数组、字典创建Series import numpy as np mylist = list('qwe') # 列表 myarr = np.arange(3...
deque 这是一种队列类型,有队列类型的相关操作,可以弥补list这种广义表类型的某些不足,比如在前面插入较慢(这里你可以查找一些python的资料,对于python的list前段吧插入时会整个后移list,效率较低) 关于这种类型相应的方法支持可以参考后面附上的python library链接 Counter 可以理解为一个计数字典...
def split_words_reviews(data): text = list(data['Review'].values) clean_text = [] for t in text: clean_text.append(t.translate(str.maketrans('', '', punctuation)).lower().rstrip()) tokenized = [word_tokenize(x) for x in clean_text] all_text = [] for tokens in tokenized: fo...
str1 = 'I am a unicode string' type(str1) # type(str1) => 'str' str2 = b"And I can't be concatenated to a byte string" type(str2) # type(str2) => 'bytes' str3 = str1 + str2 --- Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError...
取各组平均值,减去空白对照组可以得到平均净用时,再除以净用时最长的concat组,可以得到下表: 可以看到,两者的差距确实存在,利用StringIO进行字符串拼接的用时仅为使用字符串相加用时的三成。当然,我们今天的主要目的不是为了测试StringIO有多好用。相信各位也注意到了一个有趣的事情,我们的stringio-r组,在测试代...
它的参数类型是int, list of int, None, 或者是默认的'infer' 它的功能是:Row numbers to use as the column names, and the start of the data. 也就是,它是把某一行作为列名,并且,这一行是数据开始的行。我们测试一下。刚才我们在a.csv文件中只写了两行数据,为了方便测试,我们写上5行数据(大部分...
to the intersection of the columns in both DataFrames. left_on : label or list, or array-like Column or index level names to join on in the left DataFrame. Can also be an array or list of arrays of the length of the left DataFrame. ...
StringDtype Timedelta TimedeltaIndex TimestampUInt16Dtype UInt32Dtype UInt64Dtype UInt64Index UInt8Dtypeapi array arrays bdate_range compatconcat core crosstab cut date_rangedescribe_option errors eval factorize get_dummiesget_option infer_freq interval_range io isnaisnull json_normalize lreshape melt ...
def concat_col_str_condition(df):# concat 2 columns with strings if the last 3 letters of the first column are 'pil' mask = df['col_1'].str.endswith('pil', na=False) col_new = df[mask]['col_1'] + df[mask]['col_2'] col_new.replace('pil', ' ', regex=True,...
--- 0 std::string paddle::platform::GetTraceBackString<std::string const&>(std::string const&, char const*, int) 1 paddle::platform::EnforceNotMet::EnforceNotMet(std::string const&, char const*, int) 2 paddle::operators::ConcatMKLDNNOpKernel<float>::Compute(paddle::framework::Execution...