来自R,我天真地尝试
dfE_fitted['E_after'] = dfE_fitted['E_before']
它给了我
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead
好吧,那我就试试:
dfE_fitted.loc[:,'E_after'] = dfE_fitted['E_before']
这给了我
/Library/Fram
当我运行这段代码时
df = raw.copy() # making a copy of dataframe raw
df['new col'] = ''
for i in range(len(df)):
df['new col'].loc[i] = 'some thing'
我得到了这个警告(警告1):
SettingWithCopyWarning: A value is trying to be set on a copy of a slice from a DataFrame
See the caveats in
我试着用逻辑条件更新熊猫的数据框架,但是,它失败了,错误如下,
df[df.b <= 0]['b'] = 0
A value is trying to be set on a copy of a slice from a DataFrame. Try using .loc[row_indexer,col_indexer] = value instead
我该怎么做呢?
数据:
df = pd.DataFrame({'a': np.random.randn(4), 'b': np.random.randn(4)})
a
我给一个dataframe分配了一些值,并得到了以下警告消息:
# temp is some data
x = temp[temp.loc[:, cat] == 1]
x.loc[:, "category_id"] = cat # warning occurred here
/home/jupyter-inhyeok_yoo/.conda/envs/test/lib/python3.6/site-packages/pandas/core/indexing.py:1596: SettingWithCopyWarning:
A value is trying to be set
我有一个问题,有关绘制移动平均值,做小组。我已经从Kaggle 获取了数据集。我应用以下条件提取了几行。
new_df_A = new_df[(new_df.Name == 'A')]
new_df_A.sort_values(by=['Name', 'Date'])
我尝试通过实现以下代码来计算30天的移动平均值
for cols in new_df_A.columns:
if cols not in ['Name', 'Date',]:
new_df_A['ma_'+co
如何将数据帧中给定列的每个元素与标量相乘?(我已经尝试过了,但似乎找不到正确的解决方案)
做一些类似的事情:
df['quantity'] *= -1 # trying to multiply each row's quantity column with -1
给我一个警告:
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead
注意:如果可能的话,我不想在数据帧上迭代,也不想做
我有一个数据帧,其中所有列都是连续变量,我希望根据频率(因此绑定具有相同的大小)在绑定中对它们进行离散化。
为了做到这一点,我只需要应用pd.cut函数并迭代这些列,但是我得到了以下错误:
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead
See the caveats in the documentation: https://pandas.pydata.org/pandas-docs/stabl
我想用firstname + ' ' + (姓氏的首字母)替换dataframe中重复的名字。
Last Name First Name Value
Simpson Bart 10
Monroe Lisa 20
Colbert Bart 15
变成了
Last Name First Name Value
Simpson Bart S 10
Monroe Lisa 20
Colbert Bart C 15
到目前为止我已经做过了
df.loc
我试图删除不等于列表中元素的dataframe中的所有内容,但我得到了以下警告:
C:/Users/jalco/PycharmProjects/project/main.py:119: SettingWithCopyWarning:
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead
See the caveats in the documentation: https://pandas.pydat
我知道这是一个非常常见的错误,然而,在我的情况下,我不能弄清楚为什么会发生在我身上。
我得到了:
SettingWithCopyWarning:
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead
See the caveats in the documentation: http://pandas.pydata.org/pandas-docs/stable/indexing.html#i
我有一个Pandas DataFrame 'Date‘专栏,我正试图将它转换为datetime。它正在转换,并提高了"SettingWithCopyWarning“
我试着遵循其他很好的解释,比如:和其他解释,但我想不出答案。谢谢大家!
我的原始代码:
import numpy as np
import pandas as pd
data = pd.DataFrame(pd.read_excel('Restaurant Shifts Data.xlsx', na_values='-')) # (-) value in cash
data.
我有一个pandas dataframe,我想转换一些列,并将转换重新分配到现有的dtaframe中: df.loc[:,df.columns != 'target'].pct_change(-1) 如果我这样做了: df.loc[:,df.columns != 'target'] = df.loc[:,df.columns != 'target'].pct_change(-1) 我得到一个警告: A value is trying to be set on a copy of a slice from a DataFrame.
