Python Pandas Conditional count after groupby -


i have following dataframe:

   key1  key2 0      1 one      2 two    b   1 3    b   2 4      1 5    c   2

now, want group dataframe key1 , count column key2 value 1 result:

   key1   0      2 1    b   1 2    c   0

i usual count with:

df.groupby(['key1']).size()

but dont know how insert condition.

i tryed things this:

df.groupby(['key1']).apply(df[df['key2'] == 'one'])

but dont futher

it great if here

greetings

i think need add condition first:

#if need category c no values of 'one' df11=df.groupby('key1')['key2'].apply(lambda x: (x=='one').sum()).reset_index(name='count') print (df11)   key1  count 0         2 1    b      1 2    c      0

or use categorical key1, missing value added size:

df['key1'] = df['key1'].astype('category') df1 = df[df['key2'] == 'one'].groupby(['key1']).size().reset_index(name='count')  print (df1)   key1  count 0         2 1    b      1 2    c      0

if need combinations:

df2 = df.groupby(['key1', 'key2']).size().reset_index(name='count')  print (df2)   key1 key2  count 0     1      2 1     2      1 2    b  1      1 3    b  2      1 4    c  2      1  df3 = df.groupby(['key1', 'key2']).size().unstack(fill_value=0) print (df3) key2  1  2 key1                 2    1 b       1    1 c       0    1

Comments

Post a Comment

Popular posts from this blog

Is there a better way to structure post methods in Class Based Views -

i'm using class based views in django , never specify url in ajax calls , omit action parameter in form because know these requests go through post method of class based view. notice view - profile page make many requests depending on user updating on page - post method become convoluted , if/else mess example: def post(self, request, *args, **kwargs): # handle user changing available date if request.post.get('availabledate') != none: self.updateavailabledate(request) return jsonresponse({'result':'success'}) if request.post.get('newprojectname') != none: creative_user = creativeuserprofile.objects.get(id = request.user.id) project = project.create_project(creative_user, request.post['newprojectname']) project.save() return jsonresponse({'projectid': project.id }) if request.post.get('projectimage') != none , request.files['file']: proj...
Read more

What is happening when Matlab is starting a "parallel pool"? -

running parallel cpu processes in matlab starts command parpool() according documentation , function: [creates] special job on pool of workers, , [connects] matlab client parallel pool. this function takes bit of time execute, on order of 30 seconds. in other multi-cpu paradigms openmp, parallel execution seems totally transparent -- i've never noticed behavior analogous matlab (granted i'm not experienced parallel programming). so, happening between time parpool() called , when finishes executing? takes long? parallel computing toolbox enables run matlab code in parallel using several different paradigms (e.g. jobs , tasks, parfor , spmd , parfeval , batch processing), , run either locally (parallelised across cores in local machine) or remotely (parallelised across machines in cluster - either 1 own, or 1 in cloud). in of these cases, code run on matlab workers , copies of matlab without interactive desktop. if you're intending run on remo...
Read more

php - Cannot override Laravel Spark authentication with own implementation -

during login process of laravel spark need request token of remote api. api stores exact same users , passwords laravel spark application. therefore need username , non hashed password of user during authentication process. i thought overriding authenticated method solution problem. in routes/web.php override post /login endpoint , pointing endpoint own logincontroller: <?php namespace app\http\controllers\auth; use illuminate\support\facades\log; use illuminate\http\request; use laravel\spark\http\controllers\auth\logincontroller sparklogincontroller; class logincontroller extends sparklogincontroller { /** * create new login controller instance. * * @return void */ public function __construct() { parent::__construct(); } /** * handle successful authentication attempt. * * @param request $request * @param \illuminate\contracts\auth\authenticatable $user * @return response */ public fu...
Read more