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How does e value for diamond blastx affects the result

Hi Istvan Albert Thank you for responding to the earlier post, here I want to discuss about a different issue regarding the e value to set while doing blastx using DIAMOND aligner against nr database. The purpose of doing blastx is to find out nerarest hits for the metgenomic redas for the fastq files. The .fastq files are big in size as well as the nr database so it is taking a long time for blastx to get done. Basically I want to obtain the blastx result faster. So, my question here is that if I lower the E value from the default evalue which is 1e-3 to 1e-20, would it affect my results? if yes, how? Also according to me I think lower the e value faster the output would be obtained. Please correct me if I am wrong.

Thanks Saraswati

analysis metagenomics genomics data

1 answer

Changing the e-value will affect the result output. It is not going to speed up your alignments. Hopefully you are using multiple threads with DIAMOND (that is what the real speed up will come from). Also plenty of memory and temp storage.

Thanks but if I decrease the e value how does my result get affected as in quality of the result.

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