Re: [Discuss-gnuradio] Avoiding divide by zero in case of input being zero.

Hi Anshul - Do you have a public repo for folks to use for debugging? Given that your system otherwise passes test and probably works, the best way to get feedback is via providing the source code. I really have no other suggestions; sorry! - MLD

On Fri, Mar 30, 2018, at 1:49 PM, Anshul Thakur wrote:

I used a circular buffer of finite size to keep the past 'N' power values of the sample stream in my block as a part of creating a running sum. This buffer is initialized to 0 in the constructor. 

The running sum of powers is used to compute the average power used in computing signal correlation.

I have a capture stream (cfile) to test the operation of the block. The test case uses a vector_source_c block to read the contents of the file into memory. The unit tests pass without error. 

However, when I use the block in a flowgraph in that reads the same file from a file source block gnuradio_companion, I am getting the first few sample values as 0 which cause a divide by zero problem. This messes up the rest of the running sum. I don't want to put an 'if' block that checks for the zero condition as it is not expected that a device/stream would ever spit out zero values.

(a) Why am I getting the initial zero samples from the file block in gnuradio_companion and non-zero values when using a vector_source in unit tests?

(b) What can I do about it (here specifically as a fix to the situation, and a general guideline to always remember)?

I am using GNURadio version 3.7.12.