Try usi
请建议执行以下操作的正确方法。
data_tr['loss'] = data_tr['loss'].apply(lambda x:x**0.25)
<ipython-input-368-59c3c700212e>:1: SettingWithCopyWarning:
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead
请参阅文档中的注意事项:
data_tr
我已经使用groupby导出了一个数据帧。 我正在尝试使用下面的代码在“volume”列的基础上设置一个新的列“rank”。 代码工作正常,但给出一个警告- A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead 下面是我的代码。我会感谢指导,因为我没有太多的经验在Python/熊猫。 filter_condition = ohlcv_m30_groupby_df['min_volume'
木星手册将返回此警告:
*C:\anaconda\lib\site-packages\pandas\core\indexing.py:337: SettingWithCopyWarning:
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead
请参阅文档中的注意事项:
self.obj[key] = _infer_fill_value(value)
C:\anaconda\lib\site-packa
我想把一列复制到一个新列中。我使用以下代码:
df['income10']=df['income'].copy(deep=False)
我知道这个错误:
/Users/hairy/ipykernel/ipykernel_launcher.py:2: SettingWithCopyWarning:
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead
See the ca
我在pandas中有一个简单的多索引数据帧。我正在尝试添加更多的子列,但我被警告不要使用
SettingWithCopyWarning:
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead
我不能设法得到正确的索引咒语来使这项工作。
附加一个代码片段,该代码片段包含我想要添加的列的排序的一个简单的、无层次的示例。然后,我有一个层次化的示例,在该示例中,我演示了如何添加新的顶级列,但不能正确操作单个子列
我有一只熊猫的数据
df = pd.DataFrame({'AKey':[1, 9999, 1, 1, 9999, 2, 2, 2],\
'AnotherKey':[1, 1, 1, 1, 2, 2, 2, 2]})
我希望将一个新值赋给特定的列,并为该列中具有特定值的每个元素分配一个新值。
假设我希望将新的值8888分配给具有值9999的元素。我尝试了以下几点:
df[df["AKey"]==9999]["AKey"]=8888
但是它返回以下错误:
A value is trying to be set on a co
我对Python (和熊猫)完全陌生。我确实试图解决这个问题,但是,如果没有收到以下警告,我就无法解决这个问题:
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead
我有两个列,包含一个人的名字和姓氏。我要寻找的是一种向数据框架df中添加包含全名的新列的方法。以下代码与警告一起工作:
df['Full Name'] = df['First Name'] + " &
我收到错误
SettingWithCopyWarning: A value is trying to be set on a copy of a slice from a DataFrame. Try using .loc[row_indexer,col_indexer] = value instead
在我的代码df['mean'] = df.groupby('col1').transform('mean')上,我想将计算作为一个新列添加。
我理解了错误信息,并了解到我需要使用.loc来解决这个问题,但我不知道如何将.loc包含到当前代码中。
我这样做是为了替换字符串中的一个字符:
df['msg'] = df['msg'].str.replace(u'X','W')
收到警告:
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead
然后,我试图以正确的方式(我认为)进行同样的转换,以避免这种警告:
df.loc[:,'msg'] = df.loc[:,'m
我试着做一件非常简单的事情,我通过将两个数字相除来创建一个速率,现在我试图将这个速率添加到一个数据帧中:
df['rate'] = rate
它给出了这个错误:
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead
那么我到底做错了什么呢?我也尝试过使用.loc,但不起作用。
我正在尝试获取链接,并通过TinyURL推送它们。我有一个包含登录链接的数据框列,我想单独采取这些,并添加到列‘微网址’,tiny_urlize链接。 for index, row in df.iterrows():
df.loc[index, 'Tiny Url'] = tiny_urlize(row['Login Link']) 我得到的错误如下所示: A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_i
df_masked.loc[:, col] = df_masked.groupby([df_masked.index.month, df_masked.index.day])[col].\
transform(lambda y: y.fillna(y.median()))
即使在使用了.loc之后,我也得到了foll。错误,我该如何修复它?
