class Bio::RestrictionEnzyme::DoubleStranded::AlignedStrands

Align two SingleStrand objects and return a Result object with primary and complement accessors.

Constants

Result

The object returned for alignments

Public Class Methods

align(a, b) click to toggle source

Pad and align two String objects without cut symbols.

This will look for the sub-sequence without left and right ‘n’ padding and re-apply ‘n’ padding to both strings on both sides equal to the maximum previous padding on that side.

The sub-sequences stripped of left and right ‘n’ padding must be of equal length.

Example:

AlignedStrands.align('nngattacannnnn', 'nnnnnctaatgtnn') # => 
 <struct Bio::RestrictionEnzyme::DoubleStranded::AlignedStrands::Result
   primary="nnnnngattacannnnn",
   complement="nnnnnctaatgtnnnnn">

Arguments

  • a: Primary strand

  • b: Complementary strand

Returns

Result object with equal padding on both strings

   # File lib/bio/util/restriction_enzyme/double_stranded/aligned_strands.rb
51 def self.align(a, b)
52   a = a.to_s
53   b = b.to_s
54   validate_input( strip_padding(a), strip_padding(b) )
55   left = [left_padding(a), left_padding(b)].sort.last
56   right = [right_padding(a), right_padding(b)].sort.last
57 
58   p = left + strip_padding(a) + right
59   c = left + strip_padding(b) + right
60   Result.new(p,c)
61 end
align_with_cuts(a,b,a_cuts,b_cuts) click to toggle source

Pad and align two String objects with cut symbols.

Example:

AlignedStrands.with_cuts('nngattacannnnn', 'nnnnnctaatgtnn', [0, 10, 12], [0, 2, 12]) # => 
  <struct Bio::RestrictionEnzyme::DoubleStranded::AlignedStrands::Result
    primary="n n n n^n g a t t a c a n n^n n^n",
    complement="n^n n^n n c t a a t g t n^n n n n">

Notes:

  • To make room for the cut symbols each nucleotide is spaced out.

  • This is meant to be able to handle multiple cuts and completely unrelated cutsites on the two strands, therefore no biological algorithm assumptions (shortcuts) are made.

The sequences stripped of left and right ‘n’ padding must be of equal length.

Arguments

  • a: Primary sequence

  • b: Complementary sequence

  • a_cuts: Primary strand cut locations in 0-based index notation

  • b_cuts: Complementary strand cut locations in 0-based index notation

Returns

Result object with equal padding on both strings and spacing between bases

    # File lib/bio/util/restriction_enzyme/double_stranded/aligned_strands.rb
 87 def self.align_with_cuts(a,b,a_cuts,b_cuts)
 88   a = a.to_s
 89   b = b.to_s
 90   validate_input( strip_padding(a), strip_padding(b) )
 91 
 92   a_left, a_right = left_padding(a), right_padding(a)
 93   b_left, b_right = left_padding(b), right_padding(b)
 94 
 95   left_diff = a_left.length - b_left.length
 96   right_diff = a_right.length - b_right.length
 97 
 98   (right_diff > 0) ? (b_right += 'n' * right_diff) : (a_right += 'n' * right_diff.abs)
 99 
100   a_adjust = b_adjust = 0
101 
102   if left_diff > 0
103     b_left += 'n' * left_diff
104     b_adjust = left_diff
105   else
106     a_left += 'n' * left_diff.abs
107     a_adjust = left_diff.abs
108   end
109 
110   a = a_left + strip_padding(a) + a_right
111   b = b_left + strip_padding(b) + b_right
112 
113   a_cuts.sort.reverse.each { |c| a.insert(c+1+a_adjust, cut_symbol) }
114   b_cuts.sort.reverse.each { |c| b.insert(c+1+b_adjust, cut_symbol) }
115 
116   Result.new( add_spacing(a), add_spacing(b) )
117 end
new() click to toggle source

Creates a new object.

Returns

Bio::RestrictionEnzyme::DoubleStranded::AlignedStrands object

Calls superclass method 
   # File lib/bio/util/restriction_enzyme/double_stranded/aligned_strands.rb
26 def initialize; super; end

Protected Class Methods

validate_input(a,b) click to toggle source 
    # File lib/bio/util/restriction_enzyme/double_stranded/aligned_strands.rb
123 def self.validate_input(a,b)
124   unless a.size == b.size
125     err = "Result sequences are not the same size.  Does not align sequences with differing lengths after strip_padding.\n"
126     err += "#{a.size}, #{a.inspect}\n"
127     err += "#{b.size}, #{b.inspect}"
128     raise ArgumentError, err
129   end
130 end