**Answers**

#### A PHP Error was encountered

Severity: Notice

Message: Undefined index: userid

Filename: views/question.php

Line Number: 191

Backtrace:

File: /home/prodcxja/public_html/questions/application/views/question.php

Line: 191

Function: _error_handler

File: /home/prodcxja/public_html/questions/application/controllers/Questions.php

Line: 433

Function: view

File: /home/prodcxja/public_html/questions/index.php

Line: 315

Function: require_once

## expanding (adding a row or column) a scipy.sparse matrix

Suppose I have a NxN matrix M (lil_matrix or csr_matrix) from scipy.sparse, and I want to make it (N+1)xN where M_modified[i,j] = M[i,j] for 0 <= i < N (and all j) and M[N,j] = 0 for all j. Basically, I want to add a row of zeros to the bottom of M and preserve the remainder of the matrix. Is there a way to do this without copying the data?