title: Pandas Add Values in Interval By Specific Increment
body: <p>Is there a way using pandas functions to add values/rows by a particular increment?</p>
  
  <p>For example:
  This is what I have:</p>
  
  <pre><code>df = pd.DataFrame([1.1,2,2.8])
  df
        value other1  other2 
  zebra  0.3           250
  bunny  0.7           10
  rat    1.0           35
  cat    1.1   100
  dog    2.0   150
  mouse  2.8   125
  </code></pre>
  
  <p><strong>EDIT 1:</strong></p>
  
  <p>This is what I want, <strong>where ideally the inserted rows' index are whatever is easiest but the previous row names are preserved.</strong></p>
  
  <pre><code>df_goal = pd.DataFrame([1.1,1.2,1.3,1.4,1.5,1.6,1.7,1.8,1.9,2,2.1,2.2,2.3,2.4,2.5,2.6,2.7,2.8])
  df_goal
        value  other1   other2
  zebra  0.3             250
  1      0.4
  2      0.5
  3      0.6
  bunny  0.7             10
  5      0.8
  6      0.9
  rat    1.0             35
  cat    1.1    100
  1      1.2
  2      1.3
  3      1.4
  4      1.5
  5      1.6
  6      1.7
  7      1.8
  8      1.9
  dog    2.0   150
  10     2.1
  11     2.2
  12     2.3
  13     2.4
  14     2.5
  15     2.6
  16     2.7
  mouse  2.8   125
  </code></pre>
  
  <p><strong>EDIT 2:</strong></p>
  
  <p>Also I would like to keep the values of <code>other</code> columns that were there previously and any new rows are simply empty or zero.</p>