Purpose of the describe object as opposed to native object?

MalcolmNunn

Hi there

I am trying to determine what benefit the describe object has over using the properties of the original object.

Does the describe object simply have all the properties that were present on the original object, plus some additional useful generic properties that are not present on the original objects (eg feature class, raster, etc).

Also, is there a way to retrieve a full list of an Arc objects properties?

Cheers

Mal

MatthewLewis

Hi Mal

I'm assuming your referring to the "Describe Object Properties" aspect of arcpy? e.g

<SPAN class="n">desc</SPAN> <SPAN class="o">=</SPAN> <SPAN class="n">arcpy</SPAN><SPAN class="o">.</SPAN><SPAN class="n">Describe</SPAN><SPAN class="p">(</SPAN><SPAN class="s" style="color: #a31515;">"C:/Data/chesapeake.gdb"</SPAN><SPAN class="p">)</SPAN>

if so the basic Describe functions (As shown here‌) are just some of the basic properties you can access. For Example

<SPAN class="kn" style="color: #0000ff;">import</SPAN> <SPAN class="nn">arcpy</SPAN>

<SPAN class="c" style="color: #008000;"># Create a Describe object</SPAN>
<SPAN class="c" style="color: #008000;">#</SPAN>
<SPAN class="n">desc</SPAN> <SPAN class="o">=</SPAN> <SPAN class="n">arcpy</SPAN><SPAN class="o">.</SPAN><SPAN class="n">Describe</SPAN><SPAN class="p">(</SPAN><SPAN class="s" style="color: #a31515;">"C:/Data/chesapeake.gdb"</SPAN><SPAN class="p">)</SPAN> 





<SPAN class="k" style="color: #0000ff;">print</SPAN> <SPAN class="s" style="color: #a31515;">"DataType: "</SPAN> <SPAN class="o">+</SPAN> <SPAN class="n">desc</SPAN><SPAN class="o">.</SPAN><SPAN class="n">dataType</SPAN>
<SPAN class="k" style="color: #0000ff;">
</SPAN>

However you can extend this function depending on the type of object your referencing. The example above used a geodatabase workspace. You could for example desibe a feature class. This would give you access to different properties. For Example

<SPAN class="c" style="color: #008000;"># Create a Describe object from the feature class</SPAN>


<SPAN class="n">desc</SPAN> <SPAN class="o">=</SPAN> <SPAN class="n">arcpy</SPAN><SPAN class="o">.</SPAN><SPAN class="n">Describe</SPAN><SPAN class="p">(</SPAN><SPAN class="s" style="color: #a31515;">"C:/data/arch.dgn/Point"</SPAN><SPAN class="p">)</SPAN>





<SPAN class="k" style="color: #0000ff;">print</SPAN> <SPAN class="s" style="color: #a31515;">"Feature Type: "</SPAN> <SPAN class="o">+</SPAN> <SPAN class="n">desc</SPAN><SPAN class="o">.</SPAN><SPAN class="n">featureType</SPAN>





<SPAN class="k" style="color: #0000ff;">print</SPAN> <SPAN class="s" style="color: #a31515;">"Shape Type : "</SPAN> <SPAN class="o">+</SPAN> <SPAN class="n">desc</SPAN><SPAN class="o">.</SPAN><SPAN class="n">shapeType</SPAN>

Or for a Raster

<SPAN class="n">desc</SPAN> <SPAN class="o">=</SPAN> <SPAN class="n">arcpy</SPAN><SPAN class="o">.</SPAN><SPAN class="n">Describe</SPAN><SPAN class="p">(</SPAN><SPAN class="s" style="color: #a31515;">"C:/data/preston.img"</SPAN><SPAN class="p">)</SPAN>

<SPAN class="c" style="color: #008000;"># Print some raster dataset properties</SPAN>
<SPAN class="c" style="color: #008000;"># </SPAN>
<SPAN class="k" style="color: #0000ff;">print</SPAN> <SPAN class="s" style="color: #a31515;">"Band Count:&nbsp; </SPAN><SPAN class="si" style="color: #a31515;">%d</SPAN><SPAN class="s" style="color: #a31515;">"</SPAN> <SPAN class="o">%</SPAN> <SPAN class="n">desc</SPAN><SPAN class="o">.</SPAN><SPAN class="n">bandCount</SPAN>
<SPAN class="k" style="color: #0000ff;">print</SPAN> <SPAN class="s" style="color: #a31515;">"Compression Type: </SPAN><SPAN class="si" style="color: #a31515;">%s</SPAN><SPAN class="s" style="color: #a31515;">"</SPAN> <SPAN class="o">%</SPAN> <SPAN class="n">desc</SPAN><SPAN class="o">.</SPAN><SPAN class="n">compressionType</SPAN>
<SPAN class="k" style="color: #0000ff;">print</SPAN> <SPAN class="s" style="color: #a31515;">"Raster Format:&nbsp; </SPAN><SPAN class="si" style="color: #a31515;">%s</SPAN><SPAN class="s" style="color: #a31515;">"</SPAN> <SPAN class="o">%</SPAN> <SPAN class="n">desc</SPAN><SPAN class="o">.</SPAN><SPAN class="n">format</SPAN>

You can get a full list here. I hope that answers your question and isn't just a waffle