python - Difficulty Creating column of Pandas Dataframe -

-

i wanted create new column of dataframe based on existing columns, want conditional on existing column in dataframe. following code not working. know why?

if cv['keyword'] == 0:     cv['left out'] = (cv['prediction numerator'] - (cv['rate'] *10000))/(cv['prediction denominator'] - 10000) else:     cv['left out'] = (cv['prediction numerator'] - (cv['rate'] *10000 * 10))/(cv['prediction denominator'] - (10000 * 10))

i'm getting following error:

traceback (most recent call last):   file "<stdin>", line 1, in <module>   file "c:\users\bwei\downloads\winpython-64bit-2.7.9.4\python-2.7.9.amd64\lib\site-packages\pandas\core\generic.py", line 709, in __nonzero__     .format(self.__class__.__name__)) valueerror: truth value of series ambiguous. use a.empty, a.bool(), a.item(), a.any() or a.all().

here's snippet of first 4 columns of dataframe.

        zip  keyword  prediction numerator  prediction denominator   0     01001        0        7650546.693200            40002.558782    1     01001        0        7650546.693200            40002.558782    2     01001        0        7650546.693200            40002.558782    3     01001        0        7650546.693200            40002.558782    4     01002        0            157.951741                0.718621    5     01002        0            157.951741                0.718621    6     01005        0        3600150.148240            20000.671431    7     01005        0        3600150.148240            20000.671431    8     01007        0        6932235.816260            30000.936191    9     01007        0        6932235.816260            30000.936191    10    01007        0        6932235.816260            30000.936191

thanks, ben

this should work:

cv.loc[cv['keyword']==0,'left out']=expression1 cv.loc[cv['keyword']!=0,'left out']=expression2

Comments

Post a Comment

Popular posts from this blog

python - No exponential form of the z-axis in matplotlib-3D-plots -

-
Image
i have similar problem described in how prevent numbers being changed exponential form in python matplotlib figure : i don't want (in special case) weird scientific formatting of axis. problem different have problem @ z -axis. 2-d plots can use ax.get_yaxis().get_major_formatter().set_useoffset(false) . , there no function ax.get_zaxis() what use format z -axis same way? edit: example: from mpl_toolkits.mplot3d import axes3d import numpy np import sys import matplotlib import matplotlib.pyplot pyplot def func(xi, ti): res = 10e3 + np.cos(ti) * np.sin(xi) return res if __name__ == '__main__': timespacing = 20 timestart = 0 timeend = 1 time = np.linspace(timestart, timeend, timespacing) widthspacing = 50 widthstart = 0 widthend = 3 width = np.linspace(widthstart, widthend, widthspacing) reslist = [] matplotlib.rcparams['legend.fontsize'] = 10 fig = pyplot.figure() ax = fig.gca(projection = '3d...
Read more

php - Best Light server (Linux + Web server + Database) for Raspberry Pi -

-
i install web server database on raspberry pi (little computer). computer has 1gb ram. i want know best combination: linux distribution , web server , dbms run local server multiple users minimal latency, use php on server. , best settings performance , not have bugs (memory usage, disable plugin, disable service, etc)? i thought light debian , lighttpd server , sqlite database. solution? i think lighttpd + sqlite great choice. linux distro, debian @ centos or tiny core linux , although i'm not sure of compatibility pi. obviously, can't go wrong raspbian if want use in production , more stable performance, few more pi's , set them in cluster .
Read more

c# - "Newtonsoft.Json.JsonSerializationException unable to find constructor to use for types" error when deserializing class -

-
i developing app in xamarin android. have splash screen serialize class , pass mainactivity using intent . when try deserialize in mainactivity error message : "serializationexception unable find constructor use types" serialization : void loaddata() { currency currency = new currency(this); intent = new intent(this, typeof(mainactivity)); intent.putextra("currency", newtonsoft.json.jsonconvert.serializeobject(currency)); startactivity(intent); } deserialization : cur = newtonsoft.json.jsonconvert.deserializeobject<currency> (intent.getstringextra("currency")); // error here class constructor : public currency(context context) { thiscontext = context; } i began experiencing problem after added parameter context context constructor. has caused this? how can solve it? possible serialize/deserialize class has parameters? you need have empty constructor in currency class in order deserialize it. ...
Read more