Anaconda\lib\site-packages\pandas\core\indexing.py:476: SettingWithCopyWarning:
A value is trying to be set on a co
我有一个演示程序:
import pandas as pd
d = {'foo':[100, 111, 222],
'bar':[333, 444, 555]}
df = pd.DataFrame(d)
list = [333,444]
dferg = df.loc[df.bar.isin(list)]
dferg['test'] = 123
我收到警告:
SettingWithCopyWarning:
A value is trying to be set on a copy of a slice from a DataF
我有两个熊猫数据帧,一个名为df1,另一个名为df2: import pandas as pd
df1 = pd.DataFrame({'PERCENTAGE': [0.35,0.1105,0.0487,0.98],})
df2 = df1.loc[df1['PERCENTAGE'] > 0.4] 我正在尝试使用以下代码在df2中创建一个新列: df2['NEW_COLUMN'] = 1 - df2['PERCENTAGE'] 但是我得到了以下错误: C:\PATH:
A value is trying to be
我有一个包含多个列的dataframe,我只想用新值df['Z'] = df['A'] % df['C']/2更新一个列。但是,即使我使用.loc[]方法,或者当我使用drop()列并再次添加它时,我仍然会收到loc[]消息。
:75: SettingWithCopyWarning:
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value instead
虽然警告用.ass
我有代码行
df = df.groupby(by=['col_A','col_B'])['float_col_c']
df.loc[:,'amount_cumulative'] = df.apply(lambda x: x.cumsum())
这就引发了警告:
/anaconda3/lib/python3.6/site-packages/pandas/core/indexing.py:362: SettingWithCopyWarning:
A value is trying to be set on a copy of a s
我试图使用中的建议在熊猫的单元格中设置一个值。但是因为我有一个日期时间作为索引,所以我似乎无法访问特定的单元格。有没有一种有效的方法来做到这一点,没有任何警告,如SettingWithCopyWarning: A value is trying to be set on a copy of a slice from a DataFrame. Try using .loc[row_indexer,col_indexer] = value instead。
import pandas as pd
y = pd.DataFrame(data = 0,
index
我的数据里有-
RecordType Latitude Longitude Name
L 28.2N 70W Jon
L 34.3N 56W Dan
L 54.2N 72W Rachel
Note__:所有列的dtype是object__。
现在,在我的最后数据中,我只想包括那些纬度和经度落在一定范围内的行(比如24 < Latitude < 30和79 < Longitude < 87)。
嗨,我想通过删除丢失的信息来操作数据,并使所有字母小写。但对于小写转换,我会收到这样的警告:
E:\Program Files Extra\Python27\lib\site-packages\pandas\core\frame.py:1808: UserWarning: Boolean Series key will be reindexed to match DataFrame index.
"DataFrame index.", UserWarning)
C:\Users\KubiK\Desktop\FamSeach_NameHandling.py:18: Setti
我有一个表情 df_1['result'][df_1['result'].isnull() & df_1['id'].notnull() ] = df_1['M'][df_1['result'].isnull() & df_1['id'].notnull()].apply(lambda x: [0]*len(x)) 我得到了以下错误A value is trying to be set on a copy of a slice from a DataFrame. Try using
我在这个命令上得到了这个错误SettingWithCopyWarning。该命令工作正常,但返回此错误。在没有收到错误的情况下,是否有其他方法可供选择?
# Grab DataFrame rows where column has certain values and create 'signature' string
test['signature'] = np.where(test['id'].isin(list_of_bad_ids), 'id has a bad value in it', test['s
以前,我问,有3个答案,但其中3个给出警告,通常我忽略这一点,但这是为了生产目的,所以我不能。以下是答案和警告:
1
s = df2.set_index('Nation')['Capital City']
df1['Capital'] = df1['Country'].map(s).fillna(df1['Capital'])
警告
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexe
您好,我正在尝试添加一个新的列("A")在现有的数据框中,其中的值将是1或3,基于其中一列("B")的信息。
df["A"] = np.where(df["B"] == "reported-public", 1,3)
执行此操作时,我收到警告消息:
<ipython-input-239-767754e40f8a>:4: SettingWithCopyWarning:
A value is trying to be set on a copy of a slice from a DataFrame.
T
我正在使用ipython3 notebook并运行以下命令:
separ['RT'] = separ['text'].str.contains(r"^(?=.*\bRT\b\s@\b).*$",
case=False) == True
我得到的警告如下:
-c:3: SettingWithCopyWarning:
A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_indexer,col_indexer] = value i