我正在尝试修改现有df中的单元格-如果我发现没有字母字符的字符串(例如“ *”),则将其设置为“ 0.0”字符串,并且在处理所有单元格时,我尝试转换列数字类型。 但是由于某种原因设置为“ 0.0”并不会反映在结果df
中for i, col in enumerate(cols):
for ii in range(0, df.shape[0]):
row = df.iloc[ii]
value = row[col]
if isinstance(value, str):
if not( utils.representsInt(value) or utils.representsFloat(value) ) and re.search('[a-zA-Z]', x) is None:
df.iat[ii, i] = "0.0"
df[col] = df[col].astype(np.float_)
#df[col] = df[col].to_numeric() #this throws error that Series does not have to_numeric()
我遇到错误
could not convert string to float: 'cat'
当我打印df时,我看到值未更改。 可能是什么问题?
谢谢!
df
f289,f290,f291,f292,f293,f294,f295,f296,f297,f298,f299,f300,f301,f302,f303,f304,f305,f306,f307,f308,f309,f310
01M015,P.S. 015 Roberto Clemente,Elementary,1.0,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*
01M019,P.S. 019 Asher Levy,Elementary,1.0,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*
01M020,P.S. 020 Anna Silver,Elementary,1.0,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*
01M034,P.S. 034 Franklin D. Roosevelt,K-8,1.0,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,14
01M063,The STAR Academy - P.S.63,Elementary,1.0,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,6
01M064,P.S. 064 Robert Simon,Elementary,1.0,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*
01M110,P.S. 110 Florence Nightingale,Elementary,1.0,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*
01M134,P.S. 134 Henrietta Szold,Elementary,1.0,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*
01M137,P.S. 137 John L. Bernstein,Elementary,1.0,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*
01M140,P.S. 140 Nathan Straus,K-8,1.0,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*
01M142,P.S. 142 Amalia Castro,Elementary,1.0,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*
01M184,P.S. 184m Shuang Wen,K-8,1.0,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*
01M188,P.S. 188 The Island School,K-8,1.0,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,*,10
因此,在这种情况下,我希望此df
具有“ 0.0”而不是“ *”,并且这些列在转换后具有数值数据类型,例如float
答案 0 :(得分:2)
您可以更改返回0.0的条件,我将其设置为测试x=="*"
df.iloc[:,3:] = df.iloc[:,3:].applymap(lambda x: 0.0 if x=="*" else x)
f289 f290 f291 ... f308 f309 f310
0 01M015 P.S. 015 Roberto Clemente Elementary ... 0.0 0.0 0
1 01M019 P.S. 019 Asher Levy Elementary ... 0.0 0.0 0
2 01M020 P.S. 020 Anna Silver Elementary ... 0.0 0.0 0
3 01M034 P.S. 034 Franklin D. Roosevelt K-8 ... 0.0 0.0 14
4 01M063 The STAR Academy - P.S.63 Elementary ... 0.0 0.0 6
5 01M064 P.S. 064 Robert Simon Elementary ... 0.0 0.0 0
6 01M110 P.S. 110 Florence Nightingale Elementary ... 0.0 0.0 0
7 01M134 P.S. 134 Henrietta Szold Elementary ... 0.0 0.0 0
8 01M137 P.S. 137 John L. Bernstein Elementary ... 0.0 0.0 0
9 01M140 P.S. 140 Nathan Straus K-8 ... 0.0 0.0 0
10 01M142 P.S. 142 Amalia Castro Elementary ... 0.0 0.0 0
11 01M184 P.S. 184m Shuang Wen K-8 ... 0.0 0.0 0
12 01M188 P.S. 188 The Island School K-8 ... 0.0 0.0 10
更新
定义功能
def f(value) :
if isinstance(value, str):
if not(utils.representsInt(value) or utils.representsFloat(value) ) and re.search('[a-zA-Z]', x) is None:
return 0.0
return float(value)
将其应用于每个单元格
df = df.applymap(f)