| Further Examples: ReplacePart Here is a list. In[1]:=  This replaces {b, c} by X. In[2]:=  Out[2]=  This replaces the element b at position {2, 1} of vv by X. In[3]:=  Out[3]=  This replaces the elements at positions 2 and 4 of vv by X. In[4]:=  Out[4]=  Here is another list. In[5]:=  Here are the elements of vv and ww at the specified positions. In[6]:=  Out[6]=  In[7]:=  Out[7]=  This replaces b by and d by . In[8]:=  Out[8]=  The defined function EvaluateAt evaluates a held expression exactly at a specified list of positions. In[9]:=  Here 3 + 4 and 2*4 get evaluated. In[10]:=  Out[10]=  This defines the function ApplyAt which applies a function to the held parts of an expression at specified positions. In[11]:=  In[12]:=  In[13]:=  This applies Power at positions and . In[14]:=  Out[14]=  This defines the function ReplaceAt which applies a rule or a list of rules to the parts of an expression at specified positions. In[15]:=  In[16]:=  In[17]:=  In[18]:=  This applies a list of two rules at positions and . In[19]:=  Out[19]=  In[20]:=  |