externalise code solutions

it will be easier to maintain and test
it will be easier for student to recover good code

source/_static/code/amplicon_len.py

+
+def amplicon_len(seq, primer_1, primer_2):
+    """
+    given primer_1 and primer_2 
+    return the lenght of the amplicon
+    primer_1 and primer_2 ar present and in this order 
+    in sequence 
+    """
+    primer_1 = primer_1.upper()
+    primer_2 = primer_2.upper()
+    sequence = sequence.upper()
+    pos_1 = sv40_sequence.find(primer_1)
+    pos_2 = sv40_sequence.find(primer_2)
+    amplicon_len = pos_2 + len(primer_2) - pos_1
+    return amplicon_len
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source/_static/code/fasta_to_one_line.py

+
+def fasta_2_one_line(seq):
+    header_end_at = find('\n')
+    seq = seq[:header_end_at + 1]
+    seq = seq.replace('\n', '')
+    return seq
+

source/_static/code/gc_percent.py

+
+def gc_percent(seq):
+    gc_pc =  float(seq.count('g') + seq.count('c')) / float(len(seq))
+    return gc_pc
\ No newline at end of file

source/_static/code/vol_of_sphere.py

+import math
+
+def vol_of_sphere(radius):
+    """
+    compute the volume of sphere of a given radius
+    """
+    
+    vol = float(4)/float(3) * float(math.pi) * pow(radius, 3)
+    return vol