Hi, I'm trying to edit lists using this function, which seems straightforward using the documentation example for deleting integers (shown below). However I'm guessing how to do this for removing even/odd numbers, prime numbers, multiple of a given number, etc., by basically copying the format, but the results below don't make any sense to me, surely because I don't know what I'm doing. Any help would be appreciated!
In[27]:= X = {1.5, 2, 3, 5, 7, 11, 13, 14, 17, 19, 23, 29, 30, 31, 37}
Out[27]= {1.5, 2, 3, 5, 7, 11, 13, 14, 17, 19, 23, 29, 30, 31, 37}
In[28]:= DeleteCases[X, _Integer]
Out[28]= {1.5}
In[29]:= DeleteCases[X, _Even]
Out[29]= {1.5, 2, 3, 5, 7, 11, 13, 14, 17, 19, 23, 29, 30, 31, 37}
In[30]:= DeleteCases[X, _Prime]
Out[30]= {1.5, 2, 3, 5, 7, 11, 13, 14, 17, 19, 23, 29, 30, 31, 37}