使用字典转换字母

本文介绍了使用字典转换字母的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我想写一个程序，将字典中匹配字符的字符转换为与该字符相关联的值。如果字典是{'A'：'T'，'C'：'G'，'T'：'A'，'G'：'C'}，字符串是'AAG'，输出应该是'TTC '。

编辑：这是我现在感谢你的一些答案：

def matching_codons（complementments，poolA）： answer = [] codon ='' counter = 0 for i in poolA： for a in i： codon + = complements [a] counter + = 1 if counter == 3： answer.append（codon）

不幸的是，这只能翻译前3个字母 - 如何让它继续运行循环？ p>

注意：poolA是字符串列表，例如['AAG'，'TAC'，'CGG'，'GAT'，'TTG'，'GTG'，'CAT'，'GGC'，'ATT'，'TCT']

注意2：我不能硬编码任何像翻译表，因为技术上可以更改字典输入

解决方案

另一种解决方案是使用字符串中的maketrans

from string import maketrans complementTrans = maketrans（ACTG，TGAC） poolA = ['AAG '，'TAC'，'CGG'，'GAT'，'TTG'，'GTG'，'CAT'，'GGC'，'ATT'，'TCT'] [codon.translate密码子in poolA]

您将获得：

['TTC'，'ATG'，'GCC'，'CTA'，'AAC'，'CAC'，'GTA'，'CCG'，'TAA'，'AGA']

奖金

biopython库，例如

poolA = ['AAG'，'TAC'，'CGG'，'GAT'，'TTG'，'GTG'，'CAT'，'GGC'，'ATT'，'TCT'] 来自Bio.Seq import Seq 来自Bio.Alphabet import IUPAC [str（Seq（seq，IUPAC.unambiguous_dna）plement（））for seq in poolA]

您会得到相同的结果

Bonus 2

修复您的代码，删除不必要的变量 counter

poolA = ['AAG'，'TAC'，'CGG'，'GAT'，'TTG'，'GTG'，'CAT' GGC'，'ATT'，'TCT'] complements = {'A'：'T'，'C'：'G'，'T'：'A'，'G'：'C'} def match_codons（complementments，poolA）： answer = [] for i in poolA： codon =''迭代 for a in i： codon + = complements [a] answer.append（codon）＃在次要外部，密码子有三个结束迭代 return answer matching_codons（complementments，poolA）

I'm trying to write a program that converts letters matching a key in a dictionary to the value associated with that key e.g. if the dictionary is {'A':'T', 'C':'G', 'T':'A', 'G':'C'} and the string is 'AAG' the output should be 'TTC'.

EDIT: This is what I've got now thanks to some of your answers:

def matching_codons(complements, poolA): answer = [] codon = '' counter = 0 for i in poolA: for a in i: codon+= complements[a] counter += 1 if counter == 3: answer.append(codon)

Unfortunately this only translates the first 3 letters - how can I make it keep running through the loop?

Note: poolA is a list of strings e.g. ['AAG', 'TAC', 'CGG', 'GAT', 'TTG', 'GTG', 'CAT', 'GGC', 'ATT', 'TCT']

Note2: I can't hard-code anything like a translation table because technically the dictionary input can be changed

解决方案

another solution is using maketrans from string

from string import maketrans complementTrans = maketrans("ACTG", "TGAC") poolA = ['AAG', 'TAC', 'CGG', 'GAT', 'TTG', 'GTG', 'CAT', 'GGC', 'ATT', 'TCT'] [codon.translate(complementTrans) for codon in poolA]

you get:

['TTC', 'ATG', 'GCC', 'CTA', 'AAC', 'CAC', 'GTA', 'CCG', 'TAA', 'AGA']

Bonus

It is always better to use biopython library, for example

poolA = ['AAG', 'TAC', 'CGG', 'GAT', 'TTG', 'GTG', 'CAT', 'GGC', 'ATT', 'TCT'] from Bio.Seq import Seq from Bio.Alphabet import IUPAC [str(Seq(seq, IUPAC.unambiguous_dna)plement()) for seq in poolA]

you get the same result

Bonus 2

Fixing your code, I remove unnecessary variable counter

poolA = ['AAG', 'TAC', 'CGG', 'GAT', 'TTG', 'GTG', 'CAT', 'GGC', 'ATT', 'TCT'] complements = {'A':'T', 'C':'G', 'T':'A', 'G':'C'} def matching_codons(complements, poolA): answer = [] for i in poolA: codon = '' # inside of for, codon reset in each iteration for a in i: codon+= complements[a] answer.append(codon) # outside of secondary for, codon have three leters to end iterations return answer matching_codons(complements, poolA)