python处理fasta和fastq文件fasta文件格式

　　fasta文件格式：fasta 文件为一个 ID 对应一个 序列,可以是 转录本序列, 蛋白序列
　　＂＂＂
　　V350033524L1C001R00100020323/1
　　AAGCTGTCCCATCAATAGCTGCCGCTGAAGGGTGGGGCTGGATGGCGTAAGCTACAGCTGAAGGAAGAACGTGAGCACGAGGCACTGAGGTGATTGGCTG
　　V350033524L1C001R00100069491/1
　　AAGCTGTCCAATCAATAGCTGCCGCTGAAGGGTGGGGCTGGATGGCGTAAGCTACAGCTGAAGGAAGAACGTGAGCACGAGGCACTGAGGTGATTGGCTG
　　＂＂＂  读取 fasta 文件保存为字典,对应的 ID 为 key,序列为 value:with open(r＂E:/python练习文件/test.fa＂, ＂r＂) as fa:     fa_dict = {}     for line in fa:         # 去除末尾换行符         line = line.replace(＂ ＂,＂＂)         if line.startswith(＂>＂):             # 去除 > 号             seq_name = line[1:]             fa_dict[seq_name] = ＂＂         else:             # 去除末尾换行符并连接多行序列             fa_dict[seq_name] = line.replace(＂ ＂,＂＂)      # 查看结果,可以看到完整的把换行的序列拼接到一起了,保存为字典格式。 print(fa_dict) {＂V350033524L1C001R00100020323/1＂: ＂AAGCTGTCCCATCAATAGCTGCCGCTGAAGGGTGGGGCTGGATGGCGTAAGCTACAGCTGAAGGAAGAACGTGAGCACGAGGCACTGAGGTGATTGGCTG＂, ＂V350033524L1C001R00100069491/1＂: ＂AAGCTGTCCAATCAATAGCTGCCGCTGAAGGGTGGGGCTGGATGGCGTAAGCTACAGCTGAAGGAAGAACGTGAGCACGAGGCACTGAGGTGATTGGCTG＂, ＂V350033524L1C001R00100073913/1＂: ＂AAGCTGTCCTATCAATAGCTGCCGCTGAAGGGTGGGGCTGGATGGCGTAAGCTACAGCTCAAGGAAGAACGTGAGCACGAGGCACTGAGGTGATTGGCTG＂, ＂V350033524L1C001R00100149315/1＂: ＂AAGCTGTCCTATCAATAGCTGCCGCTGAAGGGTGGGGCTGGATGGCGTAAGCTACAGCTCAAGGAAGAACGTGAGCACGAGGCACTGAGGTGATTGGCTG＂, ＂V350033524L1C001R00100216048/1＂: ＂AAGCTGTCCAATCAATAGCTGCCGCTGAAGGGTGGGGCTGGATGGCGTAAGCTACAGCTCAAGGAAGAACGTGAGCACGAGGCACTGAGGTGATTGGCTG＂} 计算每条序列的 GC 含量及计算每条序列长度 # 遍历字典 for name,seq in fa_dict.items():     # 输出名称     print(name+ ＂ ＂)      # 计算 G,C 碱基数量     G_base = seq.count(＂G＂)     C_base = seq.count(＂C＂)      # 计算含量     G_per = G_base/len(seq)*100     C_per = C_base/len(seq)*100          #计算长度     length = len(seq)      # 保留小数点后两位     G_per = round(G_per,2)     C_per = round(C_per,2)      # 打印输出     print(＂G percent is: ＂+str(G_per)+  ＂%＂)     print(＂G percent is: ＂+str(C_per)+  ＂%＂)     print(＂lenth: ＂+str(length)) V350033524L1C001R00100020323/1  G percent is: 37.0% G percent is: 20.0% lenth: 100 V350033524L1C001R00100069491/1  G percent is: 37.0% G percent is: 19.0% lenth: 100 V350033524L1C001R00100073913/1  G percent is: 36.0% G percent is: 20.0% lenth: 100 V350033524L1C001R00100149315/1  G percent is: 36.0% G percent is: 20.0% lenth: 100 V350033524L1C001R00100216048/1  G percent is: 36.0% G percent is: 20.0% lenth: 100