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TOC
1. 背景形容
最近在写一个后端我的项目,次要的操作就是依据用户的前端数据,在后端关上我的项目中的代码文件,批改对应地位的参数,因为在目前的后端我的项目中常常应用这个操作,所以简略总结一下。
1. 文件门路:./test.c
2. 文件内容
……
case EPA:
chan_desc->nb_taps = 7;
chan_desc->Td = .410;
chan_desc->channel_length = (int) (2*chan_desc->sampling_rate*chan_desc->Td + 1 + 2/(M_PI*M_PI)*log(4*M_PI*chan_desc->sampling_rate*chan_desc->Td));
sum_amps = 0;
chan_desc->amps = (double *) malloc(chan_desc->nb_taps*sizeof(double));
chan_desc->free_flags=chan_desc->free_flags|CHANMODEL_FREE_AMPS ;
for (i = 0; i<chan_desc->nb_taps; i++) {chan_desc->amps[i] = pow(10,.1*epa_amps_dB[i]);
sum_amps += chan_desc->amps[i];
}
for (i = 0; i<chan_desc->nb_taps; i++)
chan_desc->amps[i] /= sum_amps;
chan_desc->delays = epa_delays;
chan_desc->ricean_factor = 1;// 待批改地位
chan_desc->aoa = 0;// 待批改地位
chan_desc->random_aoa = 0;// 待批改地位
chan_desc->ch = (struct complexd **) malloc(nb_tx*nb_rx*sizeof(struct complexd *));
chan_desc->chF = (struct complexd **) malloc(nb_tx*nb_rx*sizeof(struct complexd *));
chan_desc->a = (struct complexd **) malloc(chan_desc->nb_taps*sizeof(struct complexd *));
……
2. 单行批改 - 操作步骤
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读取文件
应用 python 中的 open()函数进行文件读取,将数据存储在缓冲区。#1. 读取文件 path='./test.c' with open(path, 'r') as file: file_content = file.read()
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查找文件替换地位
以查找chan_desc->ricean_factor = 1;// 待批改地位
为例,查找这句话的终点和起点。## 注:此步骤须要 import re #2. 查找文件替换地位 start_index=file_content.find('chan_desc->ricean_factor =')# 终点 end_index=file_content.find('chan_desc->aoa =',start_index)# 起点 if end_index==-1 or start_index==-1: print('未找到待批改地位') #此时失去的两个指针,别离指向了待批改地位的终点和起点,如下图所示:
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设置替换文件内容
假如目前只批改这一行的参数,#3. 设置替换文件内容 ricean_factor=3# 假如这是要批改的参数信息 updata_content=file_content[:start_index]# 获取这行代码之前的内容 update_content+='chan_desc->ricean_factor ='+str(ricean_factor)+';// 待批改地位'# 批改这行代码 update_content+=file_content[end_index:]# 获取这行代码之后的内容 #此时失去的 update_content 就是批改后的残缺文件内容,只批改了 ricean_factor 这一行的值
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写入文件
同样应用 python 中的 open 函数。#4. 写入文件 if update_content!="":# 如果批改内容不为空 with open(path, 'w') as file:#w 示意笼罩写入,之前的内容都会被笼罩 file.write(update_content)
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总代码
整体的代码如下所示:import re #1. 读取文件 path='./test.c' with open(path, 'r') as file: file_content = file.read() #2. 查找文件替换地位 start_index=file_content.find('chan_desc->ricean_factor =')# 终点 end_index=file_content.find('chan_desc->aoa =',start_index)# 起点 if end_index==-1 or start_index==-1: print('未找到待批改地位') #3. 设置替换文件内容 ricean_factor=3# 假如这是要批改的参数信息 updata_content=file_content[:start_index]# 获取这行代码之前的内容 update_content+='chan_desc->ricean_factor ='+str(ricean_factor)+';// 待批改地位'# 批改这行代码 update_content+=file_content[end_index:]# 获取这行代码之后的内容 #4. 写入文件 if update_content!="":# 如果批改内容不为空 with open(path, 'w') as file:#w 示意笼罩写入,之前的内容都会被笼罩 file.write(update_content)
3. 多行批改 - 操作步骤
- 多行批改思路
多行批改有两种批改思路,如果批改局部比拟集中,则可间接替换一整块的字符串内容,如果批改局部较为扩散,则须要独自查找批改地位,而后再别离进行替换。 -
多行批改 - 整块替换
try: with open(file_path, "r") as file: file_content = file.read() except Exception as e: return str(e) # 设置改写内容 updated_content = "" # 查找批改 start_index_1 = file_content.find("start_sentence")# 要确保查找元素的唯一性 end_index_1 = file_content.find("end_sentence",start_index_1,) if start_index_1 == -1 or end_index_1 == -1: print("未找到待批改地位") return -1 # updated_content = file_content[:start_index_1]# 获取这行代码之前的内容 updated_content += "start_sentence 和 end_sentence 之间的 sentence_1;\n" updated_content += "start_sentence 和 end_sentence 之间的 sentence_2;\n" updated_content +=file_content[end_index_1:] ## 此时 updated_content 就是批改后的残缺文件内容 if updated_content != "": with open(file_path, "w") as file: file.write(updated_content) else: print("批改失败") return -1
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多行批改 - 部分替换
try: with open(file_path, "r") as file: file_content = file.read() except Exception as e: return str(e) # 设置改写内容 updated_content = "" # 查找批改 start_index_1 = file_content.find("start_sentence_1")# 要确保查找元素的唯一性 end_index_1 = file_content.find("end_sentence_1",start_index_1,) start_index_2 = file_content.find("start_sentence_2",end_index_1) end_index_2 = file_content.find("end_sentence_2",start_index_2,) start_index_3 = file_content.find("start_sentence_3",end_index_2) end_index_3 = file_content.find("end_sentence_3",start_index_3,) start_index_4 = file_content.find("start_sentence_4",end_index_3) end_index_4 = file_content.find("end_sentence_4",start_index_4,) if ( start_index_1 == -1 or end_index_1 == -1 or start_index_2 == -1 or end_index_2 == -1 or start_index_3 == -1 or end_index_3 == -1 or start_index_4 == -1 or end_index_4 == -1 ): print("未找到待批改地位") return -1 # updated_content = file_content[:start_index_1]# 获取这行代码之前的内容 updated_content += "start_sentence_1 和 end_sentence_1 之间的内容" updated_content +=file_content[end_index_1:start_index_2] updated_content += "start_sentence_2 和 end_sentence_2 之间的内容" updated_content +=file_content[end_index_2:start_index_3] updated_content += "start_sentence_3 和 end_sentence_3 之间的内容" updated_content +=file_content[end_index_3:start_index_4] updated_content += "start_sentence_4 和 end_sentence_4 之间的内容" updated_content += file_content[end_index_4:] ## 此时 updated_content 就是批改后的残缺文件内容 if updated_content != "": with open(file_path, "w") as file: file.write(updated_content) else: print("批改失败") return -1
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