
end
# => "Graph: 0"
# "source_node: 4, dest_node: 1233, weight: 8"
# "source_node: 2, dest_node: 55, weight: 11"
# "source_node: 2, dest_node: 4, weight: 33"
# "- - -"
# "Graph: 1"
# "source_node: 3, dest_node: 5, weight: 34"
# "source_node: 2, dest_node: 1, weight: 44"
# "source_node: 6, dest_node: 5, weight: 33"
Upvotes: 3
Reputation: 1661
f.split("*").each do |block|
result.push []
block.split("\n").each do |line|
result[-1].push line.split.map{ |i| i.to_i } unless line.split.size == 0
end
end
Upvotes: 1
Reputation: 481
Modified your code to add the nested array:
output = []
col = 0
row = 0
f = File.read 'InputFile.txt'
f.split('*').each do|set|
output[row] = []
set.split(' ').each do|item|
output[row][col] = item
col += 1
end
row +=1
col = 0
end
print output
Result:
[["4", "1233", "8", "2", "55", "11", "2", "4", "33"], ["3", "5", "34", "2", "1", "44", "6", "5", "33"]]
Just make sure not to have a trailing * otherwise it will create an empty inner array. Also wasn't sure if you wanted each new line of numbers in its own array or to read until the next astericks. I assumed read until the astericks.
Upvotes: 1